William T. Mustard

Ventricular septal defect with increased pulmonary vascular resistance: Late results of surgical closure

Abstract The fate of 57 children who underwent surgical closure of ventricular septal defect in the presence of increased pulmonary vascular resistance was analyzed. Eighteen (32 percent) died at or immediately after operation. Seven late deaths, due to the Eisenmenger syndrome, occurred 1 to 7 years after operation. Follow-up studies, including cardiac catheterization, were performed in 25 survivors, 1 to 11 years (mean 5 years) after operation. In patients operated on after age 2 years, the degree of preoperative elevation of pulmonary vascular resistance largely determined the prognosis: The condition of patients with mild elevation (pulmonary vascular resistance less than one third the systemic level) returned to normal after operation, with one exception. Patients with more severe elevation (pulmonary vascular resistance more than one third the systemic level) most often showed progressive pulmonary vascular disease; the condition of a few remained unchanged and that of only one returned to normal after operation. Operative mortality rate was high in children with elevated pulmonary vascular resistance during the second year of life who were operated on before age 2 years, but pulmonary vascular resistance returned to normal in the three survivors. When pulmonary vascular resistance was increased in the first year of life, it generally decreased spontaneously (independently of operation); the early increase in these cases is believed to represent delayed maturation of the pulmonary vascular bed rather than pulmonary vascular disease. The overall results of surgery in ventricular septal defect associated with a high level of pulmonary vascular resistance are unfavorable and call for interruption of the natural history before significant pulmonary vascular obstructive changes have taken place; this can be achieved by surgical closure before age 2 years or pulmonary artery banding in infancy.

Repair of Transposition of the Great Arteries in 123 Pediatric Patients: Early and Long-Term Results

From May 1963 to July 1972, 123 patients ranging in age from 20 days to 15 years, with D-transposition of the great arteries, underwent an intraatrial baffle operation using a pericardial baffle. They previously had had a total of 121 various palliative procedures.Twenty-six children (21%) died in the early postoperative period. The operative mortality was 13% in transposition of the great arteries with intact ventricular septum, 45% in trasnposition of the great arteries plus ventricular septal defect, and 33% in transposition of the great arteries plus ventricular septal defect and left ventricular outflow tract obstruction. By contrast the overall mortality has decreased to 15% in the 72 patients operated upon over the last 2 years.There were 12 late deaths, 10 of which occurred within the first year postoperatively. Unexplained heart failure accounted for four deaths. Two sudden deaths were attributed to arrhythmias. Three patients died of proven pulmonary venous obstruction, one of them at reoperation. Pulmonary hypertension, reoperation for detachment of the baffle, and hypoglycemia were each the cause of one late death. There were no proven cases of tricuspid incompetence.Eighty children have been repeatedly reexamined for up to 8 years and 6 months. The actuarial 6-year survival was 74.8% for survivors of operation.Seventy-three children were leading a normal life at the time of the report.

Pediatric cardiologyVentricular septal defect with increased pulmonary vascular resistance: Late results of surgical closure☆

Abstract The fate of 57 children who underwent surgical closure of ventricular septal defect in the presence of increased pulmonary vascular resistance was analyzed. Eighteen (32 percent) died at or immediately after operation. Seven late deaths, due to the Eisenmenger syndrome, occurred 1 to 7 years after operation. Follow-up studies, including cardiac catheterization, were performed in 25 survivors, 1 to 11 years (mean 5 years) after operation. In patients operated on after age 2 years, the degree of preoperative elevation of pulmonary vascular resistance largely determined the prognosis: The condition of patients with mild elevation (pulmonary vascular resistance less than one third the systemic level) returned to normal after operation, with one exception. Patients with more severe elevation (pulmonary vascular resistance more than one third the systemic level) most often showed progressive pulmonary vascular disease; the condition of a few remained unchanged and that of only one returned to normal after operation. Operative mortality rate was high in children with elevated pulmonary vascular resistance during the second year of life who were operated on before age 2 years, but pulmonary vascular resistance returned to normal in the three survivors. When pulmonary vascular resistance was increased in the first year of life, it generally decreased spontaneously (independently of operation); the early increase in these cases is believed to represent delayed maturation of the pulmonary vascular bed rather than pulmonary vascular disease. The overall results of surgery in ventricular septal defect associated with a high level of pulmonary vascular resistance are unfavorable and call for interruption of the natural history before significant pulmonary vascular obstructive changes have taken place; this can be achieved by surgical closure before age 2 years or pulmonary artery banding in infancy.

Complete transposition of the great vessels with anatomic obstruction of the outflow tract of the left ventricle: Surgical implications of anatomic findings☆

Twenty-three specimens with complete transposition of the great vessels and left ventricular outflow tract obstruction were studied. Two groups emerged: Group I, 12 specimens with an intact ventricular septum, and Group II, 11 specimens with a ventricular septal defect. In Group I valvular stenosis was present in 4, subvalvular fibrous ring in 3 (1 associated with valvular stenosis), and bulging of the septum into the cavity of the left ventricle in 7 (1 associated with valvular stenosis). In Group II pulmonary valvular stenosis was present in all. In addition, 7 specimens also showed bulging of the septum into the cavity of the left ventricle; three showed severe subvalvular fibromuscular obstructions (tunnel type); and 1, a subvalvular fibrous ring or shelf. Whereas a subvalvular fibrous ring or bulging of the septum into the cavity of the left ventricle occurred in those with an intact ventricular septum or with a ventricular septal defect, a subvalvular fibromuscular obstruction (tunnel type) was observed only in those with a ventricular septal defect when this defect was situated at some distance from the pulmonary valve. Bulging of the ventricular septum into the cavity of the left ventricle was thought to be acquired as a result of either hypertrophic reaction of the left ventricle to pulmonary valvular or subvalvular stenosis, or septal hypertrophy secondary to right ventricular hypertrophy. Sufficient hemodynamic data are not available to evaluate the functional significance of bulging of the ventricular septum into the cavity of the left ventricle. Limited hemodynamic data, coupled with anatomic data, suggest that the obstruction is mild to moderate in the majority of cases. In all patients with a ventricular septal defect the pulmonary artery was smaller than the aorta, and it was small enough to create a problem in relation to surgical correction in 5. In those with an intact ventricular septum the pulmonary artery was larger than the aorta in 3, smaller than the aorta in 5, and of equal size in 4. The ventricular septal defect was anterior in 3, posterior in 3, and of the atrioventricular canal type in 5. The anatomy of the coronary artery has been studied in each case, and it was found that the left circumflex artery coursed in front of the outflow tract of the left ventricle in 16 specimens. Left ventricular angiocardiography is of help in demonstrating the type of left ventricular outflow tract obstruction as well as the size of the pulmonary artery. The surgical approach to the associated defects is discussed. For cases with a small pulmonary artery an initial anastomosis between the superior vena cava and the pulmonary artery is recommended. Patients with juxtaposition of the atrial appendages are believed to require a graft or prosthesis to enlarge the right atrium. When the left circumflex artery courses in front of the outflow tract of the left ventricle, relief of the obstruction should be undertaken, preferably through the pulmonary artery or the apex of the left ventricle.

Conduction disturbances after total correction of tetralogy of Fallot

The electrocardiographic (ECG) changes produced at surgery in all patients undergoing total correction of tetralogy of Fallot at the Hospital for Sick Children, Toronto, from 1955 through 1974, were reviewed. Particular attention was directed to the presence of postoperative right bundle branch block combined with left anterior hemiblock because a recent report indicated a 25 per cent late mortality rate in children with this ECG pattern. 1 Data from our institution and others have indicated that the prognosis with this lesion may be better than first reported. -~-4 Methods

Left ventricular myocardial fibroma: A case report and review of cardiac tumors in children

Abstract A 30-mo-old boy had a successful excision of an intramyocardial fibroma. Fibromas constitute about one quarter of the reported primary cardiac tumors in children and offer the best chance of excision. Rhabdomyomas account for over half of childhood cardiac tumors but usually are not diagnosed until they are terminal and nonresectable. Myxomas, which account for 50% of adult tumors, are almost unknown in children.

Tricuspid atresia: Results of treatment in 160 children

Experience in managing 160 patients with tricuspid atresia is reviewed. The majority of these children require operative treatment in the 1st year of life. Clinical management of this rather complex anomaly is simplified by classifying each child according to total pulmonary blood flow. An overall plan of management for patients with decreased pulmonary flow is suggested. This consists of a Potts shunt as an initial procedure, limiting its anastomotic growth so that pulmonary flow becomes inadequate at age 10 to 12 years. A Glenn anastomosis is then constructed as the second procedue. The Fontan procedure should be considered carefully as an alternative to the Glenn anastomosis in these older children. Children with increased pulmonary blood flow and transposition of the great arteries are likely to require pulmonary arterial banding in infancy. Otherwise, patients in this smaller group are managed with the same overall plan. Results of long-term palliation have been good.

Survival after systemic to pulmonary arterial shunts in infants less than 30 days old with obstructive lesions of the right heart chambers

Ninety-seven infants less than 30 days old with obstructive lesions of the right heart chambers underwent palliative surgery from 1950 through 1972. The diagnosis was made at cardiac catheterization and confirmed at operation or subsequent autopsy. Because of unavailability of complete preoperative studies and sufficient blood gas data, 36 patients presenting between 1950 and 1965 (Group I) were analyzed for surgical risk only. In 61 patients who underwent palliative procedures between 1966 and 1972 (Group II) a more detailed analysis was done. In this group, 31 had a Potts shunt, 29 a Waterston shunt and 1 a Blalock-Taussig shunt. The most frequently encountered malformation was severe tetralogy of Fallot (30 percent) with or without pulmonary atresia, followed by pulmonary atresia with intact ventricular septum (25 percent). The overall surgical mortality rate in patients seen after 1965 (Group II) was 34 percent compared with the 78 percent mortality rate in patients seen earlier (Group I). The surgical mortality in infants operated on during the 1st week of life was double that of those operated on in the 2nd through 4th weeks. Survivors were compared with nonsurvivors for timing of surgery, age at presentation and clinical profile. Only two significant differences were found. Preoperative continuous murmurs were more common in those who survived operation (13 of 40 patients) than in those who died (2 of 21). Arterial pH during cardiac catheterization was the best predictor of subsequent survival, nonsurvivors having significantly greater metabolic acidosis. Palliation of these severe lesions still carries a high mortality rate to which must be added the risk of subsequent repair. Our data suggest that primary repair is to be preferred if it can be undertaken with a risk approximating that of palliative procedures.

Hemodynamic Effects of a Totally Corrective Procedure in Transposition of the Great Vessels

1. The hemodynamic findings in four children with transposition of the great vessels who have been completely corrected are described and contrasted with the findings before and after the initial creation of an atrial septal defect.2. All four cases exhibit full arterial oxygen saturation and have normal atrial pressures. The pressure tracings in the atria suggest that the pericardial baffle does not interfere with their function.3. It is suggested that the left ventricle in transposition of the great vessels may assume the compliance characteristics of a normal right ventricle.4. It is concluded that with this procedure it is possible to restore normal cardiac function and systemic oxygenation in childrenwith complete transposition of the great vessels.