The Correlation between Peripartum Cardiomyopathy and Autoantibodies against Cardiovascular Receptors

BACKGROUND: Peripartum cardiomyopathy (PPCM) is characterized by left ventricular systolic dysfunction and heart failure. However, its pathogenesis is not clear. Our preliminary study revealed that autoantibodies against β(1)-adrenergic receptors (β(1)R-AABs) and M(2)-muscarinic receptors (M(2)R-AABs) participated in heart failure regardless of primary heart disease. Whether β(1)R-AABs and M(2)R-AABs participate in the pathogenesis of PPCM is still unknown. METHODS: Totally 37 diagnosed PPCM patients and 36 normal pregnant women were enrolled in this study. Clinical assessment and 2-dimensional echocardiographic studies as well as the measurement of β(1)R-AABs or M(2)R-AABs by enzyme linked immunosorbent assay (ELISA) were performed. RESULTS: The positive rates for β(1)R-AABs and M(2)R-AABs were 59.5% (22/37) and 45.9% (17/37) in PPCM patients, and 19.4% (7/36) (P<0.001) and 16.67% (6/36) (P<0.001) in normal pregnant women, respectively. Both β(1)R-AABs and M(2)R-AABs had a positive correlation with serum expression level of NT-proBNP, left ventricular dimension and NYHA FC (rs: 0.496–0.892, P<0.01). In addition, a negative correlation between the activity of β(1)R-AABs and M(2)R-AABs and LVEF, LVFS was observed (rs: −0.488–0.568, P<0.01). Moreover, autoantibodies against cardiovascular receptors increased the risk of the onset of PPCM (OR = 18.786, 95% confidence interval 1.926–183.262, P = 0.012). CONCLUSIONS: The β(1)R-AABs and M(2)R-AABs reveal a significant elevation and are correlated with the increased left ventricular dimension and worse cardiac contraction function. The autoantibodies of cardiovascular receptors are independent risk factors for the onset of PPCM.