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To determine late patient outcome and homograft durability, we reviewed 326 patients who received aortic (n = 230) or pulmonary (n = 118) cryopreserved homografts for right ventricular outflow reconstruction between January 1985 and October 1993. Patient survival, including operative mortality, 5 years after the operation was similar between the two groups (pulmonary homograft 86%, aortic homograft 80%; p = not significant by log-rank test). However, 5-year freedom from homograft failure was significantly better for pulmonary homografts (94% versus 70%, p < 0.01 by log-rank test). Late calcification was evaluated by chest roentgenography and echocardiography. Overall, 20% of aortic homografts became moderately or severely calcified compared with 4% of pulmonary homografts (p < 0.01). Twenty-six percent of aortic homografts in children 4 years old or younger had moderate or severe obstruction associated with calcification, whereas only 11% of aortic homografts in patients over 4 years of age had calcific obstruction (p < 0.01). No late deaths among patients receiving pulmonary homografts were related to graft failure; two late deaths in the aortic homograft group were homograft related. Risk factors for patient mortality and homograft failure (defined as either need for homograft replacement because of homograft failure or as homograft-related death) were identified by the Cox multivariate analysis. Aortic type of homograft was a significant risk factor for homograft failure (p < 0.0001), but type of homograft was not correlated with patient mortality. Age 4 years or younger was a significant risk factor for both mortality (p < 0.01) and homograft failure (p = 0.03) in aortic homograft recipients but not in pulmonary homograft recipients. These results indicate that both aortic and pulmonary homografts provided excellent intermediate-term patient survival after right ventricular outflow tract reconstruction, but pulmonary homografts are more durable than aortic homografts with less calcification and obstruction, especially among children 4 years old or younger.

From April 1972 to February 12, 1991, 189 patients with Ebstein's anomaly underwent repair. Ages ranged from 11 months to 64 years (median 16 years, mean 19.1 years). In 58.2%, tricuspid valve reconstruction was possible, and in 36.5%, a prosthetic valve, usually a bioprosthesis, was inserted. In 5.3%, a modified Fontan or other procedure was performed. There were 12 hospital deaths (6.3%). All 28 patients who had accessory conduction pathways (Wolff-Parkinson-White syndrome) underwent successful ablation of the pathways as part of the operative treatment. Follow-up was obtained in 151 (85.3%) patients. Of those patients followed up more than 1 year after operation, 92.9% were in New York Heart Association class I or II. There were 10 late deaths: seven cardiac (four sudden), two noncardiac, and one of an unknown cause. Postoperative Doppler echocardiographic assessment showed the atrial septum was intact in all patients and tricuspid valve function was good to excellent in most patients. Four of the 110 patients (3.6%) who underwent valve reconstruction required reoperation 1.4 to 14.1 years later. Postoperative reduction in heart size was usual, atrial arrhythmias were reduced, and late postoperative exercise testing showed a significant improvement in performance: Maximal oxygen consumption increased from a mean of 47% of predicted value before the operation to a mean of 72% after the operation. Nine patients had a total of 12 successful pregnancies with deliveries of normal children.

In patients with pulmonary atresia and ventricular septal defect, hypoplasia of the central pulmonary arteries prevents single-stage complete repair. Over an interval of 8 1/2 years, 105 patients underwent establishment of continuity between the right ventricle and a hypoplastic central pulmonary arterial confluence (first stage). There were 12 hospital deaths (11%) and 11 late deaths before second-stage (complete) repair. Twenty-five patients await late evaluation. The remaining 57 individuals have had follow-up cardiac catheterization a mean of 33 months postoperatively. In 31 of these, final repair was deferred because of insufficient pulmonary arterial enlargement (14), restricted peripheral arborization (nine), or both (eight). The final 26 patients were accepted for second-stage repair, which has been performed in 24. Complete repair included ventricular septal defect closure (24), right ventricular outflow tract reconstruction (18), relief of central pulmonary arterial stenosis (14), and ligation of systemic-pulmonary collateral arteries (10). The mean postrepair peak systolic right ventricular-left ventricular pressure ratio was 0.67 (range 0.32 to 1.0). One of these patients (4%) died in the hospital and there was one late death (4%) from sepsis after tricuspid valve replacement. Three patients were lost to follow-up; the remaining 19 patients are in functional Class I or II. A two-stage surgical approach is highly successful in those patients whose pulmonary arteries are too hypoplastic to allow a single-stage repair.

A palliative operation to create intraatrial transposition of venous return without concomitant closure of an associated ventricular septal defect (palliative Mustard or Senning operation) has been used primarily for patients with a combination of transposition of the great arteries, ventricular septal defect, and pulmonary vascular obstructive disease. We evaluated the results in all 15 patients (median age 13 years) who had this procedure at the Mayo Clinic between 1973 and 1979. There were two (13%) operative deaths. One patient was lost to long-term follow-up. Of the 12 operative survivors for whom follow-up data were available, 11 reported subjective improvement in exercise tolerance and activity level. There were seven late deaths: six from cardiovascular problems and one from an accident. There are five survivors currently alive (average 10.8 years after operation). Patients who survived the operation for more than 5 years had a significantly (p less than 0.05) lower pulmonary resistance preoperatively than those who survived less than 5 years. The hemoglobin level decreased from 21.1 gm/dl before operation to 18.4 gm/dl, and arterial saturation was increased from 64% to 85% at an average of 9 years after operation. We conclude that this operation produces subjective improvement and lessens hypoxemia and polycythemia. In some patients, palliation may be achieved for 10 years or longer.

At the Mayo Clinic from September 1967, to November 1972, 128 patients underwent operations in which an aortic homograft was used to establish right ventricle-to-pulmonary artery continuity. Recently, we studied 18 of these patients who had calcified, obstructed aortic homografts. Seven patients had histories of significant dysrhythmias, all of which required medication and two of which were life threatening. Seventeen of the patients had systemic or suprasystemic pressure in the right ventricle before replacement of the calcified homografts. After placement of the homograft with a Hancock prosthesis, the pressure in the right ventricle of 12 patients was one half the systemic pressure or less. There were no operative deaths, and only 2 patients developed any significant postoperative problems.

The current status of the septation procedure for univentricular heart was assessed by analyzing the outcomes of 45 procedures done from 1973 through June of 1978. The hospital mortality was 21 (47%) of 45 patients, and eight (18%) patients died during follow-up. Of the 16 survivors, 12 have a fair-to-good surgical result and four are doing poorly. Only two factors were significantly related to increased survival: no history of congestive failure and no previous palliative procedure. Multivariate analysis revealed a small subgroup of 11 patients with a survival rate of 82%. These patients had a subaortic chamber to the left, no previous congestive failure, no previous palliation, and no profound polycythemia, and they were between 5 and 15 years of age at operation. Current practice now employs the Fontan procedure for patients with univentricular heart and low pulmonary artery pressure and resistance. However, nearly half of the patients with univentricular heart will not qualify for a Fontan procedure. For a selected group of these patients, septation must be considered because of the poor long-term outlook for patients with univentricular heart who do not undergo operation.

A review is made of all Mayo Clinic cases wherein 468 patients have received 516 extracardiac conduits in the repair of congenital heart defects. All patients had complex defects, which are classified in 10 basic diagnostic categories. The early mortality rate (which ranged from 4% to 49%, according to diagnostic group) averaged 25%, improving with experience. The postoperative complication rate was 70%. In 1% of operations, compression of the conduit was encountered at chest closure. The conduits placed in 333 patients contained a porcine valve. The conduit diameter averaged 22 mm. At completion of the operation, the mean gradient across the conduit was 22.8 mm Hg. At late study this mean gradient remained at 26 mm Hg in patients who had received the currently employed porcine-valved conduit. The average ratio of intraoperative postrepair ventricular (RV/LV) systolic pressures was 0.68. It was lower among the group who were to survive but was not ov prognostic value in individual cases. Among patients who survived the postoperative period, the late mortality rate (based on a mean of 3.6 years' follow-up) averaged 3.5% per year. Of the long-term survivors, 18% have required reoperation, primarily for replacement of calcified aortic homograft conduits used in the earlier part of the experience. Only 0.8% of porcine-valved conduits have required reoperation. Unrestricted life-styles were possible for 90% of survivors.

The influence on the Frank vectorcardiogram of anatomic features in common ventricle was analyzed by comparison of Frank vectorcardiograms in 51 patients who had common ventricle with those of 36 patients who had large ventricular septal defect, 14 of whom had levotransposition of the great arteries and 22 of whom had dextrotransposition. Frank vector loops in common ventricle differed from those in ventricular septal defect by the frequent occurrence of clockwise horizontal rotation, most common in patients with type C common ventricle (no outflow chamber). There was a statistically significant difference in the amplitude of early forces between patients with common ventricle and those with large ventricular septal defect. The degree of overlap of vectorcardiographic features between the two groups is sufficiently great that the vectorcardiogram has limited usefulness in establishing the diagnosis of common ventricle in any individual patient.

Fifty-nine patients had corrective operation of the Rastelli type for transposition of the great arteries between 1968 and 1975. In 121 patients (35 per cent), the ventricular septal defect was enlarged by excising a portion of the septum. During the first 30 days after the operation, II patients (19 per cent) died. The risk of repair in infancy was greatly increased. There were 5 late deaths, and reoperation was required in 11 patients. Sixty-eight per cent of the survivors are in New York Heart Association Class I and 29 per cent are in Class II. Some late complications related to deteriorations of the earlier aortic homograft conduit may be avoided by use of a Dacron conduit with a porcine valve, as suggested by short-term favorable results in 25 recent cases. The current operative mortality rate of 8 per cent (last 25 operations) and the observation that all but one of the late survivors in this series are either asymptomatic or only mildly symptomatic tend to verify the Rastelli operation as the procedure of choice for repair of transposition of of the great arteries when associated with ventricular septal defect and pulmonary stenosis.

From 1982 to 1987, 38 consecutive patients with pulmonary atresia and ventricular septal defect underwent staged unifocalization procedures in preparation for final intracardiac repair of the anomaly. Thirty-six patients had concordant visceroatrial, atrioventricular, and ventriculoarterial connections. A central pulmonary artery confluence was present in 19 patients and absent in the remaining group. All patients with central pulmonary arteries had inadequate peripheral pulmonary arterial arborization. Systemic collateral arteries were present in all 38 patients. The objectives of the unifocalization procedures were the interruption of extracardiac sources of pulmonary arterial blood flow, the restoration of segmental, lobar, and pulmonary arterial confluence, the replacement of missing central pulmonary arterial branches, and the creation of a central, accessible source of pulmonary arterial blood flow. A total of 54 unifocalization procedures were performed in the 38 patients. These procedures included 85 permanent connecting anastomoses, 15 temporary anastomoses to the ascending aorta, 13 angioplasty procedures, and 15 modified Blalock-Taussig shunts. Three patients died after unifocalization (two early and one late). By the end of the study, eight patients were still waiting for further unifocalization procedures or angiographic assessment. Four patients were rejected for further surgical treatment because of persistent, uncorrectable defects of the pulmonary arterial arborization pattern. Twenty-three patients underwent complete intracardiac repair with two deaths (one early and one late). Postrepair, intraoperative right ventricular/left ventricular systolic pressure ratio after complete surgical repair ranged from 0.4 to 1.0 (mean = 0.63, standard deviation = 0.14). At the end of follow-up, 21 survivors of complete repair were free of significant symptoms. Unifocalization procedures designed to improve the pulmonary arterial arborization pattern of patients with pulmonary atresia and ventricular septal defect with or without central pulmonary arteries can prepare a significant number of these patients for successful intracardiac repair of the anomaly.

This is a review of the 25 patients with truncus arteriosus who have undergone corrective repair following prior banding of the pulmonary arteries. The early and late mortality rate was 20 percent, which has fallen to 6 percent for the most recent 17 operations. These results indicate that the probability of a successful repair for truncus arteriosus is not reduced for patients who have undergone prior banding of the pulmonary artery. In view of the current high mortality rate for corrective repair of the truncus arteriosus in the infant with refractory congestive failure, these results suggest that initial banding of the pulmonary artery for such infants, with later elective correction, may be an appropriate method of management at this time.

In this series of 13 patients undergoing repair of transposition of the great arteries with ventricular septal defect and pulmonary atresia, the operative risk and postoperative complications were greater than for repair of either transposition of the great arteries with ventricular septal defect and pulmonary stenosis or pulmonary arterial atresia with ventricular defect. Nevertheless, 6 of the 8 survivors improved clinically. Because operative and late mortality and morbidity rates are related to persistent right ventricular hypertension caused primarily by restricted pulmonary arterial outflow, results should be improved by performance of a preliminary systemic-pulmonary artery shunt for patients with hypoplastic pulmonary arteries and by use of the Hancock prosthesis, which has yielded lower gradients at both the proximal and distal anastomoses of the conduit. These improvements and the relief from cyanosis, exercise intolerance, and other symptoms seem to justify the continued application of surgical correction of transposition of the great arteries when associated with pulmonary atresia.

Double-orifice mitral valve is an uncommon but surgically important condition. The experience in 25 cases of double-orifice mitral valve associated with atrioventricular canal defects was reviewed. This constituted 4.3% of the 581 cases of atrioventricular canal defects operated upon between 1961 and July, 1984. The combined mitral orifice area ranged from 85% to 91% of normal in those patients whose valves were sized intraoperatively. Ten associated cardiac defects were repaired in six patients. Of 23 patients having cleft mitral valve, 21 had partial closure of the cleft. There was one operative death (4.0%), which occurred early in the series in a patient in whom the tissue bridge was severed and massive mitral regurgitation resulted. In the remaining 24 patients the tissue bridge was left intact, and all survived operation. No patient had clinically significant mitral stenosis during a follow-up of 1 to 14 years (mean 4.9 years). Two patients (8%) developed progressive mitral regurgitation and required mitral valve replacement 3 and 11 years postoperatively. One of these patients died and a second death occurred suddenly 2 years following operation. All survivors are in Functional Class I or II. The noncleft orifice of a double-orifice mitral valve usually is competent and rarely requires closure. The cleft, because it constitutes a type of parachute (single papillary muscle) valve, should be closed partially so as to relieve valve incompetence without causing undue stenosis. The incidence of late development of mitral regurgitation is similar to that of atrioventricular canal without double-orifice mitral valve. Repair of atrioventricular canal associated with double-orifice mitral valve can be achieved with a low operative mortality and excellent late results.

Five complete conduit occlusions occurred in four patients with the Glenn shunt 2 months to 2 years after the Fontan operation. The possible reasons for complete conduit occlusion were severe dehydration, high pulmonary vascular resistance, and intraoperative manipulation of the conduit. In one patient in whom complete conduit occlusion developed twice, no possible cause could be identified. Surgical approaches included replacement of the occluded conduit in three patients and creation of an atrial septal defect and left aortopulmonary shunt in the fourth patient. All patients who had replacement of the occluded conduit survived. The fourth patient had severe cyanosis and hypoxemia from marked reduction of flow through the Glenn shunt because of reversal of flow through large venous collaterals. He subsequently died of Candida sepsis. A fifth patient (previously reported) who had complete conduit occlusion also died after a similar procedure. We believe that in patients with a Glenn shunt who develop complete conduit occlusion after the Fontan operation, conduit excision and a secondary Fontan operation, preferably without the use of woven Dacron, should be done instead of establishing an atrial septal defect and aortopulmonary shunt to the left lung.

Between Jan. 1, 1970, and Jan. 1, 1980, 62 consecutive patients underwent repair of classic double-outlet right ventricle (DORV). Patients with subpulmonic ventricular septal defect (VSD), complete atrioventricular canal, atrioventricular discordance, and univentricular heart were excluded. One hundred six associated defects were present in 54 patients. Forty-six patients had pulmonary stenosis. The 36 male and 26 female patients ranged in age from 8 months to 37 years (median age 9 years). The early mortality was 11% for those with pulmonary stenosis, 25% for those without pulmonary stenosis, and 15% for the entire series. The risk of mortality was related to the age of the patient at operation. Causes of early deaths included low cardiac output (three patients), high residual right ventricular pressure (three patients), anomalous coronary artery injury (one patient), infection (one patient), and hemorrhage (one patient). Eleven late deaths occurred among the 53 operative survivors (21%). Ten (91%) of the late deaths were attributed to arrhythmia. All except one of the long-term survivors are in Functional Class I or II. Although the operative mortality for the repair of DORV continues to decrease, the late mortality is of concern, and the problem of late arrhythmia necessitates further study and analysis.

Selection of types of prosthetic heart valves for children remains controversial. The case histories of 50 children surviving valve replacement with Starr-Edwards prostheses between 1963 and 1978 were reviewed to evaluate the long-term performance of mechanical valves. The 31 boys and 19 girls ranged from 6 months to 18 years in age (mean 10.4 years); 19 patients had had aortic valve replacement, 24 patients had had mitral valve replacement, and one patient had had both. Among the six patients who had had tricuspid valve replacement, four had corrected transposition, so that the tricuspid valve was the systemic atrioventricular valve. Mean (+/- standard deviation) follow-up interval was 7.9 +/- 4.9 years (maximum 17 years). For all patients, the 5 year survival rate was 86% +/- 6%. At 10 years postoperatively, the survival rate (+/- standard error) was 90% +/- 7% after aortic valve replacement and 76% +/- 8% after systemic atrioventricular valve replacement. At follow-up, 39 patients were alive, and 38 were in New York Heart Association Class I or II. Of the 11 deaths, four were valve-related. Seven patients had major (requiring hospitalization) thromboembolic events, and five patients had minor transient neurological symptoms suggesting thromboembolism; 50% of these patients were not taking warfarin (Coumadin) at the time of the thromboembolic event. The incidence of late (greater than 30 days) thromboembolism was 5.3 per 100 patient-years after aortic and 2.0 per 100 patient-years after systemic atrioventricular valve replacement. At 10 years postoperatively, 66% +/- 15% of patients who had had aortic valve replacement and 91% +/- 6% of those who had had systemic atrioventricular valve replacement were free of thromboembolism. The excellent long-term survival, absence of mechanical failure, and relatively low rate of thromboembolism with this prosthesis contrast with our experience with biological valves, in which 41% of children required reoperation in 5 years. Currently, mechanical valves, such as the Starr-Edwards prostheses, are our preferred valves for pediatric patients.

From 1973 to 1980, 49 patients under 18 years of age survived cardiac valve replacement with Hancock porcine heterografts. Complete follow-up has been obtained on 44 patients (90%) in whom 46 valves were placed. There were 30 boys and 14 girls with an age range of 2 to 18 years (mean 10.0 years). Severe prosthetic valvular dysfunction requiring valve replacement occurred in eight valves in seven patients at 15 to 60 months postoperatively (mean 34.1 months), yielding a calculated replacement rate of 7.1% per patient-year. All eight valves demonstrated severe calcification with stenosis, two valves had significant insufficiency secondary to leaflet disruption, and one valve had a large leaflet perforation. Thirty-one patients with valves in place at 7 to 90 months (mean 38.4 months) are alive, but six have clinical evidence of progressive valvular dysfunction. The mean age at the time of the original Hancock valve placement of the group of patients having undergone replacement of a failed prosthesis together with those with clinical evidence of prosthetic dysfunction was 8.0 years, which is significantly less than that of the remaining group of patients with normally functioning valves (mean 11.2 years, p = 0.043). Actuarial curves demonstrate a predicted replacement-free rate of 87.4% +/- 5.9% at 3 years. 82.3% +/- 7.5% at 4 years, and 58.5% +/- 15.7% at 5 years. On the basis of these data and other reports of early failure in the literature, we have discontinued the routine use of Hancock porcine heterografts for cardiac valve replacement in children in favor of mechanical prostheses.