冠状动脉血流显像评价主动脉瓣狭窄瓣膜置换术后的冠状动脉血流储备

Evaluation of coronary flow reserve after aortic valve replacement for aortic stenosis using coronary flow imaging

目的 应用冠状动脉血流显像技术结合双嘧达莫负荷试验探讨主动脉瓣狭窄患者主动脉瓣置换术 (AVR)前后的冠脉血流储备 (CFR)的变化。方法 分别在AVR前和AVR后 6个月两种情况下检测 3 1例单纯主动脉瓣狭窄患者的冠状动脉左前降支 (LAD)远端的舒张期血流速度峰值 (CPV)和速度时间积分 (VTI) ;然后经静脉注射双嘧达莫 ,测量达到最大充血状态的CPV和VTI ;CFR由用药后与用药前冠脉血流的CPV比和VTI比来计算 ;测量受试者的室间隔厚度 (IVST )、左室后壁厚度 (PWT)、左室内径 (LVID)、冠状动脉左前降支远端直径 (LADD) ;计算CPV和VTI与IVST的比值。结果 2 4例患者得到了手术前后成对的完整资料 ,IVST和PWT在主动脉瓣置换术后较术前明显减小 ,LVID却无明显变化 ;LADD也从术前的 (2 .2 72± 0 .0 15 )mm下降到 (2 .2 3 1± 0 .0 47)mm (P >0 .0 5 )。在静息状态 ,CPV和VTI在手术后稍降低 ,差别无显著性意义 (P >0 .0 5 ) ;CPV和VTI与IVST的比值均轻度增加 (P >0 .0 5 ) ;在充血状态 ,CPV和VTI在手术前后均明显增加 ,但术后的增加程度高于术前 ;术后的CPV和VTI与IVST的比值均显著增加 (P <0 .0 0 1) ;术后的冠脉血流储备也显著增加。结论 主动脉瓣狭窄患者在主动脉瓣置换术后冠脉血流储备明显增加 。

Objective To investigate the coronary flow and coronary flow reserve (CFR) before and after aortic valve replacement (AVR) using coronary flow imaging combined with dipyridamole stress test.Methods Tirty one patients with pure aortic stenosis,left ventricular (LV) hypertrophy and normal coronary arteriograms were investigated.Patients underwent coronary flow imaging combined with dipyridamole stress test on two occasions immediately before AVR and six months postoperatively.Interventricular septal thickness (IVST),posterior wall thickness (PWT) and left ventricular internal diameter (LVID),distal left anterior descending coronary arteries diameter (LADD),flow and CFR were assessed on each occasion.CFR was defined as the ratio of coronary peak velocity (CPV) or velocity time integral (VTI) during maximum pharmacological vasodilation to CPV or VTI at rest.Results Paired data were subsequently available in 24 patients.Pre to post AVR a significant decrease was seen in IVST and PWT.LADD fell from ( 2.272 ± 0.015 ) to ( 2.231 ± 0.047 )mm.Pre to post AVR there was no significant change in resting parameters of LADD,LVID,CPV,VTI, CPV/IVST and VTI/IVST ,but there was significant increase in hyperemic CPV,VTI, CPV/IVST and VTI/IVST .CFR,therefore,increased significantly.Conclusions CFR was great increase after AVR for aortic stenosis.This increase occurs in trandem with regression of LV hypertrophy.