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Myxoma of the Atrium: Successful Surgical Treatment in Two Cases
Myxoma of the Atrium: Successful Surgical Treatment in Two Cases F. HENRY ELLIS, Jlt. HAROLD 1". lVIANKIN HOWARD
T~. ]~URCH:EI~L
tumors of the heart are not encountered frequently and are rarely diagnosed before death. Myxoma of the heart comprises about 50 per cent of all primary cardiac tumors and is being recognized more frequently, particularly during left atrial explorations in patients suspected of having mitral stenosis. Efforts to establish the diagnosis clinically should be encouraged for this is a benign curable lesion. Advances in open heart surgery now allow complete removal of an intracavitary myxoma of the atrium with restoration of the hemodynamics. The purpose of this paper is to present our surgical experience with this condition. The cases of two patients who underwent successful surgical excision of atrial myxomas are reported. In one patient (Case I), the tumor was located in the left atrium; in the other (Case 11), it was located in the right atrium. PRIMARY
REPORT OF CASES
Clinical Features CASE T. * A 45-year-old woman was referred to the Clinic with a history of weakness and exhaustion of 7 years' duration. For the previous 14 months, she had had repeated episodes of "dizzy spells" and had been troubled by palpitation and dyspnea on exertion. One year previously she had undergone a minor operation on the scalp elsewhere, followed in 4 days by fever, sore throat, arthralgia, myalgia and diffuse pain in the anterior region of the thorax. A diagnosis of acute rheumatic fever or bacterial endocarditis had been entertained. Seven months before coming to the Clinic her home physician had made a diagnosis of probable rheumatic mitral valvulitis with mitral stenosis. Four months before examination she had had a period of unconsciousness lasting 48 hours with partial right hemiparesis suggesting an embolic event. Subsequently, she"lacked
* Case I is included through the courtesy of Dr. John W. Kirklin. We are indebted to Dr. Morgan Matthews, Shreveport, Louisiana, for referral of this patient. 1087
1088 F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
Fig. 139 (Case I). a, Postero-anterior view of thorax. b, Lateral view.
stamina, experienced subjective palpitation episodically and exhibited moderate postural hypotension. On examination she appeared pale and chronically ill. There was no distention of the veins in the neck and the blood pressure was 90 mm. of mercury systolic and 60 mm. diastolic. A diffuse apical beat was noted from the left nipple to the sternum. The pulmonic second sound was accentuated, grade 2, and the mitral first sound was narrowly split and accentuated, grade 4. A third apical heart sound that did not seem to be an "opening snap" and an apical systolic murmur, grade 2, were heard, but at no time was an apical diastolic murmur audible. The left border of cardiac dullness was in the anterior axillary line. Hepatomegaly or other physical findings of note were absent save for mild residual neurologic deficit of a left cerebral infarct. The laboratory data including determination of hemoglobin, leukocyte count and differential leukocyte counts, value for urea and results of urinalysis, and the Kline test were negative or normal. The sedimentation rate was 51 mm. in 1 hour (Westergren method). The thoracic roentgenogram and cardiac fluoro~copic views (Fig. 139, a, b) revealed moderate cardiac enlargement. Calcification of the mitral valve was not apparent. The electrocardiograms showed low voltage in the standard and unipolar limb leads and inversion of the T wave V-I through V-3. Changes in body position and mild exertion precipitated the appearance of bigeminy related to alternate premature ventricular contractions. A clinical diagnosis of mitral stenosis was entertained, but the natural history of the patient's disease was regarded as highly atypical. The diagnosis of atrial myxoma was given priority in the clinical appraisal. Catheterization of the right side of the heart was undertaken in the hope of resolving the enigma. The findings were a low cardiac index (2.1 liters per minute per square meter), no evidence of an intracardiac shunt and elevated pressures in the right ventricle (61 mm. of mercury systolic and 6 mm. diastolic) , pulmonary artery (61/28) and in the pulmonary artery wedge position (34/15). The "wedge" pressure pulse contour revealed a prominent V wave. The mixed venous saturation (pulmonary) was 66 per cent by Van Slyke analysis.
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The pressures were noted to fluctuate over a considerable range which occurred at the several sites in an irregular but cyclic manner. These undulations of pressure were not synchronous with respirations, alterations in basic cardiac rhythm, or body position. Pressures were observed to fluctuate on occasions, in the pulmonary trunk and right ventricle between 50/21 to 90/30 and 53/4 to 90/0, respectively. The peak of the "V wave" in the wedge contour was likewise noted to range from 25 to 40. These variations were interpreted as further evidence of intermittent and varying degrees of obstruction to left atrial outflow. The very high V wave in the pulmonary artery wedge pressure would place this patient in the group of patients with predominant mitral regurgitation, if interpreted in the light of our experience. 6 Indicator-dilution curves recorded with the use of cuvette oximeter sampling at the radial artery with injections of T-1824 into the pulmonary trunk and superior vena cava were productive of time components essentially normal for these injection sites. The secondary peak in dye concentration in the curves, indicating systemic recirculation of the indicator, were regarded as minimal in amplitude and consistent with a reduced cardiac output. However, an apparent disparity existed between the anticipated degree of mitral insufficiency on inspection of the contour of the pulmonary artery wedge pressure pulse6 and that indicated by study of the after portion of the dye-dilution curves. * 18, 19 It might be reasoned that the dilution curve was nearly normal by virtue of the rapid washout characteristics of a normal-sized left atrium whose volume was reduced by a space-occupying lesion. Whereas, the usual case of mitral disease with an inordinately high "V wave" in the "wedge" contour may be expected to exhibit a greatly distorted disappearance slope of the dye curve owing to the slow washout characteristics of a large-volume left atrium and a markedly regurgitant mitral valve. It also may be conjectured that the atrial tumor was pushed in a retrograde direction to obstruct the pulmonary veins in systole or to act as a piston in the left atrium. A venous angiocardiogram was made, but it failed to show evidence of the tumor. Exploratory cardiotomy without the cardiac bypass was undertaken because, statistically, mitral stenosis seemed more likely than atrial tumor and the angiocardiogram had not allowed visualization of a tumor. Palpation within the left atrium revealed a powerful regurgitant jet of blood from the left ventricle and a smooth, rubbery tumor the size of a golf ball in the left atrium. The incision was closed. Seven days later the patient was reoperated on through an anterior thoracotomy incision. The left subclavian artery and the venae cavae were cannulated and extracorporeal circulation was instituted. The left atrium was approached by opening the right atrium and incising the atrial septum. A tumor, measuring 5 by 4 cm. and weighing 34 grams, was found attached to the atrial septum above the mitral valve (Fig. 140). A tongue of the tumor was wedged into the posteromedial commissure of the mitral valve and was responsible for mitral insufficiency. The tumor was completely removed in several pieces. The atrial septum was closed, as was the wall of the right atrium, and extracorporeal circulation was discontinued after 30 minutes. A grade 2 regurgitant jet of blood could still
* We are indebted to Dr. E. H. Wood for making available the data gathered in the cardiac catheterization laboratory on Case 1. The apparent disparity between the dye-dilution curves and the pulmonary artery wedge pressure pulse contours is being studied in this laboratory. Studies, carried out on a schema simulating the central circulation, indicate that the characteristics of the indicator-dilution curve in mitral insufficiency are greatly influenced by the volume of the left atrial chamber. 1O
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F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
Fig. 140 (Case I). a, Appearance of cut surface of left atrial myxoma. b, Microscopic appearance of tumor. Individual cells surrounded by mucous material. Pattern reminiscent of chondrocytes (hematoxylin and eosin; X200).
be felt in the left atrium, probably due to dilatation of the mitral ring. vVhereas pressure in the right pulmonary vein recorded before removal was 68/14, after removal it had dropped to 18/8. The patient made a slo\v but uneventful postoperative recovery and was dismissed from the hospital to her home on the twenty-seventh day. When last heard from, 5 months after operation, her cardiovascular status was excellent but she was troubled by some functional complaints. CASE 11. A 48-year-old draftsman was referred to the Clinic for excision of a tumor within the right atrium. The diagnosis had been made at another institution after exploration for suspected tricuspid stenosis. * The patient dated his
* We are indebted to Drs. Jean de L. Mignault and Edouard S. Gagnon of Montreal, Canada, and to Dr. Thomas J. Quiston of Sherbrooke, Canada, for referring this patient to us.
M yxoma of the Atritlm: Successful Surgical Treatment
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Fig. 141 (Case 11). Roentgenogram of thorax.
first symptom to the gradual development of abdominal swelling which had its onset 17 months previously. On direct questioning he admitted that he had minimal dyspnea on exertion for the previous 4 years. After its onset the abdominal swelling was associated with anorexia, swelling of the ankles, and eventually a prominent venous pattern over the lower extremities, cyanosis of the fingers and toes, and an increase in nocturnal urinary output with a decrease in the daytime output. Diuretics and paracentesis had been used; he had not been digitalized, but sodium restriction and diuretics had been notably ineffective. He had been hospitalized for 9 months under the presumed diagnosis of constrictive pericarditis. Cardiac catheterization demonstrated a diastollc gradient of pressure between the right atrium and right ventricle of 8 mm. of mercury. It was concluded that tricuspid stenosis existed. The patient was dismissed fronl the hospital, but his symptoms recurred and at operation, 3 months before his admission to the Clinic, palpation within the right atriun1 revealed a huge intracardiac tumor. The operation was confined to exploration and the patient's symptoms persisted. On examination at the Clinic he appeared chronically ill, carried the stigmas of "cardiac cachexia" and maintained an orthopneic position. Marked ascites ,vas present and a prominent venous pattern was noted over the legs and abdomen. The veins in the neck were dilated and tense when he assumed an upright position ,vith consequent obliteration of the jugular pulse waves. The blood pressure was 90 mm. of mercury systolic and 60 mm. diastolic and the arterial pulses were present and equal in all extremities. The diaphragm was high and the lungs were clear to auscultation. The transverse diameter of the heart was increased and a to-and-fro friction rub was heard at the left lower sternal border. A systolic murmur, grade 2, was audible in the pulmonic area and 4 heart sounds were heard at the apex. These were helieved to be the normal first sound, a systolic gallop sound, the second heart sound and a reduplication of the latter. Laboratory studies revealed values for leukocyte count and hemoglobin and results of urinalysis to be normal. The sedimentation rate was 38 mm. in 1 hour (Westergren). The bromsulphalein test showed 16 per cent retention in 1 hour and the value for hilirubin per 100 cc. of serum was 0.33 mg. direct and 0.32 mg. indirect. A thoracic roentgenogram showed cardiomegaly, probably right auricu-
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F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
Fig. 142 (Case 11). Appearance and location of tumor encountered at operation. The right atrium and ventricle are shown widely opened to facilitate orientation of the viewer.
Fig. 143 (Case 11). Gross appearance of right atrial myxoma after removal.
M yxoma of the Atrium: Successful Surgical Treatment
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lar enlargement, and elevation of the right hemidiaphragm (Fig. 141). The electrocardiogram taken soon after admission, with the patient undigitalized, revealed an auricular rate of 200, ventricular rate of 110, auricular fibrillation and an impure auricular flutter with a predominant 2:1 block. He was digitalized and paracentesis productive of 10,850 cc. was carried out. Postoperatively, the tracing exhibited a sinus arrhythmia with apparent occasional sinus arrest, ventricular escape and a changing pacemaker within the sinus node. Two days later operation was performed. The thorax was entered through a bilateral anterior thoracotomy incision. There were many adhesions in the right hemithorax. The left subclavian artery was cannulated, as were the 2 venae cavae, and extracorporeal circulation was instituted. The right atrium was huge and tense; pressures \vithin it varied between 24 to 30 mm. systolic prior to perfusion. After opening the a triuma large intracardiac tumor was visualized, filling practically the entire right atrium and extending into the right ventricle through a dilated tricuspid ring. It was attached by a 2-cm. pedicle to the atrial septum just cephalad to the fossa ovalis (Fig. 142). The tumor was removed completely in pieces. It measured 10 cm. in diameter and weighed 175 grams (Fig. 143). The right atrial wall was closed and extracorporeal circulation was discontinued after 29 minutes. Pressures in the right atrium dropped to bet,veen 10 and 15 mm. of mercury. Tricuspid insufficiency, grade 2, was present, presumably on the basis of the dilated tricuspid ring. The patient's convalescence was rapid and uneventful. The venous pressure remained slightly elevated, measuring 17 cm. of saline prior to dismissal. A slight reaccumulation of ascites was present at the time of his dismissal from the hospital 2 weeks after operation. He was well when last heard from 4~ months after operation.
Pathologic Features* CASES I AND 11. The surface of the tumors was smooth and gently lobular with occasional villous or polypoid projections. The consistency varied from firm and rubbery (Case I) to soft and gelatinous (Case 11). Histologically the tumors were similar (Figs. 140, band 144, a and b). Each had an outer viable shell of tissue composed principally of collagen. Many foci of mucoid material which stained blue with hematoxylin and eosin could be noted. In the center of the mucoid material was a cord of cells resembling a blood vessel (Fig. 144 a). The lumen was exceedingly narrow but some blood cells could be identified within the lumen. In some areas the collagenous material was relatively avascular and showed individual cells that somewhat resembled chondrocytes (Fig. 140, b). Focal hemosiderin containing macrophages was present. In each case the center of the tumor was infarcted. Special stains for connective tissue revealed that the material in the center of the mass contained collagenous fibers alternating with amorphous material that did not take a specific stain for collagen. Focal calcification was present in each case. It was evident grossly in Case II (Fig. 144, b). COMMENT
Although the rarity of primary intracardiac tumors has been emphasized in most reports, there seems little doubt that they will be recognized more frequently as methods of clinical diagnosis improve. Certainly the * We are indebted to Dr. Jesse E. Edwards of the Section of Pathologic Anatomy
for his analysis of the pathologic aspects of these two tumors.
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F. Henry Ellis, Jr., Harold T. Mankin, Hou'ard B. Burchell
Fig. 144 (Case 11). Myxoma. a, Narrovv capillarylike structures surrounded by mucous material. b, Foci of calcification. Stain used: hematoxylin and eosin; reduced from X 120.
growing numbers of reports of myxomas of the atrium encountered at surgical exploration of the heart for presumed mitral stenosis suggest that the lesion may occur more frequently than realized. In a recent review, Kaufman and Cohen collected 500 tumors of the heart of which nearly 50 per cent were myxomas. They occur almost exclusively in the atria and 75 per cent are found in the left atrium. ls Most of them are polypoid and are attached by a small pedicle to the fossa ovalis or its rim, as was true in the two cases reported herein. Pathologic Aspects
The histologic appearance of the two tumors in these cases is similar to that of other myxomas reported in the literature. Raeburn is of the opinion that these tumors arise from elements of pre-existing intramural hamartomas and that they should be termed "hamartoblastomas" or "angiomyxomas." Whatever their origin and whatever term is applied to them, we are of the opinion that they are primary tumors and not thrombi. Not only do these tumors occur in hearts otherwise free of disease but they are located primarily in the atria and rarely, if ever, in the ventricles. They do not occur in the auricular appendage where thrombi develop most frequently but are most often attached by a pedicle to the fossa ovalis or its rim. Clinical Features and Diagnosis
It is evident, from previously reported cases, that myxoma of the atrium more closely simulates the various manifestations of rheumatic heart disease than any other clinical entity. Though cardiac catheteriza-
Myxoma of the Atrium: Successful Surgical Treatment
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tion1, 6 and angiocardiographyl, 7, 8,17 may be significant diagnostic aids, their application rests on the appropriate selection of suitable patients. Our hope of an accurate preoperative or antemortem diagnosis begins with an acute awareness of the natural history of rheumatic heart disease. Thereby our index of suspicion may increase when we encounter deviations from the usual pattern of disease at the mitral and tricuspid valves. When the course of events fails to satisfy the logical criterion usually met by valvular heart disease, then atrial myxoma and its variants may offer a better explanation to the picture. The pathologic physiology encountered is largely dependent on the size of the tumor., its orientation to portals of atrial inflow and outflow, its mobility and length of pedicle, and its potential for embolization or for the formation of thrombotic material on its surface. A high percentage of the atrial volume may be occupied by the tumor. The attainment of a certain critical size would impede forward flow without necessarily obstructing inflow pathways or valvular function, per se. Proximity of the tumor to the pulmonary vein orifices should elevate the pulmonary artery wedge pressure resulting in pulmonary edema and ultimately in elevation of the pulmonary artery pressure and right ventricular hypertrophy. This would be not unlike rheumatic mitral stenosis but with little or no increase in left atrial size, perhaps simulating cor triatriatum or thrombosis of the pulmonary veins. An orientation close to the mitral orifice would impede left atrial outflow with a similar result, yet the size of the left atrium might be more likely to increase, mimicking mitral stenosis, mitral insufficiency or a ball-valve thrombus of the left atrium. Myxomas in the right atrium are equally capable of providing inflow obstruction from the venae cavae or outflow obstruction via the tricuspid orifice. In these cases standard catheterization of the right side of the heart may be highly productive. A diastolic pressure gradient across the tricuspid orifice with no elevation of the pulmonary artery wedge pressure would be quite suggestive of a right atrial myxoma, since rheumatic tricuspid stenosis is almost invariably associated with coexisting mitral stenosis. If no tricuspid gradient is found in the presence of elevated but equal right atrial and right ventricular diastolic pressures, the cause would likely be some restriction to diastolic filling such as constrictive pericarditis or amyloid disease of the myocardium, cirrhosis, or myocarditis. In studying myxoma of the atrium we should remind ourselves of aspects of the clinical picture which are unlike those of rheumatic valvular disease. A history of acute rheumatic fever may be elicited in these cases, but it is rare. The orderly progression through the various phases of progressive disability found in valvular disease may be absent. We find the usual time sequence much compressed or the story punctuated by crises followed by periods of comparatively good health. Previous cardiac auscultation may have been normal, and later a severely dis-
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F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
abled patient may exhibit physical findings that should have been present for many years. Reliable observers may note marked disagreement in their auscultatory conclusions, may report different findings in the same patient on successive days, or may note that the murmurs vary widely with the patient's change in body position. Syncopal attacks are usually seen in patients with aortic valve disease, but if they occur in patients regarded as having mitral valve disease, they should alert one to the possibility of atrial myxoma. Episodic cyanosis usually seen in congenital heart disease with right-to-Ieft shunt, or the blue extremities resulting from a high extraction of oxygen by the tissues in extremely low systemic output states, may occur in patients with myxoma virtually without warning. Breathlessness out of proportion to the objective findings of disease by cardiac fluoroscopy and so forth would be a significant disparity. Wide and sudden swings in the clinical course, as well as a dismaying absence of good response of the patient's congestive failure to the usual cardiac therapy, invite further investigation. The patient may insist on an unusual body position during periods of severe breathlessness, such as being supine and without benefit of pillows. Orthopnea is most often conspicuously absent. In spite of episodes of severely disabling symptoms, the patient may periodically enjoy a remarkably good exercise tolerance by contrast. l-'he condition may simulate bacterial endocarditis but with no organism isolated from the blood stream, or myalgias and arthralgias may be present with little or no elevation in the sedimentation rate and no antecedent pharyngitis. Conflict may arise as to the degree of incapacity and the relative absence of objective data on careful study. The pulmonic second sound may not be appropriately increased or the mitral systolic murmur may not be classically pansystolic. The mitral diastolic murmur may be of unusual quality and pitch or the apical opening snap may be absent. The left atrium and segment of pulmonary artery may be little enlarged and evidences of ventricular hypertrophy may be disappointing. Of special differential importance would be the finding histologically of neoplastic tissue that had embolized to a peripheral artery, allowing a positive diagnosis. When features such as those enumerated are prominent in a case under study, the presence of an atrial myxoma may be seriously considered. The clinical pictures of rheumatic heart disease and of myxoma of the atrium are similar in many respects. In both we find a preponderance of women being afflicted, the ratio being about 3: 1 in myxoma in postmortem material. Myxoma becomes symptomatic in persons 30 to 60 years of age and affects the left side of the heart approximately seven times as frequently as the right side. The murmurs in the mitral region are sometimes nearly identical to those heard in association with rheumatic heart disease, and the clinical pictures of bacterial endocarditis,
Myxoma of the Atrium: Successful Surgical Treatment
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rheumatic activity and embolic events are often similar and seen with frequency. The electrocardiogram may show P waves of increased amplitude and duration, right ventricular strain, right ventricular hypertrophy, paroxysmal auricular tachycardia, auricular flutter, auricular fibrillation, premature ventricular contractions and bundle-branch block in both conditions. Enlargements of various cardiac chambers and variations in the size of the pulmonary artery segment are not pathognomonic for either disease state. The differentiation is not easily made or suspected on the basis of isolated facets of a clinical picture. Rather, it rests on a total appraisal of all available data and the final over-all impression it creates. Especially valuable illustrative examples are to be found in the cases of Paquet and Harvey. SURGICAL CONSIDERATIONS
The urgent necessity for removal of a myxoma of the atrium is evident from the preceding comments on symptomatology. In the two cases reported the patients were in serious difficulty because of their disease and most surely would have died had they not had definitive surgical interference. Although there have been repeated surgical attempts at removal of an intracardiac myxoma, only seven reports of successful complete removal could be found in the literature. The two cases reported herein raise the total to nine (Table). The ages of the patients ranged from 25 to 61 years, with a ratio of women to men of 2: 1. The diagnosis was made preoperatively by angiocardiography in only two cases and anticipated by the clinical data and cardiac catheterization findings in a third. The remaining six patients Were operated on primarily for suspected mitral or tricuspid valvular disease. The tumor was located in the left atrium in all but two patients. Open cardiotomy was facilitated in four cases by hypothermia and inflow stasis, while in five some form of extracorporeal circulation was employed. The necessity for open cardiotomy for correction of these lesions seems obvious. Incomplete removal or the release of emboli would seem inevitable by any closed method. Either hypothermia or extracorporeal circulation can be employed for lesions located in the right atrium. We have a distinct preference, however, for the use of extracorporeal circulation particularly when the left atrium is to be entered. The added time factor afforded by this method is a great advantage. The avoidance of air emboli or tumor emboli is probably facilitated by its use. In five of the seven cases of left atrial tumor, the lesion was approached from the left side directly thfough the left atrium. We agree with Brock that a safer and simpler approach to the left atrium is by way of the right atrial chamber. The atrial septum can easily be opened to expose the left atrium. When the left atrium is large it can usually be opened directly from the right side allowing good exposure.
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F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell Table MYXOMA OF THE ATRIUM: SUCCESSFUL COMPLETE EXCISION
REPORT OF CASES
YEAH.
AGE (YR.) AND SEX OF PATIENT
MYXOMA: LOCATION AND SIZE
Craaford
1955
40-50 F
Bigelow and coauthors Scannell and coauthors Bahnson and coauthors 2 Hanlon
1955
56 F
Lt. atrium; 8 by 4 cm.
1956
33
Lt. atrium; 872 by 372 cm. Lt. atrium; 4 by 5 by 6 cm. Rt. atrium; 'f
M
1957
57 F
1957
61 F
Chin and Ross
1957
25 M
Robertson
1957
38 F
Present paper
1958
45 F
1958
48 M
Lt. atriuln: ?
Lt atrium; 8 by 7 cm.; 60 gm. Lt. atrium; 6 cm. in diameter Lt. atrium; 5 by 4 by 4 cm.; 34 gm. Rt. atrium; 10 cm. in diameter; 175 gm.
ADJUNCTIVE METHOD EMPLOYED
COMMENT
Diagnosed by angiocardiography. Well 1 year later Operated on for miHypothermia tral stenosis. Well 3 months later Operated on for miHypothermia tral stenosis. Well 5 months later Extracorporeal Operated on for micirculation tral stenosis. Well 6 months later Extracorporeal Diagnosed by angiocirculation cardiography. Well 2 weeks later. Operated on for miHypothermia tral stenosis. Survived operation
Extracorporeal circulation
Hypothermia Extracorporeal circulation Extracorporeal circulation
Operated on for mitral stenosis. Well 4 months later Case I
Case 11
"fhe size and location of the tumors in our two patients led to continuing valvular insufficiency in the postoperative period. This we hope to be only temporary, but it must be kept in mind as a possible cause of postoperative morbidity. In Case I the location of the tumor in the posteromedial commissure led to slight persistent mitral insufficiency. l"he huge size of the tumor in Case 11 resulted in marked dilatation of the tricuspid ring with residual tricuspid insufficiency. SUMMARY
Myxomas of the atrium account for 50 per cent of intracardiac tumors and are being recognized more frequently than heretofore. Pathologically they are made up of mucoid material surrounded by an outer shell of collagen. Tumor necrosis and focal calcification are frequently present. It is our opinion that they represent true tumors and not thrombi.
M yxoma of the Atrium: Successful Surgical Treatment
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Clinically these tumors more closely simulate the various manifestations of rheumatic heart disease then any other clinical entity. A correct preoperative or antemortem diagnosis is difficult. The use of cardiac catheterization and angiocardiography, together with a total apprasial of all available data, may alert the clinician to suspect the correct diagnosis. Surgical removal is indicated and can be carried out successfully by means of extracorporeal circulation, as indicated by the two cases we have reported. REFERENCES 1. Bahnson, H. T. and Newman, E. V.: Diagnosis and Surgical Removal of Intracavitary Myxoma of the Right Atrium. Bull. Johns Hopkins Hosp. 93: 150163, 1953. 2. Bahnson, H. T., Spencer, F. C. and Andrus, E. C.: Diagnosis and Treatment of Intracavitary Myxomas of the Heart. Ann. Surge 145: 915-925 (June) 1957. 3. Bigelow, W. G., Dolan, F. G. and Campbell, F. W.: The Effect of Hypothermia upon the Risk of Surgery. Soc. Internat. de Chir., 16th Cong., 1955, pp. 631644. 4. Brock, Russell: The Surgical Approach to the Left Atrium: Removal of an Atrial Myxoma. Guy's Hosp. Rep. 105: 382-390, 1956. 5. Chin, E. F. and Ross, O. N.: Myxoma of the Left Atrium: Successful Surgical Removal Under HypotherIuia. Brit. M. J. 1: 1447-1448 (June 22) 1957. 6. Connolly, D. C. and Wood, E. R.: Hemodynamic Data During Rest and Exercise in Patients with Mitral Valve Disease in Relation to the Differentiation of Stenosis and Insufficiency froIn the Pulmonary Artery Wedge Pressure Pulse. J. Lab. & Clin. Med. 1,.9: 526-544 (Apr.) 1957. 7. Craaford, CIarence: Discussion. In: International Symposium on Cardiovascular Surgery. Studies in Physiology, Diagno3is and Techniques. Philadelphia, W. B. Saunders Company, 1955, pp. 202 and 203. 8. RanIon, C. R.: Discussion. Ann. Surge 145: 925 (June) 1957. 9. Harvey, J. C.: Myxoma of the Left Auricle. Ann. Int. Med. 47: 1067-1081 (Dec.) 1957. 10. Hoffman, J. 1. E. and Rowe, G. G.: Personal communication to the authors. 11. Kaufman, B. H. and Cohen, S. E.: Primary Tumor of the Heart (Reticulum Cell Sarcoma). New York J. Med. 57: 2652-2658 (Aug. 15) 1957. 12. Paquet, E.: The Diagnostic Approach to Auricular Myxomas. Canad. M. A. J. 71,.: 121-124 (Jan. 15) 1956. 13. Prichard, R. W.: Tumors of Heart: Review of Subject and Report of 150 Cuses. A.M.A. Arch. Path. 51: 98-128 (Jan.) 1951. 14. Raeburn, C.: The Histogenesis of Four Cases of Angiomyxoma of the Auricle. J. Clin. Path. 5: 339-344 (Nov.) 1952. 15. Robertson, R.: Primary Cardiac Tumours: Surgical Treatment. Am..J. Surf;!. 91,.: 183-193 (Aug.) 1957. 16. Scannell, J. G., Brewster, W. R. Jr. and Bland, E. F.: Successful Removal of a Myxoma from the Left Atrium. New England J. Med. 254: 601-604 (March 29) 1956. 17. Steinberg, Israel, Dotter,' C. T. and Glenn, Frank: Myxoma of the lIeart: Roentgen Diagnosis During Life in Three Cases. Dis. Chest. 21,.: 509-520 (Nov.) 1953. 18. Wood, E. H. and Wood'Nard, E., Jr.: A Simple Method for Differentiating Mitral Regurgita.tion from Mitral Stenosis by Means of Indicator-Dilution Curves. Proc. Staff. Meet., Mayo Clin. 32: 536-541 (Sept. 18) 1957. 19. Woodward, Edward, Jr., BurcheIl, H. B. and Wood, E. H.: Dilution Curves Associated with Valvular Regurgitation. Proc. Staff Meet., Mayo Clin 32: 518-525 (Sept. 18) 1957.
T~. ]~URCH:EI~L
tumors of the heart are not encountered frequently and are rarely diagnosed before death. Myxoma of the heart comprises about 50 per cent of all primary cardiac tumors and is being recognized more frequently, particularly during left atrial explorations in patients suspected of having mitral stenosis. Efforts to establish the diagnosis clinically should be encouraged for this is a benign curable lesion. Advances in open heart surgery now allow complete removal of an intracavitary myxoma of the atrium with restoration of the hemodynamics. The purpose of this paper is to present our surgical experience with this condition. The cases of two patients who underwent successful surgical excision of atrial myxomas are reported. In one patient (Case I), the tumor was located in the left atrium; in the other (Case 11), it was located in the right atrium. PRIMARY
REPORT OF CASES
Clinical Features CASE T. * A 45-year-old woman was referred to the Clinic with a history of weakness and exhaustion of 7 years' duration. For the previous 14 months, she had had repeated episodes of "dizzy spells" and had been troubled by palpitation and dyspnea on exertion. One year previously she had undergone a minor operation on the scalp elsewhere, followed in 4 days by fever, sore throat, arthralgia, myalgia and diffuse pain in the anterior region of the thorax. A diagnosis of acute rheumatic fever or bacterial endocarditis had been entertained. Seven months before coming to the Clinic her home physician had made a diagnosis of probable rheumatic mitral valvulitis with mitral stenosis. Four months before examination she had had a period of unconsciousness lasting 48 hours with partial right hemiparesis suggesting an embolic event. Subsequently, she"lacked
* Case I is included through the courtesy of Dr. John W. Kirklin. We are indebted to Dr. Morgan Matthews, Shreveport, Louisiana, for referral of this patient. 1087
1088 F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
Fig. 139 (Case I). a, Postero-anterior view of thorax. b, Lateral view.
stamina, experienced subjective palpitation episodically and exhibited moderate postural hypotension. On examination she appeared pale and chronically ill. There was no distention of the veins in the neck and the blood pressure was 90 mm. of mercury systolic and 60 mm. diastolic. A diffuse apical beat was noted from the left nipple to the sternum. The pulmonic second sound was accentuated, grade 2, and the mitral first sound was narrowly split and accentuated, grade 4. A third apical heart sound that did not seem to be an "opening snap" and an apical systolic murmur, grade 2, were heard, but at no time was an apical diastolic murmur audible. The left border of cardiac dullness was in the anterior axillary line. Hepatomegaly or other physical findings of note were absent save for mild residual neurologic deficit of a left cerebral infarct. The laboratory data including determination of hemoglobin, leukocyte count and differential leukocyte counts, value for urea and results of urinalysis, and the Kline test were negative or normal. The sedimentation rate was 51 mm. in 1 hour (Westergren method). The thoracic roentgenogram and cardiac fluoro~copic views (Fig. 139, a, b) revealed moderate cardiac enlargement. Calcification of the mitral valve was not apparent. The electrocardiograms showed low voltage in the standard and unipolar limb leads and inversion of the T wave V-I through V-3. Changes in body position and mild exertion precipitated the appearance of bigeminy related to alternate premature ventricular contractions. A clinical diagnosis of mitral stenosis was entertained, but the natural history of the patient's disease was regarded as highly atypical. The diagnosis of atrial myxoma was given priority in the clinical appraisal. Catheterization of the right side of the heart was undertaken in the hope of resolving the enigma. The findings were a low cardiac index (2.1 liters per minute per square meter), no evidence of an intracardiac shunt and elevated pressures in the right ventricle (61 mm. of mercury systolic and 6 mm. diastolic) , pulmonary artery (61/28) and in the pulmonary artery wedge position (34/15). The "wedge" pressure pulse contour revealed a prominent V wave. The mixed venous saturation (pulmonary) was 66 per cent by Van Slyke analysis.
Myxoma oj' the Atriurn: Success.,ful Surgical 1 reatment 1
1089
The pressures were noted to fluctuate over a considerable range which occurred at the several sites in an irregular but cyclic manner. These undulations of pressure were not synchronous with respirations, alterations in basic cardiac rhythm, or body position. Pressures were observed to fluctuate on occasions, in the pulmonary trunk and right ventricle between 50/21 to 90/30 and 53/4 to 90/0, respectively. The peak of the "V wave" in the wedge contour was likewise noted to range from 25 to 40. These variations were interpreted as further evidence of intermittent and varying degrees of obstruction to left atrial outflow. The very high V wave in the pulmonary artery wedge pressure would place this patient in the group of patients with predominant mitral regurgitation, if interpreted in the light of our experience. 6 Indicator-dilution curves recorded with the use of cuvette oximeter sampling at the radial artery with injections of T-1824 into the pulmonary trunk and superior vena cava were productive of time components essentially normal for these injection sites. The secondary peak in dye concentration in the curves, indicating systemic recirculation of the indicator, were regarded as minimal in amplitude and consistent with a reduced cardiac output. However, an apparent disparity existed between the anticipated degree of mitral insufficiency on inspection of the contour of the pulmonary artery wedge pressure pulse6 and that indicated by study of the after portion of the dye-dilution curves. * 18, 19 It might be reasoned that the dilution curve was nearly normal by virtue of the rapid washout characteristics of a normal-sized left atrium whose volume was reduced by a space-occupying lesion. Whereas, the usual case of mitral disease with an inordinately high "V wave" in the "wedge" contour may be expected to exhibit a greatly distorted disappearance slope of the dye curve owing to the slow washout characteristics of a large-volume left atrium and a markedly regurgitant mitral valve. It also may be conjectured that the atrial tumor was pushed in a retrograde direction to obstruct the pulmonary veins in systole or to act as a piston in the left atrium. A venous angiocardiogram was made, but it failed to show evidence of the tumor. Exploratory cardiotomy without the cardiac bypass was undertaken because, statistically, mitral stenosis seemed more likely than atrial tumor and the angiocardiogram had not allowed visualization of a tumor. Palpation within the left atrium revealed a powerful regurgitant jet of blood from the left ventricle and a smooth, rubbery tumor the size of a golf ball in the left atrium. The incision was closed. Seven days later the patient was reoperated on through an anterior thoracotomy incision. The left subclavian artery and the venae cavae were cannulated and extracorporeal circulation was instituted. The left atrium was approached by opening the right atrium and incising the atrial septum. A tumor, measuring 5 by 4 cm. and weighing 34 grams, was found attached to the atrial septum above the mitral valve (Fig. 140). A tongue of the tumor was wedged into the posteromedial commissure of the mitral valve and was responsible for mitral insufficiency. The tumor was completely removed in several pieces. The atrial septum was closed, as was the wall of the right atrium, and extracorporeal circulation was discontinued after 30 minutes. A grade 2 regurgitant jet of blood could still
* We are indebted to Dr. E. H. Wood for making available the data gathered in the cardiac catheterization laboratory on Case 1. The apparent disparity between the dye-dilution curves and the pulmonary artery wedge pressure pulse contours is being studied in this laboratory. Studies, carried out on a schema simulating the central circulation, indicate that the characteristics of the indicator-dilution curve in mitral insufficiency are greatly influenced by the volume of the left atrial chamber. 1O
1090
F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
Fig. 140 (Case I). a, Appearance of cut surface of left atrial myxoma. b, Microscopic appearance of tumor. Individual cells surrounded by mucous material. Pattern reminiscent of chondrocytes (hematoxylin and eosin; X200).
be felt in the left atrium, probably due to dilatation of the mitral ring. vVhereas pressure in the right pulmonary vein recorded before removal was 68/14, after removal it had dropped to 18/8. The patient made a slo\v but uneventful postoperative recovery and was dismissed from the hospital to her home on the twenty-seventh day. When last heard from, 5 months after operation, her cardiovascular status was excellent but she was troubled by some functional complaints. CASE 11. A 48-year-old draftsman was referred to the Clinic for excision of a tumor within the right atrium. The diagnosis had been made at another institution after exploration for suspected tricuspid stenosis. * The patient dated his
* We are indebted to Drs. Jean de L. Mignault and Edouard S. Gagnon of Montreal, Canada, and to Dr. Thomas J. Quiston of Sherbrooke, Canada, for referring this patient to us.
M yxoma of the Atritlm: Successful Surgical Treatment
1091
Fig. 141 (Case 11). Roentgenogram of thorax.
first symptom to the gradual development of abdominal swelling which had its onset 17 months previously. On direct questioning he admitted that he had minimal dyspnea on exertion for the previous 4 years. After its onset the abdominal swelling was associated with anorexia, swelling of the ankles, and eventually a prominent venous pattern over the lower extremities, cyanosis of the fingers and toes, and an increase in nocturnal urinary output with a decrease in the daytime output. Diuretics and paracentesis had been used; he had not been digitalized, but sodium restriction and diuretics had been notably ineffective. He had been hospitalized for 9 months under the presumed diagnosis of constrictive pericarditis. Cardiac catheterization demonstrated a diastollc gradient of pressure between the right atrium and right ventricle of 8 mm. of mercury. It was concluded that tricuspid stenosis existed. The patient was dismissed fronl the hospital, but his symptoms recurred and at operation, 3 months before his admission to the Clinic, palpation within the right atriun1 revealed a huge intracardiac tumor. The operation was confined to exploration and the patient's symptoms persisted. On examination at the Clinic he appeared chronically ill, carried the stigmas of "cardiac cachexia" and maintained an orthopneic position. Marked ascites ,vas present and a prominent venous pattern was noted over the legs and abdomen. The veins in the neck were dilated and tense when he assumed an upright position ,vith consequent obliteration of the jugular pulse waves. The blood pressure was 90 mm. of mercury systolic and 60 mm. diastolic and the arterial pulses were present and equal in all extremities. The diaphragm was high and the lungs were clear to auscultation. The transverse diameter of the heart was increased and a to-and-fro friction rub was heard at the left lower sternal border. A systolic murmur, grade 2, was audible in the pulmonic area and 4 heart sounds were heard at the apex. These were helieved to be the normal first sound, a systolic gallop sound, the second heart sound and a reduplication of the latter. Laboratory studies revealed values for leukocyte count and hemoglobin and results of urinalysis to be normal. The sedimentation rate was 38 mm. in 1 hour (Westergren). The bromsulphalein test showed 16 per cent retention in 1 hour and the value for hilirubin per 100 cc. of serum was 0.33 mg. direct and 0.32 mg. indirect. A thoracic roentgenogram showed cardiomegaly, probably right auricu-
1092
F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
Fig. 142 (Case 11). Appearance and location of tumor encountered at operation. The right atrium and ventricle are shown widely opened to facilitate orientation of the viewer.
Fig. 143 (Case 11). Gross appearance of right atrial myxoma after removal.
M yxoma of the Atrium: Successful Surgical Treatment
1093
lar enlargement, and elevation of the right hemidiaphragm (Fig. 141). The electrocardiogram taken soon after admission, with the patient undigitalized, revealed an auricular rate of 200, ventricular rate of 110, auricular fibrillation and an impure auricular flutter with a predominant 2:1 block. He was digitalized and paracentesis productive of 10,850 cc. was carried out. Postoperatively, the tracing exhibited a sinus arrhythmia with apparent occasional sinus arrest, ventricular escape and a changing pacemaker within the sinus node. Two days later operation was performed. The thorax was entered through a bilateral anterior thoracotomy incision. There were many adhesions in the right hemithorax. The left subclavian artery was cannulated, as were the 2 venae cavae, and extracorporeal circulation was instituted. The right atrium was huge and tense; pressures \vithin it varied between 24 to 30 mm. systolic prior to perfusion. After opening the a triuma large intracardiac tumor was visualized, filling practically the entire right atrium and extending into the right ventricle through a dilated tricuspid ring. It was attached by a 2-cm. pedicle to the atrial septum just cephalad to the fossa ovalis (Fig. 142). The tumor was removed completely in pieces. It measured 10 cm. in diameter and weighed 175 grams (Fig. 143). The right atrial wall was closed and extracorporeal circulation was discontinued after 29 minutes. Pressures in the right atrium dropped to bet,veen 10 and 15 mm. of mercury. Tricuspid insufficiency, grade 2, was present, presumably on the basis of the dilated tricuspid ring. The patient's convalescence was rapid and uneventful. The venous pressure remained slightly elevated, measuring 17 cm. of saline prior to dismissal. A slight reaccumulation of ascites was present at the time of his dismissal from the hospital 2 weeks after operation. He was well when last heard from 4~ months after operation.
Pathologic Features* CASES I AND 11. The surface of the tumors was smooth and gently lobular with occasional villous or polypoid projections. The consistency varied from firm and rubbery (Case I) to soft and gelatinous (Case 11). Histologically the tumors were similar (Figs. 140, band 144, a and b). Each had an outer viable shell of tissue composed principally of collagen. Many foci of mucoid material which stained blue with hematoxylin and eosin could be noted. In the center of the mucoid material was a cord of cells resembling a blood vessel (Fig. 144 a). The lumen was exceedingly narrow but some blood cells could be identified within the lumen. In some areas the collagenous material was relatively avascular and showed individual cells that somewhat resembled chondrocytes (Fig. 140, b). Focal hemosiderin containing macrophages was present. In each case the center of the tumor was infarcted. Special stains for connective tissue revealed that the material in the center of the mass contained collagenous fibers alternating with amorphous material that did not take a specific stain for collagen. Focal calcification was present in each case. It was evident grossly in Case II (Fig. 144, b). COMMENT
Although the rarity of primary intracardiac tumors has been emphasized in most reports, there seems little doubt that they will be recognized more frequently as methods of clinical diagnosis improve. Certainly the * We are indebted to Dr. Jesse E. Edwards of the Section of Pathologic Anatomy
for his analysis of the pathologic aspects of these two tumors.
1094
F. Henry Ellis, Jr., Harold T. Mankin, Hou'ard B. Burchell
Fig. 144 (Case 11). Myxoma. a, Narrovv capillarylike structures surrounded by mucous material. b, Foci of calcification. Stain used: hematoxylin and eosin; reduced from X 120.
growing numbers of reports of myxomas of the atrium encountered at surgical exploration of the heart for presumed mitral stenosis suggest that the lesion may occur more frequently than realized. In a recent review, Kaufman and Cohen collected 500 tumors of the heart of which nearly 50 per cent were myxomas. They occur almost exclusively in the atria and 75 per cent are found in the left atrium. ls Most of them are polypoid and are attached by a small pedicle to the fossa ovalis or its rim, as was true in the two cases reported herein. Pathologic Aspects
The histologic appearance of the two tumors in these cases is similar to that of other myxomas reported in the literature. Raeburn is of the opinion that these tumors arise from elements of pre-existing intramural hamartomas and that they should be termed "hamartoblastomas" or "angiomyxomas." Whatever their origin and whatever term is applied to them, we are of the opinion that they are primary tumors and not thrombi. Not only do these tumors occur in hearts otherwise free of disease but they are located primarily in the atria and rarely, if ever, in the ventricles. They do not occur in the auricular appendage where thrombi develop most frequently but are most often attached by a pedicle to the fossa ovalis or its rim. Clinical Features and Diagnosis
It is evident, from previously reported cases, that myxoma of the atrium more closely simulates the various manifestations of rheumatic heart disease than any other clinical entity. Though cardiac catheteriza-
Myxoma of the Atrium: Successful Surgical Treatment
1095
tion1, 6 and angiocardiographyl, 7, 8,17 may be significant diagnostic aids, their application rests on the appropriate selection of suitable patients. Our hope of an accurate preoperative or antemortem diagnosis begins with an acute awareness of the natural history of rheumatic heart disease. Thereby our index of suspicion may increase when we encounter deviations from the usual pattern of disease at the mitral and tricuspid valves. When the course of events fails to satisfy the logical criterion usually met by valvular heart disease, then atrial myxoma and its variants may offer a better explanation to the picture. The pathologic physiology encountered is largely dependent on the size of the tumor., its orientation to portals of atrial inflow and outflow, its mobility and length of pedicle, and its potential for embolization or for the formation of thrombotic material on its surface. A high percentage of the atrial volume may be occupied by the tumor. The attainment of a certain critical size would impede forward flow without necessarily obstructing inflow pathways or valvular function, per se. Proximity of the tumor to the pulmonary vein orifices should elevate the pulmonary artery wedge pressure resulting in pulmonary edema and ultimately in elevation of the pulmonary artery pressure and right ventricular hypertrophy. This would be not unlike rheumatic mitral stenosis but with little or no increase in left atrial size, perhaps simulating cor triatriatum or thrombosis of the pulmonary veins. An orientation close to the mitral orifice would impede left atrial outflow with a similar result, yet the size of the left atrium might be more likely to increase, mimicking mitral stenosis, mitral insufficiency or a ball-valve thrombus of the left atrium. Myxomas in the right atrium are equally capable of providing inflow obstruction from the venae cavae or outflow obstruction via the tricuspid orifice. In these cases standard catheterization of the right side of the heart may be highly productive. A diastolic pressure gradient across the tricuspid orifice with no elevation of the pulmonary artery wedge pressure would be quite suggestive of a right atrial myxoma, since rheumatic tricuspid stenosis is almost invariably associated with coexisting mitral stenosis. If no tricuspid gradient is found in the presence of elevated but equal right atrial and right ventricular diastolic pressures, the cause would likely be some restriction to diastolic filling such as constrictive pericarditis or amyloid disease of the myocardium, cirrhosis, or myocarditis. In studying myxoma of the atrium we should remind ourselves of aspects of the clinical picture which are unlike those of rheumatic valvular disease. A history of acute rheumatic fever may be elicited in these cases, but it is rare. The orderly progression through the various phases of progressive disability found in valvular disease may be absent. We find the usual time sequence much compressed or the story punctuated by crises followed by periods of comparatively good health. Previous cardiac auscultation may have been normal, and later a severely dis-
1096
F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell
abled patient may exhibit physical findings that should have been present for many years. Reliable observers may note marked disagreement in their auscultatory conclusions, may report different findings in the same patient on successive days, or may note that the murmurs vary widely with the patient's change in body position. Syncopal attacks are usually seen in patients with aortic valve disease, but if they occur in patients regarded as having mitral valve disease, they should alert one to the possibility of atrial myxoma. Episodic cyanosis usually seen in congenital heart disease with right-to-Ieft shunt, or the blue extremities resulting from a high extraction of oxygen by the tissues in extremely low systemic output states, may occur in patients with myxoma virtually without warning. Breathlessness out of proportion to the objective findings of disease by cardiac fluoroscopy and so forth would be a significant disparity. Wide and sudden swings in the clinical course, as well as a dismaying absence of good response of the patient's congestive failure to the usual cardiac therapy, invite further investigation. The patient may insist on an unusual body position during periods of severe breathlessness, such as being supine and without benefit of pillows. Orthopnea is most often conspicuously absent. In spite of episodes of severely disabling symptoms, the patient may periodically enjoy a remarkably good exercise tolerance by contrast. l-'he condition may simulate bacterial endocarditis but with no organism isolated from the blood stream, or myalgias and arthralgias may be present with little or no elevation in the sedimentation rate and no antecedent pharyngitis. Conflict may arise as to the degree of incapacity and the relative absence of objective data on careful study. The pulmonic second sound may not be appropriately increased or the mitral systolic murmur may not be classically pansystolic. The mitral diastolic murmur may be of unusual quality and pitch or the apical opening snap may be absent. The left atrium and segment of pulmonary artery may be little enlarged and evidences of ventricular hypertrophy may be disappointing. Of special differential importance would be the finding histologically of neoplastic tissue that had embolized to a peripheral artery, allowing a positive diagnosis. When features such as those enumerated are prominent in a case under study, the presence of an atrial myxoma may be seriously considered. The clinical pictures of rheumatic heart disease and of myxoma of the atrium are similar in many respects. In both we find a preponderance of women being afflicted, the ratio being about 3: 1 in myxoma in postmortem material. Myxoma becomes symptomatic in persons 30 to 60 years of age and affects the left side of the heart approximately seven times as frequently as the right side. The murmurs in the mitral region are sometimes nearly identical to those heard in association with rheumatic heart disease, and the clinical pictures of bacterial endocarditis,
Myxoma of the Atrium: Successful Surgical Treatment
1097
rheumatic activity and embolic events are often similar and seen with frequency. The electrocardiogram may show P waves of increased amplitude and duration, right ventricular strain, right ventricular hypertrophy, paroxysmal auricular tachycardia, auricular flutter, auricular fibrillation, premature ventricular contractions and bundle-branch block in both conditions. Enlargements of various cardiac chambers and variations in the size of the pulmonary artery segment are not pathognomonic for either disease state. The differentiation is not easily made or suspected on the basis of isolated facets of a clinical picture. Rather, it rests on a total appraisal of all available data and the final over-all impression it creates. Especially valuable illustrative examples are to be found in the cases of Paquet and Harvey. SURGICAL CONSIDERATIONS
The urgent necessity for removal of a myxoma of the atrium is evident from the preceding comments on symptomatology. In the two cases reported the patients were in serious difficulty because of their disease and most surely would have died had they not had definitive surgical interference. Although there have been repeated surgical attempts at removal of an intracardiac myxoma, only seven reports of successful complete removal could be found in the literature. The two cases reported herein raise the total to nine (Table). The ages of the patients ranged from 25 to 61 years, with a ratio of women to men of 2: 1. The diagnosis was made preoperatively by angiocardiography in only two cases and anticipated by the clinical data and cardiac catheterization findings in a third. The remaining six patients Were operated on primarily for suspected mitral or tricuspid valvular disease. The tumor was located in the left atrium in all but two patients. Open cardiotomy was facilitated in four cases by hypothermia and inflow stasis, while in five some form of extracorporeal circulation was employed. The necessity for open cardiotomy for correction of these lesions seems obvious. Incomplete removal or the release of emboli would seem inevitable by any closed method. Either hypothermia or extracorporeal circulation can be employed for lesions located in the right atrium. We have a distinct preference, however, for the use of extracorporeal circulation particularly when the left atrium is to be entered. The added time factor afforded by this method is a great advantage. The avoidance of air emboli or tumor emboli is probably facilitated by its use. In five of the seven cases of left atrial tumor, the lesion was approached from the left side directly thfough the left atrium. We agree with Brock that a safer and simpler approach to the left atrium is by way of the right atrial chamber. The atrial septum can easily be opened to expose the left atrium. When the left atrium is large it can usually be opened directly from the right side allowing good exposure.
1098
F. Henry Ellis, Jr., Harold T. Mankin, Howard B. Burchell Table MYXOMA OF THE ATRIUM: SUCCESSFUL COMPLETE EXCISION
REPORT OF CASES
YEAH.
AGE (YR.) AND SEX OF PATIENT
MYXOMA: LOCATION AND SIZE
Craaford
1955
40-50 F
Bigelow and coauthors Scannell and coauthors Bahnson and coauthors 2 Hanlon
1955
56 F
Lt. atrium; 8 by 4 cm.
1956
33
Lt. atrium; 872 by 372 cm. Lt. atrium; 4 by 5 by 6 cm. Rt. atrium; 'f
M
1957
57 F
1957
61 F
Chin and Ross
1957
25 M
Robertson
1957
38 F
Present paper
1958
45 F
1958
48 M
Lt. atriuln: ?
Lt atrium; 8 by 7 cm.; 60 gm. Lt. atrium; 6 cm. in diameter Lt. atrium; 5 by 4 by 4 cm.; 34 gm. Rt. atrium; 10 cm. in diameter; 175 gm.
ADJUNCTIVE METHOD EMPLOYED
COMMENT
Diagnosed by angiocardiography. Well 1 year later Operated on for miHypothermia tral stenosis. Well 3 months later Operated on for miHypothermia tral stenosis. Well 5 months later Extracorporeal Operated on for micirculation tral stenosis. Well 6 months later Extracorporeal Diagnosed by angiocirculation cardiography. Well 2 weeks later. Operated on for miHypothermia tral stenosis. Survived operation
Extracorporeal circulation
Hypothermia Extracorporeal circulation Extracorporeal circulation
Operated on for mitral stenosis. Well 4 months later Case I
Case 11
"fhe size and location of the tumors in our two patients led to continuing valvular insufficiency in the postoperative period. This we hope to be only temporary, but it must be kept in mind as a possible cause of postoperative morbidity. In Case I the location of the tumor in the posteromedial commissure led to slight persistent mitral insufficiency. l"he huge size of the tumor in Case 11 resulted in marked dilatation of the tricuspid ring with residual tricuspid insufficiency. SUMMARY
Myxomas of the atrium account for 50 per cent of intracardiac tumors and are being recognized more frequently than heretofore. Pathologically they are made up of mucoid material surrounded by an outer shell of collagen. Tumor necrosis and focal calcification are frequently present. It is our opinion that they represent true tumors and not thrombi.
M yxoma of the Atrium: Successful Surgical Treatment
1099
Clinically these tumors more closely simulate the various manifestations of rheumatic heart disease then any other clinical entity. A correct preoperative or antemortem diagnosis is difficult. The use of cardiac catheterization and angiocardiography, together with a total apprasial of all available data, may alert the clinician to suspect the correct diagnosis. Surgical removal is indicated and can be carried out successfully by means of extracorporeal circulation, as indicated by the two cases we have reported. REFERENCES 1. Bahnson, H. T. and Newman, E. V.: Diagnosis and Surgical Removal of Intracavitary Myxoma of the Right Atrium. Bull. Johns Hopkins Hosp. 93: 150163, 1953. 2. Bahnson, H. T., Spencer, F. C. and Andrus, E. C.: Diagnosis and Treatment of Intracavitary Myxomas of the Heart. Ann. Surge 145: 915-925 (June) 1957. 3. Bigelow, W. G., Dolan, F. G. and Campbell, F. W.: The Effect of Hypothermia upon the Risk of Surgery. Soc. Internat. de Chir., 16th Cong., 1955, pp. 631644. 4. Brock, Russell: The Surgical Approach to the Left Atrium: Removal of an Atrial Myxoma. Guy's Hosp. Rep. 105: 382-390, 1956. 5. Chin, E. F. and Ross, O. N.: Myxoma of the Left Atrium: Successful Surgical Removal Under HypotherIuia. Brit. M. J. 1: 1447-1448 (June 22) 1957. 6. Connolly, D. C. and Wood, E. R.: Hemodynamic Data During Rest and Exercise in Patients with Mitral Valve Disease in Relation to the Differentiation of Stenosis and Insufficiency froIn the Pulmonary Artery Wedge Pressure Pulse. J. Lab. & Clin. Med. 1,.9: 526-544 (Apr.) 1957. 7. Craaford, CIarence: Discussion. In: International Symposium on Cardiovascular Surgery. Studies in Physiology, Diagno3is and Techniques. Philadelphia, W. B. Saunders Company, 1955, pp. 202 and 203. 8. RanIon, C. R.: Discussion. Ann. Surge 145: 925 (June) 1957. 9. Harvey, J. C.: Myxoma of the Left Auricle. Ann. Int. Med. 47: 1067-1081 (Dec.) 1957. 10. Hoffman, J. 1. E. and Rowe, G. G.: Personal communication to the authors. 11. Kaufman, B. H. and Cohen, S. E.: Primary Tumor of the Heart (Reticulum Cell Sarcoma). New York J. Med. 57: 2652-2658 (Aug. 15) 1957. 12. Paquet, E.: The Diagnostic Approach to Auricular Myxomas. Canad. M. A. J. 71,.: 121-124 (Jan. 15) 1956. 13. Prichard, R. W.: Tumors of Heart: Review of Subject and Report of 150 Cuses. A.M.A. Arch. Path. 51: 98-128 (Jan.) 1951. 14. Raeburn, C.: The Histogenesis of Four Cases of Angiomyxoma of the Auricle. J. Clin. Path. 5: 339-344 (Nov.) 1952. 15. Robertson, R.: Primary Cardiac Tumours: Surgical Treatment. Am..J. Surf;!. 91,.: 183-193 (Aug.) 1957. 16. Scannell, J. G., Brewster, W. R. Jr. and Bland, E. F.: Successful Removal of a Myxoma from the Left Atrium. New England J. Med. 254: 601-604 (March 29) 1956. 17. Steinberg, Israel, Dotter,' C. T. and Glenn, Frank: Myxoma of the lIeart: Roentgen Diagnosis During Life in Three Cases. Dis. Chest. 21,.: 509-520 (Nov.) 1953. 18. Wood, E. H. and Wood'Nard, E., Jr.: A Simple Method for Differentiating Mitral Regurgita.tion from Mitral Stenosis by Means of Indicator-Dilution Curves. Proc. Staff. Meet., Mayo Clin. 32: 536-541 (Sept. 18) 1957. 19. Woodward, Edward, Jr., BurcheIl, H. B. and Wood, E. H.: Dilution Curves Associated with Valvular Regurgitation. Proc. Staff Meet., Mayo Clin 32: 518-525 (Sept. 18) 1957.