Isovolumic Relaxation Flow Propagation Velocity in Patients with Diseases Impairing Ventricular Relaxation Wen-Chol Voon, MD, Ho-Ming Su, MD, Hsueh-Wei Yen, MD, Tsung-Hsien Lin, MD, Chih-Sheng Chu, MD, Kun-Tai Lee, MD, Wen-Ter Lai, MD, and Sheng-Hsiung Sheu, MD, Kaohsiung, Taiwan To evaluate the propagation velocity of isovolumic relaxation flow within the left ventricle (IRFPV) associated with impaired ventricular relaxation, 49 patients with diseases known to impair ventricular relaxation (disease group) and 38 age-matched con- trol subjects (control group) were studied. IRFPV was measured as the slope of the first aliasing velocity line segment of the isovolumic relaxation flow wave front in the color M-mode Doppler echo- cardiogram. Compared with the control group, the disease group had thicker interventricular septum and left ventricular posterior wall, more left ventric- ular mass, and lower early diastolic mitral annular velocity (8  3 vs 11  4 cm/s, P < .001), early (E) wave propagation velocity (47  16 vs 70  41 cm/s, P  .002), and IRFPV (193  149 vs 395  220 cm/s, P < .001). No matter in subgroup or whole popula- tion analysis, either the early diastolic mitral annu- lar velocity or the E wave propagation velocity was selected as one of the determinants of IRFPV. In conclusion, diseases impairing ventricular relax- ation may retard IRFPV. (J Am Soc Echocardiogr 2005; 18:221-5.) Ventricular diastolic dysfunction, an early sign of cardiac disease, often precedes systolic dysfunction. For evaluating ventricular diastolic function (ie, re- laxation and stiffness) Doppler echocardiography is the most frequently used tool. Transmitral flow pattern of reversed early (E)-to- late (A) ratio with prolonged deceleration time of the E wave was once deemed the classic symbol of impaired relaxation. However, it is preload-depen- dent and neither the transmitral E-to-A ratio nor the deceleration time of the E wave bears a significant correlation with the isovolumic relaxation time con- stant. 1,2 In contrast, the E wave propagation velocity (EPV) has been shown to be negatively correlated with the isovolumic relaxation time constant. 3-5 However, its preload independence remains contro- versial. 5-7 There are still no data concerning the impact of impaired relaxation on the propagation velocity of isovolumic relaxation flow within the left ventricle (IRFPV). It is hypothesized that relaxation impair- ment may slow down IRFPV and the aim of this study was to test the hypothesis. METHODS Study Participants The study population comprised control and disease groups. The control group included 38 participants free of acute or chronic illness by history and physical examina- tion, physically active without limitation of daily life, in sinus rhythm, without significant cardiac abnormalities on echocardiograms, and taking no drugs affecting cardiovas- cular function. The disease group included 49 patients with diseases known to impair ventricular relaxation (40 with systemic hypertension, 14 with diabetes, 2 with valvular aortic stenosis, and 4 with old myocardial infarc- tion or angiogram-confirmed coronary artery disease). The drugs for disease control, including -blockers (25%), calcium blockers (41%), angiotensin-converting enzyme inhibitors (25%), angiotensin II antagonists (25%), nitrates (18%), and diuretics (18%), were continued without inter- ruption. No age difference was noted between the control and disease groups (56  11 vs 60  10 years, P = .121). At echocardiographic examinations, mild mitral annular calcifi- cation was detected in 3 control subjects and 4 patients, and mild mitral regurgitation in 19 control subjects and 26 patients. Only one patient had moderate mitral regurgitation, with the ratio of the regurgitation jet area to the left atrial area between 20% and 40%. This study was approved by our institutional review committee. Doppler Echocardiographic Evaluation After agreement to the clearly described study procedures was acquired, the echocardiographic examination was From the Division of Cardiology, Department of Internal Medi- cine, Kaohsiung Medical University. Reprint requests: Wen-Chol Voon, MD, Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University, 100 Shih-Chuan First Rd, Kaohsiung 807, Taiwan (E-mail: wcvoon@giga.net.tw). 0894-7317/$30.00 Copyright 2005 by the American Society of Echocardiography. doi:10.1016/j.echo.2004.12.008 221