Background Maternal placental syndromes (MPS)—gestational hypertension, pre-eclampsia and placental abruption/infarction—are more prevalent in women with features of the metabolic syndrome (MetSyn). Both MPS and the MetSyn predispose to left ventricular impairment and sympathetic dominance after delivery. Whether this translates into a higher risk of heart failure (HF) and cardiac dysrhythmias is not known.

Objective To determine the risk of new onset of HF and dysrhythmias among women after a prior MPS-affected pregnancy.

Methods A retrospective cohort study was carried out of 1 130 764 individual women with a delivery in Ontario between 1992 and 2009, excluding those with cardiac or thyroid disease 1 year before delivery. The risk of a composite outcome of a hospitalisation for HF or an atrial or ventricular dysrhythmia was compared in women with and without MPS, starting 1 year after delivery.

Results 75 242 individuals (6.7%) experienced a MPS. After a median duration of 7.8 years, the composite outcome occurred in 148 women with MPS (2.54 per 10 000 person-years) and 1062 women without MPS (1.28 per 10 000 person-years) (crude HR=2.00, 95% CI 1.68 to 2.38). The mean age at composite outcome was 37.8 years. The HR was 1.61 (95% CI 1.35 to 1.91) after adjustment for demographic characteristics, diabetes, obesity, dyslipidaemia and drug dependence or tobacco use, as well as coronary artery disease or thyroid disease >1 year after delivery. The adjusted HRs were minimally reduced by further adjusting for chronic hypertension (1.51, 95% CI 1.26 to 1.80) and were higher in women with MPS plus preterm delivery and poor fetal growth (2.42, 95% CI 1.25 to 4.67).

Conclusions Women with MPS are at higher risk of premature HF and dysrhythmias, especially when perinatal morbidity is present.