title: The effects of acute coronary occlusion on noninvasive echocardiographically derived systolic and diastolic myocardial strain rates.
abstract: To compare the magnitude and rates of change of peak systolic (epsilon(')(SYS)) and diastolic (epsilon(')(DIAS)) strain rates, as measured using tissue Doppler echocardiography, to pressure and volumes left-ventricular indices during acute coronary occlusion.Six closed-chest dogs had a combination high-fidelity conductance pressure transducer placed into the left ventricle for determination of end-diastolic and end-systolic pressures (EDP and ESP) and volumes (EDV, ESV, and ejection fraction [EF]). Other indices included the time constant of left-ventricular relaxation (tau), +dP/dt(max), -dP/dt(max), end-systolic pressure/volume index (ESPV). A coronary angioplasty catheter was positioned into the left-anterior descending coronary artery. During coronary occlusion, strain rates and hemodynamic parameters were recorded continuously for 2 minutes.During occlusion, significant decreases in strain rates occurred within 30 seconds. Systolic indices (ESPV and +dP/dt(max)) changed at rates similar to epsilon(')(SYS) (each p = NS). Diastolic indices (tau, EDP, EDV, -dp/dt(max)) also changed at rates similar to epsilon(')(DIAS) (each p = NS). However, EF decreased at a significantly slower rate than did strain rates (p < 0.05).CONCLUSIONS:Peak systolic and diastolic strain rates decrease with acute ischemia similar to corresponding indices of left-ventricular systolic and diastolic function. Strain rates may be used in the noninvasive assessment of ischemic-induced left-ventricular dysfunction.
authors.affiliation: The Cardiovascular Imaging Center, The Cleveland Clinic Foundation, Cleveland, Ohio, USA
authors.initials: MS
authors.lastname: Firstenberg
authors.initials: NL
authors.lastname: Greenberg
authors.initials: NG
authors.lastname: Smedira
authors.initials: P
authors.lastname: Castro
authors.initials: JD
authors.lastname: Thomas
authors.initials: MJ
authors.lastname: Garcia