Lombardo A, Loperfido F, Trani C, Pennestrí F, Rossi E, Giordano A, Possati G, Maseri A
Institute of Cardiology, Catholic University Sacro Cuore, Rome, Italy.
J Am Coll Cardiol. 1997 Sep;30(3):633-40. doi: 10.1016/s0735-1097(97)00202-7.
We sought to investigate the effects of revascularization on the contractile reserve of dysfunctional myocardium.
The improvement in dysfunctional but viable myocardium after revascularization is frequently less than expected from the amount of contractile reserve detected on dobutamine stress echocardiography. The fate of the contractile reserve, when it does not result in an adequate contractile recovery, is unknown.
Basal contraction and contractile reserve of infarct zones were assessed by dobutamine stress echocardiography in 21 postinfarction male patients before and > 3 months after revascularization (30 infarct zones; mean +/- SD left ventricular ejection fraction 35 +/- 8%). An infarct zone wall motion score index (WMSI) was calculated.
Before revascularization, contractile reserve was present in 14 infarct zones (12 patients) and absent in 16 (9 patients). After revascularization, ejection fraction increased by 5 +/- 4% (p < 0.01) in patients classified as positive for contractile reserve and remained unchanged in those classified as negative. New York Heart Association classification improved in 58.3% and 22.2% of patients, respectively. Basal contraction improved in eight zones with previous contractile reserve (57.1%) and in one zone without (6.3%) (p < 0.01). Contractile reserve was still evident in 13 zones with previous contractile reserve (93%; 8 with contractile recovery), and it developed in 6 zones without (38%; none with contractile recovery). WMSI values after revascularization were decreased from values before revascularization during low dose dobutamine in zones with and without previous contractile reserve (p < 0.01 and < 0.05, respectively).
After revascularization, contractile reserve is maintained or even increases in viable infarct zones that do not recover as expected. It may also develop in some infarct zones judged not to be viable before revascularization. This increased contractile reserve may play a role in the functional improvement of patients after revascularization.
我们试图研究血运重建对功能失调心肌收缩储备的影响。
血运重建后功能失调但存活的心肌改善情况常常低于多巴酚丁胺负荷超声心动图检测到的收缩储备量所预期的程度。当收缩储备未导致充分的收缩恢复时，其转归尚不清楚。
通过多巴酚丁胺负荷超声心动图评估21例心肌梗死后男性患者血运重建前及血运重建3个月后梗死区域的基础收缩和收缩储备（30个梗死区域；平均±标准差左心室射血分数35±8%）。计算梗死区域壁运动评分指数（WMSI）。
血运重建前，14个梗死区域（12例患者）存在收缩储备，16个（9例患者）不存在收缩储备。血运重建后，收缩储备分类为阳性的患者射血分数增加5±4%（p<0.01），分类为阴性的患者射血分数保持不变。纽约心脏协会心功能分级分别在58.3%和22.2%的患者中得到改善。8个先前有收缩储备的区域（57.1%）基础收缩得到改善，1个无收缩储备的区域（6.3%）基础收缩得到改善（p<0.01）。13个先前有收缩储备的区域（93%；8个有收缩恢复）收缩储备仍然明显，6个无收缩储备的区域（38%；无收缩恢复）出现收缩储备。在有和无先前收缩储备的区域，血运重建后低剂量多巴酚丁胺期间WMSI值均低于血运重建前（分别为p<0.01和<0.05）。
血运重建后，未按预期恢复的存活梗死区域收缩储备得以维持甚至增加。在血运重建前判定为无存活心肌的一些梗死区域也可能出现收缩储备。这种增加的收缩储备可能在血运重建后患者的功能改善中起作用。
