Abstract 9676: Additive Prognostic Value of Diastolic Dysfunction and Coronary Flow Reserve in Non-Ischemic Dilated Cardiomyopathy

Abstract

Background. Coronary flow reserve (CFR) on left anterior descending (LAD) can be reduced in non-ischemic dilated cardiomyopathy (DCM). Aim of the study was to assess the additive prognostic value of CFR in LAD and resting severe diastolic dysfunction to identify responders to CRT. Methods. One hundred twenty-nine DCM patients (pts, 87 men, 62±12 years, ejection fraction: 33±7%) underwent dipyridamole (0.84 mg/kg in 6′) stress echo. CFR was defined as the ratio between maximal vasodilation and rest peak diastolic flow velocity in LAD, and diastolic dysfunction as the presence of resting irreversible restrictive transmitral pattern. Results. We divided DCM pts in 4 groups, according to normal (>2, 56 pts) or abnormal (≤2, 73 pts) CFR on LAD and absence (88 pts) or presence (41 pts) of restrictive transmitral pattern. In pts with abnormal CFR on LAD, the additional presence of restrictive patterns was associated to lower ejection fraction at rest (26±5% vs 31±7% p=.007) and at peak stress (30±5% vs 36±8% p=.03) and larger end-systolic volume at rest (149±55 ml vs 185±48, p=.030). During median follow-up of 30 months, 19 deaths, and 33 cardiac adverse events. Abnormal CFR on LAD and diastolic dysfunction were associated with poorer event-free survival (Log Rank: 33.1, p<0.0001, Figure), with additive negative prognostic value in pts with CFR on LAD <2 and the presence of restrictive pattern. Conclusions. In DCM patients with reduced CFR left anterior descending territory during vasodilator stress, the associate presence of restrictive transmitral pattern is an additive independent prognostic marker of bad prognosis.