Can pediatric residents interpret electrocardiograms?

The purpose of this study was to assess the electrocardiogram (ECG) interpretation skills of pediatric residents in a controlled environment and determine if the level of residency training (intern vs senior) improves accuracy. A list of ECG diagnoses was provided to four pediatric residency educators with instructions to categorize each diagnosis as follows: I, all residents; II, the majority of residents, including all senior residents; III, less than the majority of residents; and IV, few residents should be able to interpret correctly. Only those categories that the entire panel believed all residents (category I) or all senior residents (category II) should be able to interpret correctly were included. The test included 17 ECGs: 14 category I and 3 category II. A total of 132 residents participated: 78 interns and 54 seniors. Both groups scored below expected levels. Mean correct score among seniors was 10.9 out of the expected 17 (p < 0.001). Mean correct score for interns was 7.7 out of the expected 14 (p < 0.00l). No difference in ECG interpretation accuracy was found between residency programs. In general, pediatric residents' ECG interpretation skills are less accurate than expected. Although there is a trend toward improvement during training, senior residents fell short of the expectations of the panel. We speculate that focused education in this area will improve resident ECG interpretation and benefit patient care by (1) facilitating referral and treatment of patients with cardiovascular disease and (2) decreasing referrals for erroneous interpretations.

Angiogenic proteins in the lungs of children after cavopulmonary anastomosis.

OBJECTIVE: Pulmonary arteriovenous malformations may cause progressive cyanosis after cavopulmonary anastomosis and may develop as a result of abnormal angiogenesis. We used immunohistochemistry to determine whether angiogenic proteins are increased in the lungs of children after cavopulmonary anastomosis. METHODS: Lung specimens were obtained from 13 children after cavopulmonary anastomosis and from 6 control subjects. Specimens were stained with antibodies against vascular endothelial growth factor and its receptor (flk-1/KDR), basic fibroblast growth factor, alpha-smooth muscle actin, CD31, collagen IV, fibronectin, and proliferating cell nuclear antigen. Staining was graded on a scale of 0 to 3. Vessels positive for proliferating cell nuclear antigen were counted in 10 fields per specimen, and the results were averaged. RESULTS: After cavopulmonary anastomosis, patients demonstrated increased staining for vascular endothelial growth factor (P =.03) and its receptor (P =.03) and decreased staining for CD31 (P =.004). Proliferating cell nuclear antigen staining in patients was equivalent to that for control subjects (P =.9). CONCLUSIONS: Lung biopsy specimens from children after cavopulmonary anastomosis demonstrate increased expression of vascular endothelial growth factor and its receptor. These data confirm earlier findings that blood vessels forming after cavopulmonary anastomosis may have reduced intercellular junctions (decreased CD31 staining). Despite the increased numbers of pulmonary vessels that are present in these patients, these vessels are not highly proliferative (proliferating cell nuclear antigen staining equivalent to that of control subjects). These results suggest that vascular endothelial growth factor may be a mediator of angiogenesis in the lungs of children after cavopulmonary anastomosis; however, other factors, such as vascular dilation and remodeling, may also be important.

Association of viral genome with graft loss in children after cardiac transplantation.

BACKGROUND: The survival of recipients of cardiac allografts is limited by rejection, lymphoproliferative disease, and coronary vasculopathy. The purpose of this study in children who had received heart transplants was to evaluate the cardiac allografts for myocardial viral infections and to determine whether the presence of viral genome in the myocardium correlates with rejection, coronary vasculopathy, or graft loss. METHODS: We enrolled heart-transplant recipients 1 day to 18 years old who were undergoing evaluation for possible rejection and coronary vasculopathy. Endomyocardial-biopsy specimens were evaluated for evidence of rejection with the use of standard criteria and were analyzed for the presence of virus by the polymerase chain reaction (PCR). RESULTS: PCR analyses were performed on 553 consecutive biopsy samples from 149 transplant recipients. Viral genome was amplified from 48 samples (8.7 percent) from 34 patients (23 percent); adenovirus was found in 30 samples, enterovirus in 9 samples, parvovirus in 5 samples, cytomegalovirus in 2 samples, herpes simplex virus in 1 sample, and Epstein-Barr virus in 1 sample. In 29 of the 34 patients with positive results on PCR (85 percent), an adverse cardiac event occurred within three months after the positive biopsy, and 9 of the 34 patients had graft loss due to coronary vasculopathy, chronic graft failure, or acute rejection. In 39 of the 115 patients with negative results on PCR (34 percent), an adverse cardiac event occurred within three months of the negative PCR finding; graft loss did not occur in any of the patients in this group. The odds of graft loss were 6.5 times as great among those with positive results on PCR (P=0.006). The detection of adenovirus was associated with considerably reduced graft survival (P=0.002). CONCLUSIONS: Identification of viral genome, particularly adenovirus, in the myocardium of pediatric transplant recipients is predictive of adverse clinical events, including coronary vasculopathy and graft loss.

Is arrhythmia detection by automatic external defibrillator accurate for children?: sensitivity and specificity of an automatic external defibrillator algorithm in 696 pediatric arrhythmias.

BACKGROUND: Use of automatic external defibrillators (AEDs) in children aged <8 years is not recommended. The purpose of this study was to develop an ECG database of shockable and nonshockable rhythms from a broad age range of pediatric patients and to test the accuracy of the Agilent Heartstream FR2 Patient Analysis System for sensitivity and specificity. METHODS AND RESULTS: Children aged

First-stage palliation of complex univentricular cardiac anomalies in older infants.

BACKGROUND: Poor outcomes have been reported for children older than 30 days of age with cardiac anomalies treated with first-stage palliation. METHODS: Our institution has offered first-stage palliation for all such patients regardless of age. The results of this policy were reviewed. RESULTS: Nine patients older than 30 days (median age 67 days, range 36 to 108 days) with diagnoses of hypoplastic left heart syndrome (n = 5), double-outlet right ventricle with hypoplastic aortic arch (n = 2), unbalanced atrioventricular septal defect (n = 1), or single left ventricle with subaortic stenosis (n = 1) underwent surgical palliation. Patients underwent a Norwood (n = 7) or Damus-Kaye-Stancel (n = 2) procedure with a 4- or 5-mm modified Blalock-Taussig shunt; all patients survived the operation. Eight patients underwent a subsequent bidirectional Glenn (2 perioperative deaths, both due to pneumonia; 6 survivors). Two of the 6 surviving patients have undergone Fontan reconstruction and 4 are awaiting Fontan. CONCLUSIONS: Surgical palliation for complex univentricular cardiac malformations can be performed in older infants with results comparable to those in neonates. The use of a larger shunt may contribute to these improved outcomes.

Pulmonary microvessel density is a marker of angiogenesis in children after cavopulmonary anastomosis.

OBJECTIVE: Pulmonary arteriovenous malformations cause progressive cyanosis in children after cavopulmonary anastomosis and may be due to abnormal angiogenesis. We determined the microvessel density, a marker of angiogenesis, in the lungs of children after cavopulmonary anastomosis. METHODS: Lung biopsy specimens were obtained from 8 children after cavopulmonary anastomosis and from 4 control patients. Three of the 8 children undergoing cavopulmonary anastomosis had clinical and angiographic evidence of pulmonary arteriovenous malformations, whereas the other 5 were free of symptoms. Routine histologic and immunohistologic stains were performed with a primary antibody to von Willebrand factor. Microvessel staining for von Willebrand factor was determined for 10 fields (200x) per patient. RESULTS: Patients with and without pulmonary arteriovenous malformations after cavopulmonary anastomosis demonstrated significantly increased microvessel density compared with control subjects (32.7 +/- 2.8 vs 9.3 +/- 4.6, P =.02, and 31.5 +/- 15.7 vs 9.3 +/- 4.6, P =.01, respectively). There was no difference in microvessel density in children with and without clinically apparent pulmonary arteriovenous malformations after cavopulmonary anastomosis (P =.9). The children with pulmonary arteriovenous malformations had numerous greatly dilated vessels that were absent in the asymptomatic children after cavopulmonary anastomosis. CONCLUSIONS: After cavopulmonary anastomosis, pulmonary microvessel density is increased even in the absence of clinically apparent pulmonary arteriovenous malformations, supporting the presence of a constant angiogenic stimulus. Children with clinically apparent pulmonary arteriovenous malformations possess large numbers of greatly dilated pulmonary microvessels, which are absent in asymptomatic children after cavopulmonary anastomosis. These results suggest that the transition to clinically apparent pulmonary arteriovenous malformations may be due to mechanisms that lead to vessel dilation and remodeling.

Triiodothyronine repletion in infants during cardiopulmonary bypass for congenital heart disease.

OBJECTIVE: Cardiopulmonary bypass suppresses circulating thyroid hormone levels. Although acute triiodothyronine repletion has been evaluated in adult patients after cardiopulmonary bypass, triiodothyronine pharmacokinetics and effects have not previously been studied in infants undergoing operations for congenital heart disease. We hypothesized that triiodothyronine deficiency in the developing heart after bypass may adversely affect cardiac function reserve postoperatively. METHODS: Infants less than 1 year old undergoing ventricular septal defect or tetralogy of Fallot repair were randomized into 2 groups. Group T (n = 7) received triiodothyronine (0.4 microg/kg) immediately before the start of cardiopulmonary bypass and again with myocardial reperfusion. Control (NT, n = 7) patients received saline solution placebo or no treatment. RESULTS: These groups underwent similar ischemic and bypass times and received similar quantities of inotropic agents after the operation. The NT group demonstrated significant depression in circulating levels, compared with prebypass levels, for free triiodothyronine and total triiodothyronine at 1, 24, and 72 hours after bypass. Group T demonstrated similar low thyroxine values, but free and total triiodothyronine levels were maintained at prebypass levels for 24 hours and remained elevated over those of group NT (P <.05) at 72 hours. Heart rate was transiently elevated in group T compared with group NT (P <.05), and peak systolic pressure-rate product increased after 6 hours. CONCLUSION: These data imply that (1) triiodothyronine in the prescribed dose prevents circulating triiodothyronine deficiencies and (2) triiodothyronine repletion promotes elevation in heart rate without concomitant decrease in systemic blood pressure. Elevation of peak systolic pressure-rate product implies that triiodothyronine repletion improves myocardial oxygen consumption and may enhance cardiac function reserve after cardiopulmonary bypass in infants.

Vascular endothelial growth factor and basic fibroblast growth factor in children with cyanotic congenital heart disease.

OBJECTIVE: Vascular endothelial growth factor and basic fibroblast growth factor are potent stimulators of angiogenesis. Children with cyanotic congenital heart disease often experience the development of widespread formation of collateral blood vessels, which may represent a form of abnormal angiogenesis. We undertook the present study to determine whether children with cyanotic congenital heart disease have elevated serum levels of vascular endothelial growth factor and basic fibroblast growth factor. METHODS: Serum was obtained from 22 children with cyanotic congenital heart disease and 19 children with acyanotic heart disease during cardiac catheterization. Samples were taken from the superior vena cava, inferior vena cava, and a systemic artery. Vascular endothelial growth factor and basic fibroblast growth factor levels were measured in the serum from each of these sites by enzyme-linked immunosorbent assay. RESULTS: Vascular endothelial growth factor was significantly elevated in the superior vena cava (P =.04) and systemic artery (P =.02) but not in the inferior vena cava (P =.2) of children with cyanotic congenital heart disease compared to children with acyanotic heart disease. The mean vascular endothelial growth factor level, determined by averaging the means of all 3 sites, was also significantly elevated (P =.03). Basic fibroblast growth factor was only significantly elevated in the systemic artery (P =.02). CONCLUSION: Children with cyanotic congenital heart disease have elevated systemic levels of vascular endothelial growth factor. These findings suggest that the widespread formation of collateral vessels in these children may be mediated by vascular endothelial growth factor.

Intermediate-term results in pediatric aortic valve replacement.

BACKGROUND: Aortic valve replacement (AVR) in children is now more commonly performed with human tissue valves. METHODS: The results of 100 consecutive pediatric AVRs (50 mechanical, 50 human) were reviewed. RESULTS: There were five perioperative deaths in the mechanical group and one in the human group (p = 0.2). Late complications in the mechanical group included 4 late deaths, 2 cases of endocarditis, 3 thromboembolic complications, and 10 reoperations on the aortic valve. In the human group, there were no late deaths, 2 reoperations for allograft aortic valve deterioration (both in Marfan's patients), and 1 reoperation for allograft pulmonary valve stenosis. Four-year actuarial survival was 83% in the mechanical group and 98% in the human group (p = 0.02). Four-year actuarial survival free of all valve-related complications was 61% in the mechanical group and 88% in the human group (p = 0.008). CONCLUSIONS: Human valves in children requiring AVR provide superior intermediate-term survival and freedom from valve-related complications compared to mechanical valves. Marfan's syndrome may represent a rare remaining contraindication for human AVR in children.

A detailed histologic analysis of pulmonary arteriovenous malformations in children with cyanotic congenital heart disease.

INTRODUCTION: Pulmonary arteriovenous malformations are a common cause of progressive cyanosis in children after cavopulmonary anastomoses. We analyzed the pulmonary histologic characteristics from children in whom pulmonary arteriovenous malformations developed after procedures that resulted in pulmonary arterial blood flow devoid of hepatic venous effluent. METHODS: We performed routine histologic studies, immunohistochemical staining, and electron microscopic analysis of peripheral lung biopsy specimens from 2 children with angiographically proven pulmonary arteriovenous malformations. Microvessel density was determined with a computer-assisted, morphometric analysis system. RESULTS: Histologic examination demonstrated large, dilated blood vessels ("lakes") and clustered, smaller vessels ("chains") in the pulmonary parenchyma. Microvessel density was significantly greater in these patients than in age-matched controls (P =.01). Immunohistochemistry demonstrated uniform staining for type IV collagen and alpha-smooth muscle actin, weak staining for the endothelial marker CD31 (cluster of differentiation, PECAM-1), and negative staining for proliferating cell nuclear antigen. Electron microscopy revealed endothelial irregularity, a disorganized basement membrane, and increased numbers of collagen and actin filaments beneath the endothelium. CONCLUSIONS: This study represents an attempt to characterize the histologic features of pulmonary arteriovenous malformations in children with congenital heart disease who have pulmonary arterial blood flow devoid of hepatic venous effluent. The histologic correlate of this condition appears to be greatly increased numbers of thin-walled vessels. Immunohistochemistry suggests that the rate of cellular proliferation is not increased in these lesions. The development of these techniques may provide a standardized histologic approach for this condition and aid in understanding its etiology.

Does ductal occlusion with the gianturco coil cause left pulmonary artery and/or descending aorta obstruction?

Thirty-two patients (median age 4.5 years) underwent transcatheter Gianturco coil occlusion of a patent ductus arteriosus. Transthoracic echocardiography was performed the day after coil placement and at intermediate follow-up (median 8.6 months). Echocardiographic results were compared with angiographic and hemodynamic data obtained during catheterization. Two-dimensional (2D) echocardiography performed the day after ductal occlusion displayed evidence of coil protrusion into the left pulmonary artery in 28 of 31 patients (90%) and into the descending aorta in 17 of 29 (59%). However, pulsed Doppler analysis demonstrated normal left pulmonary arterial flow velocities in 28 of 29 patients (97%) and normal descending aortic flow velocities in 26 of 27 (96%). Pulse Doppler results were corroborated by angiographic and hemodynamic catheterization data, which showed no evidence of adjacent vessel obstruction. Peak Doppler velocities among patients with and without 2D echocardiographic left pulmonary artery or descending aorta coil impingement did not differ significantly. The discrepancy between 2D and pulse Doppler findings did not change significantly at intermediate follow-up. Thus, transcatheter occlusion of the patent ductus arteriosus with properly implanted Gianturco coils does not cause significant obstruction to flow in the left pulmonary artery or descending aorta despite frequently misleading 2D echocardiographic images of coil impingement on these vessels.

Tracheal aspirate as a substrate for polymerase chain reaction detection of viral genome in childhood pneumonia and myocarditis.

BACKGROUND: Infectious respiratory disorders are important causes of childhood morbidity and mortality. Viral causes are common and may lead to rapid deterioration, requiring mechanical ventilation; myocardial dysfunction may accompany respiratory decompensation. The etiologic viral diagnosis may be difficult with classic methods. The purpose of this study was to evaluate polymerase chain reaction (PCR) as a diagnostic method for identification of causative agents. METHODS AND RESULTS: PCR was used to amplify sequences of viruses known to cause childhood viral pneumonia and myocarditis. Oligonucleotide primers were designed to amplify specific sequences of DNA virus (adenovirus, cytomegalovirus, herpes simplex virus, and Epstein-Barr virus) and RNA virus (enterovirus, respiratory syncytial virus, influenza A, and influenza B) genomes. Tracheal aspirate samples were obtained from 32 intubated patients and nucleic acid extracted before PCR. PCR results were compared with results of culture, serology, and antigen detection methods when available. In cases of myocarditis (n=7), endomyocardial biopsy samples were analyzed by PCR and compared with tracheal aspirate studies. PCR amplification of viral genome occurred in 18 of 32 samples (56%), with 3 samples PCR positive for 2 viral genomes. Amplified viral sequences included RSV (n=3), enterovirus (n=5), cytomegalovirus (n=4), adenovirus (n=3), herpes simplex virus (n=2), Epstein-Barr virus (n=1), influenza A (n=2), and influenza B (n=1). All 7 cases of myocarditis amplified the same viral genome from heart as found by tracheal aspirate. CONCLUSIONS: PCR is a rapid and sensitive diagnostic tool in cases of viral pneumonia with or without myocarditis, and tracheal aspirate appears to be excellent for analysis.

Echocardiographic hemodynamic and morphometric predictors of survival after two-ventricle repair in infants with critical aortic stenosis.

OBJECTIVES: The purpose of this study was to identify echocardiographic hemodynamic and morphometric factors that would predict which infants with critical aortic stenosis could undergo relief of left ventricular outflow obstruction as opposed to the Norwood procedure. BACKGROUND: Echocardiographic predictors of survival in infants with critical aortic stenosis after two-ventricle repair have been mainly limited to morphometric factors, which have limitations. Echocardiographic hemodynamic predictors of survival in these patients have not previously been studied. METHODS: Doppler color flow mapping and pulsed Doppler techniques were used to obtain hemodynamic measurements of flow in the ascending, transverse and descending aorta, the ductus arteriosus, and across the aortic and mitral valves in infants with critical aortic stenosis. Morphometric measurements of the left heart structures were obtained, and comparisons were made between survivors and nonsurvivors for the hemodynamic and morphometric factors. RESULTS: Twenty-eight infants (mean age 1 +/- .6 days, mean weight 3.6 +/- .6 kg) with critical aortic stenosis were evaluated. Nineteen had a two-ventricle repair initially attempted, and nine had a Norwood operation. Among the patients with a two-ventricle repair, the hemodynamic factors associated with survival after two-ventricle repair included predominant or total antegrade flow in the ascending (p < 0.01) and transverse aorta (p < 0.05). Aortic valve gradient, mitral valve inflow and direction of flow in the ductus arteriosus and descending aorta were unrelated to outcome. The morphometric factors associated with survival after two-ventricle repair included the indexed aortic annulus (p < 0.0002), aortic root (p < 0.003), ascending aorta (p < 0.008) and left ventricular long-axis length (p < 0.01). Left ventricular volume, mass, ejection fraction and mitral valve area were not related to outcome after two-ventricle repair. CONCLUSIONS: In infants with critical aortic stenosis, predominant or total antegrade flow in the ascending and transverse aorta was associated with survival after two-ventricle repair. Determination of a one- versus two-ventricle repair remains a complex issue in infants with critical aortic stenosis. In addition to established morphometric predictors, hemodynamic information on the direction of flow in the aorta may help to define candidates for the Norwood operation.

Risk factors for life-threatening cavopulmonary thrombosis in patients undergoing bidirectional superior cavopulmonary shunt: an exploratory study.

We have observed six patients with life-threatening superior vena caval or pulmonary thrombosis after bidirectional superior cavopulmonary shunt. With the use of a case control study we sought to identify perioperative risk factors for this thrombotic complication. Medical records of six patients with cavopulmonary thrombosis and those of 24 patients in a control group were reviewed to abstract data for potential risk factors. Contingency tables and univariate logistic regression were used to determine associations between various perioperative parameters and occurrence of cavopulmonary thrombosis. Preoperative variables associated with thrombosis included bilateral superior vena cavae, odds ratio: 23, p = 0.02, increased age at surgery (p = 0.05), and female sex (odds ratio: 7, p = 0.05). The McGoon Ratio (index of relative pulmonary artery branch diameter) was inversely related to thrombosis risk (p = 0.08). Two torr increases in mean right atrial (p = 0.08) or ventricular end-diastolic (p = 0.05) pressures were associated with approximately 70% increases in thrombosis risk. Intraoperative prolongation of aortic cross-clamp time related directly to thrombosis risk (p = 0.06). Postoperative variables associated with thrombosis included increased superior vena caval pressure within 12 hours after surgery (odds ratio > or = 10 for 5 torr increase in pressure, p = 0.02) and poor ventricular function (odds ratio: 9, p = 0.06) We conclude that high risk variables for patients undergoing a cavopulmonary shunt include bilateral superior vena cavae, female sex, increasing age, decreased McGoon Ratio, and elevated right atrial and ventricular end-diastolic pressure (before surgery), patients with prolonged aortic cross-clamp time (during surgery), and patients with elevated superior vena caval pressure and poor ventricular function (after surgery).

Patterns of prenatal growth among infants with cardiovascular malformations: possible fetal hemodynamic effects.

This study characterized fetal growth differences among control infants (n= 276) and infants with d-transposition of the great arteries (TGA) (n = 69), tetralogy of Fallot (n = 66), hypoplastic left heart syndrome (n = 51), and coarctation of the aorta (n = 65), thus permitting assessment of competing theories about the relation between these cardiovascular malformations and fetal growth disturbance. Subjects were liveborn singletons without genetic or extra-cardiovascular structural abnormalities sampled from the Baltimore-Washington Infant Study. Multivariate analysis of covariance was performed: birth weight, birth length, newborn head circumference, and two nonlinear functions of these measures were regressed jointly on a diagnostic class variable and covariates. Differences in the vectors of dependent variable means across diagnostic groups were striking (p < 0.0001). Infants with TGA had normal birth weight, but lesser head volume relative to birth weight. Infants with tetralogy of Fallot were smaller in all measured dimensions, but they were shaped normally. Infants with hypoplastic left heart syndrome were smaller in all measured dimensions, and head volume was disproportionately small relative to birth weight. Infants with coarctation of the aorta had lower birth weight, shorter birth length, and greater head volume relative to birth weight. These findings suggest that fetal circulatory abnormalities may predict abnormal patterns of fetal growth.

Factors in the physician practice location puzzle: a survey of New York State residency-trained family physicians.

BACKGROUND: For the past 5 years fewer medical students have selected primary care specialties, and one-third of all physicians have indicated they will move in the next 5 years. These two factors make family physicians one of the most recruited specialties in medicine. METHODS: A questionnaire about practice profiles and factors that have an impact on a physician's location decision was mailed to all physicians who graduated from New York State family medicine residencies between 1970 and 1989. Data from completed responses were analyzed by year of graduation from residency, community size, and whether the responder remained in New York State or chose to locate outside New York State. RESULTS: There were 711 (46 percent) physicians who responded. The number of minorities remained stable at 14 percent during these years, but women graduates increased from 12 percent to 21 percent. The graduates in the 1980s, when compared with those in the 1970s, were more likely to be salaried, make less money, and to believe employment for the physician's spouse to be important in practice location. The 38 percent of responders from communities of fewer than 25,000 were less likely to be salaried, were more likely to practice in a group, worked more hours, offered a broader range of services including obstetrics, made less money, and placed less importance on availability of hospital consultants. Extended family, previous negotiated obligations, and geographic or climate issues were the reasons 64 percent of out-of-state responders gave for leaving New York. Spouse's opinion, hospital consultants, hospital services, colleague interaction, and after-hours coverage were most frequently rated as important factors for family physician practice location. CONCLUSIONS: Factors important in attracting new physicians to a community include the spouse's opinion, institutional and colleague support, and lifestyle issues.

Birth weight and cardiovascular malformations: a population-based study. The Baltimore-Washington Infant Study.

Mean birth weights were evaluated in infants with D-transposition of the great arteries, tetralogy of Fallot, endocardial cushion defect, hypoplastic left heart syndrome, pulmonary stenosis, aortic stenosis, coarctation of the aorta, ventricular septal defect, and atrial septal defect in a population-based case-control study of congenital cardiovascular malformations in residents of Maryland, Washington, D.C., and northern Virginia (1981-1987). Study subjects were liveborn singletons without extracardiac anomalies. After adjustment for potentially confounding maternal, gestational, and infant factors, significant birth weight deficits were found for infants with tetralogy of Fallot, endocardial cushion defect, hypoplastic left heart syndrome, pulmonary stenosis, coarctation of the aorta, ventricular septal defect, and atrial septal defect. After adjustment, infants with these malformations (except coarctation of the aorta and atrial septal defect) were also significantly more likely than were controls to have low birth weight for gestational age. These findings strengthen previous evidence that certain cardiovascular malformations and low birth weight may be causally related.