TRENDS AND OUTCOMES AFTER PRENATAL-DIAGNOSIS OF CONGENITAL CARDIAC-MALFORMATIONS BY FETAL ECHOCARDIOGRAPHY IN A WELL-DEFINED BIRTH POPULATION, ATLANTA, GEORGIA, 1990-1994

Objectives. In this study we used a population-based approach to asses s the impact of fetal echocardiography on a well defined birth populat ion with nearly complete ascertainment of cardiac defects. Background. Although fetal echocardiography is being used more frequently in the prenatal diagnosis of congenital cardiac malformations, its impact on the diagnosis and surveillance of cardiac defects has not been describ ed in defined populations. Methods. All stillborn and live-born infant s with diagnosed cardiac defects and whose mothers resided in the metr opolitan Atlanta area from January 1990 through December 1994 were asc ertained through an established birth defects surveillance system. All fetuses with cardiac defects diagnosed prenatally by a pediatric card iologist were identified from clinical records. The spectrum of cardia c defects, diagnostic trends and adverse fetal outcomes were described . Results. We identified 1,589 infants with congenital cardiac malform ations, for a live-birth prevalence rate of 8.1/1,000 (95% confidence interval [CI] 7.8 to 8.6). Overall, 97 (6.1%) of these cases of cardia c malformations were diagnosed prenatally. The proportion of cardiac d efects diagnosed prenatally rose from 2.6% in 1990 to 12.7% in 1994, a nearly fivefold increase. The proportion of cardiac defects diagnosed prenatally during the study varied by the type of defect, from a low of 4.7% for atrial septal defects to a high of 28% for hypoplastic lef t heart syndrome. Prenatally diagnosed cardiac malformations were asso ciated,vith a high incidence of infant mortality (30.9%, 95% CI 2.4 to 5.4) and fetal wastage (17.5%, 95% CI 6.2 to 11.3). Conclusions. Thes e data show that fetal echocardiography is being used increasingly in the prenatal diagnosis of congenital cardiac malformations in metropol itan Atlanta. Few pregnancy terminations were reported as a result of such diagnoses. However, the study had limited power (10%) to detect a meaningful decrease in birth prevalence rates for congenital heart di sease. In addition, survival of infants was not improved after prenata l diagnosis with fetal echocardiography. (C) 1996 by the American Coll ege of Cardiology