Prompt and consistent improvement of coronary flow velocity reserve following successful recanalization of the coronary chronic total occlusion in patients with viable myocardium

Milan Dobrić ,Dragana Šobić Šaranović ,Milorad Tešić ,Stefan Juričić ,Ana Djordjević Dikić ,Olga Petrović ,Goran Stanković ,Milan Nedeljković ,Dragan Simić ,Dejan Orlić ,M Tomasević ,Ivana Jovanović ,Branko Beleslin,Jelena Rakočević ,Siniša Stojkovič ,Nikola Bošković ,Vojislav Giga,S Aleksandric ,Vladan Vukčević ,Miodrag Ostojić

doi:10.1186/s12947-020-00211-4

Abstract

BackgroundCoronary 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.MethodsOur 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.ResultsCollateral 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).ConclusionsIn 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.Trial registrationClinicalTrials.gov (Number NCT04060615).

Highlights

Coronary chronic total occlusion (CTO) is defined as the complete occlusion of coronary artery with no epicardial blood flow in the occluded arterial segment, lasting more than three months [1,2,3,4]
In patients with viable myocardium, prompt and significant coronary flow velocity reserve (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
Werner et al [11] have shown that about 50% of patients after successful CTO opening still have microvascular dysfunction defined as invasive CFVR < 2.0, which improved over time in additional 50% of them

Summary

Introduction

Coronary chronic total occlusion (CTO) is defined as the complete occlusion of coronary artery with no epicardial blood flow in the occluded arterial segment, lasting more than three months [1,2,3,4] It is characterized by the presence of more or less developed collateral blood vessels, and variable amount of viable myocardium in the perfusion territory of occluded artery [5, 6]. 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

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