Initial Right Ventricular Dysfunction Severity Identifies Severe Peripartum Cardiomyopathy Phenotype With Worse Early and Overall Outcomes: A 24‐Year Cohort Study

BACKGROUND: Outcomes in peripartum cardiomyopathy (PPCM) vary. We sought to determine whether severity of left or right ventricular dysfunction (RVD) at PPCM diagnosis differentially associates with adverse outcomes. METHODS AND RESULTS: We conducted a single‐center retrospective cohort study of 53 patients with PPCM. The primary outcome was a composite of left ventricular assist device implantation, cardiac transplantation, or death. We used Kaplan‐Meier curves to examine event‐free survival and Cox proportional hazards models to examine associations of left ventricular (LV) ejection fraction <30%, LV end‐diastolic diameter ≥60 mm, and moderate‐to‐severe RVD at PPCM diagnosis with the primary outcome. Median (interquartile range) follow‐up time was 3.6 (1.4–7.3) years. Seventeen patients (32%) experienced the primary outcome, of whom 11 had moderate‐to‐severe RVD at time of PPCM diagnosis. Overall event‐free survival differed by initial RVD severity and LV ejection fraction <30%, but not by LV end‐diastolic diameter ≥60 mm. In univariable analyses, LV ejection fraction <30% and moderate‐to‐severe RVD were associated with the outcome (hazard ratios [95% confidence intervals] of 4.85 [1.11–21.3] and 4.26 [1.47–11.6], respectively). In a multivariable model with LV ejection fraction <30%, LV end‐diastolic diameter ≥60 mm, and moderate‐to‐severe RVD, only moderate‐to‐severe RVD was independently associated with the outcome (hazard ratio [95% confidence interval], 3.21 [1.13–9.10]). Although most outcomes occurred within the first year, nearly a third occurred years after PPCM diagnosis. CONCLUSIONS: Initial moderate‐to‐severe RVD is associated with a more advanced cardiomyopathy phenotype and increased risk of adverse outcomes in PPCM, within and beyond the first year of diagnosis. By identifying a worse PPCM phenotype, initial moderate‐to‐severe RVD may prompt earlier consideration of advanced heart replacement therapies.