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Seventy three infants who underwent neonatal anatomical correction for transposition of the great arteries with or without a ventricular septal defect were reviewed for evidence of conduction and rhythm abnormalities on preoperative and postoperative 12 lead electrocardiograms and during 24 hour Holter monitoring. There was a partial right bundle branch block pattern in 47% (29/62) of all patients and in 60% (24/40) of those with simple transposition. Complete right bundle branch block was noted in 21% including 5% with simple transposition. Holter monitoring showed sinus rhythm in all patients except three: one had episodes of supraventricular tachycardia, another an intermittent second degree heart block, and a third a complete heart block. Atrial extrasystoles were noted in 47% (29/62) of patients but were frequent in only three patients. Occasional unifocal ventricular extrasystoles were encountered in 37% (23/62) of patients and were frequent in a further 3% (2/62). Only one patient (2%) developed multifocal ventricular extrasystoles. The frequency of important cardiac arrhythmias after neonatal anatomical correction of transposition of the great arteries was 5%, significantly less than that reported after atrial inflow diversion for the same malformation. [ABSTRACT FROM PUBLISHER]

Radionuclide studies were performed to determine pulmonary blood flow in six children who had undergone surgery for pulmonary atresia, ventricular septal defect, and hypoplastic pulmonary arteries with or without major aortopulmonary collateral arteries. Lung blood flow was assessed from both particle perfusion lung scans and the pulmonary and systemic phase of a radionuclide dynamic flow study. Five patients had perfusion defects identified on the particle perfusion lung scan. In three of these, abnormal areas were perfused only during the systemic phase of the flow study, a combination of findings that indicate the presence of perfusion by collateral arteries. In one patient no systemic perfusion was noted and in one an initial particle perfusion study indicated the presence of a lung segment perfused by a collateral artery. In this last patient the particle perfusion scan after total correction showed a reduction in the size of the lung perfusion defect and no evidence of lung perfusion during the systemic phase of the flow study. The particle perfusion lung scan in the sixth patient showed pronounced asymmetry in blood flow to the lungs with no segmental perfusion defect on the particle perfusion scan and no abnormalities on the systemic flow study. It is concluded that radionuclide lung perfusion and flow studies provide useful information on lung perfusion and merit further evaluation to define their role in the management of these patients. [ABSTRACT FROM PUBLISHER]

Objective: The results of our modification of the stage I Norwood procedure, in which we use only autologous tissue to reconstruct the aortic arch, were reviewed. A high-flow, low-pressure cardiopulmonary bypass protocol (with phenoxybenzamine), before and after a period of deep hypothermic circulatory arrest, was used., Methods: Between 1993 and 1999, 59 patients, aged 1 to 353 days (median 4 days) and weighing 1.7 to 6.8 kg (median 3.2 kg), underwent a modified Norwood procedure. The ascending aortic diameter ranged from 1.5 to 8 mm (median 3 mm). The modified Blalock-Taussig shunt was 3 mm in 21 patients (36%) and 3.5 mm or larger in 38 patients (64%)., Results: Deep hypothermic circulatory arrest and cardiopulmonary bypass times ranged from 15 to 64 minutes (median 37 minutes) and 44 to 144 minutes (median 88 minutes), respectively. Early postoperative survival was 83%. By univariate analysis, early mortality was associated with an ascending aortic diameter of 2.5 mm or less (P =.01). Weight, circulatory arrest and bypass times, diagnosis (hypoplastic left heart syndrome vs variant), shunt size, and date of the procedure did not affect survival. For a median follow-up period of 37 months (range 4-63 months), 42 (61%) patients underwent bidirectional cavopulmonary shunts, 10 (17%) had Fontan operations, and 1 patient underwent transplantation after a bidirectional cavopulmonary shunt. Eight patients subsequently died, for a 1-year actuarial survival of 72% (95% confidence interval: 60%-84%). Neoaortic arch obstruction was corrected in 3 patients (5%)., Conclusions: At intermediate-term follow-up, our modification of the Norwood procedure together with our perioperative strategies has resulted in acceptable outcomes with a low incidence of neoaortic arch obstruction. Patients with a small ascending aortic diameter have emerged as a high-risk group, but a recent technical modification may improve the outlook for these patients.

Background: N-methyl-d-aspartate (NMDA) receptor antagonists are neuroprotective in animal models of cerebral ischemia, but adverse cardiovascular and neurobehavioral effects have precluded their clinical use. The authors present the neuroprotective, anesthetic, and cardiovascular effects of a novel NMDA antagonist, CNS 5161A., Methods: Lambs, 4.0-6.5 kg, were anesthetized with isoflurane, intubated, and ventilated and had thermodilution catheters placed in the pulmonary artery and 20-g catheters placed in the femoral artery. The minimum alveolar concentration (MAC) of isoflurane was determined using the "bracketing technique." CNS 5161A was given as a bolus and then as an infusion at three doses. Cardiovascular measurements were determined every 15 min. Other lambs (n = 25) were subjected to cardiopulmonary bypass (CPB) with hypothermic circulatory arrest (HCA) for 120 min. Eighteen received CNS 5161A, and seven received saline vehicle. One hour after CPB, brains were perfusion-fixed and removed for in situ hybridization and immunohistochemistry analysis in half of the animals. The other half survived 48 h before their brains were examined for neuronal degeneration., Results: Isoflurane at MAC significantly decreased blood pressure, heart rate, cardiac output, and systemic vascular resistance by 30-48% (n = 16; P < 0.05). CNS 5161A (n = 12) had no significant cardiovascular effects. All concentrations of CNS 5161A caused a significant reduction (21-29%) of the MAC of isoflurane (n = 12; P < 0.05). CNS 5161A, at serum concentrations greater than 25 ng/ml, completely inhibited c-fosmRNA and c-FOS protein expression in hippocampal neurons after 120 min of HCA, attenuated neuronal degeneration, and improved functional outcome by 47% (P < 0.05)., Conclusions: CNS 5161A at neuroprotective concentrations before CPB-HCA significantly reduces the MAC of isoflurane without cardiovascular effects.

In a hemodynamically compromised neonate with complete transposition and intact ventricular septum (concordant atrioventricular and discordant ventriculo-arterial connections), it became necessary to control severe congestive heart failure. The arterial switch operation had been delayed because of intracranial bleeding and subsequent coagulopathy. The cardiac failure was reversed by surgical banding of the patent arterial duct. The arterial switch was performed successfully one week later.

There is a risk of myocardial ischemia in patients with pulmonary atresia and intact ventricular septum associated with right ventricle dependent coronary circulation, especially during open heart operation. Cardiopulmonary bypass unloads the right ventricle, and thereby reduces the coronary perfusion pressure in an area that is wholly or partly dependent on the right ventricle. We present a veno-venous bypass technique to keep the right ventricle beating and ejecting to supply the oxygenated blood into the right ventricle dependent myocardium and consequently to prevent myocardial ischemia during right heart bypass operation.

The objective was to describe the epidemiologic, clinical, bacteriologic and therapeutic features of seven infants who developed sternal wound and mediastinal infections following palliation and/or repair procedures for congenital heart disease. A retrospective chart review was used. All infants with sternal wound and mediastinal infections were < 30 days of age at the initial operative procedure. Six of the infants had hypoplastic left heart syndrome, and one had complete transposition. Two infants required delayed closure of their chest wound. Three infants had superficial sternal infections and presented at a mean of 12 days postoperatively. Four infants had infection of the deep mediastinal structures: they were all asymptomatic and had purulent collections in their mediastinum at their second palliative operation, which was performed at a mean of 120 days after the initial surgery. Staphylococcus aureus, or coagulase-negative Staphylococcus, was isolated from the wound and/or blood of six infants. All infants with mediastinal infections were managed with operative debridement. Infants with superficial infections underwent local debridement. All infants received long-term intravenous antibiotics. Mediastinal infections in infants undergoing palliative staged procedures for congenital heart lesions may be chronic and indolent, resulting in delayed repair of congenital heart lesions.

Objective: Concern about the durability of small homograft cardiac valves has been expressed by surgeons, and evidence has been found that homograft valves evoke a recipient immune response. We reviewed our experience with homograft valves for evidence of rejection., Methods: A search of our files revealed 11 homograft cardiac valves removed at reoperation and one at autopsy. Six valves were from adults, five were from infants, and one was from a 13-year-old child. Immunohistochemical studies with antibodies against smooth muscle actin, CD20, CD43, CD34, and CD68 were performed on the homografts containing inflammatory infiltrates. These valves happened to be the valves from the five infants. These five valves were also stained with Gram and Gomori's methenamine silver stains., Results: The failed homografts from the adults and 13-year-old child showed leaflet calcification, fibrosis, and degeneration, but no inflammation. The valves from the infants all failed in less than 8 months. The valve leaflets were thickened, and the valve leaflets and aortic sleeves contained a hyperplastic intimal layer with numerous spindle cells positive for smooth muscle actin embedded in a glycosaminoglycan matrix. The homografts contained multiple foci of inflammation consisting of T lymphocytes (in all five infant valves) and B lymphocytes (in three of the five infant valves). Special stains for organisms were negative., Conclusions: Rapid failure plus lymphocytic infiltration in valve leaflets and aortic sleeves is consistent with rejection. The hyperplastic intima is similar to coronary arteries in transplant-associated vascular disease. Our observations are consistent with other reports of rapid failure of homograft valves in this age group.

An infant with hypoplastic left heart syndrome presented for surgical repair at 9 months of age, the ductus having remained open in the presence of a restrictive atrial septal defect. In addition, an anomalous left coronary artery originating from the right pulmonary artery was found. After preliminary blade/balloon atrial septostomy, a successful modified Norwood procedure with concomitant reimplantation of the anomalous coronary artery was performed.

Background: The objective of this study was to review anatomic features and surgical strategies in children with double-outlet right ventricle (DORV) and to assess risk factors for early mortality., Methods and Results: Records were reviewed of all children with DORV undergoing surgery between 1978 and 1993. Noncomplex patients (group 1) had atrioventricular (AV) concordance, a single ventricular septal defect (VSD), balanced ventricles, no straddling AV valves, and no major pulmonary artery anomaly. Group 2 (complex) comprised all remaining patients. Independent risk factors analyzed included location of the main VSD, presence of additional VSDs, coarctation, ventricular outflow obstruction, ventricular hypoplasia, age at operation, operation before 1985, previous palliation, and type of definitive operation. Of 193 patients, 117 were in group 1 and 76 in group 2. In 148 patients, biventricular repair was undertaken, including 111 of 117 group 1 patients and 37 of 76 group 2 patients. Early mortality was higher among group 2 patients undergoing biventricular repair than among group 1 patients (8 of 37 versus 4 of 111, P<.005) and higher than group 2 patients undergoing a Fontan procedure (none of 29, P<.01). Aortic arch obstruction, operation before 1985, and multiple VSDs were significant risk factors for mortality. Age <1 month (P<.05) and multiple VSDs (P<.005) were independent risk factors after definitive repair. Up-to-date follow-up is available on 144 surviving patients, with 127 (88%) in New York Heart Association class I and the remaining 17 in class II. Overall 10-year survival probability was 81%, whereas probability of survival, free from reoperation (after definitive surgery), was 65% at 10 years., Conclusions: Biventricular repair can be achieved in most patients with DORV with low risk. In complex DORV, a Fontan procedure is associated with a lower surgical mortality.

Background: Congenitally corrected transposition of the great arteries is a complex cardiac lesion, usually associated with ventricular septal defect, left ventricular outflow tract obstruction, and tricuspid valve abnormalities. A subset of patients without left ventricular outflow tract obstruction have undergone Senning plus arterial switch operation in an attempt to place the left ventricle in the systemic circuit and the right ventricle in the pulmonary circuit., Methods: Fourteen patients have had the operation performed since July 1989. Age and weight medians were 12 months (range, 0.5 to 120 months) and 8.2 kg (range, 3.2 to 34 kg). All but 1 patient had a left ventricular to right ventricular pressure ratio greater than 0.7, due to a large ventricular septal defect (with or without a previous pulmonary artery band), severe congestive heart failure caused by right ventricular dysfunction and tricuspid insufficiency, or a pulmonary artery band for left ventricular retraining. At least 10 patients had strong contraindications to "classic" repair, including right ventricular hypoplasia (n = 2), moderate to severe right ventricular dysfunction (n = 5), or moderate to severe tricuspid insufficiency (n = 9)., Results: There was one hospital death, occurring in a neonate (7%; 95% confidence interval = 0% to 34%). Actuarial survival beyond 10 months is 81% (95% confidence interval = 42% to 95%), currently with 389 patient-months of total follow-up time. The median grade of tricuspid insufficiency fell from 3/4 preoperatively to 1/4 postoperatively (p = 0.003). Right ventricular function is normal in 11/12 current survivors, all but 1 of whom are in New York Heart Association class I or II., Conclusions: Senning plus arterial switch operation is a good option for selected patients with congenitally corrected transposition of the great arteries with a similar or lower early risk (as compared with classic repairs). Some of the long-term problems associated with congenitally corrected transposition of the great arteries may be avoided with this strategy.

We describe the clinical, histopathologic, and angiographic findings in four children with congenital abnormalities of the great vessels of unknown cause, comprising either single or multiple arterial aneurysms, aortic/arterial dilatation, vessel tortuosity, or combinations of these abnormalities. Two children had early and severe respiratory distress due to aneurysmal compression of the trachea. All children had diffuse dilatation of several arteries, and two children also had tortuosity of multiple arteries. Progression of these abnormalities was clearly evident in one child, in whom diffuse vessel irregularity and tortuosity affected intra-abdominal, and intra and extra-cranial arteries. One child died at 5 years, while the other three have undergone successful surgical repair in the first 3 months of life and are now well, between age 2.5 and 7 years. The phenotype of each child appears unique but all have in common the rare finding of aneurysms of the aorta and main pulmonary artery. Congenital aortic aneurysms did not occur as an isolated finding in any of these children.

Early intervention is necessary in neonates with critical aortic stenosis. The advent of alternate therapy, particularly balloon aortic valvuloplasty, requires a reappraisal of the traditional surgical approach, including the efficacy of initial transvalvar gradient reduction and freedom from recurrence of obstruction in the longer term. This report describes a series of 33 consecutive infants who underwent surgical aortic valvotomy in the first month of life. The hospital mortality was 18 percent with a 5-year probability of survival of 66 percent (90 percent CI, 50 percent to 79 percent). Fourteen reinterventions, nine reoperations and five balloon dilatations, were required at a median age of 0.8 years (range 9 days to 6 years). Three patients died after reintervention (one early and two late). The median follow-up time was 5.8 years (range 0.2 to 14 years). At last follow-up Doppler investigation the average Doppler mean and peak gradients were 34 mm Hg and 18 mm Hg, respectively. Open valvotomy in neonatal aortic valve stenosis allows the use of an appropriate surgical approach with low initial mortality and satisfactory 5-year freedom from reintervention.

Objectives: To assess the accuracy of pulse oximetry under hypothermic conditions in neonates and infants undergoing cardiac surgery, and to assess the effect of probe site as well as probe site skin temperature on the reliability of pulse oximetry., Design: Prospective Study., Setting: Cardiac operating room and intensive care unit of children's hospital., Patients: Twenty-five infants <3 months of age undergoing cardiac surgery with cardiopulmonary bypass., Interventions: Pulse oximeter readings (Sp O2) from probes placed on the hand and foot were recorded at various skin temperatures and compared with hemoximeter oxygen saturations (Sa O2) obtained on simultaneously drawn arterial blood samples. Core temperature, arterial pressure and vasodilator use were recorded simultaneously., Measurements and Main Results: Pulse oximetry bias (Sp O2 - Sa O2) increased to an unacceptable range (>+3% or <-3%) in 45.5% of the readings at foot probe site temperatures of <27 degrees. Pulse oximetry bias was within an acceptable range in 94.7% of the readings at temperatures >29 degrees. There was no significant difference between oximeter readings obtained from two probe sites (hand and foot). Administration of phenoxybenzamine improved the accuracy of pulse oximetry in ten infants at skin temperature of <27 degrees., Conclusions: Pulse oximetry readings in small infants are likely to be unreliable at skin temperatures of <27 degrees, irrespective of probe site. Intravenous phenoxybenzamine appeared to improve the accuracy of pulse oximetry at low temperatures.