Prospective Pakistan Registry of Echocardiographic Screening in Asymptomatic Pregnant Women.

Background: Cardiovascular diseases are the primary cause of nonobstetric morbidity and mortality in pregnant women worldwide. Pakistan's high maternal and neonatal mortality rates underscore the need for effective screening protocols to detect cardiovascular diseases during pregnancy. Objectives: The objective of this study was to assess the prevalence and factors associated with structural heart disease among pregnant women without active cardiorespiratory symptoms (no symptoms or symptoms attributed to pregnancy) attending routine antenatal appointments. Methods: Obstetric patients without known heart disease attending routine antenatal visits were enrolled between February 2023 and March 2024. All patients had a standardized limited transthoracic echocardiogram. Left ventricular ejection fraction was quantified using biplane Simpson's method. Multivariable binary logistic regression analysis was performed to identify determinants of left ventricular systolic dysfunction (LVSD). Results: We enrolled 15,068 pregnant women (mean age 26.2 ± 5.1 years) of which 32.4% were primiparous and 0.9% had multifetal gestations. Screening occurred in the first trimester in 1.6% of patients and in the third trimester in 69.4%. structural heart disease was observed in 569 patients (3.8%): 338 (2.2%) with LVSD, 188 (1.2%) with valvular heart disease and 68 (0.5%) with congenital heart disease. Logistic regression analysis identified pregnancy-induced hypertension, tachycardia, and valvular heart disease as factors associated with LVSD. Conclusions: In a large cohort of pregnant women in Pakistan undergoing routine antenatal echocardiographic screening, almost 4% had structural heart disease. Notably, 2.2% of women had LVSD without active cardiorespiratory symptoms. In select populations, screening can help facilitate early cardiac diagnosis and referral to cardio-obstetrics care. (Prospective Pakistan Registry of Echocardiographic Screening in Asymptomatic Pregnant Women [PRESAP]; NCT06004544).