112 Importance of ventricular longitudinal function in chronic heart failure

Abstract

Despite its immediate relevance, cardio-pulmonary exercise testing (CPET) is infrequently performed in presence of chronic heart failure (CHF). Previous studies of patients suffering from CHF have found a closer correlation between exercise capacity and measurements of diastolic than systolic ventricular function. We examined the correlation between echocardiographic measurements and a) results of CPET and b) cardiovascular prognosis. We performed resting two-dimensional echocardiograms and CPET in 140 patients with CHF (mean age = 61 ± 13 years, 111 men). The underlying heart disease was ischemic in 48 patients. They were followed for a mean of 38 months (range 28–52). The mean left ventricular (LV) ejection fraction (EF) was 30 ± 9%, and peak VO 2 17.2 ± 6.5 ml/kg/min. LVEF correlated weakly with peak VO 2 (r = 0.21), while systolic and early diastolic LV longitudinal function correlated best [early diastolic peak velocity at the mitral annulus (e’): r = 0.38; global longitudinal strain (GLS): r = −0.4; p < 0.001 for both]. By multiple variable regression analysis, the best prediction of peak VO 2 was derived from a model based on age, mitral annulus end-diastolic peak velocity (a’), GLS, right ventricular (RV) systolic strain and left atrial systolic strain (r 2 = 0.57; p < 0.0001). The 2 best independent predictors of adverse cardiovascular events at 28 months were GLS (odds ratio 1.31, p < 0.001; prognostic cut-off = −8%) and RV systolic strain (odds ratio 1.05, p = 0.01; prognostic cut-off −22%). Resting RV and LV longitudinal functions explained the presence of exercise intolerance and were more reliable predictors of adverse cardiovascular events than CPET measurements.