Abstract 12664: Comprehensive Histological Analysis of Endomyocardial Biopsy and T1 Mapping for Predicting Left Ventricular Reverse Remodeling in Patients with Recent-Onset Dilated Cardiomyopathy

Abstract

Listen

Translate article

Background: Cardiomyocyte injury is a key pathological pathway in the progression of heart failure that predicts a poor prognosis; therefore, combined assessment of myocardial fibrosis and cardiomyocyte DNA damage from endomyocardial biopsy (EMB) samples may be of great importance. Meanwhile, cardiovascular magnetic resonance (CMR) native T1 reflects a composite of both intra- and extracellular compartments in the whole myocardium. We sought to assess the performance of native T1 mapping and EMB results to predict left ventricular reverse remodeling (LVRR) in recent-onset dilated cardiomyopathy (DCM). Methods: A total of 29 patients with DCM underwent cine CMR and triple-slice T1 mapping using the MOLLI sequence at 3T, and EMB before receiving guideline-directed medical therapy. Poly ADP-ribose (PAR) nuclear and sirius-red staining were used for quantification of DNA damage and collagen volume fraction (CVF), respectively. LVRR was defined as an increase in LV ejection fraction of ≥10% to the final value of >35%, accompanied by a decrease in LV end-diastolic volume ≥10% at the follow-up CMR. Results: Fifteen patients (52%) achieved LVRR. The mean native T1, histological CVF, and proportion of PAR-positive nuclei were 1376 ± 55 ms, 0.13 ± 0.05, 25 ± 15%, respectively. Native T1 correlated well with CVF (p=0.004) and trended to be higher in DCM patients with increased DNA damage (p=0.17). There was no significant association between CVF and %PAR-positive nuclei. Native T1 <1400 ms provided 86% sensitivity and 67% specificity, with the C-statistic of 0.82 (95% CI 0.67-0.98) for predicting LVRR. By contrast, C-statistic of %PAR nuclei, CVF, and combined assessment of %PAR nuclei and CVF were 0.59, 0.61 and 0.66, respectively. Conclusion: CMR T1 mapping may be a promising strategy for noninvasive biopsy of the whole heart and provide a better prediction of LVRR in recent-onset DCM than comprehensive histological analysis of EMB.