Abstract 12915: Reduced Fractional Shortening of Right Ventricular Outflow Tract is Associated with Adverse Outcome in Patients with Left Ventricular Dysfunction

Abstract

Background: Recent studies have shown the significance of right ventricular (RV) function on the outcome in patients with left ventricular dysfunction (LVSD). However, global assessment of RV remains to be determined by echocardiogram because of its complex geometry. This study assessed to validate the RV outflow tract fractional shortening (RVOT-FS) in evaluation of RV function and prognostic value in patients with LVSD.

Methods and Results: Eighty-one patients (62±17 years, mean±SD, male 79%) with reduced LV ejection fraction (LVEF) (≤40%) were included in this study. Two-dimensional echocardiogram of the parasternal short axis view was obtained at the level of the aortic root, and RVOT-FS was calculated as the ratio of end-diastole minus end-systole dimension to end-diastole dimension. RVOT-FS ranged from 0.04 to 0.8 (0.3±0.2, mean±SD) and co-efficient of variation in the two observers was 1.9 ± 4.5 (mean ± SD). RVOT-FS was significantly correlated with LVEF (r=0.33, p=0.0028), RV cavity fractional area change (RVFAC) (r=0.37, p=0.0008) and brain natriuretic peptide (BNP) (r=-0.38, p=0.0005), but not with pulmonary artery systolic pressure (PASP) (r=-0.21, p=0.096). In addition, prognosis including cardiac death, required cardiac transplantation or re-hospitalization due to worsening heart failure was determined by RVOT-FS (p=0.04), but not by LVEF (p=0.082), RVFAC (p=0.06), PASP (p=0.76) or BNP (p=0.10). During a median follow-up period of 295 days (1 to 1694 days), patients with RVOT-FS≥0.2 showed higher event-free ratio than those with RVOT-FS<0.2 by Kaplan-Meier analysis (Log-rank test, p=0.015).

Conclusion: Our data suggests that RVOT-FS is a convenient and reproducible parameter to reflect the severity of RV function in patients with LVSD. In addition, decrease in RVOT-FS might provide adverse predictive value in such a patient population.