A clinical study on the effect of open chronic total occlusion on hemodynamics of collateral circulation donor.

OBJECTIVE

This study applied pressure measurement to measure the hemodynamic changes in right coronary artery (RCA) donor vessels before and after the opening of the vessel in patients with left anterior descending chronic total occlusion (LAD-CTO) interventional therapy.

METHODS

A total of 45 patients with LAD-CTO were divided into two groups of percutaneous coronary intervention (PCI) to observe the hemodynamic changes (fractional flow reserve [FFR] and instantaneous wave-free ratio [iFR]) before and after opening the chronic total occlusion (CTO), in order to provide collateral circulating donor vessels to the CTO, and observe the changes in iFR and FFR. The results of these two measures were compared to determine the significance of the donor vascular function.

RESULTS

A total of 45 patients with LAD-CTO successfully underwent LAD-CTO interventional therapy, and were immediately measured for FFR and iFR of the donor vessels. The FFR changes before right coronary artery flow reserve (RCAFR) was 0.73±0.083, and after the operation, this was 0.77±0.073. The iFR changes before RCAFR was 0.90±0.048, and after the operation, this was 0.93±0.034. Before and after the opening of the RCA, the FFR change (ΔFFR) and iFR change (ΔiFR) were also correlated with r = 0.033 (0.041-0.568: P < 0.05). A total of 19 cases had a FFR value of <0.75 before the operation, and the average FFR before and after the PCI was 0.65±0.048 and 0.72±0.057, respectively. Furthermore, the ΔFFR was 0.076±0.057 (n = 19), and FFR was >0.75 in 26 cases. The ΔFFR was 0.017±0.0088 (n = 26). These two groups were compared, P = 0.0032 (P < 0.05).

CONCLUSION

The FFR and iFR results were the same in terms of RCA hemodynamic changes, after the LAD-CTO was opened. For the RCA with a preoperative FFR of <0.75, the increase in RCAFR after LAD-CTO PCI was more obvious.