Pregnancy in patients with prosthetic heart valves: the effects of anticoagulation on mother, fetus, and neonate.

Maternal and fetal complications in a consecutive series of 60 pregnancies in 49 patients with prosthetic heart valves were prospectively evaluated. Group 1 consisted of 40 pregnancies in 31 patients who were taking oral anticoagulants. No oral anticoagulation was used in 20 pregnancies in 19 patients (group 2). In group 1 there were three instances of acute valvular thrombosis during the 35 pregnancies in patients with mechanical prostheses, with two maternal deaths. There were two episodes of cerebral embolism, one in group 1 and one in group 2. Patients with isolated aortic valve replacement had fewer maternal complications (2 of 13) than patients with isolated mitral valve replacement (15 of 42) without statistical significance. Severe bioprosthesis dysfunction occurred in 4 of 25 pregnancies (one rupture and three stenosis) with two maternal deaths, one in the puerperium and the other in the postoperative period of cardiac surgery during pregnancy. When analyzing obstetric events we observed seven spontaneous abortions and one hydatidiform mole. All spontaneous abortions occurred in group 1. The incidences of prematurity and low birth weight were significantly higher in group 1 than in group 2 (46.6% vs 10.5%, p less than 0.05, and 50% vs 10.5%, p less than 0.05, respectively). Moreover, there was a significant association between prematurity and the mother's New York Heart Association functional class (61.5% in classes III and IV vs 22.2% in classes I and II, p less than 0.05). There were five neonatal deaths, all in group 1 (p = NS vs group 2). Three infants had warfarin-related congenital defects.(ABSTRACT TRUNCATED AT 250 WORDS)