Peripartum cardiomyopathy: an often mislabelled diagnosis

Abstract

Background: "Peripartum cardiomyopathy" (PPCM) is a diagnosis of exclusion, often misused to describe all presentations of left ventricular dysfunction or decompensation peripartum. Methodology: We retrospectively reviewed patients diagnosed with PPCM at our centre, analysing their clinical history, imaging, and maternal-fetal outcomes. Result(s): Sixty-two patients were identified, aged 22 to 47 years (mean 33) at diagnosis. Sixty-eight percent (68%) were para 1 or 2, 36% had more than 3 children. Ethnicity distribution is presented in Picture 1. Thirty-three percent (33%) were subsequently found to have a family history of cardiomyopathy/genetic mutation. Blood pressure data showed 37% of women were hypertensive at presentation, 18% pre-eclamptic, 30% had had significant post-partum haemorrhage (PPH). There were no cases of extreme or very pre-term births, 44% were moderate to late preterm (32 - 36+6 weeks gestation) and 56% were born at term. Timing of diagnosis was: 27% during pregnancy, 25% peri delivery, 29% within 4 weeks postpartum, and 17% after 4 weeks. At presentation, 50% had an LVEF 50% (Picture 2). One patient died 9 years after diagnosis (EF 19%, no recovery). Forty-six percent (46%) of patients recovered to LVEF >55%, and 90% with moderate-severe LV dysfunction showed at least a 10% improvement. The mean LVEF for patients with initial EF <45% improved from 28% to 48%. Sixty-three percent (63%) of patients remained on heart failure therapy at follow-up (range 1-14 years, mean 5). Ninety-eight (98%) of patients have subsequently had preconceptual counselling with a consultant obstetrician and a cardiologist with expertise in maternal cardiology. Likely diagnosis based on history and imaging were: PPCM (16%), preeclampsia/severe hypertension related (10%), familial DCM (33%), 5% ectopic atrial arrhythmia (5%), myocarditis (5%), takotsubo (5), multifactorial (7%), mild LV impairment decompensation (17%). Conclusion(s): The diagnosis of PPCM is complex and often misapplied. Thorough history, investigation and accurate diagnosis is essential for future management and preconceptual counselling. Obstetric and neonatal outcome data is reassuring with regards to rates of pre-term birth. Further research is required to study the association and impact of pregnancy hypertensive disorders and LV dysfunction. This study highlights how the literature, especially coding-based studies, may represent a broader group rather than true PPCM cases.