Maternal complete heart block in pregnancy: A systematic review and meta-analysis.

Background: Complete heart block (CHB) is an uncommon bradyarrhythmia complicating pregnancy, posing challenges to the treating team. Objective: To evaluate the maternal outcomes, other cardiac complications, and pregnancy outcomes among pregnant women with CHB and compare these outcomes among those managed with and without pacing. Methods: We searched two databases, i.e., MEDLINE and EMBASE, for studies reporting outcomes in pregnancies complicated by CHB. The bibliography of relevant articles was examined to identify additional articles. Maternal and perinatal outcomes, including obstetric and cardiac complications, were extracted. Using the random-effects model, pooled estimates of various outcomes are reported as percentages with 95% confidence intervals (CIs). Results: A total of 294 pregnancies among 220 women with CHB, identified from 12 studies, were included in the analysis. Two-thirds had either temporary or permanent pacing during pregnancy. Arrhythmias other than CHB were the most common cardiac complications noted (2.7%, 95% CI: 0.9%-4.5%). Lead-related complications, such as lead migration (1.6%, 95% CI: 0.1%-3.0%), were uncommon. One maternal death was reported among the included studies, during the postpartum period in an asymptomatic mother who did not have pacing. Low birth weight was the most common complication (43.1%, 95% CI: 17% - 67%) in the studies reporting neonatal outcomes. Conclusion: Pregnancies complicated with CHB have low rates of adverse maternal and fetal/neonatal outcomes under multidisciplinary care. The outcomes were similar among those with and without pacemakers, suggesting that women can cope with the physiological changes of pregnancy even without pacing.