Significance of cardiac defects in the developing fetus: a study of spontaneous abortuses.

Abstract

We investigated the impact of heart defects on the developing human fetus by examining 412 hearts from consecutive spontaneous abortuses. In each case, the cardiac morphology was correlated with the autopsy findings and the karyotype (unavailable in 115 hearts not successfully cultured). Of the 412 hearts, 10 (2.4%) contained structural defects (six ventricular septal defects, one atrial septal defect with ventricular septal defect, and one each coarctation, atrioventricular septal defect, and tetralogy of Fallot). Only one of 10 had major extracardiac malformations. Of the 277 fetuses with normal karyotype, three (1. 1%) had heart defects. Of the 20 fetuses with abnormal karyotype, four (20%) had heart defects. In the remaining three fetuses with heart defects, the karyotype was not obtained. Thus (1) 57% of spontaneous abortuses with congenital heart defects contained major chromosomal abnormalities, (2) the spectrum of heart defects among spontaneous abortuses was similar to that among liveborns, and (3) since the prevalence of heart defects among fetuses without other major abnormalities was similar to that among liveborns, heart defects alone may not jeopardize the survival of a developing fetus. Circulation 72, No. 6, 1232No. 6, -1236No. 6, , 1985 THE SIGNIFICANCE of heart defects in the developing fetus is uncertain. Major structural malformations of the heart that cause shunting and/or obstruction could be detrimental to the fetus. Studies have documented a higher prevalence of heart defects among stillborn infants than among liveborns. 1-3 However, it has never been clear from such studies whether the heart defect per se was responsible for death. In this regard, physiologic studies performed in animal preparations suggest that cardiac defects have little effect in utero.4 Thus, cardiac defects may be a part of some other abnormal developmental process that results in death of the fetus.We investigated the impact of heart defects on the developing human fetus by examining hearts from consecutive spontaneous abortuses. Analysis of the products of conception from spontaneous abortions provides an efficient means of evaluating the importance of morphologic and chromosomal anomalies to the survival of the fetus.5 We correlated the cardiac pathology in each case with the karyotype and pathology manifest in the remainder of the fetus. Our objectives in this study were (1) to determine the prevalence and nature of cardiac defects among spontaneously aborted fetuses, and (2) to develop insight into the significance of these defects in the developing fetus. Materials and methodsHearts examined in this study were obtained from a large epidemiology-cytogenetic-pathology study of consecutive spontaneous abortions identified at three New York City hospitals between 1976 and 1983. Approximately 4000 specimens were examined as a part of the larger study. However, because most products of conception from spontaneous abortions do not contain an organized fetus6 and some hearts are not large enough to study, o...

Fetal Pathology in Second-Trimester Miscarriages

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Fetal morphological features and abnormalities associated with equine early pregnancy loss

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