Kensuke Matsumoto1, Hidekazu Tanaka2, Junichi Ooka2, Yoshiki Motoji2, Takuma Sawa2, Yasuhide Mochizuki2, Keiko Ryo2, Kazuhiro Tatsumi2, Ken-Ichi Hirata2. 1. Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan kenmatsu@med.kobe-u.ac.jp. 2. Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.
Abstract
AIMS: The purpose of this study was to investigate the prognostic impact of the changes in ventriculo-arterial (VA) coupling during dobutamine stress on the cardiovascular events for patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: For this study, 89 DCM patients with ejection fractions of 32 ± 10% and 30 normal controls were recruited. Ees was estimated with the non-invasive single-beat method using three-dimensional echocardiography at rest and during dobutamine stress (20 μg/kg/min). Effective arterial elastance (Ea) was calculated as left ventricular (LV) end-systolic pressure divided by stroke volume, and VA coupling was calculated as Ea/Ees. Event-free survival was then tracked for 32 months. At baseline, VA coupling was far from optimal in patients with DCM compared with controls (Ea/Ees: 2.49 ± 1.02 vs. 1.04 ± 0.21, P < 0.001). During the follow-up period, 22 patients developed adverse cardiovascular events. During dobutamine stress, VA coupling was significantly improved in patients without cardiovascular events (from 2.47 ± 1.09 to 1.59 ± 0.68, P < 0.001), but remained unchanged in those with cardiovascular events. A multivariate Cox proportional-hazards analysis revealed that age, NYHA functional class (>II), and the change in VA coupling during dobutamine stress were the independent determinants of cardiovascular events (P < 0.05, <0.01, and <0.001, respectively). When patients were divided into two subgroups based on the finding of receiver operating characteristic curve analysis, patients with good VA coupling reserve (cut-off: change in VA coupling> 0.29) showed significantly favourable event-free survival than those with poor VA coupling reserve (P < 0.001). CONCLUSIONS: Improvement in VA coupling during dobutamine stress is an important determinant of cardiovascular outcome for patients with DCM. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: The purpose of this study was to investigate the prognostic impact of the changes in ventriculo-arterial (VA) coupling during dobutamine stress on the cardiovascular events for patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: For this study, 89 DCMpatients with ejection fractions of 32 ± 10% and 30 normal controls were recruited. Ees was estimated with the non-invasive single-beat method using three-dimensional echocardiography at rest and during dobutamine stress (20 μg/kg/min). Effective arterial elastance (Ea) was calculated as left ventricular (LV) end-systolic pressure divided by stroke volume, and VA coupling was calculated as Ea/Ees. Event-free survival was then tracked for 32 months. At baseline, VA coupling was far from optimal in patients with DCM compared with controls (Ea/Ees: 2.49 ± 1.02 vs. 1.04 ± 0.21, P < 0.001). During the follow-up period, 22 patients developed adverse cardiovascular events. During dobutamine stress, VA coupling was significantly improved in patients without cardiovascular events (from 2.47 ± 1.09 to 1.59 ± 0.68, P < 0.001), but remained unchanged in those with cardiovascular events. A multivariate Cox proportional-hazards analysis revealed that age, NYHA functional class (>II), and the change in VA coupling during dobutamine stress were the independent determinants of cardiovascular events (P < 0.05, <0.01, and <0.001, respectively). When patients were divided into two subgroups based on the finding of receiver operating characteristic curve analysis, patients with good VA coupling reserve (cut-off: change in VA coupling> 0.29) showed significantly favourable event-free survival than those with poor VA coupling reserve (P < 0.001). CONCLUSIONS: Improvement in VA coupling during dobutamine stress is an important determinant of cardiovascular outcome for patients with DCM. Published on behalf of the European Society of Cardiology. All rights reserved.