Restraint to the left ventricle alone is superior to standard restraint.
Restraint to the left ventricle alone is superior to standard restraint.
复制标题
单独限制左心室优于标准限制。
DOI：
10.1016/j.jtcvs.2012.09.027
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Chen,FrederickY
中科院分区：
文献类型：
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作者：
Mokashi,SuyogA;Lee,LawrenceS;Schmitto,JanD;Ghanta,RaviK;McGurk,Siobhan;Laurence,RitaG;Bolman3rd,RMorton;Cohn,LawrenceH;Chen,FrederickY
目的 在标准心室约束治疗中，对整个心室表面施加单级约束。我们之前表明，在高约束水平下，由于右心室壁薄，即使左心室不受影响，也会发生心包填塞。我们现在假设仅对左心室施加约束可以实现更高水平的约束，从而增加对左心室的益处。方法在健康和心肌病绵羊心脏中分析仅对左心室施加约束的急性效应。通过仅放置在左心室周围的充满液体的心外膜气球进行约束治疗。约束水平由舒张末期测量的球囊管腔压力定义。在逐渐升高的约束水平（0、3、5、8、10、12 和 14 毫米汞柱）下，测量了健康绵羊 (n = 5) 和心力衰竭绵羊 (n = 6) 的跨壁心肌左心室压力 (Ptm= 左心室压力 - 球囊压力) 和心肌耗氧量指数。 结果从 0 毫米汞柱增加到 14 毫米汞柱的约束会降低跨壁心肌压力减少 48.8% (P ≤ .02)，左心室张力时间指数减少 39.1% (P ≤ .01)，压力-容积面积减少 58.4% (P ≤ .01)。同样，每搏功减少了 57.9% (P ≤ .03)。全身血流动力学没有变化。健康动物和心力衰竭动物之间所有指数的趋势没有差异。结论我们之前表明，在标准约束下，右心室填塞在高约束水平下发生，限制了约束治疗。我们现在表明，仅对左心室施加约束可以增加约束水平，而不会引起右心室或左心室填塞，从而获得更大的治疗效果。我们的结论是，部分左心室约束可能比标准约束更有效。
OBJECTIVEIn standard ventricular restraint therapy, a single level of restraint is applied to the entire ventricular surface. We showed previously that at high restraint levels, cardiac tamponade develops because of the thin-walled right ventricle, even while the left ventricle remains unaffected. We now hypothesize that applying restraint exclusively to the left ventricle permits higher levels of restraint, resulting in increased benefit to the left ventricle.METHODSThe acute effect of restraint applied to the left ventricle alone was analyzed in healthy and cardiomyopathic sheep hearts. Restraint therapy was applied by fluid-filled epicardial balloons placed solely around the left ventricle. Restraint level was defined by the measured balloon luminal pressure at end diastole. At incrementally higher restraint levels (0, 3, 5, 8, 10, 12, and 14 mm Hg), transmural myocardial left ventricular pressure (Ptm= Left ventricle pressure − Balloon pressure) and indices of myocardial oxygen consumption were measured in healthy sheep (n = 5) and in sheep with heart failure (n = 6).RESULTSIncreasing restraint from 0 to 14 mm Hg decreased transmural myocardial pressure by 48.8% (P ≤ .02) and the left ventricle tension-time index by 39.1% (P ≤ .01), and the pressure–volume area decreased by 58.4% (P ≤ .01). Similarly, stroke work decreased by 57.9% (P ≤ .03). Systemic hemodynamics were unchanged. There was no difference in the trend for all indices between animals that were healthy and those with heart failure.CONCLUSIONSWe showed previously that, with standard restraint, right ventricle tamponade develops at high restraint levels, limiting restraint therapy. We now show that restraint applied to the left ventricle alone permits increased restraint levels, without causing right ventricle or left ventricle tamponade, for greater therapeutic benefit. We conclude that partial left ventricle restraint may be more effective than standard restraint.