THoRAc CARDIOVASC SURG
Improved right ventricular function following late pulmonary valve replacement for residual pulmonary insufficiency or stenosis Residual severe pulmonary imufficiency or stenosis may result in significant myocardial dysfunction late after repair of tetralogy of FaUot. Although pulmonary valvereplacement bas been advocated for selected patients, objective improvement in right ventricular function bas been difficult to demonstrate. We undertook pulmonary valve replacement in 11 patients to treat residual imufficiency (n = 8) or stenosis (n = 3) and evaluated them before and after operation by radionuclide ventriculography and M-mode echocardiography. Patients' age at the original repair was 6.6 ± 0.6 years (range 2 to 8 years) and at subsequent valvereplacement was 14.6 ± 1.5 years (range 5 to 20 years), Indications for pulmonary valve replacement were conduit stenosis indicated by a gradient ~75 mm Hg (n = 3), symptoms (n = 2), progressive cardiomegaly (n = 3), and new onset of tricuspid imufficiency (n = 3). Prior to pulmonary valve replacement, right ventricular ejection fraction was 0.29 ± 0.12 (range 0.12 to 0.48) and rose to 0.35 ± 0.10 (range 0.19 to 0.48) at a mean of 10.5 ± 2.3 mon~ after operation (p < 0.05). Improvement (defmed as an increase in ejection fraction >0.05) was noted in seven patients whereas four demonstrated no change. Left ventricular ejection fraction before operation (0.55 ± 0.12) was unchanged after pulmonary valve replacement (0.54 ± 0.06). M-mode echocardiography demonstrated significant reduction in right ventricular dilatation. Right ventricular Ileft ventricular end-diastolic dimension feU from 1.03 ± 0.30 to 0.73 ± 0.13 after operation (p < 0.01). Cardiothoracic ratio feU from 0.59 ± 0.02 to 0.55 ± 0.02 at a mean of 12 months after pulmonary valve replacement (p < 0.01). Subjective improvement in exercise tolerance was noted in aU seven patients who showed an increase in right ventricular ejection fraction. Of the remaining four patients, two had no improvement, one felt symptomaticaUy improved, and one was too young for evaluation. These data demonstrate objective improvement in right ventricular function foUowing pulmonary valve replacement and confrrm the usefulness of this procedure in patients with significant right ventricular dysfunction secondary to residual pulmonary imufficiency and stenosis.
Edward L. Bove, M.D., Rae-Ellen W. Kavey, M.D., Craig J. Byrum, M.D., Henry M. Sondheimer, M.D., Marie S. Blackman, M.D., and F. Deaver Thomas, M.D.,
Syracuse. N. Y.
Late results following complete repair of tetralogy of Fallot have continued to be excellent in the majority of cases. A small group of patients, however, will require a subsequent procedure for a significant residual hemodynamic abnormality. In particular, long-standing severe From the Divisions of Cardiac Surgery, Pediatric Cardiology, and Nuclear Medicine, State University of New York, Upstate Medical Center, Syracuse, N. Y. Received for publication July 19, 1984. Accepted for publication Sept. 14, 1984. Address for reprints: Dr. Edward L. Bove, Department of Surgery, SUNY Upstate Medical Center, 750 E. Adams St., Syracuse, N. y. 13210.
pulmonary insufficiency or stenosis may result in important myocardial dysfunction and symptoms. Increasingly, pulmonary valve replacement has been advocated for selected patients, and a number of reports have shown improvement in symptoms after this procedure. I.. Objective improvement in right ventricular function has been difficult to demonstrate, however.' Previous reports from this institution have shown that long-standing severe pulmonary insufficiency may result in impaired right ventricular function, despite otherwise satisfactory hemodynamic repairs and the absence of symptoms.' The important question of the reversible nature of this dysfunction remains to be answered.
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Table I. Clinical data Patient No.
1 2 3 4 5
Diagnosis and previous procedures
TOF, YSD, TOF TOF, TOF, TOF, TOF TOF,
BTS PAB Waterston BTS absent PY absent PY
Initial management of RVOT RY-PA homograft Transannular patch RY-PA Hancock Pulmonary valvotomy Transannular patch Transannular patch Transannular patch R Y- PA homograft Pulmonary valvotomy RY-PA nonvalved conduit Transannular patch Transannular patch
Age at initial repair (yr)
Age at PVR (yr)
8 8 8
10 8 9
12 19 20
Type and size of pulmonary prosthesis
11 12 1 12
Hancock conduit 25 mm ISPY 27 mm Hancock conduit 25 mm Carpentier-Edwards 25 mm ISPY 25 mm Carpentier-Edwards 25 mm Carpentier-Edwards 23 mm Carpentier- Edwards conduit 25 mm ISPY 21 mm
Carpentier-Edwards 25 mm Carpentier-Edwards 27 mm
8 8 4
Legend: RVOT, Right ventricular outflow Iract. PVR, Pulmonary valve replacement. TOF, Tetralogy of Fallot. BTS, Blalock-Taussig shunt. VSD, Ventricular septal defect. PAB, Pulmonary artery band. PV, Pulmonary valve. RV-PA, Right ventricle to pulmonary artery. ISPV, lonescu-Shiley pericardial valve.
This report focuses on a group of 11 patients who underwent pulmonary valve replacement at the State University of New York-Upstate Medical Center. Right and left ventricular function before and after operation was examined with the technique of radionuelide ventriculography. The relative dimensions of the right and left ventricles were measured by M-mode echocardiography before and after pulmonary valve replacement. In addition, postoperative changes in exercise tolerance, heart size, and dysrhythmias were evaluated. Patients and methods
Between July, 1980, and April, 1983, 11 patients ranging in age from 5 to 20 years (mean 14.6 ± 1.5 years) underwent pulmonary valve replacement for severe residual pulmonary insufficiency or stenosis and were available for complete postoperative evaluation. The diagnosis was tetralogy of Fallot in 10 of these patients; one patient had an isolated ventricular septal defect (Table I). Two of the patients with tetralogy of Fallot had the absent pulmonary valve syndrome and one had the origin of the right pulmonary artery from theascending aorta (hemitruncus). Palliative procedures were done in four patients. Two patients had BlalockTaussig shunts and one had a Waterston anastomosis. The patient with the isolated ventricular septal defect underwent pulmonary artery banding in infancy. The mean age of patients at complete repair was 6,6 ± 0.6 years (range 2 to 8 years). Right ventricular outflow tract obstruction was repaired with a transannular patch in five of the patients with tetralogy of Fallot and in the patient with a ventricular septal defect and
pulmonary artery band (because of the extreme proximal location of the band). A right ventricle-to-pulmonary artery valved conduit was inserted primarily in three patients (two homografts and one Hancock valve). The patient with the origin of the right pulmonary artery from the ascending aorta had placement of a nonvalved right ventricle-to-right pulmonary artery conduit in addition to a pulmonary valvotomy. The final patient had a pulmonary valvotomy alone. The most recent cardiac catheterization before pulmonary valve replacement was performed from 2 to 12 years after the initial repair (mean 7.7 years). Ten patients had undergone more than one catheterization following repair. Cardiothoracic ratios were calculated from standard posteroanterior chest roentgenograms. M-mode echocardiography was done in each patient before and after pulmonary valve replacement, and the right and left ventricular end-diastolic dimensions were expressed as a ratio. Echocardiograms were standardized in relation to the mitral valve leaflets to exclude dilatation of the right ventricular outflow tract in the calculation. Holter monitoring for a 24 hour period was available preoperatively in 10 patients, and the results were graded according to the Lown criteria for ventricular dysrhythmias.? Radionuclide ventriculography with the use of 99mTc pertechnetate-Iabeled red blood cells was performed before and after operation according to techniques previously reported," Right and left ventricular ejection fractions were calculated for each patient. Indications for operation and surgical technique. The indication for pulmonary valve replacement in the three patients with right ventricle-to-pulmonary artery conduits was the recurrence of obstruction, indicated by
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Fig. 1. Cardiothoracic ratios.
a gradient of at least 75 nun Hg. The primary indication in the eight patients with pulmonary insufficiency was progressive exercise intolerance in two patients, progressive cardiomegaly in three patients, and new onset of tricuspid insufficiency with increasing right ventricular dilatation in three patients. Most patients had more than one indication for operation. Standard cardiopulmonary bypass with bicaval cannulation and moderate systemic hypothermia between 28 0 and 32 0 C was used during the operative procedures. Crystalloid cardioplegia was used in each case. Obstructed conduits in three patients were replaced with 25 nun valved conduits (two Hancock and one Carpentier-Edwards). In the remaining eight patients the right ventricular outflow tract was reincised and a prosthetic tissue valve (CarpentierEdwards or Ionescu-Shiley) was inserted into the outflow tract with running polypropylene suture material. The anterior aspect of the outflow tract was then repaired with a Dacron patch similar to the technique described by Laks and associates.' Valve sizes ranged from 21 to 27 nun. A-pulmonary artery angioplasty was performed in the patient with an occluded left pulmonary artery; a tricuspid annuloplasty was done in one patient with particularly severe tricuspid regurgitation. Statistical analysis. Statistical significance was determined at the 95% confidence level by the two-tailed t test for the difference between two means. Paired t tests were used when appropriate. Results are expressed as mean ± standard error. Results Cardiac catheterization. All three patients with valved conduits had severe conduit obstruction with right ventricle-to-pulmonary artery pressure gradients of 75, 81, and 90 nun Hg. Two of these patients had no pulmonary insufficiency but mild tricuspid regurgitation
had developed. The other patient experienced moderate pulmonary insufficiency without tricuspid regurgitation. The remaining eight patients had severe pulmonary insufficiency without significant residual outflow tract obstruction. No patient in this group had a residual right ventricle-to-pulmonary artery pressure gradient greater than 25 nun Hg. Pulmonary artery pressure ranged from 12 to 80 nun Hg (systolic) (mean 32.8 ± 6.2 nun Hg). Moderate to severe tricuspid regurgitation was present in three of these patients. One patient had an occluded right ventricle-to-right pulmonary artery conduit and one had an occluded left pulmonary artery just distal to a transannular patch. These last two patients were the only ones with elevated pulmonary artery systolic pressures (60 and 80 nun Hg). Chest roentgenograms. The cardiothoracic ratio was 0.59 ± 0.02 just prior to pulmonary valve insertion (range 0.47 to 0.72). This value fell to 0.55 ± 0.02 (range 0.48 to 0.68) at a mean of 12 months after operation (p < 0.01) (Figs. 1 and 2). M-mode echocardiography. Significant reduction in right ventricular dilatation was seen by M-mode echocardiography (Fig. 3). Prior to pulmonary replacement the right ventricular/left ventricular end-diastolic dimension was 1.03 ± 0.30 (range 0.60 to 1.49). This ratio fell to 0.73 ± 0.13 (range 0.58 to 0.91) at a mean of 10 months after operation (p < 0.01). Radionuclide ventriculography. Radionuclide ventriculography was performed in all patients within 6 months prior to pulmonary valve replacement and repeated at a mean of 10.5 ± 2.3 months after operation. Right ventricular ejection fraction ranged from 0.16 to 0.48 (mean 0.29 ± 0.12) before operation. After operation this value rose significantly to 0.35 ± 0.10, range 0.19 to 0.48, (p < 0.05) (Fig. 4). Improvement (defined as an increase in ejection fraction >0.05) was noted in seven patients, whereas four demonstrated no change. Among the three patients with conduit stenosis, two improved and one patient did not. For the remaining eight patients with isolated pulmonary insufficiency, five improved and three remained unchanged. Left ventricular ejection fraction before pulmonary valve replacement was 0.55 ± 0.12 and remained unchanged after operation (0.54 + 0.06) (p = NS) (Fig. 5). Exercise tolerance. All seven patients demonstrating improvement in right ventricular ejection fraction after valve insertion noted a subjective improvement in exercise tolerance. Of the four patients without a change in ejection fraction, two were unchanged symptomatically, one patient felt subjectively improved, and one was too young for evaluation.
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Pulmonary valve replacement
Fig. 2. Chest roentgenograms demonstrating reduction in heart size before (Aj and after (Bj pulmonary valve
replacement. Dysrhythmias. Prior to pulmonary valve replacement, four patients had Grade 0, one each Grade 2 (isolated premature ventricular beats) and Grade 3 (multiform premature ventricular beats), and four patients had Grade 4 (successive premature ventricular beats) dysrhythmias according to the Lown criteria. Although repeat 24 hour Holter monitoring has not been routinely performed, no patient has demonstrated an improvement in the grade of dysrhythmia after operation as judged by standard surface electrocardiograms. Discussion Residual abnormalities of the right ventricular outflow tract are common following repair of tetralogy of Fallot. Liberal use of transannular patches has been recommended by some to avoid leaving significant outflow tract obstruction as a result of a hypoplastic pulmonary valve anulus.'? As pulmonary insufficiency is considered to be well tolerated,":" enlargement of the pulmonary anulus seemed preferable to leaving residual stenosis. 15 Thus, large numbers of patients have been left with the obligatory pulmonary insufficiency that results from transannular patching. Although the follow-up of these patients has been generally good, some reports have raised questions regarding the effect that longstanding, severe pulmonary insufficiency has on cardiac function.":" It has become increasingly recognized that, despite otherwise satisfactory hemodynamic repairs, a small percentage of patients with isolated, severe pulmo-
nary insufficiency undergo progressive right ventricular dilatation and failure." When pulmonary insufficiency coexists with other hemodynamic abnormalities such as stenosis or atresia of one pulmonary artery or residual ventricular septal defect, the combination may be particularly disabling. 21 Long-standing severe pulmonary insufficiency may result in impaired right ventricular function from volume overload. This situation may be similar to the effect that chronic aortic insufficiency has on left ventricular function. The occurrence of right ventricular failure may take longer to become apparent compared with left ventricular failure because of the normally lower pressure and resistance in the pulmonary circulation. The added effects of an already abnormal right ventricle in tetralogy of Fallot (hypertrophy, conduction disturbances, and incision and resection of muscle during repair) are difficult to measure but surely contribute. In addition to myocardial dysfunction, progressive right ventricular dilatation may lead to the development of tricuspid regurgitation. As noted by Misbach, Turley, and Ebert I as well as Shaher and colleagues,' a vicious circle results with the rapid development of symptoms. In a previous report from this institution, longstanding pulmonary insufficiency was shown to have an adverse effect on both right and left ventricular function following repair of tetralogy of Fallot," Decreased right and left ventricular ejection fractions were found in a group of patients with isolated severe pulmonary insufficiency compared with those patients without regurgita-
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.40 .30 .20 .10
• • •
Fig. 4. Right ventricular ejection fraction.
tion, despite hemodynamically satisfactory repairs in both groups. All of these patients were without symptoms. In another report, the occurrence of dysrhythmias following repair of tetralogy of Fallot was correlated to ventricular dilatation and function." Patients with ventricular premature contractions had significantly greater right ventricular dilatation and lower left ventricular ejection fractions. Although the incidence of pulmonary insufficiency was not by itself significantly higher in these patients with dysrhythmias, the increased right ventricular dilatation produced by pulmonary insufficiency was believed to be an important factor. The insertion of a prosthesis in the pulmonary position subsequent to complete repair of tetralogy of Fallot has been reported by a number of authors.':'
Fig. 3. Right ventricularIleft ventricular dimension by M-mode echocardiography.
• • •! -•-
Fig. 5. Left ventricular ejection fraction.
Shaher and associates/ reported on 10 patients, nine of whom underwent pulmonary valve replacement for severe insufficiency associated with absent pulmonary artery or impaired right ventricular contractility as judged by cineangiography. Postoperative hemodynamic studies were performed in seven of nine survivors,with improvement shown in five patients. After the elimination of pulmonary insufficiency, marked improvement in right ventricular contractility was noted in the majority of patients. However, measurement of ejection fraction was not reported. The authors consider the finding of impaired right ventricular contractility and aneurysm formation in the right ventricular outflow tract to be the major indication for pulmonary valve replacement when severe pulmonary insufficiency follows repair of tetralogy of Fallot. Misbach, Turley, and Ebert I reported on 12 patients with pulmonary insufficiency who had pulmonary valve replacement for symptoms of progressive right ventricular failure that were unresponsive to medical management. Eleven of these patients demonstrated improvement in symptoms after operation. One patient required subsequent tricuspid valve insertion to alleviate symptoms. Objective improvement in ventricular function was not reported. Our data confirm the usefulness of pulmonary valve replacement in selected patients with significant right ventricular dysfunction secondary to residual pulmonary insufficiency or stenosis. The eight patients with pulmonary insufficiency underwent operation for signs or symptoms of right ventricular failure. The remaining three patients with predominantly pulmonary stenosis were operated on to control severe gradients with or without symptoms. Although this represents a diffuse group with varied indications, in retrospect nearly all the patients had some degree of progressive exercise intoler-
Volume 90 Number 1 July, 1985
ance. Early in our experience we were reluctant to perform pulmonary valve replacement for symptoms alone, without more objective data that demonstrated right ventricular dysfunction. Increasing experience with radionuclide ventriculography for evaluation of right ventricular ejection fraction has allowed better detection and quantification of impaired function in these patients. Encouragingly, this technique has also objectively demonstrated that right ventricular function can improvefollowing pulmonary valve replacement as it did in the majority of our patients. Any possible influence of right ventricular outflow tract plication or excision in the postoperative calculation of right ventricular ejection fraction was minimized by the avoidance of these procedures during pulmonary valve replacement. Although this area was reincised during the operative procedure, it was not surgically reduced and, in fact, was often further enlarged with a prosthetic patch to facilitate placement of a large tissue valve. Serial measurement of right ventricular ejection fraction with radionuelide techniques may allow early detection of patients with worsening function before the onset of symptoms. In these selected patients earlier pulmonary valve replacement may preserve right ventricular function.
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repair of tetralogy of Fallot. J THORAC CARDIOVASC SURG 85:691-696, 1983 9 Jellinek MV, Lown B: Exercise stress testing for exposure of cardiac arrhythmias. Prog Cardiovasc Dis 16:497-522, 1974 10 Arciniegas E, Farooki ZQ, Hakimi M, Perry BL, Green EW: Early and late results of total correction of tetralogy of Fallot. J THORAC CARDIOVASC SURG 80:770-778, 1980 11 Jones EL, Conti CR, Neill CA, Gott VL, Brawley RK, Haller JA: Long-term evaluation of tetralogy patients with pulmonary valvular insufficiency resulting from outflowpatch correction across the pulmonic annulus. Circulation 48:Suppl 3:11-18, 1973 12 Calder AL, Barratt-Boyes BG, Brandt PW, Neutze JM: Postoperative evaluation of patients with tetralogy of Fallot repaired in infancy. J THORAC CARDIOVASC SURG 77:704-720, 1979 13 Finnegan P, Haider R, Patel RG, Abrams LD, Singh SP: Results of total correction of the tetralogy of Fallot. Br Heart J 38:934-942, 1976 14 Fuster V, McGoon DC, Kennedy MA, Ritter DG, Kirklin JW: Long-term evaluation (12 to 22 years) of open heart surgery for tetralogy of Fallot. Am J Cardiol 46:635-642, 1980 15 Poirier RA, McGoon DC, Danielson GK, Wallace RB, Ritter DG, Moodie DS, Wiltse CG: Late results after repair of tetralogy of Fallot. J THORAC CARDIOVASC SURG 73:900-908, 1977 16 Yankah AC, Sievers HH, Lange PE, Regensburger D, Bernhard A: Surgical repair of tetralogy of Fallot in adolescents and adults. Thorac Cardiovasc Surg 30:69-74, 1982 17 Piccoli GP, Dickinson DF, Musumeci F, Hamilton 01: A changing policy for the surgical treatment of tetralogy of Fallot. Early and late results in 235 consecutive patients. Ann Thorac Surg 33:365-373, 1982 18 Wessel HU, Cunningham WJ, Paul MH, Bastanier CK, Muster AJ, Idriss FS: Exercise performance in tetralogy of Fallot after intracardiac repair. J THORAC CARDIOVASC SURG 80:582-593, 1980 19 Graham TP, Cordell D, Atwood GF, Boucek RJ, Boerth RC, Bender HW, Nelson JH, Vaughn WK: Right ventricular volume characteristics before and after palliative and reparative operation in tetralogy of Fallot. Circulation 54:417-423,1976 20 Kirklin JW, Blackstone EH: Editorial on papers by Naito, Wessel, and their colleagues. J THORAC CARDIOVASC SURG 80:594-599, 1980 21 Lange PE, Onnasch DW, Bernhard A, Heintzen PH: Left and right ventricular adaptation to right ventricular overload before and after surgical repair of tetralogy of Fallot. Am J Cardiol 50:786-794, 1982 22 Kavey RW, Thomas FD, Byrum CJ, Blackman MS, Sondheimer HM, Hove EL: Ventricular arrhythmias and biventricular dysfunction after repair of tetralogy of Fallot. J Am Coli Cardiol 4: 126-131, 1984