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Cardiac Surgery During Pregnancy
Cardiac Surgery During Pregnancy Harold A. Collins, M.D., Rollin A. Daniel, Jr., M.D., and H. William Scott, Jr., M.D.
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ardiac disease is currently one of the most frequent causes of maternal disability and death. Significant improvements in the obstetrical management of toxemia, infection, and hemorrhage have enhanced the relative importance of cardiac disease during pregnancy. T h e recorded incidence of cardiac disease in pregnancy in several large series varies from 1.5 to 3.7% [13, 171. Rheumatic heart disease accounts for approximately 90% of the organic cardiac lesions encountered during pregnancy. Mendelson’s collected report of 3,353 pregnancies complicated by rheumatic valvular disease showed 75% to have dominant mitral stenosis, 10 to 15% combined mitral and aortic lesions, and the remainder to have other valvular problems [12]. Mitral stenosis is therefore the most significant acquired valvular lesion encountered during pregnancy. Congenital heart disease is present in 7 to S%, and the remainder is composed of hypertensive and miscellaneous cardiac conditions. Associated pregnancy was previously considered one of the contraindications to surgery for heart disease. Within the last decade, however, surgical therapy for cardiac disease during pregnancy has been utilized with increasing frequency. Most of the surgical experience has been with mitral stenosis, since this is the cardiac lesion most frequently coexisting with pregnancy and an adequate operation has been available for several years. Surgical therapy recently has been used increasingly for other acquired and congenital cardiac lesions during pregnancy. Mendelson has stated that no evidence exists that the gravid state increases operative risks or that antepartum cardiovascular surgery jeopardizes the unborn baby [12]. If this is clearly the case, more frequent and effective use of cardiac surgery during pregnancy can be anticipated. During the last several years we have had the opportunity to participate in the surgical care of 9 patients with cardiac disease during pregnancy. This experience forms the basis for this report. From the Department of Surgery, Vanderbilt University Medical Center, Nashville, Tenn. Supported in part by U.S. Public Health Service Grant HE 08195. Presented at the Fourteenth Annual Meeting of the Southern Thoracic Surgical Association, Dallas, Tex., Nov. 9-11, 1967.
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Cardiac Surgery During Pregnancy PHYSIOLOGICAL CHANGES IN N O R M A L PREGNANCY
Several physiological events occur during the course of normal pregnancy [l, 3, 6, 121. Among the more significant is a gradual increase in oxygen consumption beginning at about the end of the first trimester and attaining a maximum at term. The pulse rate usually increases gradually, starting at about the tenth week and achieving a maximum at about the thirtieth week. The usual increase is 10 to 15 beats per minute. T h e systolic blood pressure normally remains stable, whereas the diastolic pressure may decrease due to a diminished peripheral resistance. T h e cardiac output also increases to a maximum level at about the thirtieth week. Some recent evidence indicates that the cardiac output may be significantly increased during the first trimester [18]. T h e cardiac output may be increased 30 to 50% at its maximum. Blood volume is also maximally increased at the eighth month due to an increase in both red cell mass and plasma volume. T h e increase in plasma volume is proportionately greater, resulting in a reduced hematocrit. Total body water is maximally increased at term and is usually 15 to 20% greater than normal. Alterations in blood volume play an important role in the patterns of cardiac output and related phenomena, but the placenta may also function as an arteriovenous fistula. A return to the normal nonpregnant state is achieved by the second postpartum week. T h e physiological aberrations exhibited during normal pregnancy can easily be misinterpreted as signs of organic heart disease. Increased venous pressure, edema, capillary pulsation, transient basilar rales, systolic murmurs, split and accentuated heart sounds, and changes in cardiac contour and electrocardiographic patterns may all accompany normal pregnancy. It is thus occasionally hazardous to first make the diagnosis of cardiac disease during pregnancy in the absence of definitive signs. CASE REPORTS MITRAL STENOSIS
Case 1 . A 22-year-oldwhite woman entered Vanderbilt University Hospital for the first time on August 1, 1955, complaining of shortness of breath. She was in the fifth month of pregnancy. She had delivered a viable infant 8 months before admission, but had been in severe cardiac failure during the last trimester. For 2 months preceding the current hospitalization, she had been severely dyspneic with any exertion, had two pillow orthopnea, and repeated episodes of hemoptysis. The clinical findings were compatible with severe mitral stenosis. A mitral commissurotomy was accomplished. She tolerated the operation well and proceeded through pregnancy without significant difficulty. A normal infant was born 4 months postoperatively. Seven years later recurrent mitral stenosis necessitated a second commissurotomy which was well tolerated. Case 2. A 19-year-oldwhite woman in the fourth month of pregnancy and
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COLLINS, DANIEL, AND SCOTT in congestive cardiac failure was admitted to Vanderbilt University Hospital on August 2, 1961. Approximately 3 months previously she had developed acute pulmonary edema, hemoptysis, and paroxysmal nocturnal dyspnea. Despite digitalis administration she continued to have severe symptoms. All the clinical findings were compatible with mitral stenosis. She tolerated mitral commissurotomy well. Her pregnancy postoperatively was uncomplicated, and she delivered a normal infant 5 months postoperatively. Case 3. A 35-year-old white woman was admitted to Vanderbilt University Hospital on July 24, 1961, complaining of weakness and shortness of breath. She was in the second month of pregnancy. The presence of mitral stenosis had been known for 12 years. She previously had uneventful pregnancies in 1945 and 1959. At the time of admission the findings were compatible with mitral stenosis, atrial fibrillation, and congestive cardiac failure. After digitalis administration, catheterization of the left side of the heart was accomplished and demonstrated severe mitral stenosis. Mitral commissurotomy was performed without complication. In the postoperative period a normal sinus rhythm was restored. Pregnancy continued uneventfully, and a normal infant was delivered 7 months later. Two days following delivery cerebral embolization occurred, with a transient hemiparesis. She subsequently did well with no residual weakness. COARCTATION OF THE AORTA
Case 4. A 27-year-old white woman in the second month of pregnancy was admitted to Vanderbilt University Hospital on February 20, 1950, because of hypertension. The patient's first knowledge of hypertension was in 1944, at the age of 21, during her first pregnancy. During this pregnancy she apparently had a greatly elevated blood pressure, edema, shortness of breath, headaches, and blind spots before her eyes. Since that time, her blood pressure had been elevated on all examinations. Three kidney stones were removed in 1945. At the time of her admission she was 2 months pregnant. Her blood pressure was 170/100 mm. Hg. All of the physical findings were compatible with coarctation of the aorta. A retrograde aortogram revealed a well-defined coarctation. In view of the difficulty that the patient had experienced with her previous pregnancy, therapeutic abortion was accomplished on March 4, 1950. On March 10, 1950, a left thoracotomy was performed. An extensive amount of reaction was present about the aorta. The reaction was so striking about the proximal segment of aorta that it appeared dangerous to apply clamps. The left subclavian artery was accordingly divided preparatory to establishing a subclavian anastomosis to the aorta distal to the coarctation. After division of the subclavian artery, it was evident that a dissecting aneurysm was present. It did not appear possible to surgically alleviate the coarctation and thoracotomy closure was accomplished. The patient tolerated the procedure well, and the postoperative course was uncomplicated. The patient was subsequently admitted to Vanderbilt University Hospital on December 1, 1957, with a history of increasing dyspnea and precordial pain for the previous year. At this time the blood pressure in the right arm was 190/90 mm. Hg. The physical examination was otherwise essentially unchanged. A left thoracotomy was performed on December 5, 1957. At this operation it was possible to resect the coarctation including the left subclavian artery and replace the resected segment with an aortic homograft. She tolerated the operation well and her postoperative period was relatively smooth. She was next admitted to the hospital on July 1, 1962. In the interim she had done extremely well. She had no limitation of activity and was on no medication. Blood pressure in the right arm was 120/85 mm. Hg. A retrograde aortogram was performed which demonstrated a widely patent graft without evidence of any degenerative change. Case 5. A 16-year-old white girl was admitted to Vanderbilt University
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Cardiac Surgery During Pregnancy Hospital on August 7, 1953, because of high blood pressure. One month before admission the patient experienced sharp, crushing precordial pain and thereafter had a hysterical episode. She had been hospitalized and found to have high blood pressure; the blood pressure in the arms was 180190 mm. Hg. She had findings typical of a coarctation of the aorta. In addition, her uterus was enlarged to about the size of a two-month pregnancy. An electrocardiogram was considered to be within normal limits. A chest x-ray revealed notching of the ribs posteriorly. The heart did not appear to be enlarged. An Ascheim-Zondek test confirmed the presence of pregnancy. On August 15, 1953, resection of the coarctation and primary anastomosis were accomplished without difficulty. The postoperative period was essentially uneventful. Postoperatively the blood pressure stabilized at about 140190 mm. Hg. She proceeded through pregnancy without difficulty and delivered a healthy, viable infant 7 months postoperatively. Case 6. A 31-year-old white woman in the third month of pregnancy was admitted to Vanderbilt University Hospital for the first time on May 5, 1956. For 2 to 3 months before admission she had noted increasing weakness and easy fatigability. Hypertension had been discovered 7 years previously during her second pregnancy. She had apparently gone through two previous pregnancies without difficulty. On examination the blood pressure in the upper extremities was 185190 mm. Hg. The pulses in the legs were extremely weak. Routine clinical laboratory data were within normal limits. An electrocardiogram was interpreted as being normal. On a chest film an aneurysm of the descending thoracic aorta was apparent. An aortogram demonstrated a severe coarctation immediately distal to the origin of the left subclavian artery and an 8 cm. aortic aneurysm just beyond the coarctation. On May 21, 1956, the coarctation and the aneurysm were excised and replaced with a freeze-dried aortic homograft. Postoperatively she did quite well without significant difficulty. She proceeded through her pregnancy without any significant difficulty. The blood pressures were usually in the range of 120-130/70 mm. Hg. A normal infant was born in September, 1956. She was readmitted to this hospital in 1962, at which time a retrograde thoracic aortogram was obtained. This revealed a normally functioning aortic homograft. PATENT DUCTUS ARTERIOSUS
Case 7. A 19-year-old white woman in the second month of pregnancy was admitted to Vanderbilt University Hospital on October 2, 1963, for investigation of a cardiac murmur. A murmur had been known since shortly after birth. The patient had been essentially asymptomatic throughout life. On examination the blood pressure was 120/40 mm. Hg. She was a well-developed young female in no distress. A continuous murmur was localized over the second and third intercostal spaces. The routine clinical laboratory data were within normal limits. An immunological test for pregnancy was positive. Cardiac catheterization was accomplished on October 3, 1963, and revealed a patent ductus arteriosus. A patent ductus, 12 mm. in diameter, was divided on October 8, 1963. Her postoperative convalescence was entirely uneventful, and she subsequently delivered a normal infant. Case 8. A 22-year-old white woman entered Vanderbilt University Hospital for the second time on June 16, 1961. This patient had previously been admitted on January 12, 1961, with subacute bacterial endarteritis superimposed on a patent ductus arteriosus. She had known of a murmur all of her life. She had previously had one normal pregnancy. At the time of her previous hospitalization she had received intravenous penicillin therapy for 6 weeks, with apparent cure of the bacterial endarteritis. It had been planned that the patient have cardiac catheterization, followed by division of the patent ductus arteriosus. Following her discharge, however, she had become pregnant and was admitted on June 16 VOL.
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COLLINS, DANIEL, AND SCOTT about 2% months pregnant. All of her physical findings were compatible with a patent ductus arteriosus. The routine clinical laboratory data were within normal limits. An electrocardiogram suggested left ventricular hypertrophy. A patent ductus arteriosus, 10 mm. in diameter, was divided on June 26, 1961. The patient tolerated the procedure well, and the postoperative convalescence was uneventful. She was discharged from the hospital and proceeded through an uneventful pregnancy with the delivery of a normal infant approximately 6 months later. ATRIAL SEPTAL DEFECT
Case 9. A 22-year-old white woman was admitted to Vanderbilt University Hospital for a heart operation on June 23, 1962. She had previously been admitted in January, 1958, with a coarctation of the aorta. Cardiac catheterization at that time had revealed a pulmonary artery systolic pressure of approximately 100 mm. Hg; the brachial arterial systolic pressure was approximately 200 mm. Hg. Operation was performed on January 13, 1958, at which time a coarctation was excised and a patent ductus divided. An aortic homograft was anastomosed between the two ends of the aorta. Postoperatively she did well and had little subsequent difficulty. She was subsequently readmitted to the hospital in 1962. At that time she was normotensive. She continued to have an audible systolic murmur. A retrograde aortogram demonstrated a normally functioning aortic homograft. Cardiac catheterization was accomplished and demonstrated an atrial septal defect. The pulmonary artery pressure at this time was approximately 50120 mm. Hg. During cardiopulmonary bypass on June 26, 1962, an ostium secundum type of atrial septal defect approximately 2 x 3 cm. was closed. The patient tolerated the operation well, and her postoperative period was essentially uncomplicated. It was not known until postoperatively that she was in the second month of pregnancy at the time of operation. She proceeded through a normal pregnancy and delivery of a normal infant. DISCUSSION
The precise role of cardiac surgery during pregnancy is still evolving. Certainly the majority of women with cardiac disease can and do proceed through pregnancy with medical management. Admirably low rates for maternal mortality have been reported in large series of patients with pregnancies complicated by cardiac disease. Burwell and Metcalfe [3] reported a mortality rate of 1.O% in 298 patients with heart disease during pregnancy. A maternal mortality of 0.8% was described by Mendelson [13] in a group of 3,690 pregnancies complicated by heart disease. From such data it has been concluded erroneously that cardiac disease is well tolerated during pregnancy by all patients. It is clear, however, that the majority of patients in these series had mild forms of cardiac disease with little functional limitation. Functional classification according to the New York Heart Association’s criteria provides the most reliable prognostic information with regard to risk for the pregnant patient with cardiac disease. Those patients in Class I and Class I1 tolerate the hemodynamic burden of pregnancy without serious difficulty. Most of the mortality occurs in Class I11 and Class IV patients, and in reported series has varied from 4.2 to 18.7% [3, 171. It 304
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is also well documented that heart failure is the major cause of maternal death in cardiac subjects and that the onset of decompensation and time of death are related to the hemodynamic burden of pregnancy D31. We are in accord with the view of Harken and Taylor [8] who have stated that “physicians and surgeons alike would prefer to avoid any and all intrapartum operations. Surgery should be undertaken only when it is clear that the result desired can be best attained by an operation and the risks are acceptable.” Much of the controversy regarding cardiac surgery during pregnancy relates to a definition of the risks involved, both to the mother and the fetus. T h e most extensive and convincing data are those concerned with mitral commissurotomy during pregnancy. Brock [21, Cooley and Chapman [41, Logan and Turner [lo], and Mason [ l l ] reported in 1952 on a total of 11 patients who underwent mitral commissurotomy during pregnancy, with one maternal death and one premature delivery. In 1965 Ueland [16] reported on a collected series of 5 14 patients in whom mitral commissurotomy had been performed during pregnancy. Most patients were in Class I11 and Class IV. In the entire series there were a total of 9 maternal deaths (1.8%) and 44 fetal deaths (8.6%).A comparison of similar Class 111 and Class IV patients treated medically reveals a maternal mortality of 4.2 to 18.7% and a fetal mortality of up to 50%. It is tempting to attribute the relatively low mortality in the patients having commissurotomy solely to the excellence of surgical management. It is recognized, however, that such results are possible only with cooperative and enlightened medical participation. Upon the basis of our own limited experience and the collected experiences of others, it appears that mitral commissurotomy during pregnancy is an acceptable procedure from the standpoint of maternal and fetal mortality. From the reported statistics the mortality is considerably less in those Class I11 and Class IV patients who are treated surgically than in those receiving intensive medical management. In fact, the mortality for mitral commissurotomy during pregnancy is significantly less than that reported for comprehensive series of patients having mitral commissurotomy in the nongravid state. The reasons for this are readily apparent. T h e majority of pregnant patients with mitral stenosis are in the second and third decades of life and usually have not developed atrial fibrillation, advanced cardiac decompensation or heavily calcified valves. In our experience these conditions have been associated with the greatest morbidity and mortality following mitral commissurotomy and are ordinarily encountered in an older age group. Even if the mortality for mitral commissurotomy during pregnancy can be demonstrated to be acceptably low, the procedure would VOL.
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have little relevance if the patient’s clinical condition were not significantly benefited. It is our impression from our limited experience, as well as that of others [S], that a gratifying response occurs in most pregnant patients following mitral commissurotomy. T h e manifestations of cardiac failure are quickly relieved and the medical management of the continuing pregnancy is greatly simplified. Mitral commissurotomy is a palliative procedure, and reoperation may ultimately be necessary, as exemplified by our Case 1. It does not appear rational, however, to preclude the initial operation upon the basis of possible recurrent difficulties. In our opinion the indications for mitral commissurotomy in the pregnant patient are probably the same as in the nonpregnant patient. If doubt exists concerning the presence or severity of mitral stenosis in the pregnant patient, cardiac catheterization can be accomplished with relative ease, utilizing adequate radiation shielding. T h e optimal time for operation is prior to the twenty-fourth week of pregnancy. This opinion is based on the fact that the maximal cardiovascular burden occurs between the twenty-eighth and thirty-second weeks of pregnancy. In most pregnant patients the choice of operative technique for mitral commissurotomy appears to be transventricular dilatation by a “closed” procedure. In this age group the use of an “open” approach would have a limited application. T h e fate of individuals with coarctation of the aorta during pregnancy is difficult to discern. According to Burwell and Metcalfe [3], “the published reports of the association of coarctation with pregnancy are biased by the dramatic catastrophes” and “the considerable number of women who go happily through pregnancy are not adequately represented in the literature.” A collected survey of 200 reported cases of coarctation during pregnancy by Mendelson revealed 40 cardiovascular complications and 14 maternal deaths [12]. In an analysis of 141 instances of dissecting aneurysm of the aorta, Schnitker and Bayer [151 found 49 cases in women of childbearing age. Fifty percent of the women were pregnant at the time of the accident, and aortic coarctation was a common underlying condition. T h e most frequent complication during pregnancy, however, is cardiac failure, and this has been observed in approximately 9% of those with coarctation [12]. In addition, Burwell and Metcalfe [3] recorded a 28% fetal mortality in patients who were treated medically. The evidence is highly suggestive that coarctation of the aorta is a serious complication of pregnancy. Our first patient with coarctation of the aorta during pregnancy was encountered in 1950, at a time when therapeutic abortion was more commonly practiced for cardiac disease. T h e discovery of a dissecting aneurysm at the time of operation was unexpected. T h e unavail-
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ability of acceptable vascular prostheses precluded any direct operative therapy at the time. T h e time of origin of the dissecting aneurysm was unknown, but the changes appeared recent. It is conceivable that aortic rupture could have occurred if pregnancy had continued. Fortunately, the patient survived the dissecting process and resection ultimately became possible. In Case 5 it was considered that elective resection of the coarctation early in pregnancy might obviate possible complications. Concern over possible rupture of the aortic aneurysm in Case 6 strongly suggested a surgical approach. T h e limited experience with resection of coarctation of the aorta during pregnancy does not permit absolute generalizations. It is our impression, however, that the gravid state should not influence the operative risk. Burwell and Metcalfe [5] have suggested that healing of an aortic anastomosis might be impaired during pregnancy. In our experience this has not been a hazard, even with the use of aortic homografts. Experience suggests that aortic surgery does not cause abortion or premature labor or have a deleterious effect upon the fetus. While the aorta is temporarily occluded during repair, the previously established collateral circulation will maintain uterine blood supply. Following adequate surgical revision of a coarctation, normotension can be expected to occur in approximately 90% of patients. Special predictable and unpredictable risks related to pregnancy and labor are associated with the presence of coarctation. Since restoration of normal blood pressure significantly reduces the hazards of heart failure and vascular accident, antepartum aortic repair appears justified. This preferably should be accomplished within the first two trimesters. T h e frequency of an isolated patent ductus arteriosus complicating pregnancy is difficult to determine. Mendelson [12] reported a collective series of 204 cases, with severe heart failure in 12 and maternal deaths in 11 patients. At the time of his report he found reports of 24 patients in which a patent ductus had been closed during pregnancy with no maternal deaths and only 1 fetal death. T h e morbidity and mortality currently associated with the division of a patent ductus arteriosus are so low that pregnancy does not appear to be a contraindication to operation. It may, in fact, be an added indication for surgery during the first two trimesters in order to avoid the potential hazards of cardiac failure and bacterial endarteritis [7, 91. Isolated atrial septal defects carry a relatively favorable prognosis. It is our impression that the incidence of atrial septal defect during pregnancy is considerably higher than could be inferred from Mendelson’s [12] collected series of 88. Most patients with atrial septal defects can tolerate comfortably the additional hemodynamic burden of pregnancy. Since effective, precise closure of atrial septal defects requires
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the use of cardiopulmonary bypass, we do not believe that the operation is ordinarily warranted during pregnancy. In our patient with an atrial septa1 defect, pregnancy was not recognized, and closure was advised because of the magnitude of the left-to-right shunt and the presence of pulmonary hypertension. Although the procedure terminated favorably for the mother and baby, it does not appear wise except under unusual circumstances. T h e use of extracorporeal circulation for the correction of cardiac lesions during pregnancy has been sporadically reported. Ueland [161 recently tabulated 11 patients who underwent surgery with extracorporeal circulation since 1958. Additional cases have been reported by Zudhi et al. [19] and Robinson and associates [14]. Our case makes a total of 14. Two maternal deaths occurred at the time of operation, and 1 death occurred 6 months postoperatively in the postpartum period. There were 5 fetal deaths, 3 due to spontaneous abortion after surgery, another due to intrapartum maternal death from operation, and the fifth due to therapeutic abortion immediately prior to operation. The hazards to the fetus in terms of death or deformity due solely to cardiopulmonary bypass are unknown. T h e pregnant patient possibly can tolerate cardiopulmonary bypass as well as the nonpregnant patient, but the fetus may not. T h e artificial oxygenation and pump activation of blood is an unphysiological process at best. T h e current use of diluents and various drugs and agents in most perfusion procedures further complicates the situation. It is also conceivable that significant fetal hypoxia could occur. For these reasons, we believe that surgical procedures necessitating the use of cardiopulmonary bypass are probably better deferred during pregnancy except for life-threatening situations. SUMMARY
T h e physiological stress of pregnancy in a patient with cardiac disease may produce cardiac decompensation. Although most patients with cardiac disease can undergo a reasonably comfortable pregnancy, those in functional Class I11 and Class IV are particularly prone to the development of cardiac failure. It is in the latter group of patients that surgical therapy during pregnancy may be most indicated. Cardiac surgery was performed during pregnancy in 9 patients. Three patients with severe mitral stenosis and congestive cardiac failure had a mitral commissurotomy in either the first or second trimester. All were significantly improved and proceeded through uneventful pregnancies and deliveries. The special problems associated with coarctation during pregnancy dictated surgical therapy in 3 patients. One patient had a therapeutic abortion prior to operation; the other 2 had 308
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normal pregnancies and deliveries following resection of the coarctation. In 2 patients, a patent ductus arteriosus was divided during the first and second trimester. Both patients had uneventful pregnancies. In another patient an atrial septa1 defect was closed with the aid of temporary cardiopulmonary bypass during the first trimester. A normal pregnancy followed. It appears that cardiac surgery during pregnancy is well tolerated and may be advantageous for selected patients under special circumstances. REFERENCES 1. Adams, J. Q. Cardiovascular physiology in normal pregnancy: Studies with the dye dilution technique. Amer. J . Obstet. Gynec. 67:741, 1954. 2. Brock, R. C. VaIvotomy in pregnancy. Proc. Roy. Soc. Med. 45:538, 1952. 3. Burwell, C. S., and Metcalfe, J. Heart Disease in Pregnancy. Boston: Little, Brown, 1958. 4. Cooley, D. A., and Chapman, D. W. Mitral commissurotomy during pregnancy. J.A.M.A. 150:1113, 1952. 5. Copeland, W. E., Wooley, D. F., Ryan, J. M., Runco, V., and Levin, H. S. Pregnancy and congenital heart disease. Amer. J . Obstet. Gynec. 86: 107, 1963. 6. Haley, H. B., and Woodbury, J. W. Body composition and body water metabolism in normal pregnancy. Surg. Gynec. Obstet. 103:227, 1956. 7. Hamilton, B. E. Cardiovascular problems in pregnancy. Circulation 9:922, 1954. 8 . Harken, D. E., and Taylor, W. J. Cardiac surgery during pregnancy. Clin. Obstet. Gynec. 4:697, 1961. 9. Kaufman, J. M., and Ruble, P. E. The current status of the pregnant cardiac. Ann. Intern. Med. 48: 1157, 1958. 10. Logan, A., and Turner, R. W. D. Mitral valvulotomy in pregnancy. Lancet 1: 1286, 1952. 11. Mason, J. In discussion of Stabler, F. E., and Szekely, P. J . Obstet. Gynaec. Brit. Emp. 59:569, 1952. 12. Mendelson, C. L. Cardiac Disease in Pregnancy: Medical Care, Cardiovascular Surgery and Obstetric Management as Related to Maternal and Fetal Welfare. Philadelphia: Davis, 1960. 13. Mendelson, C. L. Heart disease and pregnancy. Clin. Obstet. Gynec. 4:603, 1961. 14. Robinson, M., Newman, N., Creevy, D. C., Katz, J., and Harrison, D. C. Congenital aortic stenosis in pregnancy. J.A.M.A. 200: 108, 1967. 15. Schnitker, M. A., and Bayer, C. A. Dissecting aneurysm of aorta in young adults, particularly in association with pregnancy, with report of case. Ann. Intern. Med. 20:486, 1944. 16. Ueland, K. Cardiac surgery and pregnancy. Amer. J. Obstet. Gynec. 92: 148, 1965. 17. Vander Veer, J. B., and Kuo, P. T. Cardiac disease in pregnancy: A study of the patients with heart disease at the Philadelphia Lying-in Division of the Pennsylvania Hospital from 1937 to 1947, inclusive. Amer. Heart J . 39:2, 1950. 18. Walters, W. A. W., MacGregor, W. G., and Hills, M. Cardiac output at rest during pregnancy and the puerperium. Clin. Sci. 30:1, 1966. 19. Zudhi, N., Carey, J., Schmidt, A., and Greer, A. Total body perfusion and pregnancy. J. Int. Coll. Surg. 43:43, 1965.
COLLINS, DANIEL, AND SCOTT EDITORIAL BOARD COMMENT Since there is no evidence that Class I or I1 cardiac patients require surgical intervention during pregnancy, only the 3 patients with symptomatic mitral stenosis reported in this article were valid candidates for cardiac surgery. Certainly, an asymptomatic patient with a patent ductus arteriosus, a coarctation, or an interatrial septa1 defect does not require operation during pregnancy.
NOTICE FROM THE SOCIETY OF THORACIC SURGEONS The Fourth Annual Meeting of The Society of Thoracic Surgeons was held in New Orleans, Louisiana, January 29-31, 1968. Innovations in the scientific program this year were the Presidential Address, the address by an honored guest, and the surgical motion picture session. The second postgraduate lecture series was held on January 28 with 211 members and guests attending. At the annual business session the following officers were elected: Lyman A. Brewer 111, President; J. Maxwell Chamberlain, Vice-president; and John N. Briggs, Councilor. Reelected were F. X. Byron, Secretary; Robert G. Ellison, Treasurer; and John D. Steele, Editor. Elected to Honorary Membership was Mr. Donald Ross of London, England. Fifty-five new members were elected, increasing total membership to 710. The Society adopted a resolution recommending to the Hon. Harley 0. Staggers that HR-6165 be brought to a hearing and that a member of the Society be allowed to testify. This bill relates to control of medical devices. The Society also approved a resolution deploring the release of scientific information to the public news media before being subjected to critical review at a scientific meeting. Dues of the Society are to remain unchanged (at $25.00), although the monthly publication of T h e Annals of Thoracic Surgery has resulted in a subscription price, to the Society, of $19.00. More than 800 physicians registered for the session. Total attendance, including exhibitors and wives, exceeded 1200. Members are reminded at this time that the deadline for receipt of abstracts for the 1969 meeting is September 15, 1968. The original and 8 copies should be sent to the Secretary. All applications for membership (together with letters of recommendation) must be submitted by October 1, 1968. The next meeting of the Society will be held at the Hilton Inn, San Diego, California, January 27-29, 1969. F. X. BYRON, SECRETARY
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ardiac disease is currently one of the most frequent causes of maternal disability and death. Significant improvements in the obstetrical management of toxemia, infection, and hemorrhage have enhanced the relative importance of cardiac disease during pregnancy. T h e recorded incidence of cardiac disease in pregnancy in several large series varies from 1.5 to 3.7% [13, 171. Rheumatic heart disease accounts for approximately 90% of the organic cardiac lesions encountered during pregnancy. Mendelson’s collected report of 3,353 pregnancies complicated by rheumatic valvular disease showed 75% to have dominant mitral stenosis, 10 to 15% combined mitral and aortic lesions, and the remainder to have other valvular problems [12]. Mitral stenosis is therefore the most significant acquired valvular lesion encountered during pregnancy. Congenital heart disease is present in 7 to S%, and the remainder is composed of hypertensive and miscellaneous cardiac conditions. Associated pregnancy was previously considered one of the contraindications to surgery for heart disease. Within the last decade, however, surgical therapy for cardiac disease during pregnancy has been utilized with increasing frequency. Most of the surgical experience has been with mitral stenosis, since this is the cardiac lesion most frequently coexisting with pregnancy and an adequate operation has been available for several years. Surgical therapy recently has been used increasingly for other acquired and congenital cardiac lesions during pregnancy. Mendelson has stated that no evidence exists that the gravid state increases operative risks or that antepartum cardiovascular surgery jeopardizes the unborn baby [12]. If this is clearly the case, more frequent and effective use of cardiac surgery during pregnancy can be anticipated. During the last several years we have had the opportunity to participate in the surgical care of 9 patients with cardiac disease during pregnancy. This experience forms the basis for this report. From the Department of Surgery, Vanderbilt University Medical Center, Nashville, Tenn. Supported in part by U.S. Public Health Service Grant HE 08195. Presented at the Fourteenth Annual Meeting of the Southern Thoracic Surgical Association, Dallas, Tex., Nov. 9-11, 1967.
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Cardiac Surgery During Pregnancy PHYSIOLOGICAL CHANGES IN N O R M A L PREGNANCY
Several physiological events occur during the course of normal pregnancy [l, 3, 6, 121. Among the more significant is a gradual increase in oxygen consumption beginning at about the end of the first trimester and attaining a maximum at term. The pulse rate usually increases gradually, starting at about the tenth week and achieving a maximum at about the thirtieth week. The usual increase is 10 to 15 beats per minute. T h e systolic blood pressure normally remains stable, whereas the diastolic pressure may decrease due to a diminished peripheral resistance. T h e cardiac output also increases to a maximum level at about the thirtieth week. Some recent evidence indicates that the cardiac output may be significantly increased during the first trimester [18]. T h e cardiac output may be increased 30 to 50% at its maximum. Blood volume is also maximally increased at the eighth month due to an increase in both red cell mass and plasma volume. T h e increase in plasma volume is proportionately greater, resulting in a reduced hematocrit. Total body water is maximally increased at term and is usually 15 to 20% greater than normal. Alterations in blood volume play an important role in the patterns of cardiac output and related phenomena, but the placenta may also function as an arteriovenous fistula. A return to the normal nonpregnant state is achieved by the second postpartum week. T h e physiological aberrations exhibited during normal pregnancy can easily be misinterpreted as signs of organic heart disease. Increased venous pressure, edema, capillary pulsation, transient basilar rales, systolic murmurs, split and accentuated heart sounds, and changes in cardiac contour and electrocardiographic patterns may all accompany normal pregnancy. It is thus occasionally hazardous to first make the diagnosis of cardiac disease during pregnancy in the absence of definitive signs. CASE REPORTS MITRAL STENOSIS
Case 1 . A 22-year-oldwhite woman entered Vanderbilt University Hospital for the first time on August 1, 1955, complaining of shortness of breath. She was in the fifth month of pregnancy. She had delivered a viable infant 8 months before admission, but had been in severe cardiac failure during the last trimester. For 2 months preceding the current hospitalization, she had been severely dyspneic with any exertion, had two pillow orthopnea, and repeated episodes of hemoptysis. The clinical findings were compatible with severe mitral stenosis. A mitral commissurotomy was accomplished. She tolerated the operation well and proceeded through pregnancy without significant difficulty. A normal infant was born 4 months postoperatively. Seven years later recurrent mitral stenosis necessitated a second commissurotomy which was well tolerated. Case 2. A 19-year-oldwhite woman in the fourth month of pregnancy and
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COLLINS, DANIEL, AND SCOTT in congestive cardiac failure was admitted to Vanderbilt University Hospital on August 2, 1961. Approximately 3 months previously she had developed acute pulmonary edema, hemoptysis, and paroxysmal nocturnal dyspnea. Despite digitalis administration she continued to have severe symptoms. All the clinical findings were compatible with mitral stenosis. She tolerated mitral commissurotomy well. Her pregnancy postoperatively was uncomplicated, and she delivered a normal infant 5 months postoperatively. Case 3. A 35-year-old white woman was admitted to Vanderbilt University Hospital on July 24, 1961, complaining of weakness and shortness of breath. She was in the second month of pregnancy. The presence of mitral stenosis had been known for 12 years. She previously had uneventful pregnancies in 1945 and 1959. At the time of admission the findings were compatible with mitral stenosis, atrial fibrillation, and congestive cardiac failure. After digitalis administration, catheterization of the left side of the heart was accomplished and demonstrated severe mitral stenosis. Mitral commissurotomy was performed without complication. In the postoperative period a normal sinus rhythm was restored. Pregnancy continued uneventfully, and a normal infant was delivered 7 months later. Two days following delivery cerebral embolization occurred, with a transient hemiparesis. She subsequently did well with no residual weakness. COARCTATION OF THE AORTA
Case 4. A 27-year-old white woman in the second month of pregnancy was admitted to Vanderbilt University Hospital on February 20, 1950, because of hypertension. The patient's first knowledge of hypertension was in 1944, at the age of 21, during her first pregnancy. During this pregnancy she apparently had a greatly elevated blood pressure, edema, shortness of breath, headaches, and blind spots before her eyes. Since that time, her blood pressure had been elevated on all examinations. Three kidney stones were removed in 1945. At the time of her admission she was 2 months pregnant. Her blood pressure was 170/100 mm. Hg. All of the physical findings were compatible with coarctation of the aorta. A retrograde aortogram revealed a well-defined coarctation. In view of the difficulty that the patient had experienced with her previous pregnancy, therapeutic abortion was accomplished on March 4, 1950. On March 10, 1950, a left thoracotomy was performed. An extensive amount of reaction was present about the aorta. The reaction was so striking about the proximal segment of aorta that it appeared dangerous to apply clamps. The left subclavian artery was accordingly divided preparatory to establishing a subclavian anastomosis to the aorta distal to the coarctation. After division of the subclavian artery, it was evident that a dissecting aneurysm was present. It did not appear possible to surgically alleviate the coarctation and thoracotomy closure was accomplished. The patient tolerated the procedure well, and the postoperative course was uncomplicated. The patient was subsequently admitted to Vanderbilt University Hospital on December 1, 1957, with a history of increasing dyspnea and precordial pain for the previous year. At this time the blood pressure in the right arm was 190/90 mm. Hg. The physical examination was otherwise essentially unchanged. A left thoracotomy was performed on December 5, 1957. At this operation it was possible to resect the coarctation including the left subclavian artery and replace the resected segment with an aortic homograft. She tolerated the operation well and her postoperative period was relatively smooth. She was next admitted to the hospital on July 1, 1962. In the interim she had done extremely well. She had no limitation of activity and was on no medication. Blood pressure in the right arm was 120/85 mm. Hg. A retrograde aortogram was performed which demonstrated a widely patent graft without evidence of any degenerative change. Case 5. A 16-year-old white girl was admitted to Vanderbilt University
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Cardiac Surgery During Pregnancy Hospital on August 7, 1953, because of high blood pressure. One month before admission the patient experienced sharp, crushing precordial pain and thereafter had a hysterical episode. She had been hospitalized and found to have high blood pressure; the blood pressure in the arms was 180190 mm. Hg. She had findings typical of a coarctation of the aorta. In addition, her uterus was enlarged to about the size of a two-month pregnancy. An electrocardiogram was considered to be within normal limits. A chest x-ray revealed notching of the ribs posteriorly. The heart did not appear to be enlarged. An Ascheim-Zondek test confirmed the presence of pregnancy. On August 15, 1953, resection of the coarctation and primary anastomosis were accomplished without difficulty. The postoperative period was essentially uneventful. Postoperatively the blood pressure stabilized at about 140190 mm. Hg. She proceeded through pregnancy without difficulty and delivered a healthy, viable infant 7 months postoperatively. Case 6. A 31-year-old white woman in the third month of pregnancy was admitted to Vanderbilt University Hospital for the first time on May 5, 1956. For 2 to 3 months before admission she had noted increasing weakness and easy fatigability. Hypertension had been discovered 7 years previously during her second pregnancy. She had apparently gone through two previous pregnancies without difficulty. On examination the blood pressure in the upper extremities was 185190 mm. Hg. The pulses in the legs were extremely weak. Routine clinical laboratory data were within normal limits. An electrocardiogram was interpreted as being normal. On a chest film an aneurysm of the descending thoracic aorta was apparent. An aortogram demonstrated a severe coarctation immediately distal to the origin of the left subclavian artery and an 8 cm. aortic aneurysm just beyond the coarctation. On May 21, 1956, the coarctation and the aneurysm were excised and replaced with a freeze-dried aortic homograft. Postoperatively she did quite well without significant difficulty. She proceeded through her pregnancy without any significant difficulty. The blood pressures were usually in the range of 120-130/70 mm. Hg. A normal infant was born in September, 1956. She was readmitted to this hospital in 1962, at which time a retrograde thoracic aortogram was obtained. This revealed a normally functioning aortic homograft. PATENT DUCTUS ARTERIOSUS
Case 7. A 19-year-old white woman in the second month of pregnancy was admitted to Vanderbilt University Hospital on October 2, 1963, for investigation of a cardiac murmur. A murmur had been known since shortly after birth. The patient had been essentially asymptomatic throughout life. On examination the blood pressure was 120/40 mm. Hg. She was a well-developed young female in no distress. A continuous murmur was localized over the second and third intercostal spaces. The routine clinical laboratory data were within normal limits. An immunological test for pregnancy was positive. Cardiac catheterization was accomplished on October 3, 1963, and revealed a patent ductus arteriosus. A patent ductus, 12 mm. in diameter, was divided on October 8, 1963. Her postoperative convalescence was entirely uneventful, and she subsequently delivered a normal infant. Case 8. A 22-year-old white woman entered Vanderbilt University Hospital for the second time on June 16, 1961. This patient had previously been admitted on January 12, 1961, with subacute bacterial endarteritis superimposed on a patent ductus arteriosus. She had known of a murmur all of her life. She had previously had one normal pregnancy. At the time of her previous hospitalization she had received intravenous penicillin therapy for 6 weeks, with apparent cure of the bacterial endarteritis. It had been planned that the patient have cardiac catheterization, followed by division of the patent ductus arteriosus. Following her discharge, however, she had become pregnant and was admitted on June 16 VOL.
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COLLINS, DANIEL, AND SCOTT about 2% months pregnant. All of her physical findings were compatible with a patent ductus arteriosus. The routine clinical laboratory data were within normal limits. An electrocardiogram suggested left ventricular hypertrophy. A patent ductus arteriosus, 10 mm. in diameter, was divided on June 26, 1961. The patient tolerated the procedure well, and the postoperative convalescence was uneventful. She was discharged from the hospital and proceeded through an uneventful pregnancy with the delivery of a normal infant approximately 6 months later. ATRIAL SEPTAL DEFECT
Case 9. A 22-year-old white woman was admitted to Vanderbilt University Hospital for a heart operation on June 23, 1962. She had previously been admitted in January, 1958, with a coarctation of the aorta. Cardiac catheterization at that time had revealed a pulmonary artery systolic pressure of approximately 100 mm. Hg; the brachial arterial systolic pressure was approximately 200 mm. Hg. Operation was performed on January 13, 1958, at which time a coarctation was excised and a patent ductus divided. An aortic homograft was anastomosed between the two ends of the aorta. Postoperatively she did well and had little subsequent difficulty. She was subsequently readmitted to the hospital in 1962. At that time she was normotensive. She continued to have an audible systolic murmur. A retrograde aortogram demonstrated a normally functioning aortic homograft. Cardiac catheterization was accomplished and demonstrated an atrial septal defect. The pulmonary artery pressure at this time was approximately 50120 mm. Hg. During cardiopulmonary bypass on June 26, 1962, an ostium secundum type of atrial septal defect approximately 2 x 3 cm. was closed. The patient tolerated the operation well, and her postoperative period was essentially uncomplicated. It was not known until postoperatively that she was in the second month of pregnancy at the time of operation. She proceeded through a normal pregnancy and delivery of a normal infant. DISCUSSION
The precise role of cardiac surgery during pregnancy is still evolving. Certainly the majority of women with cardiac disease can and do proceed through pregnancy with medical management. Admirably low rates for maternal mortality have been reported in large series of patients with pregnancies complicated by cardiac disease. Burwell and Metcalfe [3] reported a mortality rate of 1.O% in 298 patients with heart disease during pregnancy. A maternal mortality of 0.8% was described by Mendelson [13] in a group of 3,690 pregnancies complicated by heart disease. From such data it has been concluded erroneously that cardiac disease is well tolerated during pregnancy by all patients. It is clear, however, that the majority of patients in these series had mild forms of cardiac disease with little functional limitation. Functional classification according to the New York Heart Association’s criteria provides the most reliable prognostic information with regard to risk for the pregnant patient with cardiac disease. Those patients in Class I and Class I1 tolerate the hemodynamic burden of pregnancy without serious difficulty. Most of the mortality occurs in Class I11 and Class IV patients, and in reported series has varied from 4.2 to 18.7% [3, 171. It 304
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is also well documented that heart failure is the major cause of maternal death in cardiac subjects and that the onset of decompensation and time of death are related to the hemodynamic burden of pregnancy D31. We are in accord with the view of Harken and Taylor [8] who have stated that “physicians and surgeons alike would prefer to avoid any and all intrapartum operations. Surgery should be undertaken only when it is clear that the result desired can be best attained by an operation and the risks are acceptable.” Much of the controversy regarding cardiac surgery during pregnancy relates to a definition of the risks involved, both to the mother and the fetus. T h e most extensive and convincing data are those concerned with mitral commissurotomy during pregnancy. Brock [21, Cooley and Chapman [41, Logan and Turner [lo], and Mason [ l l ] reported in 1952 on a total of 11 patients who underwent mitral commissurotomy during pregnancy, with one maternal death and one premature delivery. In 1965 Ueland [16] reported on a collected series of 5 14 patients in whom mitral commissurotomy had been performed during pregnancy. Most patients were in Class I11 and Class IV. In the entire series there were a total of 9 maternal deaths (1.8%) and 44 fetal deaths (8.6%).A comparison of similar Class 111 and Class IV patients treated medically reveals a maternal mortality of 4.2 to 18.7% and a fetal mortality of up to 50%. It is tempting to attribute the relatively low mortality in the patients having commissurotomy solely to the excellence of surgical management. It is recognized, however, that such results are possible only with cooperative and enlightened medical participation. Upon the basis of our own limited experience and the collected experiences of others, it appears that mitral commissurotomy during pregnancy is an acceptable procedure from the standpoint of maternal and fetal mortality. From the reported statistics the mortality is considerably less in those Class I11 and Class IV patients who are treated surgically than in those receiving intensive medical management. In fact, the mortality for mitral commissurotomy during pregnancy is significantly less than that reported for comprehensive series of patients having mitral commissurotomy in the nongravid state. The reasons for this are readily apparent. T h e majority of pregnant patients with mitral stenosis are in the second and third decades of life and usually have not developed atrial fibrillation, advanced cardiac decompensation or heavily calcified valves. In our experience these conditions have been associated with the greatest morbidity and mortality following mitral commissurotomy and are ordinarily encountered in an older age group. Even if the mortality for mitral commissurotomy during pregnancy can be demonstrated to be acceptably low, the procedure would VOL.
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have little relevance if the patient’s clinical condition were not significantly benefited. It is our impression from our limited experience, as well as that of others [S], that a gratifying response occurs in most pregnant patients following mitral commissurotomy. T h e manifestations of cardiac failure are quickly relieved and the medical management of the continuing pregnancy is greatly simplified. Mitral commissurotomy is a palliative procedure, and reoperation may ultimately be necessary, as exemplified by our Case 1. It does not appear rational, however, to preclude the initial operation upon the basis of possible recurrent difficulties. In our opinion the indications for mitral commissurotomy in the pregnant patient are probably the same as in the nonpregnant patient. If doubt exists concerning the presence or severity of mitral stenosis in the pregnant patient, cardiac catheterization can be accomplished with relative ease, utilizing adequate radiation shielding. T h e optimal time for operation is prior to the twenty-fourth week of pregnancy. This opinion is based on the fact that the maximal cardiovascular burden occurs between the twenty-eighth and thirty-second weeks of pregnancy. In most pregnant patients the choice of operative technique for mitral commissurotomy appears to be transventricular dilatation by a “closed” procedure. In this age group the use of an “open” approach would have a limited application. T h e fate of individuals with coarctation of the aorta during pregnancy is difficult to discern. According to Burwell and Metcalfe [3], “the published reports of the association of coarctation with pregnancy are biased by the dramatic catastrophes” and “the considerable number of women who go happily through pregnancy are not adequately represented in the literature.” A collected survey of 200 reported cases of coarctation during pregnancy by Mendelson revealed 40 cardiovascular complications and 14 maternal deaths [12]. In an analysis of 141 instances of dissecting aneurysm of the aorta, Schnitker and Bayer [151 found 49 cases in women of childbearing age. Fifty percent of the women were pregnant at the time of the accident, and aortic coarctation was a common underlying condition. T h e most frequent complication during pregnancy, however, is cardiac failure, and this has been observed in approximately 9% of those with coarctation [12]. In addition, Burwell and Metcalfe [3] recorded a 28% fetal mortality in patients who were treated medically. The evidence is highly suggestive that coarctation of the aorta is a serious complication of pregnancy. Our first patient with coarctation of the aorta during pregnancy was encountered in 1950, at a time when therapeutic abortion was more commonly practiced for cardiac disease. T h e discovery of a dissecting aneurysm at the time of operation was unexpected. T h e unavail-
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ability of acceptable vascular prostheses precluded any direct operative therapy at the time. T h e time of origin of the dissecting aneurysm was unknown, but the changes appeared recent. It is conceivable that aortic rupture could have occurred if pregnancy had continued. Fortunately, the patient survived the dissecting process and resection ultimately became possible. In Case 5 it was considered that elective resection of the coarctation early in pregnancy might obviate possible complications. Concern over possible rupture of the aortic aneurysm in Case 6 strongly suggested a surgical approach. T h e limited experience with resection of coarctation of the aorta during pregnancy does not permit absolute generalizations. It is our impression, however, that the gravid state should not influence the operative risk. Burwell and Metcalfe [5] have suggested that healing of an aortic anastomosis might be impaired during pregnancy. In our experience this has not been a hazard, even with the use of aortic homografts. Experience suggests that aortic surgery does not cause abortion or premature labor or have a deleterious effect upon the fetus. While the aorta is temporarily occluded during repair, the previously established collateral circulation will maintain uterine blood supply. Following adequate surgical revision of a coarctation, normotension can be expected to occur in approximately 90% of patients. Special predictable and unpredictable risks related to pregnancy and labor are associated with the presence of coarctation. Since restoration of normal blood pressure significantly reduces the hazards of heart failure and vascular accident, antepartum aortic repair appears justified. This preferably should be accomplished within the first two trimesters. T h e frequency of an isolated patent ductus arteriosus complicating pregnancy is difficult to determine. Mendelson [12] reported a collective series of 204 cases, with severe heart failure in 12 and maternal deaths in 11 patients. At the time of his report he found reports of 24 patients in which a patent ductus had been closed during pregnancy with no maternal deaths and only 1 fetal death. T h e morbidity and mortality currently associated with the division of a patent ductus arteriosus are so low that pregnancy does not appear to be a contraindication to operation. It may, in fact, be an added indication for surgery during the first two trimesters in order to avoid the potential hazards of cardiac failure and bacterial endarteritis [7, 91. Isolated atrial septal defects carry a relatively favorable prognosis. It is our impression that the incidence of atrial septal defect during pregnancy is considerably higher than could be inferred from Mendelson’s [12] collected series of 88. Most patients with atrial septal defects can tolerate comfortably the additional hemodynamic burden of pregnancy. Since effective, precise closure of atrial septal defects requires
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the use of cardiopulmonary bypass, we do not believe that the operation is ordinarily warranted during pregnancy. In our patient with an atrial septa1 defect, pregnancy was not recognized, and closure was advised because of the magnitude of the left-to-right shunt and the presence of pulmonary hypertension. Although the procedure terminated favorably for the mother and baby, it does not appear wise except under unusual circumstances. T h e use of extracorporeal circulation for the correction of cardiac lesions during pregnancy has been sporadically reported. Ueland [161 recently tabulated 11 patients who underwent surgery with extracorporeal circulation since 1958. Additional cases have been reported by Zudhi et al. [19] and Robinson and associates [14]. Our case makes a total of 14. Two maternal deaths occurred at the time of operation, and 1 death occurred 6 months postoperatively in the postpartum period. There were 5 fetal deaths, 3 due to spontaneous abortion after surgery, another due to intrapartum maternal death from operation, and the fifth due to therapeutic abortion immediately prior to operation. The hazards to the fetus in terms of death or deformity due solely to cardiopulmonary bypass are unknown. T h e pregnant patient possibly can tolerate cardiopulmonary bypass as well as the nonpregnant patient, but the fetus may not. T h e artificial oxygenation and pump activation of blood is an unphysiological process at best. T h e current use of diluents and various drugs and agents in most perfusion procedures further complicates the situation. It is also conceivable that significant fetal hypoxia could occur. For these reasons, we believe that surgical procedures necessitating the use of cardiopulmonary bypass are probably better deferred during pregnancy except for life-threatening situations. SUMMARY
T h e physiological stress of pregnancy in a patient with cardiac disease may produce cardiac decompensation. Although most patients with cardiac disease can undergo a reasonably comfortable pregnancy, those in functional Class I11 and Class IV are particularly prone to the development of cardiac failure. It is in the latter group of patients that surgical therapy during pregnancy may be most indicated. Cardiac surgery was performed during pregnancy in 9 patients. Three patients with severe mitral stenosis and congestive cardiac failure had a mitral commissurotomy in either the first or second trimester. All were significantly improved and proceeded through uneventful pregnancies and deliveries. The special problems associated with coarctation during pregnancy dictated surgical therapy in 3 patients. One patient had a therapeutic abortion prior to operation; the other 2 had 308
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normal pregnancies and deliveries following resection of the coarctation. In 2 patients, a patent ductus arteriosus was divided during the first and second trimester. Both patients had uneventful pregnancies. In another patient an atrial septa1 defect was closed with the aid of temporary cardiopulmonary bypass during the first trimester. A normal pregnancy followed. It appears that cardiac surgery during pregnancy is well tolerated and may be advantageous for selected patients under special circumstances. REFERENCES 1. Adams, J. Q. Cardiovascular physiology in normal pregnancy: Studies with the dye dilution technique. Amer. J . Obstet. Gynec. 67:741, 1954. 2. Brock, R. C. VaIvotomy in pregnancy. Proc. Roy. Soc. Med. 45:538, 1952. 3. Burwell, C. S., and Metcalfe, J. Heart Disease in Pregnancy. Boston: Little, Brown, 1958. 4. Cooley, D. A., and Chapman, D. W. Mitral commissurotomy during pregnancy. J.A.M.A. 150:1113, 1952. 5. Copeland, W. E., Wooley, D. F., Ryan, J. M., Runco, V., and Levin, H. S. Pregnancy and congenital heart disease. Amer. J . Obstet. Gynec. 86: 107, 1963. 6. Haley, H. B., and Woodbury, J. W. Body composition and body water metabolism in normal pregnancy. Surg. Gynec. Obstet. 103:227, 1956. 7. Hamilton, B. E. Cardiovascular problems in pregnancy. Circulation 9:922, 1954. 8 . Harken, D. E., and Taylor, W. J. Cardiac surgery during pregnancy. Clin. Obstet. Gynec. 4:697, 1961. 9. Kaufman, J. M., and Ruble, P. E. The current status of the pregnant cardiac. Ann. Intern. Med. 48: 1157, 1958. 10. Logan, A., and Turner, R. W. D. Mitral valvulotomy in pregnancy. Lancet 1: 1286, 1952. 11. Mason, J. In discussion of Stabler, F. E., and Szekely, P. J . Obstet. Gynaec. Brit. Emp. 59:569, 1952. 12. Mendelson, C. L. Cardiac Disease in Pregnancy: Medical Care, Cardiovascular Surgery and Obstetric Management as Related to Maternal and Fetal Welfare. Philadelphia: Davis, 1960. 13. Mendelson, C. L. Heart disease and pregnancy. Clin. Obstet. Gynec. 4:603, 1961. 14. Robinson, M., Newman, N., Creevy, D. C., Katz, J., and Harrison, D. C. Congenital aortic stenosis in pregnancy. J.A.M.A. 200: 108, 1967. 15. Schnitker, M. A., and Bayer, C. A. Dissecting aneurysm of aorta in young adults, particularly in association with pregnancy, with report of case. Ann. Intern. Med. 20:486, 1944. 16. Ueland, K. Cardiac surgery and pregnancy. Amer. J. Obstet. Gynec. 92: 148, 1965. 17. Vander Veer, J. B., and Kuo, P. T. Cardiac disease in pregnancy: A study of the patients with heart disease at the Philadelphia Lying-in Division of the Pennsylvania Hospital from 1937 to 1947, inclusive. Amer. Heart J . 39:2, 1950. 18. Walters, W. A. W., MacGregor, W. G., and Hills, M. Cardiac output at rest during pregnancy and the puerperium. Clin. Sci. 30:1, 1966. 19. Zudhi, N., Carey, J., Schmidt, A., and Greer, A. Total body perfusion and pregnancy. J. Int. Coll. Surg. 43:43, 1965.
COLLINS, DANIEL, AND SCOTT EDITORIAL BOARD COMMENT Since there is no evidence that Class I or I1 cardiac patients require surgical intervention during pregnancy, only the 3 patients with symptomatic mitral stenosis reported in this article were valid candidates for cardiac surgery. Certainly, an asymptomatic patient with a patent ductus arteriosus, a coarctation, or an interatrial septa1 defect does not require operation during pregnancy.
NOTICE FROM THE SOCIETY OF THORACIC SURGEONS The Fourth Annual Meeting of The Society of Thoracic Surgeons was held in New Orleans, Louisiana, January 29-31, 1968. Innovations in the scientific program this year were the Presidential Address, the address by an honored guest, and the surgical motion picture session. The second postgraduate lecture series was held on January 28 with 211 members and guests attending. At the annual business session the following officers were elected: Lyman A. Brewer 111, President; J. Maxwell Chamberlain, Vice-president; and John N. Briggs, Councilor. Reelected were F. X. Byron, Secretary; Robert G. Ellison, Treasurer; and John D. Steele, Editor. Elected to Honorary Membership was Mr. Donald Ross of London, England. Fifty-five new members were elected, increasing total membership to 710. The Society adopted a resolution recommending to the Hon. Harley 0. Staggers that HR-6165 be brought to a hearing and that a member of the Society be allowed to testify. This bill relates to control of medical devices. The Society also approved a resolution deploring the release of scientific information to the public news media before being subjected to critical review at a scientific meeting. Dues of the Society are to remain unchanged (at $25.00), although the monthly publication of T h e Annals of Thoracic Surgery has resulted in a subscription price, to the Society, of $19.00. More than 800 physicians registered for the session. Total attendance, including exhibitors and wives, exceeded 1200. Members are reminded at this time that the deadline for receipt of abstracts for the 1969 meeting is September 15, 1968. The original and 8 copies should be sent to the Secretary. All applications for membership (together with letters of recommendation) must be submitted by October 1, 1968. The next meeting of the Society will be held at the Hilton Inn, San Diego, California, January 27-29, 1969. F. X. BYRON, SECRETARY
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