Long-term survival of aortic atresia following biventricular corrective surgery

A female born with aortic atresia, large ventricular septal defect, normal mitral valve, and left ventricle is well at 21 years of age following biventricular repair. She had palliative surgery at 15 days and closure of ventricular septal defect with placement of a valved conduit from the left ventricular apex to descending aorta at 15 months. Conduit was replaced at 34 months and at 10 and 21.5 years of age.

The left-sided aortic arch in humans, viewed as the end-result of natural selection during vertebrate evolution

At some point during vertebrate evolution from species dwelling in water to living on land, the ancestral double or right aortic arches became single and left-sided in mammals, including humans, as the result of synchronous developments in cardiovascular and respiratory embryogenesis. Since left-sided aortic arches are unique to mammals, hemodynamics related to the placenta, specifically the requirement for a large arterial duct connecting to the descending aorta, may have led to switching from the right-sided to the left-sided arch. Additionally, development of a trilobar right lung and its bronchial tree, also unique to mammalian evolution, restricted the space above the high eparterial bronchus to a single large vessel. Consequently, mammals that mutated to the left-sided aortic arch avoided respiratory, digestive or circulatory problems that are often associated with an isolated right-sided aortic arch--something which could be considered a successful mistake. Due to natural selection, and survival of the fittest, the left-sided arch became the norm in mammals. In congenital cardiac malformations where a large arterial duct is not mandatory in fetal life, as in Fallot's tetralogy or common arterial trunk, a right-sided aortic arch continues to occur, perhaps as an atavistic reversion to the anatomy seen in ancestral vertebrates.

Echocardiographic Doppler evaluation of left ventricular diastolic filling in older, highly trained male endurance athletes

Previously published data have suggested that endurance training does not retard the normative aging impairment of early left ventricular diastolic filling (LVDF). Those studies, suggesting no effect of exercise training, have not examined highly trained endurance athletes or their LVDF responses after exercise. We therefore compared LVDF characteristics in a group of older highly trained endurance athletes (n = 12, mean age 69 years, range 65-75) and a group of sedentary control subjects (n = 12, mean age 69 years, range 65-73) with no cardiovascular disease. For all subjects, M-mode and Doppler echocardiographic data were obtained at rest. After baseline studies, subjects underwent graded, maximal cardiopulmonary treadmill exercise testing using a modified Balke protocol. Breath-by-breath respiratory gas analysis and peak exercise oxygen consumption (VO(2)max) measurements were obtained. Immediately after exercise and at 3-6 minutes into recovery, repeat Doppler echocardiographic data were obtained for determination of LVDF parameters. VO(2)max (44 +/-6.3 vs 27+/-4.2 ml/kg/min, P<0.001), oxygen consumption at anaerobic threshold (35+/-5.4 vs 24+/-3.8 ml/kg/min, P<0.001), exercise duration (24+/-3 vs 12+/-6 minutes, P<0.001), and left ventricular mass index (61+/-13 vs 51+/-7.8 kg/m(2), P<0.05) were greater in endurance athletes than in sedentary control subjects, whereas body mass index was lower (22+/-1.7 vs 26+/-3.4 kg/m(2), P<0.001). No differences in any of the LVDF characteristics were observed between the groups with the exception of a trend toward a lower atrial filling fraction at rest in the endurance athlete group versus the control subjects (P = 0.07). High-intensity endurance exercise training promotes exceptional peak exercise oxygen consumption and cardiovascular stamina but does not appear to alter normative aging effects on left ventricular diastolic function.

Bidirectional Glenn shunt in association with congenital heart repairs: the 1(1/2) ventricular repair

BACKGROUND

The bidirectional Glenn shunt has been used to incorporate a smaller tripartite ventricle into the circulation and create pulsatile pulmonary artery flow. We reviewed our operative experience and assessed hemodynamics of the bidirectional Glenn shunt in 1(1/2) ventricular repair or in conjunction with other repairs of congenital heart defects.

METHODS

Between 1992 and 1998, 15 patients (mean age, 8.1+/-7.9 years) had bidirectional Glenn shunt in association with repair of congenital heart defects. Eighty-seven percent had at least one previous operation. All patients had simultaneous or previous intracardiac repair and had bidirectional Glenn shunt to volume unload the small right ventricle (group A, n = 7), to unload the poorly functioning right ventricle (group B, n = 2), to redirect superior vena cava-pulmonary venous atrial connection to treat cyanosis (group C, n = 2), or to unload the pulmonary left ventricle for residual intracavitary hypertension in patients with L-transposition of the great arteries, ventricular septal defect, and pulmonary stenosis (group D, n = 4). Intraoperative hemodynamic assessment was done in 2 patients in group A by selective use of inflow occlusion and flow probes.

RESULTS

All patients survived. Four patients had successful, concurrent arrhythmia circuit cryoablation for Wolf-Parkinson-White syndrome (n = 1) or atrial reentry tachycardia (n = 3). Superior and inferior vena caval flow averaged 36% and 64% of cardiac output, respectively. Postoperative superior vena caval pressure (n = 13) was 13.7+/-4.0 mm Hg with pulmonary arterial flow pattern contributed by the ventricle in systole (pulsatile) and the superior vena cava in diastole (laminar).

CONCLUSIONS

The bidirectional Glenn shunt is an effective adjunct to congenital heart repair to treat pulmonary ventricular pressure-volume problems and anomalous superior vena caval to left atrial connections.

Is surgical ligation of an accessory left superior vena cava always safe?

In patients considered for bidirectional Glenn or Fontan procedures, the association of left superior vena cava (LSVC) with ostial atresia of the coronary sinus should be diagnosed preoperatively in order to avoid surgical division or ligation of the LSVC and the negative effect of resulting coronary venous hypertension on myocardial perfusion. This report discusses the angiographic and hemodynamic features of LSVC when it is the only drainage route from a blind coronary sinus. A retrograde flow in the LSVC seen by Doppler ultrasonography should raise the suspicion of this diagnosis.

Coronary artery fistulas in infants and children: a surgical review and discussion of coil embolization

BACKGROUND

Coronary artery fistula (CAF) is a rare congenital anomaly that can be complicated by intracardiac shunts, endocarditis, myocardial infarction, or coronary aneurysms. Recent reports have emphasized the efficacy of percutaneous transcatheter techniques. The purpose of this article is to review a 28-year surgical experience with CAF as a standard for comparison and to discuss the emergence and efficacy of transcutaneous catheter coil embolization as an alternative form of therapy.

METHODS

From 1968 to 1996, 17 patients (age, 6 weeks to 16.5 years; mean age, 5.5 years) were diagnosed with CAF: 8 of 12 by echocardiography and 17 of 17 by cardiac catheterization. All patients with isolated CAF (n = 13) were asymptomatic despite significant clinical, electrocardiographic, and chest roentgenographic findings in 10. Sixteen had congenital CAF and 1 had acquired CAF after tetralogy of Fallot repair with injury of the anomalous left anterior descending coronary artery. Associated anomalies included tetralogy of Fallot (2), atrial septal defect (1), and patent ductus arteriosus (1). Nine fistulas originated from the right coronary artery and eight from the left. Drainage was to the right ventricle (9), right atrium (4), pulmonary artery (3), and left atrium (1).

RESULTS

All patients had a median sternotomy with epicardial or endocardial ligation. Cardiopulmonary bypass was used in 8; 1 of these (iatrogenic CAF) required distal internal mammary artery bypass graft. There were no operative or late deaths. Follow-up evaluation by physical examination (17), echocardiography (8), and catheterization (2) showed no evidence of recurrent or residual CAF. A retrospective review of the 16 available cine cardioangiograms showed that coil embolization was possible in, at most, 6 patients.

CONCLUSIONS

Early surgical management of CAF is a safe and effective treatment resulting in 100% survival and 100% closure rate. Transcatheter embolization is a reasonable alternative to standard surgical closure in only a very small, select group of patients. These surgical results should be considered the standard against which transcatheter techniques are compared.

Taussig-Bing anomaly: arterial switch versus Kawashima intraventricular repair

BACKGROUND

Current corrective surgical approaches for the Taussig-Bing heart include arterial switch with ventricular septal defect (VSD) closure and intraventricular repair as described by Kawashima.

METHODS

Between 1983 and 1994, 20 children underwent intracardiac repair of Taussig-Bing anomaly. Mean age at operation was 17 months (range, 1 week to 9 years). Prior palliation included pulmonary artery band (15) with coarctation repair (8) and atrial septectomy (1). Arterial switch with VSD closure was performed in 16 patients, 10 with anteroposterior great arteries. Kawashima repair was performed in 4 patients, all with side-by-side great arteries.

RESULTS

After arterial switch, there was one operative death (6.2%) due to myocardial ischemia and three late deaths (18.7%) due to pulmonary hypertension, gastrointestinal bleeding, and acute lymphocytic leukemia. In the Kawashima repair group there have been no deaths. After arterial switch, 9 patients underwent 11 reoperations for residual coarctation (3), residual pulmonary artery stenosis (2), aortic valve replacement, aortic valvuloplasty, unrecognized VSD, mitral valvuloplasty, mediastinitis, and pacemaker insertion. After Kawashima repair, 1 patient underwent reoperation for baffle stenosis and 1 for an unrecognized VSD.

CONCLUSIONS

For children with Taussig-Bing anomaly, the Kawashima intraventricular repair (for side-by-side great arteries) preserves the native aortic valve and avoids coronary dissection. The arterial switch operation with VSD closure can be applied without ventriculotomy to all great artery relationships and allows neonatal repair with or without concomitant coarctation repair. Both techniques yield excellent early and intermediate-term results despite the high rates of prerepair palliation and postrepair reoperation for both groups.

Double-horned or caplike right ventricle: diagnosis and operative treatment

BACKGROUND

Three patients reported here and 4 from the literature serve as background for the state-of-art diagnostic and operative considerations for an unusual congenital cardiac malformation: double-horned or caplike right ventricle.

METHODS

This is a retrospective analysis of cardiac catheterization, cineangiography, and two-dimensional echocardiography findings, as well as palliative and corrective operations in 3 previously unreported patients. Four patients from the literature are reviewed.

RESULTS

Characteristic morphologic features recognizable by invasive and noninvasive imaging distinguish double-horned right ventricle from complex malformations such as criss-cross hearts, superior-inferior ventricles, and univentricular hearts with a small outflow chamber.

CONCLUSION

Double-horned or caplike right ventricle is a congenital malformation characterized by an unusual ventricular morphology, which may be the result of incomplete development of the right ventricle. The two-horned appearance may be secondary to an absence of the apical trabeculated compartment, with the left ventricle wedged between the two horns. It is invariably associated with double right ventricular outlet. Surgical experience so far suggest that most patients with typical double-horned right ventricle should be considered for anatomic surgical correction.

Expanding indications for pediatric coronary artery bypass

Pediatric coronary artery bypass has been done mostly for ischemic complications of Kawasaki disease. We reviewed our clinical experience between 1987 and 1994 with internal thoracic artery-coronary artery bypass in one infant and five children for varying indications. Indications for coronary bypass included Kawasaki disease (2), congenital left main coronary ostial stenosis, iatrogenic coronary cameral fistula, anomalous origin of the left coronary artery from the pulmonary artery, and single coronary artery traversing between the great arteries in a patient after cardiac transplantation. An additional cohort of 34 control patients of various ages and weights (1 day to 16.1 years, 2.6 kg to 62 kg) had angiographic measurements of the right coronary, left coronary, and left internal thoracic arteries with respect to the feasibility of performing coronary artery bypass. All six patients survived internal thoracic artery-left anterior descending coronary artery bypass without evidence of perioperative myocardial infarction. Postoperative angiographic studies in five and color Doppler echocardiography in one showed graft patency. Retrospective angiographic measurements in the 34 control patients showed that internal thoracic and coronary arteries are proportionately quite large in neonates and infants compared with those in older children and adolescents. Internal thoracic artery-coronary artery bypass should be considered for the expanding indications presented herein and when emergency intraoperative life-threatening situations present themselves. Long-term patency and reoperation rates have yet to be determined.

Coarctation of the abdominal aorta

Four patients with suprarenal coarctation of the abdominal aorta were managed from 1978 to 1993 (mean follow-up 8.75 years). Ages at the time of diagnosis were 2 months, 8 months, 4.5 years, and 15 years, respectively. Three children presented with severe hypertension, two of whom were in congestive heart failure, and the fourth child presented with a cold, ischemic leg. The 8-month-old patient had Williams syndrome (supravalvular aortic and pulmonic stenosis, bilateral renal artery stenosis and celiac artery occlusion, "elfin" facies, and mental retardation) and was treated nonoperatively. After 12 years of follow-up, he was given five medications to control hypertension, cardiac arrhythmias, and heart failure. Three patients with abdominal aortic coarctation were treated operatively and none died. Two patients underwent bypass grafting from the supraceliac aorta to the infrarenal aorta, with bilateral renal artery reconstruction in one. Postoperative arteriograms obtained 1 year or more after operation were normal in both cases. The 2-month-old patient underwent patch aortoplasty, with subsequent reoperation 1.5 years later for recurrent hypertension and heart failure with a bypass graft to the left kidney and removal of an infarcted right kidney. In all three patients, operative repair of the suprarenal aortic coarctation has resulted in long-term control of blood pressure and cardiac and renal function.

Normal left ventricular muscle mass and mass/volume ratio after pediatric cardiac transplantation

BACKGROUND

The adaptive growth of the transplanted heart within the growing child may contribute to long-term cardiac performance. The ability to achieve increased ventricular volume and appropriate muscle mass in the face of immunosuppression and cardiac denervation has not been studied. We previously reported normal left ventricular (LV) volume growth over a 3-year period after cardiac transplantation. This study was designed to assess changes in LV mass and mass/volume ratio and their relation to LV end-diastolic pressure (LVEDP) 1 to 4 years after cardiac transplantation.

METHODS AND RESULTS

Cardiac transplantation was performed in 18 patients, age 7 days to 18 years (median, 3.7 years). The indications for cardiac transplantation were cardiomyopathy (8 patients), hypoplastic left heart syndrome (7 patients), and postoperative structural congenital heart disease with ventricular failure (3 patients). The mean follow-up was 48 months, with a range from 29 to 70 months. Serial annual catheterizations were performed after 1 year (16 patients), 2 years (18 patients), 3 years (15 patients), and 4 years (8 patients). Cardiac index (Fick), LVEDP (baseline and after 10-mL/kg saline infusion delivered over 5 minutes), and systemic vascular resistance (SVR) were measured. LV diastolic volume index (LVDVI), LV mass index, and mass/volume ratio were determined angiographically according to the method of Lange and Rackley. The data were analyzed by repeated-measures ANOVA. Least-squares means and group SEM were calculated. No change in cardiac index, SVR, or baseline LVEDP was noted. The LVEDP doubled after fluid challenge, suggesting a restrictive process. The LVDVI remained near 60 mL/m2. The LV mass/volume ratio remained one.

CONCLUSIONS

Appropriate increases in muscle mass occurred after cardiac transplantation, preserving normal mass/volume ratios despite somatic growth deficits associated with immunosuppressive therapy and denervation of the donor heart.

Restrictive ventricular septal defect: how small is too small to close?

Historically, indications for ventricular septal defect closure have included congestive heart failure, pulmonary hypertension, aortic insufficiency with or without aortic valve prolapse, and prior bacterial endocarditis. However, controversy exists as to how the lifetime risk of an isolated, nonoperated restrictive ventricular septal defect compares with the risk of surgical closure in an asymptomatic child. Between 1980 and 1991, cardiac catheterization and elective ventricular septal defect closure (age > 1 year, pulmonary to systemic flow ratio < 2.0) were performed in 141 patients aged 1 to 23 years (mean age, 6.1 +/- 4.7 years). Mean systolic pulmonary artery pressure was 26.9 +/- 13.0 mm Hg, and mean pulmonary to systemic flow ratio was 1.6 +/- 0.3. Aortic valve prolapse was present in 63 patients (45%), aortic insufficiency was present in 25 (18%), and 5 (3.5%) had prior bacterial endocarditis. There were no early or late deaths or major morbidity. No patient required a ventriculotomy to accomplish ventricular septal defect closure. Mean postoperative intensive care unit stay was 1.3 +/- 0.9 days, and mean hospital stay was 5.5 +/- 1.9 days. There were no instances of permanent complete atrioventricular dissociation, reoperations for bleeding, postoperative wound infections, or reoperations for residual or recurrent ventricular septal defect. These improved results justify a reevaluation of historic indications for ventricular septal defect closure.(ABSTRACT TRUNCATED AT 250 WORDS)

Failure of the Hemashield extension in right ventricle-to-pulmonary artery conduits

Between 1989 and 1991, 17 children underwent 18 right ventricle-to-pulmonary artery conduit placement operations using a composite of an aortic or pulmonary valved homograft and a Hemashield extension to the ventricle. Hemashield is a collagen-coated knitted Dacron graft with excellent compliance and hemostatic properties. Diagnoses included tetralogy of Fallot with pulmonary atresia (7), truncus arteriosus (6), and complex transposition of the great arteries (4). Mean age at conduit placement was 4.9 +/- 4.2 years, and all patients survived. At a mean follow-up of 14 +/- 4 months, postoperative Doppler echocardiographic gradients between the ventricle and pulmonary artery ranged from less than 20 to 60 mm Hg. At cardiac catheterization 13 +/- 3 months postoperatively (6 patients), the systolic pressure gradient across the conduits ranged from 14 to 90 mm Hg (mean gradient, 59 +/- 29 mm Hg). Conduit obstruction, when present, was demonstrated angiographically to be in the Hemashield portion and led to early conduit replacement six times in 5 patients (33% of operations) within 10 to 18 months (mean time, 14 months) after insertion of the original conduit. Pathologic examination of the explanted conduits revealed the obstruction to be a thick neointimal peel that was impossible to separate from the Hemashield graft. Failure of the Hemashield as an extension for ventricle-to-pulmonary artery conduits secondary to accelerated neointimal formation has led us to abandon its use in clinical practice.

Biventricular repair of hypoplastic right ventricle assisted by pulsatile bidirectional cavopulmonary anastomosis

The right ventricle in patients with severe outflow obstruction or atresia and a small tricuspid valve often remains too hypoplastic even after optimal palliation to tolerate biventricular repair with closure of the atrial septal defect. In these patients, nonpulsatile cavopulmonary (Glenn) anastomosis has traditionally facilitated biventricular repair. In 1989, Billingsley and associates reported the addition of a bidirectional cavopulmonary anastomosis to the definitive biventricular repair in patients with hypoplastic right ventricle, pulmonary atresia, and intact ventricular septum. The atrial septal defect was left open with an adjustable snare for later closure. We report five patients with hypoplastic right ventricle (mean diastolic volume 48.4%, mean stroke volume 40.2% of predicted value) who had the atrial septal defect closed at the time of the biventricular repair. Four patients, who had the bidirectional cavopulmonary anastomosis supplementing the biventricular repair, had no evidence of excessive right atrial or superior vena cava hypertension postoperatively. One patient, who had atypical tetralogy of Fallot with tricuspid stenosis, developed recurrent pericardial tamponade and marked hepatomegaly following conventional tetralogy repair with closure of the atrial septal defect. These complications were controlled with the addition of bidirectional cavopulmonary anastomosis 2 months later. Postoperative hemodynamic or Doppler studies in these patients revealed pulsatile flow in the entire pulmonary artery system, including the artery distal to the Glenn anastomosis. This modification of biventricular repair allows primary closure of the atrial septal defect and provides pulsatile arterial flow in the entire pulmonary artery, even when the right ventricle is significantly hypoplastic.

Fenestrated Fontan with delayed catheter closure. Effects of volume loading and baffle fenestration on cardiac index and oxygen delivery

BACKGROUND. The fenestrated Fontan operation has been applied to high-risk patients with univentricular hearts, resulting in improved survival. The purpose of this study was to determine the hemodynamic factors responsible for these improved results. METHODS AND RESULTS. We performed the fenestrated Fontan operation in 17 high-risk patients with univentricular hearts (median age, 3 years; age range, 1.2-25 years). High-risk characteristics were depressed ventricular function and/or hypertrophy (n = 12), atrioventricular valve insufficiency (n = 5), pulmonary artery distortion (n = 6), elevated pulmonary vascular resistance (> 2 units/m2) (n = 4), previously failed Fontan operation (n = 2), or associated Wolff-Parkinson-White syndrome (n = 1). Intraoperative hemodynamic measurements (n = 8) included cardiac index (by aortic flow probe), peripheral arterial O2 saturations, and left and right atrial pressures during inflow occlusion, followed by volume loading with open versus closed fenestration. Mean baffle fenestration was 3.5 mm (range, 2.7-5.0 mm). Multiple regression analysis (cardiac index versus atrial pressure) revealed cardiac index was greater with open than with closed fenestration (p < 0.001) during volume loading. Oxygen delivery (cardiac index multiplied by oxygen content) was also greater with open than with closed fenestration (p < 0.001). Survival was 100% with a mean follow-up of 10.4 months; pleural drainage was high in two patients. Subsequent transcatheter fenestration closure resulted in increased O2 saturation (87 +/- 1% to 96 +/- 0.3%, p < 0.05). CONCLUSIONS. The fenestrated Fontan operation improves survival in high-risk patients by increasing cardiac index and maintaining oxygen delivery, despite mild arterial O2 desaturation. Subsequent transcatheter fenestration closure can be performed after hemodynamic assessment.

Ventricular volume growth after cardiac transplantation in infants and children

BACKGROUND

Intermediate-term survival after pediatric cardiac transplantation continues to improve. However, little is known about cardiac function and especially ventricular growth in young patients after cardiac transplantation. The purpose of this study was to evaluate serially the hemodynamics, left ventricular (LV) volume, and ventricular function after cardiac transplantation in infants and children.

METHODS AND RESULTS

Indications for cardiac transplantation were dilated cardiomyopathy (eight patients), hypoplastic left heart syndrome (six patients), and postoperative structural congenital heart disease (three patients). The age at time of transplant ranged from 7 days to 15 years (median, 3.5 years). The mean follow-up was 30.3 months (range, 13-46 months). Serial annual cardiac catheterizations were performed 1 year (17), 2 years (15), and 3 years (seven) after transplant. Measurements included right and left heart pressures, cardiac index, and LV volume and ejection fraction (Lange). Cumulative results (expressed as mean +/- SD) were pulmonary artery pressure, 14.9 +/- 3.2 mm Hg; LV end-diastolic pressure, 7.7 +/- 2.6 mm Hg; cardiac index, 3.5 +/- 0.52 l/min.m-2; and pulmonary vascular resistance, 2.02 +/- 0.76 units/m2. LV end-diastolic volume increased as patients grew, so that left ventricular end-diastolic volume remained 90 +/- 14% of that predicted for body surface area. The ejection fraction was 99 +/- 6% of that predicted. There was no evidence of chronic rejection by endomyocardial biopsy. No accelerated coronary artery atherosclerosis was identified.

CONCLUSIONS

Serial studies in these young patients demonstrate normal hemodynamics and LV function after cardiac transplantation. Cardiac transplantation is associated with normal LV volume growth despite immunosuppression and denervation.

Anomalous origin of the left coronary artery. A twenty-year review of surgical management

Children with anomalous origin of the left coronary artery from the pulmonary artery are at risk for myocardial infarction and death. Surgical management of this condition in children has evolved significantly during the past 20 years. Between 1970 and 1990, a total of 20 of these patients underwent surgical intervention at two institutions. Age at operation ranged from 3 weeks to 11 years (mean, 26 months). Twelve patients had congestive heart failure, three were in cardiogenic shock, and two had cardiac murmurs. Operative techniques included ligation (n = 9), subclavian artery anastomosis (n = 5), aortic implantation (n = 3), internal mammary artery anastomosis (n = 1), intrapulmonary tunnel from aortopulmonary window to coronary artery (n = 1), and cardiac transplantation (n = 1). The three deaths in the series occurred at 3 weeks, at 2 months, and at 9 years after ligation. There have been no deaths after establishment of a two coronary artery system or after transplantation. Two of the five patients who had subclavian artery anastomosis to the anomalous coronary artery have severe anastomotic stenosis and collateralization. For patients with anomalous origin of the left coronary artery from the pulmonary artery, we recommend direct aortic implantation of the anomalous coronary artery at the time of diagnosis. Intrapulmonary tunnel from aortopulmonary window to coronary artery, or aorta-coronary bypass with internal mammary artery are recommended for children in whom aortic implantation is not anatomically feasible. Left coronary artery ligation is not indicated for these patients; those who have survived ligation should be considered for elective establishment of a two coronary artery system because of the risk of late death.

Ventricular septal defect with tricuspid pouch with and without transposition. Anatomic and surgical considerations

In a 10-year review, patients operated on for ventricular septal defect and tricuspid valve pouch were divided into two groups, because the effect of the tricuspid valve pouch is influenced by which ventricle has the higher pressure. Group I comprised patients with ventricular septal defect without transposition of the great arteries and group II, ventricular septal defect with transposition. In 72 of 392 group I patients, the septal tricuspid valve leaflet was incised to expose the edges of the hidden ventricular septal defect to accomplish proper anatomic repair. Forty-eight patients had a tricuspid valve pouch, the diagnosis being established by angiography, echocardiography, or at operation. Ages at operation ranged from 5 months to 22 years and the pulmonary-systemic flow ratio ranged from 1 to 3.4, with 16 being less than 1.5. In one patient the pouch produced a 40 mm Hg pressure gradient in the right ventricular outflow tract. At operation, through a transatrial approach, the tricuspid valve pouch was opened radially, the actual ventricular septal defect patched, and the tricuspid valve leaflet repaired. There were no deaths, no significant intraoperative or postoperative morbidity, and no tricuspid valve dysfunction. The average postoperative hospital stay was 4.8 days. In group II, six of 83 patients operated on for transposition with ventricular septal defect had significant left ventricular outflow tract obstruction from the tricuspid valve pouch. Five of six had a Mustard procedure, two requiring a left ventricular-pulmonary artery conduit, and in two of the six the ventricular septal defect was closed through the pulmonary artery. One patient had heart transplantation after a Mustard repair and tricuspid valve replacement. The sixth patient in group II had a successful arterial switch at 9 years of age, after the presence of left ventricular outflow tract obstruction was proved to be due to the pouch. The presence of a tricuspid valve pouch in group I may lead the surgeon to close false small openings produced by the pouch rather than the actual ventricular septal defect. Incising the pouch is safe and essential for proper exposure and secure closure of the true defect. In group II, the systemic right ventricular pressure can push the pouch into the left ventricular outflow tract, causing significant obstruction, and may contribute to tricuspid valve insufficiency after atrial baffle repair. Arterial switch is preferred because it returns the obstructive tricuspid valve pouch and abnormal tricuspid leaflet to the lower pressure pulmonic right ventricle.

Surgical management of the conal (supracristal) ventricular septal defect

Surgical management of the conal (supracristal) ventricular septal defect differs significantly from the management of the perimembranous (infracristal) ventricular septal defect. The absence of a portion of the conal septum can lead to prolapse of the right cusp of the aortic valve, which predisposes these patients to aortic insufficiency. Between January 1980 and December 1989, 36 children with conal ventricular septal defect underwent intracardiac repair. Diagnosis was by echocardiography, cardiac catheterization, and intraoperative exploration. Preoperative evaluation showed that 26 patients (72%) had aortic valve prolapse and 16 (44%) had aortic insufficiency. Pulmonary-to-systemic flow ratios ranged from 1:1 to 3.5:1 (mean 2.0:1.0). Ten patients (27%) were believed to have clinical congestive heart failure. Age at the time of operation ranged from 2 weeks to 18 years (mean 5.5 years). Operative exposure was through the pulmonary artery (26), aorta (4), right ventricle (3), or right atrium (3). Simultaneous aortic valve suspension for aortic insufficiency was performed in four patients. Operative survival was 100%. Follow-up is complete in all patients and ranges from 0.5 to 9 years (mean 4.3 years). All patients are in normal sinus rhythm. No residual ventricular septal defects have been identified. Twenty-three of 36 patients (64%) have no evidence of aortic insufficiency; 12 of 36 (33%) have trivial or mild aortic insufficiency. One patient with initial severe aortic insufficiency underwent repeat aortic valvuloplasty 3 years after ventricular septal defect closure and aortic valve suspension. No patients have required aortic valve replacement. Surgical management of the conal ventricular septal defect differs from that of the perimembranous ventricular septal defect in two critical aspects. The operative approach should be through the pulmonary artery. This allows the best exposure of the remaining conal septum and the pulmonary and aortic valve leaflets, facilitating closure of the defect without injury to the valves or conduction system. Conal ventricular septal defects should undergo early closure, regardless of shunt volume, to prevent progressive aortic insufficiency.

An alternative approach to the surgical management of physiologically corrected transposition with ventricular septal defect and pulmonary stenosis or atresia

A modified approach to the surgical management of corrected transposition of the great vessels with ventricular septal defect and pulmonary stenosis or atresia was used successfully in two patients. The procedure consisted of performing a venous switch operation, directing the blood flow from the morphologically left ventricle (right-sided chamber) into the aorta through the ventricular septal defect and inserting a valved conduit between the left-sided morphologically right ventricle and the pulmonary artery. This approach has several advantages when compared with the traditional surgical management, which consists of closure of the ventricular septal defect and a left ventricular (right-sided chamber) to pulmonary artery conduit. It uses the morphologically left ventricle as the systemic pumping chamber, thereby minimizing long-term ventricular failure. It allows closure of the defect from the right ventricular side of the septum, thus decreasing the prevalence of complete atrioventricular block. It also avoids use of the tricuspid valve as the systemic atrioventricular valve and therefore decreases the chance of postoperative valve regurgitation.

Balloon angioplasty--branch pulmonary artery stenosis: results from the Valvuloplasty and Angioplasty of Congenital Anomalies Registry

Balloon angioplasty for branch pulmonary artery stenosis was reported from 27 institutions to the Valvuloplasty and Angioplasty of Congenital Anomalies Registry. One hundred eighty-two procedures were performed in 156 patients ranging in age from 0.2 to 46.2 years (mean 7.7). Short-term angiographic appearance, hemodynamic results and immediate complications were recorded. Vessel dimension at the site of stenosis increased from 4.5 +/- 2.0 (mean +/- standard deviation) to 6.8 +/- 3.0 mm (p less than 0.001) with greater increases in vessel dimension at the site of stenosis if the balloon diameter was greater than 3 X the original dimension of the stenosis. There was no significant benefit related to age or prior surgical intervention. The mean peak systolic pressure gradient was reduced from 49 +/- 25 to 37 +/- 26 mm Hg (p less than 0.001) and pressure proximal to the stenosis decreased from 69 +/- 25 to 63 +/- 24 mm Hg (p less than 0.001). Complications occurred in 21 patients and included vessel rupture and death in 2 patients, vessel perforation or rupture with survival in 3, cardiac arrest and death in 1, paradoxical embolism and death in 1 and low output and death in 1. Balloon angioplasty for branch pulmonary artery stenosis increases vessel dimension at the site of stenosis, reduces systolic pressure gradient and to a minor degree, reduces proximal pressure. Long-term outcome and potential complications are as yet uncertain.

Relation between preoperative left ventricular muscle mass and outcome of the Fontan procedure in patients with tricuspid atresia

The relation between preoperative left ventricular muscle mass and clinical outcome of the Fontan procedure was evaluated retrospectively in 22 patients with tricuspid atresia who were selected for this physiologic surgical correction by conventional hemodynamic criteria. Patients were divided into two groups: group A (excellent or good outcome) and group B (poor outcome or death) based on the clinical course assessed up to 9.5 years postoperatively. Thirteen of 22 group A patients did not have prolonged, clinically significant, systemic venous hypertension and were not on long-term diuretic drug therapy. Nine of 22 group B patients either had clinically significant systemic venous hypertension, required long-term diuretic drug therapy or died (3 patients). Age at surgery, pulmonary arteriolar resistance, left ventricular ejection fraction, end-diastolic volume, end-diastolic pressure, systemic oxygen saturation and pulmonary to systemic blood flow ratio (Qp/Qs) were not statistically different between the two groups. Left ventricular muscle mass, both in group A patients (92 +/- 31 g/m2) and in group B patients (146 +/- 61 g/m2), was greater than the normal mean value (p less than 0.01 and p less than 0.001, respectively). Left ventricular muscle mass in group B was significantly greater than in group A (p less than 0.01). Furthermore, left ventricular muscle mass/end-diastolic volume (mass/volume) ratio, reflecting the extent of left ventricular hypertrophy relative to volume overload, was significantly greater in group B (1.1 +/- 0.28) than in group A (0.84 +/- 0.21) (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Transposition of the great arteries: a comparison of results of the mustard procedure versus the arterial switch

Sixty infants with transposition of the great arteries and intact ventricular septum underwent primary surgical correction in the first 3 months of life. Twenty-three patients had a Mustard procedure (group 1) and 37 patients, an arterial switch operation (group 2). The mean age at the time of repair was 42 +/- 31 days for group 1 and 8 +/- 6 days for group 2 (p less than 0.001). The mean weight at the time of repair was 3.6 +/- 0.7 kg for group 1 and 3.4 +/- 0.5 kg for group 2 (p = not significant). Operative mortality was 8.7% (2/23) in group 1 and 8.1% (3/37) in group 2 (p = not significant). The incidence of arrhythmias in the early postoperative period was 39% (9/23) in group 1 and 11% (4/37) in group 2 (p less than 0.01). All patients were followed a mean of 4.8 +/- 2.4 years in group 1 and 2.6 +/- 1.4 years in group 2 (p less than 0.001). Postoperative catheterization has been performed in 86% (18/21) of group 1 operative survivors and 50% (17/34) of group 2 operative survivors. Ejection fraction of the systemic ventricle was 79% +/- 15% of predicted normal in group 1 and 98% +/- 6% in group 2 (p less than 0.005). The incidence of late arrhythmias was 57% (12/21) in group 1 and 3% (1/34) in group 2 (p less than 0.001). There have been 2 late deaths in group 1 and 1 late death in group 2 (p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Direct tricuspid closure versus atrial partitioning in Fontan operation for complex lesions

Thirty-three patients with complex lesions undergoing the Fontan operation needed either direct tricuspid closure (group 1, 14 patients) or atrial partitioning (group 2, 19 patients). In group 1, the tricuspid patch was sutured to the annulus leaving the coronary sinus draining to the systemic venous atrium. In group 2, atrial partitioning was accomplished with either a Dacron or a polytetrafluoroethylene patch, leaving the coronary sinus draining to the pulmonary venous atrium. Intraoperative distention of the left side was used to check for residual defects. In group 1, complete heart block developed in 5 patients (36%) and patch disruption, in 4 patients (29%). There were 3 late deaths (21%), which were due to sudden death, sepsis caused by Candida, and liver failure. In group 2, no patient had heart block, and patch disruption developed in 1 patient (5%). There was 1 early death (5%) and 2 late deaths (11%), which were due to sepsis caused by Candida and renal failure. Our experience suggests that atrial partitioning is a better approach than direct tricuspid patch closure in patients with complex lesions undergoing the Fontan operation.

When should the hypoplastic right ventricle be used in a Fontan operation? An experimental and clinical correlation

Eight anesthetized dogs underwent closure of the tricuspid valve and a Fontan procedure, and the right ventricular cavity was reduced in stepwise fashion. There was an increase in right atrial pressure from 9.3 +/- 2.2 to 14.1 +/- 2.4 mm Hg (p less than 0.001), a decrease in pulmonary artery pulse pressure from 10.8 +/- 2.2 to 6.8 +/- 2.2 mm Hg (p less than 0.01), and a decrease in cardiac index from 2.7 +/- 0.3 to 2.2 +/- 0.2 L/min/m2 (p less than 0.001) when the ventricular size was dropped from 50% to 25% of normal. The difference between mean pulmonary artery pressure and mean right atrial pressure, which reflects the positive stroke work index of the ventricle, disappeared once the right ventricular cavity was reduced to 25% of normal (15.0 +/- 6.1 versus 14.1 +/- 2.4 mm Hg; p = not significant). Experimental results were correlated with postoperative catheterization data from 19 patients with tricuspid atresia who had the Fontan operation. Mean right atrial pressure was 18 +/- 4.6 mm Hg and cardiac index was 2.35 +/- 0.65 L/min/m2 in patients with a direct atrium-pulmonary artery anastomosis or an atrioventricular anastomosis with a right ventricular cavity less than 30% of normal versus 13 +/- 3.2 mm Hg and 3.42 +/- 0.46 L/min/m2 for those with an atrioventricular connection and a right ventricular cavity greater than 30% of normal (p less than 0.05 and p less than 0.02, respectively). The right ventricle enlarged from 27% +/- 6% of normal preoperatively to 35% +/- 10% of normal on follow-up (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Transposition of the great arteries with intact ventricular septum. Arterial switch in the first month of life

Twenty-three infants with simple transposition of the great arteries and intact ventricular septum were operated on from October 1983 to October 1986. The age at operation in 22 infants ranged from 2 to 21 days and in one was 35 days (mean 9.82 +/- 6.86 days). The infants were evaluated with cardiac catheterization at 1 to 27 days of age. Twenty-two infants had balloon atrial septostomy, and 22 received prostaglandin E1 infusion. The left ventricular diastolic wall thickness, assessed by M-mode echocardiograms, varied between 2.8 and 4 mm. There were two hospital deaths in this group of 23 infants (mortality 8.6%), and there were no late deaths. All surviving patients are doing well clinically. One patient had asymptomatic nonsustained ventricular tachycardia necessitating phenytoin. Postoperative echocardiographic assessment performed on 15 patients at 0.93 +/- 0.61 years of age and cardiac catheterization and angiographic studies on seven patients at 1.07 +/- 0.13 years after operation revealed excellent ventricular performance, good semilunar valve function, and mild gradient at the right ventricular outflow with a mean right ventricular pressure of 37.4 +/- 4.1 torr.

Surgical management of patients with interrupted aortic arch and severe subaortic stenosis

Ten patients underwent palliative surgery for interrupted aortic arch and severe subaortic obstruction due to posterior displacement of the conal septum. Their ages ranged between 4 and 28 days (mean, 11.0 +/- 7.7 days) and their weights, between 2.1 and 4.2 kg (mean, 2.85 +/- 0.6 kg). Preoperative echocardiography and cardiac catheterization were performed on all patients. The ratios of the left ventricular outflow tract diameters and the ascending aortic diameters to the descending aortic diameters were 0.56 +/- 0.03 and 0.56 +/- 0.06, respectively, compared with 0.81 +/- 0.12 and 0.95 +/- 0.17, respectively, in 20 patients with interrupted aortic arch but without obstruction (p less than 0.001). Four of the 10 patients underwent pulmonary artery banding and insertion of a bypass graft between the ascending and the descending aorta. All 4 died of low cardiac output soon after operation (100% operative mortality). The remaining 6 patients underwent banding and insertion of a graft between the main pulmonary artery proximal to the band, and the descending aorta. All of these patients survived, and all except 1 are doing well 3 months to 4 years postoperatively. The use of a pulmonary artery-descending aorta conduit and of distal pulmonary artery banding provides good palliation for patients with interrupted aortic arch and major subaortic stenosis.

Tetralogy of Fallot with absent ductus arteriosus and absent collateral pulmonary circulation: diagnostic and surgical implications during the neonatal period

A newborn infant with tetralogy of Fallot and presumed agenesis of the ductus arteriosus presented without the expected associated pulmonic regurgitation and aneurysmal pulmonary arteries. The presumption of agenesis of the ductus arteriosus was made because there was no reduction in cyanosis following prostaglandin E1 treatment and no remnant of ductus arteriosus could be demonstrated by angiography at 19 h of age. The fetal hemodynamics inferred in this infant are discussed with reference to the absence of aneurysmal pulmonary arteries. Closed transventricular pulmonary valvulotomy is recommended as emergency palliation for symptomatic newborns with this variant of tetralogy of Fallot because further reduction of pulmonary vascular bed, even temporarily, as in unilateral pulmonary artery cross-clamping for systemic-pulmonary anastomosis, may not be tolerated without the use of cardiopulmonary bypass.

Arterial switch in simple and complex transposition of the great arteries

Arterial switch for repair of transposition of the great arteries was performed on 53 patients since October 1983. These patients were divided into three groups: group I, 25 infants with an intact ventricular septum who had primary repair in the first month of life (2 to 34 days of age, mean 9.7 +/- 6.6); group II, 13 patients with an intact ventricular septum who had anatomic repair after a preliminary procedure (pulmonary artery banding in 13, shunt in 10, atrial septectomy in 1); and group III, 15 infants with transposition of the great arteries and ventricular septal defect. In group III, six patients had Taussig-Bing abnormality, nine had previous pulmonary artery banding, three had coarctation of the aorta repaired earlier in life, and four were less than 2 weeks old. Overall early mortality was 9.4% (5/53: group I 8%, group II 7.6%, group III 13.3%). Two late deaths occurred in group II 10 and 12 weeks postoperatively after infection and high fever. A third late death 18 weeks postoperatively was due to aspiration in an infant with Goldenhar's syndrome. Mortality and morbidity decreased significantly after an initial learning period (no deaths from July 1985 to March 1987 overall, and none in the last 15 infants operated on in group I). The surviving 45 patients are doing well. All have normal sinus rhythm. Two had transient asymptomatic arrhythmias. Left and right ventricular function assessed by echocardiogram and postoperative cardiac catheterization were within normal ranges in all but two patients, one with pulmonary artery stenosis and one (Taussig-Bing abnormality with two large ventricular septal defects) with severe pulmonary vascular disease (9.6 units) observed before anatomic repair. The right ventricular pressure at catheterization ranged from 27 to 42 mm Hg in 12 patients and was 55 mm Hg in two. There was no aortic stenosis. Aortic insufficiency was trivial in three patients and mild in one. We conclude that excellent results can be obtained with arterial switch for transposition of the great arteries with or without ventricular septal defect, especially in neonates.

Recognition of coarctation of the aorta. A continuing challenge for the primary care physician

Coarctation of the aorta (CoA) in its classic form presents with characteristic and distinctive physical findings. However, in our survey less than one third of 106 consecutive patients in whom CoA was ultimately diagnosed had the correct diagnosis made by the referring physician. Our survey suggests that in asymptomatic infants and children, an incomplete physical examination explains the diagnostic failure. However, in infants presenting with heart failure, the diagnostic signs of CoA may be obscured and more difficult to recognize even when specifically sought. This survey reaffirms the need for specific physical examination techniques in all infants and children to facilitate early recognition of CoA; these include the palpation of pulses and proper measurement of blood pressure.

Valve replacement in children: guidelines for selection of prosthesis and timing of surgical intervention

One hundred fifty-nine patients ranging from 3 months to 18 years old (mean, 8.1 +/- 3.7 years) underwent 162 primary valve implantations. A porcine valve was used in 104 patients, a St. Jude Medical valve in 40, and a Björk-Shiley valve in 18. The valve replaced was the aortic in 25 patients, the mitral (systemic atrioventricular [AV] valve) in 43, the pulmonary in 71, and the tricuspid (pulmonary AV valve) in 23. Hospital mortality was 6%. Patients with a Björk-Shiley valve received warfarin sodium anticoagulation, and those with a St. Jude Medical valve were given salicylates and dipyridamole. Follow-up is available on all patients 0.6 to 12 years postoperatively (mean, 6.3 +/- 2.6 years). New York Heart Association Functional Class improved in 62% and remained unchanged in 38% of the patients. Thromboembolic complications occurred in only 8 (57%) of 14 patients with a St. Jude Medical valve in the right (pulmonary) side and in 3 (12%) of 26 with the valve in the left (systemic) side of the circulation. Bacterial endocarditis developed in 3 patients, all with porcine valves. Early valve replacement, less than 2 years after detection of hemodynamic deterioration, resulted in improvement in the ventricular ejection fraction in 25 of 29 patients (from 81 +/- 14% to 90 +/- 12% of normal; p less than 0.05). In contrast, the ejection fraction remained abnormal in all 22 patients with delayed valve insertion (more than 2 years) (81 +/- 16% of normal preoperatively and 80 +/- 10% of normal following operation; p = not significant).

Preparation of the left ventricle for anatomical correction in patients with simple transposition of the great arteries. Surgical guidelines

Pulmonary artery banding in combination with an aortopulmonary shunt was performed on 16 patients with simple transposition of the great arteries to prepare the left ventricle for anatomical correction. Three groups were identified after operation: Group I (four patients) had increased pulmonary blood flow and tight pulmonary artery banding; Group II (four patients) had increased pulmonary blood flow and moderate pulmonary artery banding; Group III (eight patients) had normal pulmonary blood flow and moderate pulmonary artery banding. Postoperative low cardiac output was present in all patients in Group I, whereas mild heart failure was present in two patients in Group II and in two in Group III. There was one hospital death (6%). The follow-up period was 125 patient-months. Left ventricular systolic pressure rose from 63 +/- 11 torr before the operation to 101 +/- 35 torr after the procedure in Group I (p less than 0.05), from 59 +/- 10 to 93 +/- 33 torr in Group II (p less than 0.05), and from 55 +/- 10 to 84 +/- 16 torr in Group III (p less than 0.005). The increase in left ventricular muscle mass was from 44 +/- 2 gm/m2 preoperatively to 108 +/- 12 gm/m2 after operation in Group I (p less than 0.01), from 43 +/- 3 to 93 +/- 8 gm/m2 in Group II (p less than 0.02), and from 46 +/- 3 to 55 +/- 14 gm/m2 in Group III (p = no statistically significant difference). The postoperative change in left ventricular end-diastolic volume was from 100% +/- 17% to 133% +/- 23% of normal in Groups I and II (p less than 0.05) and from 123% +/- 29% to 107% +/- 36% of normal in Group III (p = no statistically significant difference). In preparing the left ventricle for anatomical correction, avoidance of severe pulmonary artery banding decreases the incidence of postoperative myocardial dysfunction, a moderate degree of volume overload and pulmonary artery banding provides the most effective stimulus for ventricular growth, and a small to moderate atrial septal defect is advantageous because it ensures the volume preload necessary for the development of the left ventricle.

Development of neo-coarctation in patients with transposed great arteries and hypoplastic aortic arch after Lecompte modification of anatomical correction

We report on three patients with kinking in the proximal aortic arch that developed after Lecompte modification of the arterial switch operation. Two patients had a previous subclavian patch repair of coarctation of the aorta and had an associated hypoplasia of the transverse aortic arch, and one patient had hemodynamically mild coarctation at the anatomical repair. A severe pressure gradient across the kinked area ("neo-coarctation") necessitating reoperation developed in one patient. The acute arch angulation appears to be due to an excessive posterior displacement of the ascending aorta by the anterior relocation of either the right or left main pulmonary artery branch from underneath the aortic arch. A foreshortened and frequently hypoplastic transverse aortic arch, a common association with coarctation of the aorta, appears to be especially vulnerable to the development of "neo-coarctation" after the Lecompte modification of the anatomical repair of transposed great arteries.

Surgical management of infants with complex cardiac anomalies associated with reduced pulmonary blood flow and total anomalous pulmonary venous drainage

Eight infants with complex cardiac anomalies and pulmonary stenosis or atresia were noted to have obstructed total anomalous pulmonary venous drainage (TAPVD) either at the initial cardiac catheterization (Group 1; n = 2) or after creation of systemic-pulmonary artery shunts (Group 2; n = 6). The 2 patients in Group 1 underwent early repair of TAPVD (1 at 7 days, the other at 1 1/2 months of age) before any subsequent operation and are now doing well at 18 months of age. The 6 patients in Group 2 underwent repeat cardiac catheterization because of persistent severe cyanosis with faint or absent continuous murmur and were found to have patent shunts and obstructed TAPVD (1 mild, 5 severe). One patient who underwent repair of TAPVD at 2 1/2 months of age survived and is well at 2 years of age, whereas 4 patients who underwent repair at an average age of 6 months (age range, 3-16 months) subsequently died. The sixth patient, who did not undergo repair, remained severely cyanotic with hypoplastic pulmonary arteries in spite of repeated shunts. We feel that increased awareness of the possible association of TAPVD and reduced pulmonary blood flow in infants with complex cardiac defects, in combination with echocardiography, oxygen saturation studies, and angiography with prostaglandin E1 challenge, should lead to early diagnosis, avoidance of unnecessary systemic-pulmonary artery shunts, and increased survival rates in these infants.

Factors that exaggerate the deleterious effects of pulmonary insufficiency on the right ventricle after tetralogy repair. Surgical implications

Postoperative cardiac catheterization data of 74 patients with pulmonary insufficiency after tetralogy repair were analyzed. Two groups were identified: Group A, 26 patients with normal right ventricular function (ejection fraction 95% +/- 5.5%, end-systolic volume 110% +/- 17% of predicted normal) and Group B, 48 patients with right ventricular dysfunction (ejection fraction 80% +/- 18% [p less than 0.001], and end-systolic volume 218% +/- 75% of predicted normal [p less than 0.001]). There was no significant difference between the two groups with respect to frequency of previous palliative procedures, age at operative repair, operative techniques, methods of myocardial protection, and follow-up period. Right ventricular dysfunction in Group B was associated with significant distal pulmonary stenosis (right ventricle-pulmonary artery pressure gradient 28 +/- 13 torr in Group A versus 55 +/- 20 torr in Group B, p less than 0.001), moderate pulmonary regurgitation (regurgitant fraction 18% +/- 11% in Group A versus 32% +/- 10% in Group B, p less than 0.001), and large transannular outflow patch (ratio of patch diameter to descending aorta diameter 1.31 +/- 0.16 in Group A versus 2.50 +/- 0.28 in Group B, p less than 0.001). Pulmonary valve insertion was performed in 42 patients in Group B. Eighteen had subsequent cardiac catheterization. Right ventricular function recovered completely (end-systolic volume 122% +/- 24%, and ejection fraction 92% +/- 7% of predicted) in five of six patients (83%) who had valve insertion within the first 2 years after tetralogy repair. In contrast, right ventricular function remained abnormal in all 12 patients who had valve insertion later than 2 years after tetralogy repair (p less than 0.05). Patients with residual pulmonary stenosis and/or a large transannular outflow patch are at risk for the development of right ventricular dysfunction from pulmonary insufficiency after tetralogy repair. Early correction of these residual lesions and control of pulmonary insufficiency may prevent long-term deterioration in right ventricular function.

Experience with St. Jude Medical valve prosthesis in children. A word of caution regarding right-sided placement

Thirty-six children aged 6 months to 18 years, underwent insertion of 37 St. Jude Medical cardiac prostheses. In 20, the valve was placed in the aortic or mitral position, and in 16 in the pulmonary or tricuspid position. There was one (2.8%) hospital death. All patients received maintenance doses of salicylates and dipyridamole after the operation. Follow-up data are available for all patients for 12 to 24 postoperative months. There was no incidence of valve dysfunction or thromboembolic complication in any of the 20 patients with valves in the systemic (left) side of the circulation, and all manifested improvement in their functional class. In contrast, six (37%) of the 16 patients with valves in the pulmonary (right) side of the circulation developed dysfunction of the prosthesis 1 to 6 months after insertion. Prosthesis failure was associated with fibrous tissue growing into the struts, leading to leaflet immobilization. At 2 years, the actuarial functional life was 100% for mitral and aortic valves and 70% for pulmonary and tricuspid valves. The data illustrate the excellent hemodynamic function of the St. Jude Medical valve in children. The absence of thromboembolic complications warrant continued implantation of the prosthesis in the left side without warfarin anticoagulation therapy, but the high incidence of valve dysfunction in the pulmonary position does not justify its continued use in the right side.

Fontan type operation for complex lesions. Surgical considerations to improve survival

Twenty-five of 49 patients who underwent a Fontan type operation had complex lesions other than tricuspid atresia with ventriculoarterial concordance. Three patients had significant subaortic stenosis. Thirty-four palliative operations, including nine Glenn shunts, were performed before the Fontan operation. Direct atriopulmonary anastomosis was performed in 21 patients. In four, valved conduits were used. Twelve patients had right atrioventricular valve patch closure (three had running and nine had interrupted suture technique). On the basis of the presence of increased or decreased pulmonary blood flow before any surgical intervention, patients were divided into Group 1 (previous pulmonary artery banding, N = 8) and Group II (pulmonic stenosis, N = 17). Postoperatively, in Group I, 87% had significant effusions, mean right atrial pressure was higher (20.6 +/- 6.5 torr), and hospital stay longer (31 days). In Group II, 40% had significant effusions, mean right atrial pressure was lower (16.5 +/- 4.3 torr), and hospital stay shorter (15 days). Significant atrioventricular valve patch disruption occurred in three patients (two had running suture technique), and conduit occlusion occurred in two. Four patients (three with subaortic stenosis and pulmonary artery banding) without an established Glenn shunt required Fontan takedown for persistent low cardiac output, two of whom died (2/25 or 8%). There were three late deaths (3/23 or 13%). Nineteen of 20 surviving patients observed from 2 months to 6 years are doing well. We believe that early Fontan takedown in patients with persistent low cardiac output, interrupted suture technique for atrioventricular valve closure, avoidance of valved conduits, and a preliminary Glenn shunt in patients with pulmonary artery banding and/or subaortic stenosis can further improve the results with the Fontan operation for complex lesions.

Persistent low cardiac output after the Fontan operation. Should takedown be considered?

Four of 44 patients who had undergone the Fontan operation had persistent low cardiac output necessitating takedown of the shunt 6 to 65 hours (average 23 hours) postoperatively. All four were in a group of 22 patients with complex lesions other than tricuspid atresia with ventriculoarterial concordance. The development of postoperative right atrial hypertension (average 24 torr), hepatomegaly, marked ascites, and decreasing lung compliance led to severe systemic hypotension with systolic arterial pressure ranging from 55 to 82 torr (average 68 torr), persistent metabolic acidosis, and oliguria despite massive colloid and crystalloid infusions (11,000 ml/m2/24 hr) and inotropic support. At reoperation the atriopulmonary anastomosis, which was found to be wide open, was taken down and an atrial septal defect was created in all patients. Three patients were left with a Glenn shunt and an aortopulmonary shunt to the left lung. One patient had bilateral aortopulmonary shunts. Two patients who survived reoperation had immediate postoperative improvement in systolic arterial and mean right atrial pressure (average 100 torr and 11.5 torr, respectively). Both are well 5 months and 4 years later. Repeat Fontan operation remains a possibility with acceptable risks because of the presence of the Glenn shunt in both patients. We believe that takedown should be considered in patients with persistent low cardiac output after the Fontan operation.

Effects of elevated coronary sinus pressure on left ventricular function after the Fontan operation. An experimental and clinical correlation

An experimental model was devised to evaluate the effects of elevated coronary sinus pressure on left ventricular performance. Thirteen mongrel dogs were used. The coronary sinus was cannulated and its entire blood flow diverted into a reservoir. The pressure in the coronary sinus was increased from 5 to 25 torr by elevating the drainage reservoir in a stepwise fashion. Cardiac index, coronary arteriovenous difference, rate of rise of left ventricular pressure, left ventricular systolic time intervals, and coronary blood flow were measured. When the coronary sinus pressure reached 15 torr, there was a significant decrease in cardiac index (3.60 +/- 0.5 to 2.70 +/- 0.6 L/min/m2, p less than 0.001), coronary blood flow (13.7 +/- 3.1 to 7.0 +/- 2.1 ml/min, p less than 0.001), rate of rise of left ventricular pressure (1,567 +/- 275 to 1,331 +/- 314, p less than 0.05), and an increase in coronary arteriovenous difference (62.8% +/- 9.3% to 70.5% +/- 5.4% saturation, p less than 0.03). These experimental results were correlated with postoperative catheterization findings in 24 patients with the Fontan procedure. Patients with a mean right atrial pressure less than 15 torr had a left ventricular ejection fraction of 93% +/- 6% of predicted, whereas patients with a right atrial pressure of 15 torr or more had a left ventricular ejection fraction of 75% +/- 13% of predicted (p less than 0.001). These experimental and clinical data strongly suggest that elevated coronary sinus pressure has deleterious effects on ventricular function after the Fontan procedure. Modifications of the procedure, such as using the rudimentary right ventricle when feasible or diverting coronary sinus flow to the pulmonary venous atrium, might decrease coronary sinus hypertension and improve long-term results.

The Damus-Stansel-Kaye procedure. Should the aortic valve or subaortic valve region be closed?

Two patients (one with transposition of the great arteries and another with Taussig-Bing anomaly) underwent the Damus-Stansel-Kaye procedure (Group I). Significant aortic valve insufficiency developed postoperatively in both patients. In contrast, seven patients with a univentricular heart and subaortic stenosis from a variety of reasons underwent creation of an aortopulmonary window (Group II), a procedure very similar to the proximal main pulmonary artery-aortic root anastomosis of the Damus-Stansel-Kaye procedure. Aortic valve insufficiency had not developed after up to 7 years of follow-up in this group (average 43 months). Postoperative angiograms suggest that aortic valve incompetence in Group I may have been caused by prolapse of the aortic valve. The valvular structures are subjected to high systolic pressures and face a dilated, low-pressure right ventricle. Aortic root distortion may have contributed, as well. In Group II patients, the aortic valve structures face a small, thick-walled chamber. The orientation of the aortic valve vis-a-vis the right ventricle changed postoperatively in Group I but not in Group II patients. Our experience suggests that the aortic valve or subaortic valve region should be closed at the initial repair in patients with low pulmonary vascular resistance who are undergoing the Damus-Stansel-Kaye procedure, to minimize the need for reoperation for aortic valve insufficiency.

Long-term results of porcine valve insertion for pulmonary regurgitation following repair of tetralogy of Fallot

Between January 1975 and January 1985, 49 patients, aged 2 to 20 years, underwent porcine valve insertion for control of pulmonary regurgitation following repair of tetralogy of Fallot. In 9 patients the valve was placed at the time of the repair; in the remaining 40, valve insertion was performed 2 to 5 years postoperatively. The primary indications for valve implantation included progressive cardiomegaly and evidence of right ventricular (RV) dilatation or dysfunction. Operative technique emphasized ample enlargement of the RV outflow tract and main pulmonary artery to allow for insertion of a large valve and prevention of turbulence or stenosis. There was 1 hospital death (2%). Follow-up is available on remaining patients 1 to 10 years postoperatively. Considerable prosthetic valvar stenosis or regurgitation occurred in 7 patients (14%) 3 to 8 years following insertion, including one after subacute bacterial endocarditis. The complication-free actuarial life was 82%, and the functional actuarial life was 84% at 10 years for the prosthesis. The data suggest that the porcine valve has a good long-term durability when inserted in the pulmonary position in pediatric patients.

Surgical approach to severely symptomatic newborn infants with tetralogy of Fallot and absent pulmonary valve

The surgical management of severely symptomatic newborn infants with tetralogy of Fallot and absent pulmonary valve has been controversial, and the results of a variety of operative approaches have not been satisfactory. We report on a technique for the treatment of these patients, which consists of (1) ligation of the main pulmonary artery to eliminate pulmonary regurgitation, excessive right ventricular stroke output, and secondary pulmonary artery dilation and airway obstruction and (2) insertion of a subclavian-pulmonary artery polytetrafluoroethylene shunt to provide pulmonary blood flow. The procedure was used in four neonates. Two patients operated on at 2 and 3 days of age are doing well 15 and 19 months postoperatively. The other two, operated on at 3 and 4 weeks of age after unsuccessful prolonged medical treatment and positive-pressure ventilation, failed to show long-term improvement and died of sepsis and respiratory failure 3 and 5 months after operation. This experience, though limited, suggests that early surgical intervention to control pulmonary regurgitation prevents progressive pulmonary artery dilatation and secondary bronchial compression, decreases the need for prolonged preoperative and postoperative ventilation, and improves the outcome of these critically ill neonates.

Functional aortic valve atresia in transposition of the great arteries

The criterion for the diagnosis of functional atresia of a patient semilunar valve is met when the pressure in a ventricle remains lower than that in the related great artery throughout systole so that no forward flow can occur. Functional pulmonary valve atresia has been well recognized in infants with normally related great arteries and massive tricuspid valve incompetence. The cardiac physiology and anatomy of an infant with transposed great arteries and functional aortic valve atresia is reported for the first time. The peak systolic pressure in the right ventricle was 30 mm Hg and in the aorta 64 mm Hg. The causes for right ventricular incompetence were abnormalities of the tricuspid valve and hypoplasia of the ventricular free wall. Three other cases with similar ventricular anatomy and physiology but with anatomic atresia of the aortic valve are reviewed. The possibility that under these physiologic circumstances during fetal life functional atresia develops first, and that anatomic fusion of idle semilunar cusps develops as a secondary phenomenon, is discussed.

Modified Blalock-Taussig shunt in newborn infants

The modified Blalock-Taussig shunt, interposing an expanded polytetrafluoroethylene graft between the subclavian and pulmonary arteries, was performed in 30 neonates with a mean age of 8.8 days and a mean weight of 3.14 kg. Underlying lesions included severe tetralogy of Fallot or its variant (N = 10), transposition complex (with pulmonary stenosis or atresia) (N = 6), single ventricle equivalents (with pulmonary atresia or stenosis) (N = 9), and pulmonary atresia with intact ventricular septum (N = 5). The mean preoperative arterial oxygen tension prior to prostaglandin E1 therapy was 29.5 torr. The shunt was performed through a right thoracotomy in 18 patients, through a left thoracotomy in nine, and through a median sternotomy in three. A 5 mm graft was used in 21 patients and a 6 mm graft in nine patients. The mean postoperative arterial oxygen tension was 64.1 torr (p less than 0.001). The incidence of early shunt occlusion was 3.3% and the hospital mortality was 3.3%. Actuarial functional life of the shunt (no death or reoperation related to shunt failure) was 91% at 3 years' follow-up. Nine patients were recatheterized. There was no distortion of the pulmonary artery. The ratios of the diameter of the right pulmonary artery and pulmonary valve anulus to that of the descending aorta increased after the operation by 50% (p less than 0.001) and 52% (p less than 0.05), respectively. Our experience indicates that the modified Blalock-Taussig shunt has an excellent function, offers several technical advantages, and lacks most of the drawbacks of other systemic-pulmonary artery shunts. It may be the shunt of choice in patients less than 1 month of age.

Surgical management of occluded conduits after the Fontan operation in patients with Glenn shunts

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.

The surgical management of left ventricular outflow tract obstruction due to tricuspid valve pouch in complete transposition of the great arteries

Subpulmonary stenosis in transposition of the great arteries, resulting from a tricuspid valve pouch bulging into the left ventricular outflow tract through a ventricular septal defect, can be missed at the time of operation in the flaccid, nonbeating heart unless preoperative diagnosis has been established. In our experience, six patients were found to have this lesion. In four patients the tricuspid valve pouch was recognized preoperatively. At operation, retraction of the tricuspid valve pouch into the right ventricle, patch closure of the ventricular septal defect, and a Mustard procedure were performed in three patients; the fourth is awaiting correction following initial palliation with a subclavian-pulmonary shunt. In the other two, the ventricular septal defect was partially or completely obliterated by a tricuspid valve pouch that was missed preoperatively and during exploration at the time of the Mustard procedure. Residual left ventricular outflow tract obstruction was subsequently corrected with a left ventricle-pulmonary artery valved conduit. Echocardiographic and angiocardiographic examinations offer helpful signs for the diagnosis of tricuspid valve pouch. Transatrial retraction of the redundant tricuspid valve tissue into the right ventricle, patch closure of the ventricular septal defect, and Mustard operation are the procedures of choice. A left ventricle-pulmonary artery valved conduit may be required for residual unresectable left ventricular outflow tract obstruction.

Transient neonatal tricuspid regurgitation: possible relation with premature closure of the ductus arteriosus

Normal fetal circulation requires patency of the ductus arteriosus. Prenatal ductal closure causes profound circulatory changes, such as massive tricuspid regurgitation. After delivery, the clinical picture of these severely distressed cyanotic newborns usually improves rapidly as the circulation is no longer dependent on ductal patency after onset of respiration. This case report deals with a newborn infant with severe tricuspid regurgitation and a large atrial right to left shunt who was treated with prostaglandin E1 infusion at 12 hours of age and in whom cardiac angiography revealed no evidence of either patent or functionally closed ductus arteriosus and no anatomic cardiac abnormalities at 30 hours of age. On the basis of physiologic and morphologic observations in this infant, the possible role of premature ductal narrowing or closure in the pathogenesis of transient neonatal tricuspid regurgitation is discussed. It is recommended that documentation of ductal presence or absence should become part of the diagnostic evaluation of newborns with transient tricuspid regurgitation.

Masked subaortic stenosis in ostium primum atrial septal defect: recognition and treatment

Five patients with ostium primum atrial septal defect (ASD) and a cleft mitral valve had no hemodynamic evidence of left ventricular (LV) outflow tract obstruction on preoperative cardiac catheterization. After surgical closure of the ASD and repair of the mitral cleft, all 5 patients manifested subaortic stenosis with pressure gradients ranging from 10 to 120 mm Hg. Postoperative LV angiograms revealed systolic narrowing of the outflow tract, and the same outflow tract dynamics were recognized on reviewing the preoperative angiograms and echocardiograms. Persistence or exaggeration of the characteristic diastolic "goose-neck" deformity during LV systole in atrioventricular canal defects is diagnostic of a potential or actual subaortic obstruction. This diagnostic sign is also readily recognizable by 2-dimensional echocardiography, and when present, the surgeon should be alerted to explore the LV outflow tract because the outflow tract anatomy is not readily apparent at operation aimed solely at closing the ASD and repairing the cleft mitral valve.