Impact of Cardiac Arrhythmias on Acute Maternal Cardiovascular Outcomes in Pregnancy: A Systematic Review and Meta-Analysis.

Cardiac arrhythmias are prevalent complications in pregnancy, yet their precise association with acute maternal cardiovascular morbidity and mortality remains unclear due to heterogeneous evidence. This systematic review and meta-analysis evaluated the impact of maternal arrhythmias on acute cardiovascular outcomes. We searched Medline, Scopus, and Cochrane databases for observational studies comparing pregnant women with arrhythmias to those without. Random-effects meta-analyses were used to calculate pooled risk ratios (RR) for maternal mortality and major adverse cardiovascular events (MACE). Eleven studies comprising 76,028 pregnancies with arrhythmias and over 82 million controls were included. Analysis of data, primarily derived from large administrative cohorts with low absolute event rates, indicated that arrhythmias were significantly associated with increased all-cause maternal mortality (0.78% vs. 0.01%; RR 31.94; adjusted RR 8.91) and a composite of MACE (2.90% vs. 0.03%; RR 6.48). Supraventricular tachycardia and atrial fibrillation were associated with an increased likelihood of adverse outcomes. Notably, the relative risk of mortality and heart failure in women with arrhythmias versus controls was significantly higher in the general obstetric population around delivery than in women with known structural heart disease, suggesting a "sentinel event" phenomenon. Thromboembolic events were also 15 times more likely in the arrhythmia group. Cardiac arrhythmias during pregnancy are associated with substantial maternal morbidity and mortality. New-onset arrhythmias may warrant comprehensive cardiac evaluation, as they may unmask underlying pathology and precipitate severe hemodynamic compromise, particularly in women without prior cardiac history.