Twenty-year experience with heart transplantation for infants and children with restrictive cardiomyopathy: 1986-2006.

Idiopathic restrictive cardiomyopathy (RCM) is a rare cardiomyopathy in children notable for severe diastolic dysfunction and progressive elevation of pulmonary vascular resistance (PVR). Traditionally, those with pulmonary vascular resistance indices (PVRI) >6 W.U. x m(2) have been precluded from heart transplantation (HTX). The clinical course of all patients transplanted for RCM between 1986 and 2006 were reviewed. Preoperative, intraoperative and postoperative variables were evaluated. A total of 23 patients underwent HTX for RCM, with a mean age of 8.8 +/- 5.6 years and a mean time from listing to HTX of 43 +/- 60 days. Preoperative and postoperative (114 +/- 40 days) PVRI were 5.9 +/- 4.4 and 2.9 +/- 1.5 W.U. x m(2), respectively. At time of most recent follow-up (mean = 5.7 +/- 4.6 years), the mean PVRI was 2.0 +/- 1.0 W.U. x m(2). Increasing preoperative mean pulmonary artery pressure (PA) pressure (p = 0.04) and PVRI > 6 W.U. x m(2) (chi(2)= 7.4, p < 0.01) were associated with the requirement of ECMO postoperatively. Neither PVRI nor mean PA pressure was associated with posttransplant mortality; 30-day and 1-year actuarial survivals were 96% and 86%, respectively. Five of the seven patients with preoperative PVRI > 6 W.U. x m(2) survived the first postoperative year. We report excellent survival for patients undergoing HTX for RCM despite the high proportion of high-risk patients.

Bidirectional cavopulmonary anastomosis: impact on diastolic ventricular function indices.

Systolic ventricular function has been demonstrated to remain unchanged following bidirectional cavopulmonary anastomosis (BCPA). The effects of BCPA on diastolic ventricular performance have not been critically assessed. The objective of this study was to evaluate the changes in diastolic ventricular function indices early after BCPA. Nineteen patients were enrolled prospectively. Transthoracic echocardiograms were performed at a median of 4 days prior to and 5 days subsequent to BCPA. Diastolic and systolic echocardiographic indices of ventricular performance were measured for the dominant ventricle. End diastolic volume decreased postoperatively (71.1 +/- 21.1 vs 68.08 +/- 17.9 ml/m2, p = 0.05). Tei index increased postoperatively (0.51 +/- 0.2 vs 0.62 +/- 0.1, p = 0.002), whereas inflow Doppler E velocity (70.3 +/- 13 vs 56.3 +/- 24.7 cm/sec, p = 0.04), E/A ratio (1.18 +/- 0.52 vs 0.84 +/- 0.2, p = 0.02), tissue Doppler E' velocity (9.5 +/- 2.5 vs 6.4 +/- 3.2 cm/sec, p = 0.03) and diastolic flow propagation velocity (56.5 +/- 12 vs 52.8 +/- 11 cm/sec, p = 0.04) all decreased. There was no change in ventricular mass, area change fraction, heart rate, or inflow Doppler A or tissue Doppler A' and S' velocities. This study demonstrated that diastolic indices of ventricular performance are altered indicating decreased diastolic function early following BCPA. Whether this observation is a result of a change in ventricular mass:volume ratio, loading conditions of the ventricle, ventricular geometry, or the effects of cardiopulmonary bypass remains to be determined.

Postoperative hemodynamics after Norwood palliation for hypoplastic left heart syndrome.

Hemodynamics after Norwood palliation for hypoplastic left heart syndrome (HLHS) have been incompletely characterized, although emphasis has been placed on the role that an excess pulmonary-to-systemic blood flow ratio (Qp/Qs) may play in causing hemodynamic instability. Studies suggest that maximal oxygen delivery occurs at a Qp/Qs < 1. However, it remains unclear to what extent cardiac output can increase with increasing pulmonary perfusion. One approach is to use the oxygen excess factor omega, an index of systemic oxygen delivery, and compare omega with measured Qp/Qs. We measured Qp/Qs and omega in neonates after Norwood palliation for HLHS, and determined how they were related. In addition, we determined the temporal course of surrogate indexes of systemic perfusion in the early postoperative period. Arteriovenous oxygen saturation difference, blood lactate, and omega were recorded on admission and every 3 to 12 hours for 2 days in 18 consecutive infants with HLHS or variant after Norwood palliation. Three infants required extracorporeal membrane oxygenation (ECMO) 6 to 9 hours after admission. These infants had higher Qp/Qs, blood lactate, arteriovenous oxygen saturation difference, and lower omega than non-ECMO patients. In non-ECMO patients between admission and 6 hours, omega decreased significantly despite no appreciable change in Qp/Qs. We conclude that: (1) Oxygen delivery is significantly decreased at 6 postoperative hours unrelated to Qp/Qs. This modest decline in oxygen delivery is insufficient to compromise tissue oxygenation. (2) Patients requiring ECMO have significant derangements in oxygen delivery.

Inducibility of intra-atrial reentrant tachycardia after the first two stages of the Fontan sequence.

OBJECTIVES: We sought to examine the incidence and possible factors for inducible intra-atrial reentrant tachycardia (IART) in a group of patients after two stages of the Fontan sequence but before the operation. BACKGROUND: Intra-atrial reentrant tachycardia occurs in 10% to 40% of patients after the Fontan operation. No data are available regarding the potential for IART after the first two stages of the Fontan sequence but before the operation. METHODS: The IART induction protocol included programmed extrastimulation and rapid atrial pacing, with and without isoproterenol. RESULTS: The median age of the study group (n = 44, 27 males) was 1.7 years (range 1.2 to 5.2). Forty patients were in sinus rhythm. Twelve patients (27%) had inducible, sustained (>1 min) IART. Three patients (8%) had inducible, nonsustained IART. Bivariate analysis revealed that patients with sustained IART were significantly older at their second operation (median 0.54 vs. 0.40 years, p = 0.05). Multivariate logistic modeling revealed that older age (> or =0.55 years) at the second palliative operation (p = 0.04), older age (> or =1.95 years) at evaluation before the Fontan sequence (p = 0.04) and female gender (p = 0.03) were independently associated with sustained IART. A trend toward a greater frequency of sustained IART was seen in those patients with moderate or severe atrioventricular valve regurgitation (p = 0.07) and in those with resection of the atrial septum (p = 0.06). CONCLUSIONS: The rate of inducible, sustained IART in a group of patients before the Fontan operation is 27% and is associated with older age at the time of second-stage palliation, older age at pre-Fontan evaluation and female gender.

Neurodevelopmental outcome of patients after the fontan operation: A comparison between children with hypoplastic left heart syndrome and other functional single ventricle lesions.

OBJECTIVE: To compare neurodevelopmental outcome (NDO) in patients with hypoplastic left heart syndrome (HLHS), other functional single ventricle lesions, and the standard population and to investigate predictors of NDO in the population of children with functional single ventricle (FSV). STUDY DESIGN: A time- and age-defined cohort of patients with the Fontan circulation was recruited to participate in neurodevelopmental testing, behavioral evaluation, and imaging of the central nervous system. The Wechsler Intelligence test was the primary measure of NDO. Analysis included comparison of patients with HLHS with other patients with functional single ventricles. Other potential clinical predictors of NDO were investigated. RESULTS: The mean Full Scale Wechsler Intelligence score was 101.4+/-5.4. For the HLHS subgroup the mean Full Scale Wechsler score was 93.8+/-7.3, and for the non-HLHS subgroup it was 107.0+/-7.0. Although the HLHS group had significantly lower scores than the non-HLHS subgroup, neither subgroup scored significantly different from the standard population on the Wechsler Scales. Socioeconomic status, circulatory arrest, and perioperative seizures also were predictive of neurodevelopmental outcome. CONCLUSION: Neurodevelopmental and behavioral outcome in patients who have undergone the Fontan procedure including patients with HLHS is good in the preschool and early school years, with Wechsler Intelligence scores generally in the normal range.

Complete repair of tetralogy of Fallot in the neonate: results in the modern era.

OBJECTIVE: To review more than a decade of experience with complete repair of tetralogy of Fallot (TOF) in neonates at the University of Michigan; to assess early and late survival, perioperative complications, and the incidence of reoperation; and to analyze patient, procedural, and morphologic risk factors to determine their effects on outcome. SUMMARY BACKGROUND DATA: Palliation of TOF with systemic-to-pulmonary artery shunts has been the accepted standard for symptomatic neonates and infants. Complete repair has traditionally been reserved for infants older than 6 months of age because of the perception that younger and smaller infants face an unacceptably high surgical risk. RESULTS: A retrospective review from August 1988 to November 1999 consisted of 61 consecutive symptomatic neonates with TOF who underwent complete repair. Thirty-one patients had TOF with pulmonary stenosis, 24 had TOF with pulmonary atresia, and 6 had TOF with nonconfluent pulmonary arteries. The mean age at repair was 16 +/- 13 days, and the mean weight was 3.2 +/- 0.7 kg. Before surgery, 36 patients were receiving an infusion of prostaglandin, 26 were mechanically ventilated, and 11 required inotropic support. Right ventricular outflow tract obstruction was managed with a transannular patch in 49 patients and a right ventricle-to-pulmonary artery conduit in 12. Cardiopulmonary bypass time averaged 71 +/- 26 minutes. Hypothermic circulatory arrest was used in 52 patients (mean 38 +/- 12 minutes). After cardiopulmonary bypass, the average intraoperative right/left ventricular pressure ratio was 55% +/- 13%. There were no new clinically apparent neurologic sequelae after repair. The postoperative intensive care unit stay was 9.1 +/- 8 days, with 6.8 +/- 7 days of mechanical ventilation. There was one hospital death from postoperative necrotizing enterocolitis on postoperative day 71 and four late deaths, only one of which was cardiac-related. Actuarial survival was 93% at 5 years. Follow-up was available for all 60 hospital survivors and averaged 62 months (range 1-141 months). Twenty-two patients required a total of 24 reoperations at an average interval of 26 months after repair. Indications for reoperation included right ventricular outflow tract obstruction (19), branch pulmonary artery stenosis (11), severe pulmonary insufficiency (4), and residual ventricular septal defect (1). The 1-month, 1-year, and 5-year freedom from reoperation rates were 100%, 89%, and 58%, respectively. CONCLUSIONS: Complete repair of TOF in the neonate is associated with excellent intermediate-term survival. Although the reoperation rate is significant, this is to be expected with the complex right ventricular outflow tract and pulmonary artery anatomy seen in symptomatic neonates and the need for conduit replacement in patients with TOF with pulmonary atresia.

High intensity focused ultrasound effect on cardiac tissues: potential for clinical application.

High intensity focused ultrasound (HIFU) is an evolving technology with potential therapeutic applications. Utilizing frequencies of 500 kHz to 10 MHz, HIFU causes localized hyperthermia at predictable depths without injuring intervening tissue. Applications in neurosurgery, urology, oncology and, more recently, cardiology for selective cardiac conduction tissue ablation have been promising. A 'noninvasive' technique for causing localized tissue damage to relieve hemodynamic and life-threatening obstruction in patients with congenital cardiac anomalies could replace more invasive procedures. We, therefore, investigated the ability of HIFU to create lesions in mammalian cardiac tissues ex vivo. Porcine valve leaflet, canine pericardium, human newborn atrial septum, and right atrial appendage were studied. Specimens were mounted and immersed in a water bath at room temperature. Using a 1-MHz phased array transducer, ultrasound energy was applied with an acoustic intensity of 1630 W/cm(2) or 2547 W/cm(2) until a visible defect was created (duration 3 to 25 sec). Macroscopic and microscopic examination demonstrated precise defects ranging from 3 to 4 mm in diameter. No damage was identified to the surrounding tissues. Our study concluded that HIFU can create precise defects in different cardiac tissue without damage to the surrounding tissue. Further investigation is needed to assess potential clinical uses of this technology.

Serial blood lactate measurements predict early outcome after neonatal repair or palliation for complex congenital heart disease.

OBJECTIVES: Neonates with congenital heart disease may appear hemodynamically stable after operation and then suddenly experience catastrophic decompensation. An improved means of predicting which infants will suddenly die in the early postoperative period may lead to lifesaving interventions. Studies indicate that blood lactate level is proportional to tissue oxygen debt, but information linking lactate levels with outcome in infants after operation is limited. We sought to determine whether a change in lactate level over time was predictive of a poor outcome defined as death within the first 72 hours or the need for extracorporeal membrane oxygenation. METHODS: To test this hypothesis, we studied prospectively 46 infants who were less than 1 month old and were undergoing complex cardiac surgical palliation or repair. Postoperative arterial oxygen saturation, bicarbonate, and lactate levels were recorded on admission to the intensive care unit and every 3 to 12 hours for the first 3 days. RESULTS: Thirty-seven patients had a good outcome, and 9 patients had a poor outcome. Mean initial lactate level was significantly greater in patients with a poor outcome (9.4 +/- 3.8 mmol/L) than in patients with a good outcome (5.6 +/- 2.1 mmol/L; P =.03). However, an elevated initial lactate level of more than 6 mmol/L had a low positive predictive value (38%) for poor outcome. In contrast, a change in lactate level of 0.75 mmol/L per hour or more was associated with a poor outcome (P <.0001) and predicted a poor outcome with an 89% sensitivity value, a 100% specificity value, and a 100% positive predictive value. CONCLUSIONS: Serial blood lactate level measurements may be an accurate predictor of death or the requirement for extracorporeal membrane oxygenator support for patients who undergo complex neonatal cardiac surgery.

Use of a single coil transvenous electrode with an abdominally placed implantable cardioverter defibrillator in children.

While transvenous defibrillator electrode placement avoiding a thoracotomy is preferable, electrode size, a large intercoil spacing, and the need for subclavicular device placement preclude this approach in most children. We investigated a single RV coil to an abdominally placed active can ICD device. Five children ages 8-16 years (weight 21-50 kg, mean 35 kg) underwent ICD placement. Placement of a single coil Medtronic model 6932 or 6943 electrode was performed via the left subclavian vein approach and the electrode positioned in the RV apex with the coil lying along the RV diaphragmatic surface. The ICD (Medtronic Micro Jewel II model 7223 Cx) was implanted in a left abdominal pocket with the lead tunneled from the infraclavicular region to the pocket. Implant DFTs were < or = 15 J using a biphasic waveform. DFTs rechecked within 3-month postimplant were unchanged. Lead impedance at implant ranged from 38 to 56 omega, mean 51 omega. Follow-up was 3-21 months (total 82 months) with no electrode dislodgment, lead fractures, or inappropriate discharges. Two of the five patients have had successful appropriate ICD discharges. Transvenous ICD electrode placement can be performed in children as small as 20 kg with the device implanted in a cosmetically acceptable abdominal pocket that is well tolerated. Excellent DFTs can be achieved. This approach avoids a thoracotomy in all but the smallest child, does not require subclavicular placement of the device, and avoids use of a second intravascular coil.

Primary repair of aortic arch obstruction with ventricular septal defect in preterm and low birth weight infants.

OBJECTIVE: Previous reports have suggested that prematurity and low birth weight are risk factors for definitive surgical intervention in congenital cardiac malformations. The following data review our experience with primary repair of the complex malformation of aortic arch obstruction with ventricular septal defect (VSD) in this patient population. METHODS: Since 1988, 21 consecutive preterm (

Early results of the fontan procedure in one hundred consecutive patients with hypoplastic left heart syndrome.

OBJECTIVES: The purpose of this study was to review a large, single institutional experience with the Fontan procedure for patients with hypoplastic left heart syndrome. METHODS: One hundred consecutive patients with "classic" hypoplastic left heart syndrome underwent Fontan palliation between February 1992 and April 1998. Patient demographic, morphologic, and procedural variables were examined and analyzed. In particular, two different surgical techniques were used: technique I (February 1992 to December 1995) employed cardiopulmonary bypass and moderate systemic hypothermia, and technique II (December 1995 to April 1998), profound hypothermia and circulatory arrest. A retrospective review of medical records was performed and variables were examined and analyzed. RESULTS: Hospital survival for the entire cohort was 89% (95% CI 83%-95%). The technique of operation, cardiopulmonary bypass time, and aortic crossclamp time were each strongly associated with survival. Survival for patients treated by technique I was 79% (95% CI 68-91%; n = 48) and for those treated by technique II, 98% (95% CI 94%-100%; n = 52). Cardiopulmonary bypass and crossclamp times were also highly correlated with time to extubation and length of intensive care unit stay. Preoperative pulmonary artery pressure was correlated with survival; preoperative oxygen saturation, right atrial pressure, pulmonary vascular resistance, pulmonary artery size, extent of aortopulmonary artery collaterals, and echocardiographic estimates of ventricular function and tricuspid regurgitation were not correlated with survival. CONCLUSIONS: Our recent experience with Fontan palliation for patients with hypoplastic left heart syndrome suggests that it is attended by low perioperative mortality. The precise operative technique used appears to be an important determinant of outcome, with the duration of cardiopulmonary bypass and crossclamping being particularly significant.

Mycotic pseudoaneurysm associated with aortic coarctation.

Development of a mycotic aneurysm or pseudoaneurysm after subacute bacterial endarteritis is uncommon. Nonetheless, patients with coarctation of the aorta are more likely to develop this complication. We describe a case of a large pseudoaneurysm discovered in a child with a previously undiagnosed aorta coarctation. Successful repair was performed with the aid of partial left heart bypass and the use of an interposition graft. A high index of suspicion is necessary to accurately diagnose this rare but life-threatening entity.

RSR13, a synthetic allosteric modifier of hemoglobin, improves myocardial recovery following hypothermic cardiopulmonary bypass.

BACKGROUND: During hypothermic blood cardioplegia, oxygen delivery to myocytes is minimal with ineffective anaerobic metabolism predominating. RSR13, 2-[4-[[(3,5-dimethylanilino) carbonyl]methyl]phenoxy]-2-methylpropionic acid, a synthetic allosteric modifier of hemoglobin (Hb), increases release of oxygen from Hb, increasing oxygen availability to hypoxic tissues, and reverses the hypothermia-dependent increase in Hb oxygen affinity. We studied recovery of myocardial mechanical and metabolic function and examined myocardial morphology after cardioplegia, comparing RSR13 (1.75 mmol/L)-supplemented blood (RSR13-BC) to standard blood cardioplegia (BC). METHODS AND RESULTS: Twelve dogs underwent 15 minutes of 37 degrees C global ischemia on cardiopulmonary bypass, followed by 75 minutes of hypothermic cardioplegia (13 degrees C) with either BC (n=6) or RSR13-BC (n=6). There were no differences in baseline function between groups. Cardiac function was assessed after 30 minutes of 37 degrees C reperfusion (BC versus RSR13-BC, respectively) by measuring: % return to normal sinus rhythm (0/100%), % of baseline+dP/dt (33.7+/-1.7/76.3+/-1.9), % of baseline-dP/dt (26.6+/-2.0/81.1+/-1.6), stroke volume (3.5+/-0.5/7.1+/-0.9 mL), cardiac output (340+/-20/880+/-40.3 mL/min), and LVEDP (11.3+/-2.2/0. 3+/-2.9 mm Hg). Postischemic oxidative and metabolic parameters including myocardial lactate, pyruvate, ATP content, and percent water content also were determined. Histological analysis demonstrated preservation of endothelial and myocyte morphology in hearts receiving RSR13-BC compared with BC. CONCLUSIONS: These results indicate that in the setting of hypothermic cardiopulmonary bypass, RSR13 improves recovery of myocardial mechanical and metabolic function compared with standard hypothermic BC. Findings from this study suggest that RSR13-BC, by decreasing hemoglobin oxygen affinity, improves oxidative metabolism and preserves cellular morphology, resulting in significantly improved contractile recovery on reperfusion.

Biventricular repair for aortic atresia or hypoplasia and ventricular septal defect.

OBJECTIVE: Aortic valve atresia or hypoplasia can present with a ventricular septal defect and a normal mitral valve and left ventricle. These patients may be suitable for biventricular repair, although the optimal initial management strategy remains unknown. METHODS: From January 1991 through March 1999, 20 patients with aortic atresia or hypoplasia and ventricular septal defect underwent operation with the intent to achieve biventricular repair. Aortic atresia was present in 7 patients, and aortic valve hypoplasia was present in 13 patients. Among those patients with aortic hypoplasia, Z-scores of the aortic valve anulus ranged from -8.8 to -2.7. Associated anomalies included interrupted aortic arch (n = 12 patients), coarctation (n = 6 patients), aortopulmonary window (n = 1 patient), and heterotaxia (n = 1 patient). Nine patients were staged with an initial Norwood procedure followed by biventricular repair in 8 patients. One patient awaits biventricular repair after a Norwood procedure. The conditions of 11 patients were corrected with a single procedure. RESULTS: Among the 9 patients who underwent staged repair, there were no deaths after the Norwood procedure and 1 death after biventricular repair. For the 11 patients who underwent a primary biventricular repair, there was 1 early death and 2 late deaths from noncardiac causes. Follow-up ranged from 1 to 85 months (mean, 28 months). Actuarial survival for the entire group was 78% +/- 10% at 5 years and was not significantly different between staged repair (89%) and primary biventricular repair (73%). CONCLUSIONS: Both primary and staged biventricular repair for patients with aortic atresia or hypoplasia and ventricular septal defect may be performed with good late survival. Refinements in technique of conduit insertion and arch reconstruction have resulted in primary biventricular repair becoming our preferred approach.

Hemi-Fontan procedure for hypoplastic left heart syndrome: outcome and suitability for Fontan.

BACKGROUND: Following the Norwood procedure for hypoplastic left heart syndrome (HLHS), pulmonary artery distortion and hypoplasia are common and may negatively impact late outcome. The hemi-Fontan procedure (HFP) augments the central pulmonary arteries and establishes a connection between the right atrial/superior vena cava junction and the pulmonary arteries, while excluding the inferior vena cava. METHODS: The hospital records of all 114 patients undergoing a HFP for HLHS between August 1993 and April 1998 were reviewed to assess patient, procedural, and morphologic determinations of outcome. The results of cardiac catheterization, Doppler/echocardiography, 12 lead electrocardiograms, hospital and subsequent course, as well as suitability and outcome for the Fontan procedure were analyzed. RESULTS: Mean age was 5.4 months (range 1.5 to 15 months). Right ventricular function was normal in 95 patients, moderately depressed in 14, and severely depressed in five. Tricuspid regurgitation was absent or mild in 91 patients, moderate in 13, and severe in 10. Concomitant procedures included left superior vena cava to pulmonary artery anastomosis (12), tricuspid valve repair (10), pulmonary artery stent placement (3), coarctation repair (2), and aortic pseudoaneurysm repair (1). Hospital survival was 112/114, 98% (95% confidence interval [CI]: 95% to 100%). There were two late deaths, one noncardiac. Sinus rhythm is present in 105 patients (92%, 95% CI: 87% to 97%). To date, 79 of these patients have undergone the Fontan procedure with 74 survivors (94%, 95% CI: 89% to 99%). CONCLUSIONS: The HFP may be performed with excellent results for HLHS. It effectively augments the central pulmonary arteries while preserving sinus rhythm in the majority. In addition, the HFP facilitates the subsequent Fontan procedure and has significantly improved the overall outcome.

Late fenestration closure in the hypoplastic left heart syndrome: comparison of hemodynamic changes.

BACKGROUND AND OBJECTIVES: Although survival of patients with the hypoplastic left heart syndrome treated by staged surgical palliation has improved, hemodynamic data after fenestrated Fontan operation and after fenestration closure have not been reported in this patient population. We sought to describe the hemodynamic status of these patients at cardiac catheterization performed for the purpose of fenestration closure and to compare these data with data from contemporary patients with other forms of univentricular heart. METHODS AND RESULTS: Hemodynamic responses to fenestration closure during cardiac catheterization were reviewed in 40 consecutive patients, including 20 with the hypoplastic left heart syndrome and 20 with other forms of univentricular heart defects. Hemodynamics before fenestration closure (arterial saturation and pressure, Fontan baffle saturation and pressure, pulmonary capillary wedge pressure, systemic arteriovenous oxygen content difference, and right-to-left shunt fraction) were nearly identical between the two groups. Significant (p < 0.05) changes after fenestration closure included increases in arterial saturation (9%), mean arterial pressure (3 mm Hg), and baffle pressure (1 mm Hg) and arteriovenous oxygen content difference (18 ml/L), with near elimination of right-to-left shunting. Cardiac output decreased by 21% and systemic oxygen transport by 13%, with no differences between the two patient groups. Mean baffle pressures were <17 mm Hg in 32 patients (80%). CONCLUSIONS: Hemodynamics after fenestrated Fontan operation and responses to fenestration closure in patients with the hypoplastic left heart syndrome were remarkably similar to that in patients with other univentricular heart defects.

Techniques and results in the management of multiple ventricular septal defects.

OBJECTIVE: The management of patients with multiple ventricular septal defects remains controversial. Primary closure, interventional catheter techniques, and palliative surgery all may have a role, and specific management guidelines remain undefined. METHODS: We reviewed the records of all 33 patients with multiple ventricular septal defects undergoing repair between January 1988 and October 1996. Pulmonary artery hypertension was present in 21 patients (group 1), and pulmonary stenosis was present in the remaining 12 (group 2). Closure was accomplished from a right atriotomy alone in most patients, although an apical left ventriculotomy was used for apical defects. Among group 1 patients, the mean age at repair was 5.9 +/- 0.9 months. Major associated anomalies included coarctation (n = 6), straddling tricuspid valve (n = 1), and critical aortic stenosis (n = 1). Reoperation was performed in two patients for residual ventricular septal defects. Among group 2 patients, the mean age at repair was 6.6 +/- 3.2 years. Major associated anomalies included tetralogy of Fallot (n = 2), pulmonary stenosis (n = 4), double-outlet right ventricle with hypoplastic left ventricle (n = 1), and isolated left ventricular hypoplasia (n = 1). Three required reoperation for residual ventricular septal defect. RESULTS: There were no early or late deaths, no episodes of heart block, and no significant residual ventricular septal defects among group 1 patients. All group 1 patients remain free of significant residual cardiovascular conditions at a mean of 23.4 +/- 5.1 months. Among group 2 patients, there was one early death in a patient with double-outlet right ventricle and left ventricular hypoplasia. Complete heart block occurred in two patients and one required late mitral valve replacement. There were no late deaths, seven remain alive without significant residual defects at a mean of 36.2 +/- 8.0 months, and two required transplantation for left ventricular failure. CONCLUSIONS: Primary repair for infants with multiple ventricular septal defects is associated with good late outcomes. The right atrial approach is satisfactory for most muscular defects, although limited apical left ventriculotomy was used for apical defects. Pulmonary artery banding should be limited to patients with complex associated defects.

Resting coronary flow and coronary flow reserve in human infants after repair or palliation of congenital heart defects as measured by positron emission tomography.

OBJECTIVE: Coronary physiology in infants with congenital heart disease remains unclear. Our objective was to better understand coronary physiology in infants with congenital heart disease. METHODS: We used positron emission tomography with nitrogen 13-labeled ammonia to measure myocardial perfusion at rest and with adenosine (142 micrograms/kg/min x 6 minutes) in five infants after anatomic repair of a congenital heart lesion (group I), and in five infants after Norwood palliation for hypoplastic left heart syndrome (group II). The groups were matched for age, weight, and time from the operation. RESULTS: Resting coronary flow in the left ventricle in group I was 1.8 +/- 0.2 ml/min/gm; resting flow in the right ventricle in group II was 1.0 +/- 0.3 ml/min/gm (p = 0.003). Coronary flow with adenosine was 2.6 +/- 0.5 ml/min/gm in group I and 1.5 +/- 0.7 ml/min/gm in group II (p = 0.02). Absolute coronary flow reserve was the same in both groups (1.5 +/- 0.2 in group I vs 1.6 +/- 0.3 in group II, p = 0.45). Oxygen delivery was reduced in group II compared with group I at rest (16.1 +/- 4.2 ml/min/100 gm vs 28.9 +/- 4.42 ml/min/100 gm, p = 0.02) and with adenosine (25.5 +/- 8.1 ml/min/100 gm vs 42.3 +/- 5.8 ml/min/100 gm, p = 0.02). CONCLUSIONS: Infants with repaired heart disease have higher resting flow and less coronary flow reserve than previously reported for adults. After Norwood palliation, infants have less perfusion and oxygen delivery to the systemic ventricle than do infants with a repaired lesion. This may in part explain why the outcome for patients with Norwood palliation is less favorable than for others.