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The incidence and significance of pulmonic regurgitation after pulmonary valvulotomy
The incidence and significance of putmonic afier
pulmonary
refjur~i~ution
valvulotomy
James L. Talbert, M.D. Andrew G. Morrow, M.D. N. Perryman Collins, M.D. Joseph W. Gilbert, M.D. Bethesda, Md.
A
precordial diastolic murmur, which suggests the presence of pulmonic regurgitation, is frequently audible in patients who have had a pulmonary valvulotomy for the relief of isolated pulmonary valvular stenosis.‘-g When such a murmur is not heard postoperatively, the clinical assumption has usually been that the valve is competent.4 On the other hand, the appearance of most congenitally stenotic pulmonary valves indicates to the surgeon that stenosis usually cannot be corrected effectively without the creation of a greater or lesser degree of valvular incompetence. Within recent years, hemodynamic as well as clinical methods for determining the presence and magnitude of pulmonic regurgitant flow, and for assessing its physiologic significance, have been developed. These techniques were employed in the study of 23 patients who had undergone pulmonary valvulotomy, and conclusions concerning the incidence and significance of postoperative pulmonic regurgitation are presented in the report which follows. Patients
,and methods
The records of all patients at the Kational Heart Institute who have undergone From
the Clinic of Surgery. National Heart Bethesda, Md. Received for publication JuIy 19, 1962.
590
Institute,
pulmonary valvulotomy were reviewed. In 23 of these patients an assessment of the competency of the pulmonic valve was possible postoperatively and they were selected for detailed evaluation. The presence or absence of pulmonic regurgitation was determined by a comparison of preoperative and postoperative clinical examinations and/or the results of indicatordilution studies carried out at the time of postoperative cardiac catheterization.*O-ll The patients ranged in age from 2 to 50 years. Preoperatively, each demonstrated the typical physical, electrocardiographic, and radiologic findings of valvular pulmonic stenosis with intact ventricular septum, and this diagnosis was established in every patient by catheterization of the right side of the heart and selective angiocardiography. The right ventricular systolic pressures ranged from 50 to 187 mm. Hg; the average was 102 mm. Hg. In 5 patients, interatrial communications were also demonstrated at catheterization. No patient had a diastolic murmur. In 22 of the patients, pulmonary valvulotomy was performed under direct vision, utilizing general hypothermia (11 patients) or cardiopulmonary bypass (11 patients). In every open operation each identifiable commissure of United
States
Department
of Health,
Education,
and
Welfare,
Pulmonic
regurgitation
the valve was divided from the central orifice to the annulus, and in 6 patients a portion of one or more valve leaflets was resected as well. In one patient, valvulotonly was accomplished by closed transventricular incision and dilatation. In no instance was a resection of hypertrophic infundibular stenosis deemed necessary.‘* At intervals, ranging from 6 to 42 months after operation, the patients were reevaluated by clinical examinations and repeat catheterizations of the right side of the heart. All had experienced striking symptomatic improvement, and relief of stenosis was confirmed in each patient by a satisfactory reduction in the systolic pressure gradient across the valve. In 12 patients, pulmonic regurgitation was evidenced by the appearance postoperatively of a diastolic murmur along the left sternal border. In the other 11 patients the competency of the valve was tested at catheterization by the indicator-dilution method previously described. I1 A modified doublelumen catheter was positioned with its distal opening in the main pulmonary artery and its proximal one in the midportion of the right ventricle. Dye was injected into the pulmonary artery while blood was simultaneously withdrawn from the right ventricle through a cuvette densitometer. Results
.
A summary of the preoperative and postoperative clinical, radiographic, electrocardiographic, and hemodynamic findings in the 23 patients is presented in Table I. In all 11 patients in whom the indicator-dilution study was performed a significant quantity of dye was immediately detected in the right ventricle after it had been injected into the pulmonary artery, indicating the presence of incompetence of the valve. A typical curve recorded in one of these patients is reproduced in Fig. 1. No attempt was made to assessregurgitant flow quantitatively. In every patient, however, the fraction of dye regurgitated was large and greatly exceeded the small quantity of reflux which is occasionally seen in normal patients, and which has been attributed to the presence of the catheter. Pulmonic diastolic murmurs were also present in 6
after pulmonary
valvulotomy
591
of the patients in whom regurgitation was evident at catheterization. The diastolic murmurs which were audible and recordable in 18 patients were characteristically low pitched, rumbling, mid-diastolic in time, and usually followed the second heart sound by a short interval (Fig. 2). In several patients the combination of systolic and diastolic components resulted in a to-and-fro murmur over the pulmonic area. Of particular interest was the fact that in 5 patients in whom significant pulmonic regurgitation was demonstrated by indicator-dilution testing, no diastolic murmur was audible, even though a portion of the pulmonic valve had been excised in one of them (Table I). Changes in heart size, as evaluated by a comparison of preoperative roentgenograms with those obtained a year or more after operation, were not striking. Seven patients showed an increase in the cardiothoracic ratio, ranging from 1.5 to 9 per cent. Decreases in heart size were observed in 8 patients, but in only 4 of them was the change greater than 2.5 per cent. In the other 8 patients there was no significant postoperative change in the cardiothoracic ratio. The postoperative electrocardiograms, also obtained a year or more after operation, revealed marked regression of right ventricular prominence in 22 of the 23 patients. This was evidenced by a decrease in the height of the R wave in Lead Vi and a shift of the mean electrical asis in the frontal plane toward normal. In 6 patients the electrocardiogram returned to normal. The one patient (P.S.) whose electrocardiogram did not change significantly had a residual left-to-right shunt through a patent foramen ovale. The right ventricular and pulmonary arterial pressures recorded before and after pulmonary valvulotomy are listed in Table I. In 2 patients the catheter could not be passed into the pulmonary artery at the time of the preoperative study. The pulmonary arterial diastolic pressure decreased in 13 patients from 1 to 6 mm. Hg after operation, was unchanged in 2 patients, and increased from 1 to 4 mm. Hg in 6 patients. In 21 patients the average end-diastolic gradient between the right ventricle and the pulmonary artery prior
592
Talbert, Morrow,
Collins, and Gilbert
every patient in whom this assessmentwas made after pulmonary valvulotomy the valve was proved to be incompetent. The results of the present studies indicate, therefore, that any surgical procedure which adequately relieves pulmonic valvular stenosis must also render the valve incompetent. There is both present and past evidence I-IO SOC.-i to indicate that pulmonic regurgitation may exist in the absence of a characteristic Fig. 1. Indicator-dilution curve recorded with right diastolic murmur. Hanson and co-workers5 ventricular sampling after injection into pulmonary have demonstrated this phenomenon in a artery. The fraction of dye which appears immedipostoperative patient by means of selective ately represents that regurgitated (P.R.), whereas the second larger deflection is dye normally repulmonary arteriography. In 5 of our pacirculated. The midpoint of injection is indicated tients in whom regurgitation was conby the arrow. firmed by indicator-dilution methods, no diastolic murmur was present, even th0ug.h to operation was 3.1 mm. Hg. The average in one of them a portion of the pulmomc gradient in these same patients after valvalve had been excised. The explanation vulotomy was only 1.3 mm. Hg. The endfor the absence of a murmur in the presence diastolic pressures in the right ventricle of proved regurgitation is not clear, a1and the pulmonary artery were identical though the small diastolic pressure gradient in 11 patients postoperatively (Fig. 3). In that exists between the right ventricle and another 11 patients the end-diastolic presthe pulmonary artery in these patients is sure in the pulmonary artery exceeded undoubtedly a factor. It has been reported that in the right ventricle by less than that, with time, n postvalvulotoniy tli3 mm. Hg. These adjustments in diastolic astolic murmur may diminish in intensit\ pressure in the pulmonary artery were reor actually disappear.g This phenomenon flected in an increased pulse pressure in may be explained by the gradual approach all but one patient. of the diastolic pressure in the pulmonar! artery to that in the right ventricle, theret)!. Discussion abolishing regurgitant flow except during A number of previous reports have the earliest part of diastole. The important indicated that pulmonic regurgitation ma? fact remains, that the absence of a tlioccur as the result of either an open~?~5~Y~9 astolic murmur does not preclude the or closed’,3-7 valvulotomy, but it has been presence of pulmouic regurgitation. suggested that the incidence is higher after In the present study there is no evidence an open procedure since this approach to indicate that the presence of pulmouic allows wide incision of the commissures regurgitation in postvalvulotomy patients and removal of valvular tissue, if neceshinders their symptomatic improvement. sary.’ .qs demonstrated by 16 of the paIt is realized, holvever, that evaluation of tients in the present series, however, a postoperative s)rlnptoms is difficult and regurgitant valve may result eve11 when that, at best, these are ;L poor indes of no valvular tissue is removed. It should hemodynamic change. The significant hebe emphasized that the 23 patients demod~xamic finding in these patients, scribed were selected from all those operated other than the decrease in or abolition of upon for pulmonic stenosis because the the s\-stolic pressure grndiellt, was a depresence or absence of pulmonic regurgicrease in the end-diastolic gradient across tation could be proved in them. The indithe pulmonic valve and a corresponding cator method for detecting pulmonic regurincrease in the pulmonary arterial pulse gitation requires the passage of a large pressure. The association of these changes double-lumen catheter, a procedure which with pulmonic regurgitation has been subis impractical or impossible in many pastantiated both esperimcntaIly’3 and clillitients, particularI> small children. I11 cally,‘,j but only the presence of identical
Volume Number
65 5
Pulmonic
Fig. 2. Phonocardiogram record was made over first and second heart murmurs.
regurgitation
after pulmonary
valvulotomy
593
of Patient J.S. after pulmonary valvulotomy. The the second left intercostal space. Sr and Sp indicate the sounds, and S.M. and D.M., the systolic and diastolic
PULMONIC
REGURGITATION
J++JN;&&&:l
Fig. 3. Simultaneous records of pulmonary arterial (PA) and right ventricular (RV) pressures obtained postoperatively in Patient G.R. The presence of pulmonic regurgitation is indicated by the identical pressures at the end of diastole.
diastolic pressures offers diagnostic proof of the lesion.11J4,15 In the present series a satisfactory reduction in the pulmonic systolic pressure gradient was achieved in every patient, but the cardiac silhouette and cardiothoracic ratio remained relatively unchanged after valvulotomy. In many patients, observations have been continued for periods of several years, and have failed
to demonstrate regression of the heart size to normal. In contrast to the lack of right ventricular regression shown by x-ray examination was the rather striking electrocardiographic evidence of decreased right ventricular hypertrophy. With one exception, every patient showed a significant shift in the mean electrical axis of the heart and decreased right ventricular prominence indicated by regression of the
*Patients with tElectrocardiogram PA: Pulmonary
T.B. V.D. C.E. J-K.* E.G. E.H. R.G. J.W. F.S.* M.S. R.H. M.C.* P.M. D.A. K.N. R.J. M.G. W.J.* D.A. C.F. S.G. J .S. G.R.
Patient
pressures W
55/j 150/S 85/? 145/s 100/S 72/10 110/o 155112 140/? 90/2 140/12 187/S 50/3 60/S ?0/2 150/10 6512 ?8/2 100/4 54/3 SO/2 82/5 130/S
S/D
R V
__
(
+ +
+ +
0 0 0 0 0
+ +
:
(S/D)
Z+ +++ +++ +++
E ++ ++
++ E
+
-
+Z
I
U/6)
murmur
Grade diastolic
and
o.f
mean.
21/6 22/6 22/10 15/S 46/13 15/5 15/4 1?/8 15/4 25/S 2?/12 23/12 23/6 1?/4 18/6 12/6 30/10 1?/6 21/? 14/? 16/S 15/5 23/6
S/D
Pd
12 14 15 13 25 9 7 10 9 12 19 16 11 9 9 9 15 10 13 10 10 10 12
28/5 24/6 22/S 30/5 46/13 25/5 35/4 36/6 50/3 SO/6 40/12 31/9 30/6 28/3 SO/6 33/6 31/2 45/6 28/6 20/5 30/2 35/3 2?/6
SID
RJ’
valvulotomy pressures Hd
Mea a
Postoperative (mm.
before and after pulmonic
+
+ -
Valve tissue excised
left-to-right shunts through patent foramen wale. normal postoperatively. artery. RV: Right ventricle. Pressures are systolic/diastolic
residual
11 7 11 9 6 11 17
147? 14/6 12/S 12/? 10/4 15/S 25/12
Mean
11 10 15 10 14 17 9 16 15 15 9 9 12 12
PA
Preoperative (mm.
of clinical and hemodynamic findings
16/S 20/S 20/l 1 15/9 20/12 20/11 13/s 23112 25/10 18/14 1 S/8 1215 18/9 15/5
SID
Table I. Summary
+ +
+ + +
+
+ + +
t
Pulmonic regurgitation test
47 53 44 48 47 41 40 42 46 41 38 44 48 45 45 59 41 45 41 49 48 56 51
Preop. 49 50 53 45 47 39 38 43 50 38 36 49 48 45 50 51 45 48 41 49 47 52 50
( Postap.
Cardiothoracic ratio
30 8 26 4 18 5 30 17 10 25 20 35 12 19 11 33 11 5 6 24 25 35 14
1 Yl,,,pTFiic
7 2 3 3t 15 4 13 10 4 16 7 9 1; 7t 2 ot 9 13 14 1t
3
14
R wave in Lead VI (mm.)
Pdmonic
regurgitation
R wave in Lead Vi. In 6 patients the electrocardiogram returned to within normal limits although there was a slight average increase in the cardiothoracic ratios in these same individuals. This apparent discrepancy between the electrocardiographic and roentgenographic findings would suggest that, after adequate valvulotomy, muscular hypertrophy regresses, but that the regurgitation which inevitably occurs causes the chamber to dilate. This sequence has been substantiated in experimental studies of pulmonic regurgitation, and, presumably, dilatation, due to increased diastolic filling of the ventricle, predominates over the stimulus to hypertrophy occasioned by increased stroke work.16-18 A clinical opinion, widely held, is that pulmonic regurgitation is not a serious consequence of pulmonic valvulotomy~! ,2.5.6,9 Data obtained in patients with isolated pulmonic regurgitation, without pulmonary hypertension, also tend to substantiate this impression.i4 Only one reported patientI with isolated congenital valvular incompetence evidenced decompensation. All the others were either asymptomatic or only minimally so. Esperimentally, it has also been shown that severe degrees of pulmonic regurgitation do not preclude survival,16-18 and, although the effective function of the right ventricle is cornpromised acutely,20 the burden imposed is one that an otherwise normal heart can accept. However, it might be expected that the presence of another lesion which affects the right ventricle would alter this favorable outlook. Evidence that tends to corroborate this hypothesis is found in Patient P.S., in whom a residual left-to-right shunt, complicating pulmonic regurgitation, was associated postoperatively with more severe-s-ray and electrocardiographic evidences of right ventricular prominence. In 2 of the other 3 patients with residual left-to-right shunts the size of the heart increased, and evidence of right ventricular prominence was still apparent electrocardiographically, It may be concluded, therefore, that pulmonic regurgitation of greater or lesser severity is an inevitable sequel of an adequate pulmonary valvulotomy. In the absence of complicating lesions, such as
after pulmonary
valvzilotomy
59.5
pulmonary hypertension or a circulatory shunt, however, it appears that the regurgitant flow is well tolerated and will not alter the favorable prognosis now presented to patients who must undergo operation for pulmonary stenosis. Summary
Detailed clinical and hemodynamic studies were made in 23 patients after surgical correction of valvular pulmonic stenosis. In each, pulmonic regurgitation was shown to be present by the appearance of a diastolic murmur postoperatively and/or by the results of indicator-dilution studies made during postoperative cardiac catheterization. The latter method proved that the pulmonic valve was incompetent ‘in every patient in whom it was applied, including those in whom no diastolic murmur was audible. Satisfactory relief of stenosis was achieved in every patient but right ventricular prominence frequently persisted radiographically in spite of electrocardiographic evidence of regression of right ventricular hypertrophy. These findings suggest that the principal response to the incompetent valve is ventricular dilatation. The results of the study indicate that pulmonic regurgitation is an invariable sequel to adequate pulmonary valvulotomy. In the absence of an associated lesion, however, the hemodynamic burden imposed by the regurgitant flow is apparently well tolerated. REFERENCES 1.
2.
3.
4.
5.
6.
Blount, S. G., Jr., McCord, M. C., Mueller, H., and Swan, H.: Isolated valvular pulmonic stenosis. Clinical and physiologic response to open valvuloplasty, Circulation 10:161, 1954. Blount, S. G., Jr., Van Elk, J., Balchum, 0. J., and Swan, H.: Valvular pulmonary stenosis with intact ventricular septum. Clinical and physiologic response to open valvuloplasty, Circulation 15:814, 1957. Campbell, M., and Brock, R.: The results of valvotomy for simple pulmonary stenosis, Brit. Heart J. 17:229, 1955. Campbell, M.: Valvotomy as a curative operation for simple pulmonary stenosis, Brit. Heart J. 21:415, 1959. Hanson, J. S., Ikkos, D., Crafoord, C., and Ovenfors, C.: Results of surgery for congenital pulmonary stenosis. Comparison of the transventricular and transarterial approaches, Circulation 18:588, 1958. Hosier, D. M., Pitts, J. L., and Taussig, H. B.:
596
Talbert, Morrow,
Am
Collins, and Gilbert
Results of valvulolomy for v-alvular pulmonary stenosis with intact ventricular septum, Circulation 14:9, 1956. 7. Lillehei, C. W., Winchell, I’., Adams, I’., Baronofsky, I., Adams, F., and Varco, R. L.: Puhnonary valvular stenosis with intact ventricular septum, Am. J. Med. 20:756, 1956. 8. McGoon. D. C.. and Kirklin. I. W.: Pulmonic stenosis with intact ventricular septum. Treatment utilizing extracorporeal circulation, Circulation 17:180, 1958. 9. Swan, H., Cleveland, H. C., Mueller, H., and Blount, S. G., Jr.: Pulmonic valvular stenosis: Results and technique of open valvuloplasty, J. Thoracic Surg. 28:504, 1954. 10. Bajec, D. B., Birkhead, N. C., Carter, S. A., and Wood, E. H.: Localization and estimation of severity of regurgitant flow at the pulmonary and tricuspid valves, Proc. Staff Meet. Mayo Clin. 33:.569, 1958. 11. Collins, N. P., Braunwald, E., and Morrow, ,A. G.: Detection of pulmonic and tricuspid valvular regurgitation by means of indicator solutions, Circulation 2Oi.561, 1959. 12. Gilbert. I. W.: Unnublished data. 13. Fowler( N. O., Ma’nnix, E. P., and Noble, W.: Some effects of partial pulmonary valvectomy, Circulation Res. 4:8, 1956.
Heart
May,
14.
.I.
1963
Collins, N. I’., Braunwald, E., and Morrow, A. G.: Isolated congenital puhnonic valvulwr regurgitation. Diagnosis by cardiac catheterization and angiocardiography, Am. J. Med. 28:159, 1960. 15. Fish, R. G., Takaro, T., and Crymes, T.: I’rognostic considerations in primary isolated insufficiency of the pulmonic valve, New England J. Med. 261:739, 1959. 16. Fowler, N. O., and Duchesne, E. R.: Effect of experimental pulmonary valvular insufficiency on the circulation, J. Thoracic Surg. 35:643, 1958. 17. Kay, J. H., and Thomas, V.: Experimental production of pulmonary insufficiency, A.M.A. Arch. Surg. 69:646, 1954. 18. Ratcliffe, J. W., Hurt, R. L., Belmonte, B., and Gerbode, F.: The physiologic effects of experimental total pulmonary insufficiency, Surgery 41:43, 1957. 19. Ford, A. B., Hellerstein, H. K., Wood, C., and Kelly, H. B.: Isolated congenital bicuspid pulmonary valve, Am. J. Med. 20:474, 1956. 20. Austen, W. G., Greenfield, L. J., Ebert, P. A., and Morrow, .4. G.: Experimental study of right ventricular function after surgical procedures involving the right ventricle and pulmanic valve, Ann. Surg. 155:606, 1962.
pulmonary
refjur~i~ution
valvulotomy
James L. Talbert, M.D. Andrew G. Morrow, M.D. N. Perryman Collins, M.D. Joseph W. Gilbert, M.D. Bethesda, Md.
A
precordial diastolic murmur, which suggests the presence of pulmonic regurgitation, is frequently audible in patients who have had a pulmonary valvulotomy for the relief of isolated pulmonary valvular stenosis.‘-g When such a murmur is not heard postoperatively, the clinical assumption has usually been that the valve is competent.4 On the other hand, the appearance of most congenitally stenotic pulmonary valves indicates to the surgeon that stenosis usually cannot be corrected effectively without the creation of a greater or lesser degree of valvular incompetence. Within recent years, hemodynamic as well as clinical methods for determining the presence and magnitude of pulmonic regurgitant flow, and for assessing its physiologic significance, have been developed. These techniques were employed in the study of 23 patients who had undergone pulmonary valvulotomy, and conclusions concerning the incidence and significance of postoperative pulmonic regurgitation are presented in the report which follows. Patients
,and methods
The records of all patients at the Kational Heart Institute who have undergone From
the Clinic of Surgery. National Heart Bethesda, Md. Received for publication JuIy 19, 1962.
590
Institute,
pulmonary valvulotomy were reviewed. In 23 of these patients an assessment of the competency of the pulmonic valve was possible postoperatively and they were selected for detailed evaluation. The presence or absence of pulmonic regurgitation was determined by a comparison of preoperative and postoperative clinical examinations and/or the results of indicatordilution studies carried out at the time of postoperative cardiac catheterization.*O-ll The patients ranged in age from 2 to 50 years. Preoperatively, each demonstrated the typical physical, electrocardiographic, and radiologic findings of valvular pulmonic stenosis with intact ventricular septum, and this diagnosis was established in every patient by catheterization of the right side of the heart and selective angiocardiography. The right ventricular systolic pressures ranged from 50 to 187 mm. Hg; the average was 102 mm. Hg. In 5 patients, interatrial communications were also demonstrated at catheterization. No patient had a diastolic murmur. In 22 of the patients, pulmonary valvulotomy was performed under direct vision, utilizing general hypothermia (11 patients) or cardiopulmonary bypass (11 patients). In every open operation each identifiable commissure of United
States
Department
of Health,
Education,
and
Welfare,
Pulmonic
regurgitation
the valve was divided from the central orifice to the annulus, and in 6 patients a portion of one or more valve leaflets was resected as well. In one patient, valvulotonly was accomplished by closed transventricular incision and dilatation. In no instance was a resection of hypertrophic infundibular stenosis deemed necessary.‘* At intervals, ranging from 6 to 42 months after operation, the patients were reevaluated by clinical examinations and repeat catheterizations of the right side of the heart. All had experienced striking symptomatic improvement, and relief of stenosis was confirmed in each patient by a satisfactory reduction in the systolic pressure gradient across the valve. In 12 patients, pulmonic regurgitation was evidenced by the appearance postoperatively of a diastolic murmur along the left sternal border. In the other 11 patients the competency of the valve was tested at catheterization by the indicator-dilution method previously described. I1 A modified doublelumen catheter was positioned with its distal opening in the main pulmonary artery and its proximal one in the midportion of the right ventricle. Dye was injected into the pulmonary artery while blood was simultaneously withdrawn from the right ventricle through a cuvette densitometer. Results
.
A summary of the preoperative and postoperative clinical, radiographic, electrocardiographic, and hemodynamic findings in the 23 patients is presented in Table I. In all 11 patients in whom the indicator-dilution study was performed a significant quantity of dye was immediately detected in the right ventricle after it had been injected into the pulmonary artery, indicating the presence of incompetence of the valve. A typical curve recorded in one of these patients is reproduced in Fig. 1. No attempt was made to assessregurgitant flow quantitatively. In every patient, however, the fraction of dye regurgitated was large and greatly exceeded the small quantity of reflux which is occasionally seen in normal patients, and which has been attributed to the presence of the catheter. Pulmonic diastolic murmurs were also present in 6
after pulmonary
valvulotomy
591
of the patients in whom regurgitation was evident at catheterization. The diastolic murmurs which were audible and recordable in 18 patients were characteristically low pitched, rumbling, mid-diastolic in time, and usually followed the second heart sound by a short interval (Fig. 2). In several patients the combination of systolic and diastolic components resulted in a to-and-fro murmur over the pulmonic area. Of particular interest was the fact that in 5 patients in whom significant pulmonic regurgitation was demonstrated by indicator-dilution testing, no diastolic murmur was audible, even though a portion of the pulmonic valve had been excised in one of them (Table I). Changes in heart size, as evaluated by a comparison of preoperative roentgenograms with those obtained a year or more after operation, were not striking. Seven patients showed an increase in the cardiothoracic ratio, ranging from 1.5 to 9 per cent. Decreases in heart size were observed in 8 patients, but in only 4 of them was the change greater than 2.5 per cent. In the other 8 patients there was no significant postoperative change in the cardiothoracic ratio. The postoperative electrocardiograms, also obtained a year or more after operation, revealed marked regression of right ventricular prominence in 22 of the 23 patients. This was evidenced by a decrease in the height of the R wave in Lead Vi and a shift of the mean electrical asis in the frontal plane toward normal. In 6 patients the electrocardiogram returned to normal. The one patient (P.S.) whose electrocardiogram did not change significantly had a residual left-to-right shunt through a patent foramen ovale. The right ventricular and pulmonary arterial pressures recorded before and after pulmonary valvulotomy are listed in Table I. In 2 patients the catheter could not be passed into the pulmonary artery at the time of the preoperative study. The pulmonary arterial diastolic pressure decreased in 13 patients from 1 to 6 mm. Hg after operation, was unchanged in 2 patients, and increased from 1 to 4 mm. Hg in 6 patients. In 21 patients the average end-diastolic gradient between the right ventricle and the pulmonary artery prior
592
Talbert, Morrow,
Collins, and Gilbert
every patient in whom this assessmentwas made after pulmonary valvulotomy the valve was proved to be incompetent. The results of the present studies indicate, therefore, that any surgical procedure which adequately relieves pulmonic valvular stenosis must also render the valve incompetent. There is both present and past evidence I-IO SOC.-i to indicate that pulmonic regurgitation may exist in the absence of a characteristic Fig. 1. Indicator-dilution curve recorded with right diastolic murmur. Hanson and co-workers5 ventricular sampling after injection into pulmonary have demonstrated this phenomenon in a artery. The fraction of dye which appears immedipostoperative patient by means of selective ately represents that regurgitated (P.R.), whereas the second larger deflection is dye normally repulmonary arteriography. In 5 of our pacirculated. The midpoint of injection is indicated tients in whom regurgitation was conby the arrow. firmed by indicator-dilution methods, no diastolic murmur was present, even th0ug.h to operation was 3.1 mm. Hg. The average in one of them a portion of the pulmomc gradient in these same patients after valvalve had been excised. The explanation vulotomy was only 1.3 mm. Hg. The endfor the absence of a murmur in the presence diastolic pressures in the right ventricle of proved regurgitation is not clear, a1and the pulmonary artery were identical though the small diastolic pressure gradient in 11 patients postoperatively (Fig. 3). In that exists between the right ventricle and another 11 patients the end-diastolic presthe pulmonary artery in these patients is sure in the pulmonary artery exceeded undoubtedly a factor. It has been reported that in the right ventricle by less than that, with time, n postvalvulotoniy tli3 mm. Hg. These adjustments in diastolic astolic murmur may diminish in intensit\ pressure in the pulmonary artery were reor actually disappear.g This phenomenon flected in an increased pulse pressure in may be explained by the gradual approach all but one patient. of the diastolic pressure in the pulmonar! artery to that in the right ventricle, theret)!. Discussion abolishing regurgitant flow except during A number of previous reports have the earliest part of diastole. The important indicated that pulmonic regurgitation ma? fact remains, that the absence of a tlioccur as the result of either an open~?~5~Y~9 astolic murmur does not preclude the or closed’,3-7 valvulotomy, but it has been presence of pulmouic regurgitation. suggested that the incidence is higher after In the present study there is no evidence an open procedure since this approach to indicate that the presence of pulmouic allows wide incision of the commissures regurgitation in postvalvulotomy patients and removal of valvular tissue, if neceshinders their symptomatic improvement. sary.’ .qs demonstrated by 16 of the paIt is realized, holvever, that evaluation of tients in the present series, however, a postoperative s)rlnptoms is difficult and regurgitant valve may result eve11 when that, at best, these are ;L poor indes of no valvular tissue is removed. It should hemodynamic change. The significant hebe emphasized that the 23 patients demod~xamic finding in these patients, scribed were selected from all those operated other than the decrease in or abolition of upon for pulmonic stenosis because the the s\-stolic pressure grndiellt, was a depresence or absence of pulmonic regurgicrease in the end-diastolic gradient across tation could be proved in them. The indithe pulmonic valve and a corresponding cator method for detecting pulmonic regurincrease in the pulmonary arterial pulse gitation requires the passage of a large pressure. The association of these changes double-lumen catheter, a procedure which with pulmonic regurgitation has been subis impractical or impossible in many pastantiated both esperimcntaIly’3 and clillitients, particularI> small children. I11 cally,‘,j but only the presence of identical
Volume Number
65 5
Pulmonic
Fig. 2. Phonocardiogram record was made over first and second heart murmurs.
regurgitation
after pulmonary
valvulotomy
593
of Patient J.S. after pulmonary valvulotomy. The the second left intercostal space. Sr and Sp indicate the sounds, and S.M. and D.M., the systolic and diastolic
PULMONIC
REGURGITATION
J++JN;&&&:l
Fig. 3. Simultaneous records of pulmonary arterial (PA) and right ventricular (RV) pressures obtained postoperatively in Patient G.R. The presence of pulmonic regurgitation is indicated by the identical pressures at the end of diastole.
diastolic pressures offers diagnostic proof of the lesion.11J4,15 In the present series a satisfactory reduction in the pulmonic systolic pressure gradient was achieved in every patient, but the cardiac silhouette and cardiothoracic ratio remained relatively unchanged after valvulotomy. In many patients, observations have been continued for periods of several years, and have failed
to demonstrate regression of the heart size to normal. In contrast to the lack of right ventricular regression shown by x-ray examination was the rather striking electrocardiographic evidence of decreased right ventricular hypertrophy. With one exception, every patient showed a significant shift in the mean electrical axis of the heart and decreased right ventricular prominence indicated by regression of the
*Patients with tElectrocardiogram PA: Pulmonary
T.B. V.D. C.E. J-K.* E.G. E.H. R.G. J.W. F.S.* M.S. R.H. M.C.* P.M. D.A. K.N. R.J. M.G. W.J.* D.A. C.F. S.G. J .S. G.R.
Patient
pressures W
55/j 150/S 85/? 145/s 100/S 72/10 110/o 155112 140/? 90/2 140/12 187/S 50/3 60/S ?0/2 150/10 6512 ?8/2 100/4 54/3 SO/2 82/5 130/S
S/D
R V
__
(
+ +
+ +
0 0 0 0 0
+ +
:
(S/D)
Z+ +++ +++ +++
E ++ ++
++ E
+
-
+Z
I
U/6)
murmur
Grade diastolic
and
o.f
mean.
21/6 22/6 22/10 15/S 46/13 15/5 15/4 1?/8 15/4 25/S 2?/12 23/12 23/6 1?/4 18/6 12/6 30/10 1?/6 21/? 14/? 16/S 15/5 23/6
S/D
Pd
12 14 15 13 25 9 7 10 9 12 19 16 11 9 9 9 15 10 13 10 10 10 12
28/5 24/6 22/S 30/5 46/13 25/5 35/4 36/6 50/3 SO/6 40/12 31/9 30/6 28/3 SO/6 33/6 31/2 45/6 28/6 20/5 30/2 35/3 2?/6
SID
RJ’
valvulotomy pressures Hd
Mea a
Postoperative (mm.
before and after pulmonic
+
+ -
Valve tissue excised
left-to-right shunts through patent foramen wale. normal postoperatively. artery. RV: Right ventricle. Pressures are systolic/diastolic
residual
11 7 11 9 6 11 17
147? 14/6 12/S 12/? 10/4 15/S 25/12
Mean
11 10 15 10 14 17 9 16 15 15 9 9 12 12
PA
Preoperative (mm.
of clinical and hemodynamic findings
16/S 20/S 20/l 1 15/9 20/12 20/11 13/s 23112 25/10 18/14 1 S/8 1215 18/9 15/5
SID
Table I. Summary
+ +
+ + +
+
+ + +
t
Pulmonic regurgitation test
47 53 44 48 47 41 40 42 46 41 38 44 48 45 45 59 41 45 41 49 48 56 51
Preop. 49 50 53 45 47 39 38 43 50 38 36 49 48 45 50 51 45 48 41 49 47 52 50
( Postap.
Cardiothoracic ratio
30 8 26 4 18 5 30 17 10 25 20 35 12 19 11 33 11 5 6 24 25 35 14
1 Yl,,,pTFiic
7 2 3 3t 15 4 13 10 4 16 7 9 1; 7t 2 ot 9 13 14 1t
3
14
R wave in Lead VI (mm.)
Pdmonic
regurgitation
R wave in Lead Vi. In 6 patients the electrocardiogram returned to within normal limits although there was a slight average increase in the cardiothoracic ratios in these same individuals. This apparent discrepancy between the electrocardiographic and roentgenographic findings would suggest that, after adequate valvulotomy, muscular hypertrophy regresses, but that the regurgitation which inevitably occurs causes the chamber to dilate. This sequence has been substantiated in experimental studies of pulmonic regurgitation, and, presumably, dilatation, due to increased diastolic filling of the ventricle, predominates over the stimulus to hypertrophy occasioned by increased stroke work.16-18 A clinical opinion, widely held, is that pulmonic regurgitation is not a serious consequence of pulmonic valvulotomy~! ,2.5.6,9 Data obtained in patients with isolated pulmonic regurgitation, without pulmonary hypertension, also tend to substantiate this impression.i4 Only one reported patientI with isolated congenital valvular incompetence evidenced decompensation. All the others were either asymptomatic or only minimally so. Esperimentally, it has also been shown that severe degrees of pulmonic regurgitation do not preclude survival,16-18 and, although the effective function of the right ventricle is cornpromised acutely,20 the burden imposed is one that an otherwise normal heart can accept. However, it might be expected that the presence of another lesion which affects the right ventricle would alter this favorable outlook. Evidence that tends to corroborate this hypothesis is found in Patient P.S., in whom a residual left-to-right shunt, complicating pulmonic regurgitation, was associated postoperatively with more severe-s-ray and electrocardiographic evidences of right ventricular prominence. In 2 of the other 3 patients with residual left-to-right shunts the size of the heart increased, and evidence of right ventricular prominence was still apparent electrocardiographically, It may be concluded, therefore, that pulmonic regurgitation of greater or lesser severity is an inevitable sequel of an adequate pulmonary valvulotomy. In the absence of complicating lesions, such as
after pulmonary
valvzilotomy
59.5
pulmonary hypertension or a circulatory shunt, however, it appears that the regurgitant flow is well tolerated and will not alter the favorable prognosis now presented to patients who must undergo operation for pulmonary stenosis. Summary
Detailed clinical and hemodynamic studies were made in 23 patients after surgical correction of valvular pulmonic stenosis. In each, pulmonic regurgitation was shown to be present by the appearance of a diastolic murmur postoperatively and/or by the results of indicator-dilution studies made during postoperative cardiac catheterization. The latter method proved that the pulmonic valve was incompetent ‘in every patient in whom it was applied, including those in whom no diastolic murmur was audible. Satisfactory relief of stenosis was achieved in every patient but right ventricular prominence frequently persisted radiographically in spite of electrocardiographic evidence of regression of right ventricular hypertrophy. These findings suggest that the principal response to the incompetent valve is ventricular dilatation. The results of the study indicate that pulmonic regurgitation is an invariable sequel to adequate pulmonary valvulotomy. In the absence of an associated lesion, however, the hemodynamic burden imposed by the regurgitant flow is apparently well tolerated. REFERENCES 1.
2.
3.
4.
5.
6.
Blount, S. G., Jr., McCord, M. C., Mueller, H., and Swan, H.: Isolated valvular pulmonic stenosis. Clinical and physiologic response to open valvuloplasty, Circulation 10:161, 1954. Blount, S. G., Jr., Van Elk, J., Balchum, 0. J., and Swan, H.: Valvular pulmonary stenosis with intact ventricular septum. Clinical and physiologic response to open valvuloplasty, Circulation 15:814, 1957. Campbell, M., and Brock, R.: The results of valvotomy for simple pulmonary stenosis, Brit. Heart J. 17:229, 1955. Campbell, M.: Valvotomy as a curative operation for simple pulmonary stenosis, Brit. Heart J. 21:415, 1959. Hanson, J. S., Ikkos, D., Crafoord, C., and Ovenfors, C.: Results of surgery for congenital pulmonary stenosis. Comparison of the transventricular and transarterial approaches, Circulation 18:588, 1958. Hosier, D. M., Pitts, J. L., and Taussig, H. B.:
596
Talbert, Morrow,
Am
Collins, and Gilbert
Results of valvulolomy for v-alvular pulmonary stenosis with intact ventricular septum, Circulation 14:9, 1956. 7. Lillehei, C. W., Winchell, I’., Adams, I’., Baronofsky, I., Adams, F., and Varco, R. L.: Puhnonary valvular stenosis with intact ventricular septum, Am. J. Med. 20:756, 1956. 8. McGoon. D. C.. and Kirklin. I. W.: Pulmonic stenosis with intact ventricular septum. Treatment utilizing extracorporeal circulation, Circulation 17:180, 1958. 9. Swan, H., Cleveland, H. C., Mueller, H., and Blount, S. G., Jr.: Pulmonic valvular stenosis: Results and technique of open valvuloplasty, J. Thoracic Surg. 28:504, 1954. 10. Bajec, D. B., Birkhead, N. C., Carter, S. A., and Wood, E. H.: Localization and estimation of severity of regurgitant flow at the pulmonary and tricuspid valves, Proc. Staff Meet. Mayo Clin. 33:.569, 1958. 11. Collins, N. P., Braunwald, E., and Morrow, ,A. G.: Detection of pulmonic and tricuspid valvular regurgitation by means of indicator solutions, Circulation 2Oi.561, 1959. 12. Gilbert. I. W.: Unnublished data. 13. Fowler( N. O., Ma’nnix, E. P., and Noble, W.: Some effects of partial pulmonary valvectomy, Circulation Res. 4:8, 1956.
Heart
May,
14.
.I.
1963
Collins, N. I’., Braunwald, E., and Morrow, A. G.: Isolated congenital puhnonic valvulwr regurgitation. Diagnosis by cardiac catheterization and angiocardiography, Am. J. Med. 28:159, 1960. 15. Fish, R. G., Takaro, T., and Crymes, T.: I’rognostic considerations in primary isolated insufficiency of the pulmonic valve, New England J. Med. 261:739, 1959. 16. Fowler, N. O., and Duchesne, E. R.: Effect of experimental pulmonary valvular insufficiency on the circulation, J. Thoracic Surg. 35:643, 1958. 17. Kay, J. H., and Thomas, V.: Experimental production of pulmonary insufficiency, A.M.A. Arch. Surg. 69:646, 1954. 18. Ratcliffe, J. W., Hurt, R. L., Belmonte, B., and Gerbode, F.: The physiologic effects of experimental total pulmonary insufficiency, Surgery 41:43, 1957. 19. Ford, A. B., Hellerstein, H. K., Wood, C., and Kelly, H. B.: Isolated congenital bicuspid pulmonary valve, Am. J. Med. 20:474, 1956. 20. Austen, W. G., Greenfield, L. J., Ebert, P. A., and Morrow, .4. G.: Experimental study of right ventricular function after surgical procedures involving the right ventricle and pulmanic valve, Ann. Surg. 155:606, 1962.