冠状动脉慢性完全闭塞病变侧支压力大小与闭塞远端心肌灌注的临床研究

目的 分析冠状动脉慢性完全闭塞病变（CTO）侧支大小与闭塞远端心肌灌注水平的关系和闭塞远端不同灌注水平对CTO开通术后远端心肌灌注恢复和心功能的影响。 方法 连续入选2018年1月1日至2018年10月1日就诊于西京医院的CTO患者。所有患者术前完善心肌声学造影以评价闭塞远端心肌血流灌注[峰值强度(A)、血流速度(β)、心肌血流量(A×β）]。开通CTO支架植入后使用温度压力导丝测定冠状动脉楔压Pw，并计算侧支压力指数（CPI）。以CPI≥0.25和CPI<0.25分为侧支丰富组和侧支不良组。观察两组患者术前在A、β、A×β方面的差异。采用心肌声学造影半定量分析，根据闭塞远端心肌灌注水平分为灌注缺损组和灌注延迟组。观察两组患者术前、术后1d、术后1个月在A、β、A×β方面的差异以及心功能恢复情况。 结果 ①CPI<0.25和CPI≥0.25两组患者闭塞远端心肌灌注水平在术前，术后1d，术后1个月的差异无统计学意义。②灌注缺损组术前A[（4.9±0.6）dB vs (5.8±0.8) dB]和A×β[（14.1±2.4）dB/s vs (16.2±2.2) dB/s]显著低于灌注延迟组（均P<0.01）；β在两组间的差异无统计学意义。③CTO开通术后1d，1个月，灌注缺损组A[术后1d (6.1±0.8)dB vs (6.9±0.9) dB，P=0.01]，[术后1个月（7.7±1.1）dB vs（8.5±1.0）dB，P<0.05]仍显著低于灌注延迟组；灌注延迟组和灌注缺损组远端心肌的 β和A×β差异无统计意义。④灌注缺损组术前左室射血分数(LVEF)显著低于灌注延迟组[（45±7）%vs（49±4）%，P<0.05）]；CTO开通术后1个月灌注延迟组射血分数较术前提高，差异有统计学意义[（50±3）% vs（49±4）%，P=0.02]。灌注缺损组CTO开通术后1个月的LVEF与术前相比未见明显变化[（45±7）% vs (45±6)%]。 结论 ①CPI无法预测CTO闭塞远端心肌的灌注水平；②CTO开通后，闭塞远端心肌的灌注恢复不受CPI的影响；③CTO开通后远端心肌灌注水平和心功能的恢复受术前闭塞远端心肌灌注水平的影响。

Clinical study of relationship between collateral pressure index and distal myocardial perfusion in coronary chronic total occlusion

AIM To analyze the relationship between collateral pressure index of coronary chronic total occlusion (CTO) and distal myocardial perfusion of occlusion and to investigate the effect of different perfusion levels of occluded distal end on myocardial perfusion recovery and cardiac functions after CTO revascularization. METHODS Patients who had been diagnosed with coronary chronic total occlusion by coronary angiography were enrolled from 2018-1-1 to 2018-10-30 in Xijing Hospital. Myocardial contrast echocardiography (MCE) was performed before revascularization to evaluate myocardial perfusion by some parameters, including peak intensity A, blood flow velocity β and myocardial blood flow A×β. After CTO revascularization, coronary wedge pressure (Pw) was measured by a temperature-pressure guide wire and collateral pressure index (CPI) was calculated from Pw. Patients were divided into two groups according to CPI≥2.5 or CPI<2.5 and the difference of A, β and A×β were compared between the two groups. In addition, according to semi-quantitative analysis of MCE, perfusion-defects group and perfusion-delay group were divided by myocardial perfusion levels of distal occlusion and the difference of recovery of perfusion and cardiac function after CTO revascularization was analyzed between the two groups. RESULTS There was no difference in myocardial perfusion levels of distal occlusion between CPI<0.25 group and CPI>0.25 group. A[(4.88±0.64)dB, (5.78±0.82)dB, P<0.01] and β [(14.08±2.41)s, (16.17±2.24)s, P<0.01] in perfusion-defects group were significantly lower than those in perfusion-delay group. No significant difference was found in β and A×β between perfusion-defects group and perfusion-delay group at 1 day and 1 month post CTO-PCI. A in perfusion-defects group was lower than that in perfusion-delay group at both 1 day [(6.14±0.82)dB, (6.91±0.93)dB, P = 0.01] and 1 month post CTO-PCI [(7.71±1.07)dB, (8.52±1.02)dB, P<0.05]. Before CTO-PCI, the ejection fraction in perfusion-defects group was lower than that in perfusion-delay group [(0.45±0.07), (0.49±0.04), P<0.05]. One month after CTO-PCI, the ejection fraction in perfusion-delay group was higher than that before PCI [(0.50±0.03), (0.49±0.04), P<0.05]. However, compared with the ejection fraction before PCI, no significant difference was found in perfusion-defects group 1 month post CTO-PCI [(0.45±0.07), (0.45±0.06), P = 0.54]. CONCLUSION Collateral pressure index cannot predict distal myocardial perfusion of CTO before CTO revascularization. After CTO revascularization, the recovery of myocardial perfusion is not affected by collateral pressure index. The recovery of cardiac functions and distal myocardial perfusion of CTO are subject to the level of original myocardial perfusion of the CTO territory.