摘要
目的 :探讨急性缺血心肌的应变和应变率参数变化特征 ,并筛选最佳参数。方法 :12只健康杂种犬 ,分别于冠状动脉 (冠脉 )闭塞前、结扎后 15min(I15)采集图像。分别比较缺血节段 (IS)和非缺血节段 (NS)在冠脉结扎前后的参数变化 ,并对IS和NS在I15时的参数进行比较。结果 :IS的I15时与基础状态相比收缩期峰值应变率 (SSR)、舒张早期应变率 (ESR)、收缩期应变 (εS)均明显降低 (均P <0 .0 5 ) ,IS等容舒张期应变率 (IVRSR)、等容舒张期应变率与收缩期应变率之比 (IVRSR/SSR)、收缩后应变 (εPSS)在I15时明显增大 ,其中IVRSR/SSR变化最显著。NS在冠脉结扎前后各参数无明显差异。结论 :应变和应变率显像能显示急性心肌缺血各心肌节段的变化特征 ,IVRSR/SSR是反映心肌缺血的重要参数。
Objective:To investigate changes of strain and strain rate parameters in acute ischemic myocardium and define an optimal index for differentiating ischemic from normal myocardium.Method:Twelve healthy open-chest mongrel dogs underwent echocardiography before and during coronary artery occlusion. Longitudinal strain rates were displayed during systole(S SR ), isovolumic relaxation(IVR SR ) and fast filling(E SR ) phases in both ischemic and normal myocardium. Systolic strain(ε S ) and postsystolic strain(ε PSS)were also displayed. All of these parameters obtained from different myocardial segments were compared between at baseline and during ischemia.Result: During ischemia, S SR , E SR and ε S in ischemic segments were significantly reduced than those at baseline, whereas IVR SR in all ischemic segments became negative and larger in magnitude than S SR during ischemia. IVR SR /S SR and ε PSS were also significantly increased. Change in IVR SR /S SR was most remarkable. Conclusion:Strain and strain rate imaging can display the changes occurred during acute myocardial ischemia. IVR SR /S SR have the ability to depict the characteristics of PSS to some extent and therefore is an valuable parameter in differentiating ischemic from normal segments.
出处
《临床心血管病杂志》
CAS
CSCD
北大核心
2004年第6期364-366,共3页
Journal of Clinical Cardiology
关键词
心肌缺血
急性
超声检查
应变率
收缩后缩短
Acute myocardial ischemia
Ultrasonography
Strain rate
Postsystolic shorting
