Asynchronous (segmental early) relaxation impairs left ventricular filling in patients with coronary artery disease and normal systolic function

Abstract

Asynchronous segmental early relaxation, defined as a localized early segmental outward motion of the left ventricular endocardium during isovolumetric relaxation, has been associated with an altered left ventricular relaxation rate. To determine whether asynchronous segmental early relaxation also results in impaired left ventricular filling, early diastolic ventricular wall motion and Doppler-derived left ventricular filling indexes were examined in 25 patients with documented coronary artery disease and normal systolic function. Patients were further classified into two groups according to the presence (n = 15, group 1) or absence (n = 10, group 2) of asynchronous early relaxation at left ventriculography. A third group of 10 age-matched normal subjects served as a control group.No differences were observed between the two patient groups with coronary artery disease with respect to age, gender distribution, heart rate, left ventricular systolic and diastolic presssures or extent and severity of coronary artery disease. No differences in transmitral filling dynamics were observed between group 2 patients and age-matched control subjects. Conversely, group 1 patients had significantly lower peak early filling velocities (44 ± 11 vs. 58 ± 11 cm/s, p < 0.01), larger atrial filling fraction (45 ±4% vs. 38 ± 4%, p < 0.001), lower ratio of early to late transmitral filling velocities (0.6 ± 0.08 vs. 0.99 ± 0.18, p < 0.001) and a longer isovolumetric relaxation period (114 ± 12 vs. 90 ± 6 ms, p < 0.001) compared with group 2 patients and control subjects. In patients, significant correlations were observed between the severity of asynchrony and peak early filling velocity (r = −0.76), atrial filling fraction (r = 0.74) and the ratio of early to late transmitral filling velocities (r = −0.89).Thus, in patients with coronary artery disease and normal systolic function, asynchronous segmental early relaxation is associated with disturbed left ventricular filling dynamics, the severity of which increases with the severity of regional diastolic asynchrony.