Higher Relaxin-2 Levels Lead to Better Myocardial Recovery in Paripartum Cardiomyopathy

Peripartum cardiomyopathy patients had better recovery with higher relaxin-2 levels, but had increased adverse events with higher fms-like tyrosine kinase 1.

Women with a recent peripartum cardiomyopayhy (PPCM) diagnosis who had higher relaxin-2 levels soon after delivery had better myocardial recovery at 2 months, according to data published in the Journal of the American College of Cardiology.

Researchers also observed higher soluble fms-like tyrosine kinase 1 (sFlt1) levels were associated with increased severe symptoms and major adverse clinical events.

PPCM is an uncommon disorder of which little is known. According to previous studies, angiogenic imbalance may contribute to its pathophysiology. In the current study, researchers sought to determine the association between vascular hormones with myocardial recovery and clinical outcomes.

“Recently, vascular biomarkers have been proposed to play a role in the development of PPCM,” they wrote. “In this cohort, elevated relaxin-2 was associated with early myocardial recovery and elevated sFlt1 with adverse clinical outcomes. These findings support the idea that vascular homeostasis may play a role in PPCM. These mediators may provide prognostic information and future targets for therapy in PPCM.”

Researchers obtained serum at baseline and analyzed samples for relaxin-2, prolactin, sFlt1, and vascular endothelial growth factor (VEGF) of 98 patients (mean age: 30 ± 6 years) with newly diagnosed PPCM from the IPAC (Investigation in Pregnancy Associated with Cardiomyopathy) study. Left ventricular ejection fraction (LVEF; mean LVEF at baseline: 0.35 ± 0.09) was also assessed at 2, 6, and 12 months using echocardiography.

The results showed elevated levels of relaxin-2, prolactin, and sFlt1 in women presenting with PPCM early postpartum. However, these levels declined rapidly with more time between delivery and presentation.

Higher relaxin-2 was associated with smaller left ventricular systolic diameter (P=.006) and higher LVEF at 2 months (P=.01). The results were particularly evident in women presenting soon after delivery (P=.02). No relationship was observed between myocardial recovery and prolactin, sFlt1, or VEGF levels. Researchers noted that sFlt1 levels were higher in women with higher New York Heart Association functional class (P=.01) and adverse clinical events (P=.004).

“Support for a vascular component to the pathophysiology of PPCM highlights the need for further study of vascular biomarkers in this disorder,” the authors noted. “Whether these agents can serve as prognostic indicators in patients with PPCM needs to be determined.”

Reference

Damp J, Givertz MM, Semigran M, et al. Relaxin-2 and soluble Flt1 levels in peripartum cardiomyopathy: results of the multicenter IPAC study. JACC Heart Fail. 2016; doi: 10.1016/j.jchf.2016.01.004.