Risk Factors of Cardiac Complications in Pregnant Women with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a common inherited genetic cardiac disease during pregnancy. Studies of risk factors are of great significance for maternal and fetal outcomes. The aim of the study was to identify predictive risk factors for cardiac complications in pregnant women with HCM. One hundred patients with HCM who delivered at the Shanghai obstetrical cardiology intensive care center between January 2000 and December 2022 were retrospectively reviewed. A logistic regression model was used to identify independent risk factors for cardiac complications. Twenty-one cases were obstructive HCM (21%), 16 with cardiac function grade I and 5 with grade II; 79 cases were non-obstructive HCM (79%), 67 with cardiac function grade I, 11 with grade II, and 1 with grade III. Ninety-one cases had abnormal electrocardiogram (ECG) (91%), mainly with ST-T changes (77%). The average interventricular septum was 19.39 ± 6.13 mm by echocardiography (21.75 ± 5.86 mm for obstructive HCM and 18.73 ± 6.08 mm for non-obstructive HCM). The main cardiac complications were maternal death (n = 2, 2%), heart failure (n = 7, 7%), and sustained ventricular tachyarrhythmia (n = 1, 1%). Cardiac complications occur commonly during the third trimester and postpartum period. Three independent risk factors to predict cardiac complications in pregnant women with HCM were obstructive HCM (P = 0.036), New York Heart Association (NYHA) class ≥II (P = 0.022), and previous history of syncope (P = 0.037). HCM increases the risk of maternal death, heart failure, and malignant arrhythmia. More attention should be given to risk assessment and pregnancy management. Early detection of risk factors can reduce the incidence of maternal mortality and cardiac complications.