Coronary flow velocity reserve in donor artery and myocardial performance index after successful recanalization of chronic total coronary occlusions

Abstract

Background: Percutaneous recanalization of chronic total coronary occlusion (CTO) tends to show a positive effect on left ventricular remodeling and ejection fraction (LVEF). Coronary flow velocity reserve (CFVR) is an important diagnostic index of the functional capacity of coronary arteries. The aim of this study was to evaluate, by non-invasive CFVR, whether the blood flow of donor artery reverts to normal after CTO percutaneous coronary intervention (PCI). Also, we assessed the effects of CTO recanalization on global cardiac functions by using myocardial performance index (MPI).

Methods: We evaluated 25 patients (mean age, 57.5 ± 14.1 years) who underwent CTO-PCI of the right coronary artery, whose collaterals were provided by the left anterior descending (LAD) artery. The coronary flow velocities in the distal LAD were measured using transthoracic echocardiography (TTE) before, 24 hours after, and within 3 months of PCI. Both two-dimensional and tissue Doppler (tD) echocardiography were used to calculate MPI.

Results: CFVR at month 3 was significantly increased compared to the basal and early CFVR (1.8 ± 0.3 vs. 2.3 ± 0.3 [P<.001] and 1.8 ± 0.2 vs. 2.3 ± 0.3 [P<.001], respectively). MPI at month 3 was significantly decreased compared to the basal and early MPI (0.61 ± 0.09 vs. 0.53 ± 0.07 [P<.001] and 0.60 ± 0.08 vs. 0.53 ± 0.07 [P<.001], respectively). Also, tD-MPI within 3 months was significantly decreased (0.58 ± 0.9 vs. 0.53 ± 0.8 [P=.01] and 0.57 ± 0.07 vs. 0.53 ± 0.8 [P<.001], respectively, for tD-MPI septal and 0.59 ± 0.08 vs. 0.51 ± 0.07 [P<.001] and 0.58 ± 0.08 vs. 0.51 ± 0.07 [P<.001], respectively, for tD-MPI lateral).

Conclusion: Successful recanalization of CTO results in increased CFVR-indicated blood flow in the donor artery and MPI-indicated global cardiac functions.