Abstract 4186: Magnetic Resonance Late Enhancement in Dilated Cardiomyopathy is Related with Complex Ventricular Arrhythmias

Abstract

Late enhancement (LE) by cardiovascular magnetic resonance (CMR) has been found in about two-thirds of patients with dilated cardiomyopathy (DCM). However, the functional significance of this finding is not well established. The aim of this study was to assess, in patients (pts) with DCM, the relationship of LE with complex ventricular arrhythmias. Methods: 38 consecutive pts (44±8 years-old, 26 men) with DCM were included, after exclusion of ischemic heart disease by coronary angiography and secondary cardiomyopathies by clinical and laboratory investigation. Functional class and plasmatic NT-pro-BNP were assessed. All underwent CMR: short-axis SSFP encompassing all LV; LV volumes and ejection fraction (EF) were obtained; LE (segmented inversion-recovery fast gradient-echo sequence), 10 –15 mn after 0.2mmol/kg of Gd-DTPA acquired in 2, 3, 4-chambers and short-axis views; LE was classified in subendocardial or midwall and quantified using plannimetry of LE contours, 6SD from remote myocardium; a fibrosis index was obtained from LE mass/myocardial mass. All underwent 24 H Holter monitoring, less than one month from CMR, and the number of ventricular arrhythmias (pairs, triplets or ventricular tachycardia) assessed. Results: 22 pts were in NYHA class II and 17 in class III. Mean NT-pro-BNP was 512 ± 134 pg/ml, LV end-diastolic volume was 161±35mL/m2, mean EF was 31 ± 8%. LE was found in 26 patients (68%) and was always present in the midwall, involving a mean of 8 segments per patient (range 3–13); septal and anterior walls were the most frequently involved. There were repetitive ventricular arrhythmias in 29 pts. In comparison with pts without LE, pts with LE had higher NT-pro-BNP (917 vs 431 pg/ml, p=0.001), larger LV end-diastolic volumes (173 vs 143ml/m2, p=0.001) and lower EF (26% vs35%, p=0.001) and higher number of complex ventricular arrhythmias (p=0,0004). No relationship was found between the fibrosis index and the number of arrhythmias. Using multivariate analysis, the presence of LE was an independent predictor of ventricular arrhythmias (/p=0.002). Conclusion: In patients with DCM, LE is significantly associated and an independent predictor of complex ventricular arrhythmias among LV volumes, ejection fraction and NT-pro-BNP,