Frierson J H, Penn M S, Lafont A M, Kultursay H, Marwick T H, Kottke-Marchant K, Dimas A P, Meaney K M, Fouad-Tarazi F M, Whitlow P L
Department of Cardiology, Cleveland Clinic Foundation, Ohio 44195-5066.
J Am Coll Cardiol. 1992 Dec;20(7):1642-9. doi: 10.1016/0735-1097(92)90461-u.
To simulate a human catheterization laboratory setting of controlled reperfusion during myocardial infarction, regional infusion of commercially available Buckberg cardioplegic solution and peripheral vented bypass were administered in the closed chest dog.
Studies in open-chest dogs have demonstrated a significant reduction in infarct size and improvement in regional wall motion with a similar controlled reperfusion method using infusion of substrate-enriched (Buckberg) cardioplegic solution during cardiopulmonary bypass coupled with left ventricular venting.
After 100 or 180 min of balloon occlusion of the proximal left anterior descending artery, controlled reperfusion was performed with cardioplegic infusion and vented bypass. Dogs matched for occlusion time underwent balloon deflation without bypass or cardioplegia (uncontrolled reperfusion groups). Microspheres were used to quantify coronary ischemia during balloon inflation. All four groups (n = 8 to 9 per group) were followed up at 1 week to determine regional wall motion and infarct size.
Qualitative echocardiographic analysis demonstrated no significant difference among groups in recovery of regional wall motion at 1 week; however, wall motion improved significantly in all groups between the ischemia and 1-week recovery periods. The histologic infarct size compared with the area at risk for dogs with uncontrolled versus controlled reperfusion, respectively, was 17.9 +/- 10.5% versus 31.9 +/- 8.3% (p < 0.05) for dogs with 100 min of occlusion and 40.1 +/- 11.7% versus 46.2 +/- 8.4% (p = NS) for dogs with 180 min of occlusion. A greater rate-pressure product in the dogs with controlled reperfusion after 100 min of occlusion (p < 0.05) may explain the larger infarct size observed for that group.
These results demonstrate that regional infusion of substrate-enriched cardioplegic solution in combination with peripheral vented bypass does not further reduce infarct size after prolonged ischemia in the closed chest dog (compared with uncontrolled reperfusion).
为模拟心肌梗死期间可控再灌注的人体导管插入实验室环境，对闭胸犬进行市售巴克伯格心脏停搏液的区域灌注和外周排气旁路手术。
在开胸犬身上进行的研究表明，在体外循环期间使用富含底物的（巴克伯格）心脏停搏液灌注并结合左心室排气，采用类似的可控再灌注方法，可使梗死面积显著减小，局部室壁运动得到改善。
在左前降支近端球囊闭塞100或180分钟后，进行心脏停搏液灌注和排气旁路的可控再灌注。闭塞时间匹配的犬只进行球囊放气，不进行旁路手术或心脏停搏（不可控再灌注组）。在球囊充盈期间，使用微球来量化冠状动脉缺血情况。所有四组（每组n = 8至9只）在1周时进行随访，以确定局部室壁运动和梗死面积。
定性超声心动图分析显示，1周时各组局部室壁运动恢复情况无显著差异；然而，在缺血期和1周恢复期之间，所有组的室壁运动均有显著改善。对于闭塞100分钟的犬只，不可控再灌注与可控再灌注的犬只相比，组织学梗死面积与危险区域面积之比分别为17.9±10.5% 对31.9±8.3%（p < 0.05）；对于闭塞180分钟的犬只，该比例分别为40.1±11.7% 对46.2±8.4%（p = 无显著性差异）。闭塞100分钟后，可控再灌注犬只的心率与收缩压乘积更高（p < 0.05），这可能解释了该组观察到的较大梗死面积。
这些结果表明，在闭胸犬长时间缺血后，与不可控再灌注相比，富含底物的心脏停搏液区域灌注联合外周排气旁路并不能进一步减小梗死面积。
