Infants with single ventricle: A population‐based epidemiological study

Background Single ventricle, a rare congenital cardiac defect, often occurs as part of a complex group of cardiovascular abnormalities. Little is known of its epidemiologic associations. Methods Using data from the Baltimore‐Washington Infant Study [BWIS], (1981–89), a population based case‐control study of cardiovascular malformations, infants with single ventricle were evaluated with respect to infant and family characteristics and maternal and paternal exposures. The cases were analyzed according to presence/absence of abnormal cardio‐visceral situs. Controls were 3,572 infants without heart defects randomly selected from the regional cohort of live births. Odds ratios and 95% confidence intervals were used as measures of association. Results Single ventricle occurred in 1.25% of infants with congenital cardiovascular defects in the BWIS. Fifty‐five infants had single ventricle. In 48 families (87.3%) the parents were interviewed. Thirty‐three infants had normal situs and 15 had abnormal situs. Paternal alcohol consumption (OR = 2.0, 95% CI 1.1–3.9) and paternal cigarette smoking (OR = 2.4, 95% CI 1.1–5.1) were associated with all cases of single ventricle. These associations were even stronger in the subset of infants with abnormal situs. Maternal history of a previous induced abortion was also associated with infants born with abnormal situs (OR = 3.2, 95% CI 1.1–11.5). Paternal marijuana use was associated with cases of single ventricle in normal situs (OR = 2.2, 95% CI 1.0–5.2). Conclusions Potential risk factors included paternal smoking and alcohol consumption, highlighting the need for future studies to consider environmental factors in the pathogenesis of this cardiac defect. Teratology 65:106–115, 2002.