Sex-Related Differences and Influence of Pregnancy in Transposition of Great Arteries With Systemic Right Ventricle

Background There is a paucity of data regarding sex-related differences on cardiac outcomes in the context of transposition of the great arteries (TGA) with a systemic right ventricle and biventricular physiology (sRV-biV). Moreover, the long-term impact of pregnancy on cardiac outcomes remains unknown. Objectives The purpose of this study was to identify sex-related differences and the influence of pregnancy on cardiac outcomes in TGA sRV-biV population. Methods A retrospective cohort study was conducted on 213 adults with TGA sRV-biV, 82 (38.4%) women, age 42.6 ± 12.8 years, with a median follow-up of 16 years. Cardiac events, interventions, last follow-up sRV-biV dysfunction, and heart failure (HF) medications were compared between men vs women, and women with vs without pregnancies resulting in live births. Results Women had a lower incidence of nonsustained ventricular tachycardia (HR: 1.80; 95% CI: 1.04-3.09, P = 0.035) and nonsignificantly fewer HF-related hospitalizations than men (HR: 2.10; 95% CI: 0.95-4.67, P = 0.069) in univariable analysis. At the last follow-up, women had a lower prevalence of moderate to severe sRV-biV dysfunction than men (P < 0.001) and were less frequently prescribed HF therapy. Women had fewer implantable cardioverter-defibrillators for primary prevention than men (P = 0.016), with no difference for secondary prevention. Women who had pregnancies resulting in live births (N = 47), had a high prevalence of cardiac events in the 15 (IQR: 9-28) years following pregnancy with no significant differences with those without (N = 32) pregnancies. Conclusions Women with a sRV-biV have fewer adverse cardiovascular events than men. Due to sRV-biV, pregnancy remains with high maternal risk but is not associated with worse long-term cardiac outcomes under rigorous multidisciplinary cardio-obstetrical care.