Noninvasive quantification of the contractile reserve of stunned myocardium by ultrasonic strain rate and strain | |
Article | |
关键词: DOBUTAMINE ECHOCARDIOGRAPHY; DOPPLER-ECHOCARDIOGRAPHY; INOTROPIC STIMULATION; CORONARY ANGIOPLASTY; THROMBOLYTIC THERAPY; ISCHEMIC MYOCARDIUM; VELOCITY-GRADIENT; CONSCIOUS DOGS; DYSFUNCTION; INFARCTION; | |
DOI : 10.1161/hc3501.093818 | |
来源: SCIE |
【 摘 要 】
Background-We sought to investigate ultrasonic strain rate and strain as new indices to quantify the contractile reserve of stunned myocardium during dobutamine infusion. Methods and Results-Stunning of the left ventricular posterior wall was induced in 9 closed-chest pigs after 30 minutes of severe hypoperfusion followed by 60 minutes of reperfusion of the left circumflex coronary artery territory. A second group of 7 animals had no coronary occlusion and served as normal controls. An incremental dobutamine infusion protocol was used in both groups. Changes in regional radial function were monitored by use of ultrasound-derived maximal systolic radial strain rate (SR) and systolic strain (epsilon). In the control group, dobutamine induced an increase in both SR and maximal dP/dt, which correlated linearly (r = 0.85). Conversely, epsilon values increased at low doses of dobutamine (2.5 to 5 mug.kg(-1).min(-1)) but decreased during higher infusion rates (10 to 20 mug.kg(-1).min(-1)). During circumflex hypoperfusion, SR and epsilon of the posterior wall decreased from 5.0 +/- 0.3 s(-1) and 63 +/- 6% to 2.9 +/- 0.3 s(-1) and 27 +/- 4%, respectively (P < 0.01). After 60 minutes of reperfusion, SR and
【 授权许可】
Free