The effect of eplerenone on the disease onset and progression of phospholamban cardiomyopathy in presymptomatic mutation carriers: results of the i-PHORECAST trial

Abstract

Abstract Background A pathogenic variant in the gene encoding phospholamban (PLN; p.Arg14del) may cause cardiomyopathy, the pathophysiologic hallmark of which is cardiac fibrosis that may cause malignant ventricular arrhythmias and severe heart failure. There is no evidence-based therapy to modify disease progression in presymptomatic pathogenic variant carriers. Eplerenone is a selective mineralocorticoid receptor antagonist with established antifibrotic properties, and may be a potentially interesting treatment in PLN p.Arg14del mutation carriers. Purpose To investigate if preventive therapy with eplerenone attenuates disease onset and progression in PLN cardiomyopathy. Methods 84 presymptomatic PLN p.Arg14del mutation carriers (median age 39 [27–50] years, 44% males) were randomized 1:1 to receive eplerenone (50mg once daily) or no treatment, and endpoints were adjudicated in a blinded fashion (PROBE design). Baseline values were acquired including demographics, cardiac magnetic resonance imaging (CMR) parameters (ventricular volumes, systolic function, late gadolinium enhancement (LGE)), and electrocardiographic parameters (QRS voltages and ventricular ectopy per 24 hour). Subjects were re-evaluated every year and CMR was performed at baseline and after three years. The composite endpoint included LVEDV/RVEDV increase (>10%), LVEF/RVEF decrease (5%), newly developed LGE on CMR, increase in ventricular ectopy (>100% PVCs/24h if >1000 PVCs/24h), decrease in QRS voltage (>25%), non-sustained ventricular tachycardia, symptoms or arrhythmias necessitating treatment, and cardiovascular death. Results Two out of 84 subjects (2%) were lost to follow up. 49 out of 82 remaining subjects (60%) reached the composite end point, 25 (60%) in the control group, 24 (60%) in the treatment group (p=0.825). There was no significant difference between the groups when considering the individual end points, see Table 1. Baseline and follow up CMR was performed on 76 subjects, 39 in the control group, 37 in the treatment group. In total there were 10 (13%) cases of newly developed LGE, 6 (18%) in the control group, 4 (12%) in the treatment group (p=0.556), see Figure 1. Conclusions Eplerenone did not significantly attenuate disease onset and progression in presymptomatic PLN p.Arg14del mutation carriers. There was no significant difference in new incidence of LGE between the treatment and control groups. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was financially supported by the Netherlands Cardiovascular Research Initiative, an initiative supported by the Dutch Heart Foundation (The Hague, Netherlands).