Chitra Ravishankar

Enalapril in Infants With Single Ventricle Results of a Multicenter Randomized Trial

Background— Angiotensin-converting enzyme inhibitor therapy improves clinical outcome and ventricular function in adults with heart failure. Infants with single-ventricle physiology have poor growth and are at risk for abnormalities in ventricular systolic and diastolic function. The ability of angiotensin-converting enzyme inhibitor therapy to preserve ventricular function and improve somatic growth and outcomes in these infants is unknown. Methods and Results— The Pediatric Heart Network conducted a double-blind trial involving 230 infants with single-ventricle physiology randomized to receive enalapril (target dose 0.4 mg · kg−1 · d−1) or placebo who were followed up until 14 months of age. The primary end point was weight-for-age z score at 14 months. The primary analysis was intention to treat. A total of 185 infants completed the study. There were 24 and 21 withdrawals or deaths in the enalapril and placebo groups, respectively (P=0.74). Weight-for-age z score was not different between the enalapril and placebo groups (mean±SE −0.62±0.13 versus −0.42±0.13, P=0.28). There were no significant group differences in height-for-age z score, Ross heart failure class, brain natriuretic peptide concentration, Bayley scores of infant development, or ventricular ejection fraction. The incidence of death or transplantation was 13% and did not differ between groups. Serious adverse events occurred in 88 patients in the enalapril group and 87 in the placebo group. Conclusions— Administration of enalapril to infants with single-ventricle physiology in the first year of life did not improve somatic growth, ventricular function, or heart failure severity. The results of this randomized trial do not support the routine use of enalapril in this population. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00113087.

Risk factors for interstage death after stage 1 reconstruction of hypoplastic left heart syndrome and variants

OBJECTIVEnThe risk of death during the interstage period remains high after stage 1 reconstruction for single ventricle lesions, despite improved surgical results. The purpose of this study is to identify risk factors for interstage death and to describe the events leading to interstage death.nnnMETHODSnA nested case-control study was conducted of 368 patients who underwent stage 1 reconstruction at a single center between January 1998 and April 2005.nnnRESULTSnAmong the 313 (85%) hospital survivors, there were 33 (10.5%) interstage deaths. Cases more frequently presented with intact or restrictive atrial septum (9 [27%] vs 4 [4%]; P < .001), were older at the time of surgery (5 [2-40] vs 3 [1-42] days; P = .005), had more postoperative arrhythmias (12 [36%] vs 15 [15%]; P = .01), and a higher incidence of airway or respiratory complications (12 [36%] vs 19 [19%]; P = .04). By multivariate analysis, only intact atrial septum (odds ratio 7.6; 95% confidence intervals 1.9-29.6; P = .003) and age at operation greater than 7 days (odds ratio 3.8; 95% confidence intervals 1.3-11.2; P = .017) were predictors of interstage death.nnnCONCLUSIONSnThe presence of intact atrial septum and older age at the time of surgery are associated with a higher risk of interstage death. In addition, postoperative arrhythmia and airway complications are associated with a higher risk of interstage death in univariate analysis. The results of this study provide a focus for interstage monitoring and risk stratification of these high-risk infants, which may improve overall survival.

Extracorporeal membrane oxygenation after stage I reconstruction for hypoplastic left heart syndrome

Objective: Although extracorporeal membrane oxygenation (ECMO) is an acceptable strategy for children with refractory cardiac dysfunction after cardiac surgery, its role after stage I reconstruction for hypoplastic left heart syndrome and its variants is controversial. Our objective is to describe the outcome of “nonelective” ECMO after stage I reconstruction. Design: Retrospective case series. Setting: Pediatric cardiac intensive care unit. Patients: Infants placed on ECMO after stage I reconstruction from January 1998 to May 2005. Interventions: None. Measurements and Main Results: Of the 382 infants who underwent stage I reconstruction during the study period, 36 (9.4%) required ECMO in the postoperative period. There were 22 infants with hypoplastic left heart syndrome. Indications for ECMO included inability to separate from cardiopulmonary bypass in 14 and cardiac arrest in 22. Fourteen infants (38.8%) survived to hospital discharge. Nonsurvivors had longer cardiopulmonary bypass time (150.1 ± 70.0 mins vs. 103.9 ± 30.0 mins, p =. 01). 9/14 infants (64%) supported with ECMO> than 24 hrs after stage I reconstruction survived while only 5/22 infants (22%) requiring ECMO< 24 hrs of stage I reconstruction survived (p =. 02). Of note, all five infants diagnosed with an acute shunt thrombosis were early survivors. Mean duration of ECMO was 50.1 ± 12.5 hrs for survivors and 125.2 ± 25.0 for nonsurvivors (p =. 01). 7/14 early survivors are alive at a median follow-up of 20 months (2–78 months). Conclusions: In our experience, ECMO after stage I reconstruction can be life saving in about a third of infants with otherwise fatal conditions. It is particularly useful in potentially reversible conditions such as acute shunt thrombosis and transient depression of ventricular function.

Epidemiologic features of the presentation of critical congenital heart disease: implications for screening.

OBJECTIVE. Critical congenital heart disease has been proposed as a target of newborn screening. This study aimed to define the incidence and timing of significant physiologic compromise attributable to critical congenital heart disease as well as the distribution of vulnerable lesions. These descriptive parameters must be defined to evaluate the impact and feasibility of any proposed screening strategy. METHODS. A retrospective cohort study of neonates who had critical congenital heart disease and were admitted to a single institution was conducted. Critical congenital heart disease was defined as congenital heart disease that required invasive intervention or resulted in death in the first 30 days of life. Significant physiologic compromise was defined by severe metabolic acidosis, seizure, cardiac arrest, or laboratory evidence of renal or hepatic injury before invasive intervention. Significant physiologic compromise was classified as potentially preventable when it occurred as a result of undiagnosed congenital heart disease after 12 hours of life. RESULTS. Significant physiologic compromise occurred in 76 (15.5%) of 490 patients, and potentially preventable significant physiologic compromise occurred in 33 (6.7%) of 490 patients. Most (83%) significant physiologic compromise as a result of unrecognized congenital heart disease occurred after 12 hours of age. A total of 90.9% of cases of potentially preventable significant physiologic compromise had aortic arch obstruction. The incidence of potentially preventable significant physiologic compromise as a result of congenital heart disease in the general population is estimated to be 1 per 15000 to 1 per 26000 live births. CONCLUSIONS. The incidence and timing of significant physiologic compromise as a result of critical congenital heart disease seems amenable to postnatal screening. Any viable screening strategy must be sensitive for lesions with aortic arch obstruction.

Ventricular assist device-associated anti-human leukocyte antigen antibody sensitization in pediatric patients bridged to heart transplantation

BACKGROUNDnVentricular assist devices (VAD) are associated with the formation of antibodies to anti-human leukocyte antigens (HLA) or sensitization. The incidence and effects of VAD-associated anti-HLA sensitization have not been well studied in the pediatric population.nnnMETHODSnA retrospective review of all patients undergoing VAD implant at our institution from 1998 to 2008 was performed. Panel reactive antibody (PRA) results before VAD implant, after VAD implant, and after orthotopic heart transplantation (OHT) were recorded. Patients who became sensitized (PRA for class I and/or II immunoglobulin G antibodies >or= 10%) on VAD support were compared with non-sensitized patients with regard to demographics, diagnosis, device type, and blood product exposure on VAD support. Outcomes after OHT were also compared between groups.nnnRESULTSnVAD support was initiated in 20 patients (median age, 14.4 years), with 75% survival to OHT or recovery. PRA data before and after VAD implant were available for 17 patients. VAD-associated sensitization developed in 35% of recipients. There were no differences between those sensitized in association with VAD support and non-sensitized patients with regard to age, gender, diagnosis, device type, extracorporeal membrane oxygenation use, or blood product exposure on VAD support. Black race predicted sensitization on VAD (p = 0.02). There were no differences in survival or rejection between groups.nnnCONCLUSIONSnVAD therapy was associated with the development of anti-HLA sensitization in 35% of recipients. Black race predicted sensitization, but there were no differences in overall survival or outcomes after OHT.

Critical heart disease in the neonate: Presentation and outcome at a tertiary care center

Objective: To define the modes of presentation, incidence of major organ dysfunction, predictors of hospital mortality, and adverse outcomes in neonates with critical heart disease admitted to a tertiary care center. Design: Retrospective chart review. Setting: A tertiary care pediatric cardiac intensive care unit and neonatal intensive care unit. Patients: The medical records for all neonates (≤30 days of age) with heart disease admitted to the cardiac intensive care unit or neonatal intensive care unit between October 1, 2002, and September 30, 2003, were reviewed. Interventions: None. Measurements and Main Results: A total of 190 neonates met inclusion criteria during this 1-yr period, of which 146 (77%) had at least one surgical procedure. Single ventricle heart disease was present in 42%. The most common mode of presentation was following a prenatal diagnosis (53%), followed by diagnosis in the newborn nursery (38%) and diagnosis after newborn hospital discharge (8%). The most common presenting findings in the newborn nursery were isolated murmur (38%) or cyanosis (32%), while circulatory collapse (38%) was the most common presentation after discharge. For the entire study cohort, 13% had a known genetic syndrome, 23% had a major noncardiac congenital anomaly, and 16% weighed <2.5 kg. The hospital mortality for the entire cohort was 7.4%. Risk factors associated with an increased risk of hospital mortality included younger age at admission, higher number of cardiopulmonary bypass runs, and need for postoperative cardiopulmonary resuscitation. Total hospital length of stay was >1 month in 17% of neonates. Conclusions: In patients with complex congenital heart disease, including nearly half with single ventricle heart disease, neonatal hospital mortality was 7%. These patients have a high frequency of multiple congenital anomalies, genetic syndromes, low birth weight, and prolonged length of stay.

A contemporary comparison of the effect of shunt type in hypoplastic left heart syndrome on the hemodynamics and outcome at Fontan completion.

OBJECTIVEnWe previously reported no difference in morbidity or mortality in a cohort of infants undergoing stage 1 and 2 reconstructions for hypoplastic left heart syndrome with either a modified Blalock-Taussig shunt or a right ventricular to pulmonary artery conduit. This article compares the hemodynamics and perioperative course at the time of the Fontan completion and reports longer-term survival for this cohort.nnnMETHODSnWe retrospectively reviewed the hospital records of all patients who underwent stage 1 reconstruction between January 2002 and May 2005 and subsequent surgical procedures, as well as cross-sectional analysis of hospital survivors.nnnRESULTSnA total of 176 patients with hypoplastic left heart syndrome or a variant underwent stage 1 reconstruction with either modified Blalock-Taussig shunt (n = 114) or right ventricular to pulmonary artery conduit (n = 62). Shunt selection was at the discretion of the surgeon. The median duration of follow-up was 58 months (range 1-87 months). By Kaplan-Meier analysis, shunt type did not influence survival or freedom from transplant at 5 years (right ventricular to pulmonary artery conduit 61%; 95% confidence limit, 47-72 vs modified Blalock-Taussig shunt 70%; 95% confidence limit, 60-77; P = .55). A total of 107 patients underwent Fontan (69 modified Blalock-Taussig shunts and 38 right ventricular to pulmonary artery conduits) with 98% (105/107) early survival. Patients with a right ventricular to pulmonary artery conduit shunt pre-Fontan had higher pulmonary artery (13 +/- 8 mm Hg vs 11 +/- 3 mm Hg, P = .026) and common atrial (8 +/- 2.3 mm Hg vs 6.8 +/- 2.7 mm Hg, P = .039) pressures. By echocardiography evaluation, there was more qualitative moderate to severe ventricular dysfunction (right ventricular to pulmonary artery conduit 31% [12/36] vs modified Blalock-Taussig shunt 17% [11/67], P = .05) and moderate to severe atrioventricular valve regurgitation (right ventricular to pulmonary artery conduit 40% [14/35] vs modified Blalock-Taussig shunt 16% [11/67], P = .01) in the right ventricular to pulmonary artery conduit group. Use of diuretic therapy, angiotensin-converting enzyme inhibition, reflux medications, and tube feedings were not different between groups. Overall, 5 patients underwent heart transplantation (right ventricular to pulmonary artery conduit 4 vs modified Blalock-Taussig shunt 1, P = .1) before Fontan. There was no difference in age or weight at Fontan, bypass time, intensive care unit or hospital length of stay, postoperative pleural effusions, or need for reoperation between groups.nnnCONCLUSIONSnInterim analyses continue to suggest there is no survival advantage of one shunt type compared with the other. Longer-term follow-up of a randomized patient population remains of utmost importance.

Too Fat or Too Thin? Body Habitus Assessment in Children Listed for Heart Transplant and Impact on Outcome

BACKGROUNDnBody habitus assessment (BHA), be it wasted or obese, is a useful marker of nutritional status and overall medical condition. Wasting and obesity pre-heart transplant adversely affects outcomes in adults. The utility of BHA as a prognostic factor in children post-transplant is unknown.nnnMETHODSnWeight and height at listing and standard growth charts were used to determine the ideal body weight (%IBW) and percentiles for body mass index for age (BMI%) and weight-for-length (W:L%). Wasting was defined as <90%IBW and/or <or=5th percentile for BMI% or W:L%. Obesity was defined as >120%IBW and/or >or=95th percentile BMI% or W:L%. Outcomes of cohorts based on these criteria were compared.nnnRESULTSnFrom June 1990 to December 2006, 180 children, aged 5.81 +/- 6 years, were listed for transplant. Wasting occurred in 66 (37%) and obesity in 22 (12%) children, without differences between diagnoses of cardiomyopathy or congenital heart disease. %IBW was a prognostic factor for survival post-transplant on multivariate analysis: obese patients had a hazard ratio (HR) of 3.82 (95% confidence interval [CI] 1.81 to 8.06) compared with normal BHA (p < 0.001). Wasting had a survival advantage compared with normal BHA (HR 0.51, 95% CI 0.27 to 0.94, p = 0.032). There were no significant differences between cohorts in incidence of infections, first-year rejections or graft vasculopathy.nnnCONCLUSIONSnAbnormal BHA at listing was a prognostic factor for survival post-transplant. Obese children had increased mortality, but wasting did not adversely affect post-transplant survival in our population. Body habitus assessment may risk-stratify children at listing, potentially providing a complex target for intervention.

Juxtaposition of the Atrial Appendages: A Clinical Series of 22 Patients

Abstract. Because the outcome of a large clinical series of patients with juxtaposition of the atrial appendages (JAA) has not previously been reported, a retrospective study was performed on patients diagnosed with JAA at a tertiary medical center. Patients with JAA were identified through a computerized database search, and echocardiograms and medical records of patients with JAA were reviewed. Twenty-two patients with JAA were identified, with an overall incidence of 0.28%. All but 2 patients were diagnosed prospectively with JAA by echocardiography. The lesion-specific incidences and associated lesions were similar to those of large autopsy and surgical series. Abnormal conotruncal anatomy was more frequently seen with juxtaposition of the right atrial appendage (JRAA) vs juxtaposition of the left atrial appendage (JLAA) (14/15 vs 4/7), as was atrial outlet obstruction (6/15 vs 2/7). JLAA was more frequently associated with complex atrioventricular anatomy (3/7 vs 1/15). Patients with JAA underwent single ventricle palliation in 11/22 cases with 6 deaths; biventricular repair was performed in 8/22 cases with no deaths. Surgical outcomes for patients with JRAA and JLAA were similar, and survival was predominantly influenced by suitability for biventricular repair.

Reintervention for arch obstruction after stage 1 reconstruction does not adversely affect survival or outcome at Fontan completion

OBJECTIVEnTo determine the effect of reintervention for coarctation after stage 1 reconstruction for hypoplastic left heart syndrome and variants on survival, suitability for Fontan, and morbidity at Fontan.nnnMETHODSnA retrospective review of echocardiograms, catheterizations, hospital records of patients who underwent stage 1 reconstruction from January 2002 to May 2005, with a cross-sectional analysis of hospital survivors, was performed. Kaplan-Meier curves were derived for patients alive more than 30 days after stage 1 reconstruction.nnnRESULTSnA total of 176 patients underwent stage 1 reconstruction. Forty-three patients (23%) underwent balloon angioplasty (n = 43) or surgical intervention (n = 4) for re-coarctation. Median time to intervention was 123 (1-316) days. Seven of 43 patients (16%) underwent more than 1 balloon angioplasty. Thirty-nine patients underwent intervention before stage 2 reconstruction, and 4 patients had intervention between stage 2 reconstruction and Fontan. Kaplan-Meier curves showed no difference in freedom from death or transplant between patients who did and did not undergo intervention for re-coarctation. Fontan completion was performed in 107 patients. By echocardiogram, the prevalence of moderate to severe ventricular dysfunction between groups was similar at Fontan; however, significant atrioventricular valve regurgitation was more common in patients who required intervention (28/33 vs 40/65, P = .02). Overall Fontan mortality was 2% and not different between groups. Length of stay was not different between patients with and without re-coarctation.nnnCONCLUSIONSnReintervention for coarctation after stage 1 reconstruction is common. Hemodynamic differences between groups did not affect Fontan completion, mortality, or hospital length of stay. Follow-up is necessary to determine the impact of re-coarctation on longer-term mortality and morbidity.