Coronary chronic total occlusion (CTO) is characterized by the presence of collateral blood vessels which can provide additional blood supply to CTO-artery dependent myocardium. Successful CTO recanalization is followed by significant decrease in collateral donor artery blood flow and collateral derecruitment, but data on coronary hemodynamic changes in relation to myocardial function are limited. We assessed changes in coronary flow velocity reserve (CFVR) by echocardiography in collateral donor and recanalized artery following successful opening of coronary CTO. Our study enrolled 31 patients (60 ± 9 years; 22 male) with CTO and viable myocardium by SPECT scheduled for percutaneous coronary intervention (PCI). Non-invasive CFVR was measured in collateral donor artery before PCI, 24 h and 6 months post-PCI, and 24 h and 6 months in recanalized artery following successful PCI of CTO. Collateral donor artery showed significant increase in CFVR 24 h after CTO recanalization compared to pre-PCI values (2.30 ± 0.49 vs. 2.71 ± 0.45, p = 0.005), which remained unchanged after 6-months (2.68 ± 0.24). Baseline blood flow velocity of the collateral donor artery significantly decreased 24 h post-PCI compared to pre-PCI (0.28 ± 0.06 vs. 0.24 ± 0.04 m/s), and remained similar after 6 months, with no significant difference in maximum hyperemic blood flow velocity pre-PCI, 24 h and 6 months post-PCI. CFVR of the recanalized coronary artery 24 h post-PCI was 2.55 ± 0.35, and remained similar 6 months later (2.62 ± 0.26, p = NS). In patients with viable myocardium, prompt and significant CFVR increase in both recanalized and collateral donor artery, was observed within 24 h after successful recanalization of CTO artery, which maintained constant during the 6 months. ClinicalTrials.gov (Number NCT04060615 ).

中文翻译：

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成功地对存活心肌患者进行冠状动脉慢性完全阻塞后，迅速并持续改善冠状动脉血流储备。

冠状动脉慢性完全闭塞（CTO）的特征是侧支血管的存在，可为依赖CTO动脉的心肌提供额外的血液供应。成功的CTO再通后，侧支供体动脉血流量和侧支减少量显着减少，但有关冠脉血流动力学变化与心肌功能相关的数据有限。我们成功地打开了冠状动脉CTO后，通过超声心动图评估了侧支供体和再通小动脉中冠状动脉血流储备量（CFVR）的变化。我们的研究通过SPECT纳入了31例CTO和存活心肌的患者（60±9岁； 22例男性），计划进行经皮冠状动脉介入治疗（PCI）。在PCI前，PCI后24小时和6个月，在侧支供体动脉中测量无创CFVR，成功进行CTO PCI后，在再通动脉中分别放置24小时和6个月。与PCI之前的值相比，CTO再通气后24 h，侧支供体动脉的CFVR显着增加（2.30±0.49 vs. 2.71±0.45，p = 0.005），六个月后仍保持不变（2.68±0.24）。与PCI前相比，PCI后24 h侧支供体动脉的基线血流速度显着降低（0.28±0.06 vs. 0.24±0.04 m / s），并且在6个月后保持相似，最大充血量无明显差异PCI前，PCI后24小时和6个月的流速。PCI后24小时，再通冠状动脉的CFVR为2.55±0.35，并在6个月后保持相似（2.62±0.26，p = NS）。在存活心肌的患者中，再通和旁侧供体动脉的CFVR均显着增加，在成功再通CTO动脉后24小时内观察到这种现象，在6个月内保持不变。ClinicalTrials.gov（编号NCT04060615）。