Abstract 11933: Cardiac and Fibrosis-Related Biomarker Levels Do Not Predict Disease Development in Presymptomatic Phospholamban Cardiomyopathy

Introduction: Phospholamban (PLN) cardiomyopathy is an inherited cardiomyopathy with malignant arrhythmias and/or heart failure due to fibrosis. There is no proven treatment against disease progression. The i-PHORECAST trial investigated whether the antifibrotic properties of eplerenone prevent disease development in presymptomatic mutation carriers using late gadolinium enhancement (LGE) as a measure of cardiac fibrosis. As part of this study, several biomarkers linked to cardiac damage and fibrosis were measured to investigate their prognostic use. Hypothesis: We assessed if biomarkers linked to cardiac damage and fibrosis enable early detection of overt PLN cardiomyopathy. Methods: Presymptomatic PLN mutation carriers (N=84, age 39 [27-50] years, 44% male) were randomized to receive eplerenone or no treatment. Biomarkers (NT-pro-BNP, troponin, TP1NP, GDF-15, and IL-6) were measured from blood samples at baseline (N=84) and after a three year follow up (N=57, age 37 [26-46] years, 49% male). Composite endpoints included changes in LVEDV/RVEDV/LVEF/RVEF, new LGE, QRS voltage, symptoms requiring treatment, ventricular ectopy, and cardiovascular death. Results: No clinically relevant and statistically significant differences between treatment groups, Table 1 . No significant association between baseline biomarker measurements and LVEF decrease or the development of new LGE, Figure 1 . Conclusions: Levels of NT-pro-BNP, troponin, TP1NP, GDF-15, and IL-6 are not associated with development of cardiac fibrosis or left ventricular dysfunction in presymptomatic PLN mutation carriers, thus do not enable early detection of overt PLN cardiomyopathy.