Dynamic Changes of 3D Bending Angle Through the Cardiac Cycle: Implications With Bioresorbable Scaffold Performance.

Abstract

Background: Several predictors of adverse events following bioresorbable scaffold (BRS) percutaneous coronary intervention (PCI) have been identified. The role of vessel biomechanical properties remains underexplored.

Objectives: This study aimed to describe the biomechanical properties of coronary arteries after BRS implantation by assessing the maximum bending angle (BAmax) changes through the cardiac cycle and their interaction with long-term incidence of target-vessel failure (TVF).

Methods: Three-dimensional BAmax was computed at end-diastole and end-systole, before and after BRS implantation. Cardiac motion-induced angulation change (ΔcBAmax) was calculated as the absolute difference between end-systole and end-diastole, and scaffold-induced angulation changes as the absolute difference between pre- and postimplantation.

Results: BAmax computation was available in 164 coronary vessels at baseline and in 88 at long-term follow-up (57 [42-66] months). Following BRS implantation, BAmax decreased both in diastole (-6.2°) and in systole (-9.0°). TVF-related vessels showed higher pre-PCI BAmax at end-diastole, at end-systole, and higher ΔcBAmax (11.4° [6.0°-22.9°] vs 5.8° [2.7°-12.4°]; P = 0.002), whereas no significant difference in post-PCI BAmax was present. Scaffold-induced BAmax change was significantly higher in vessels with TVF compared with TVF-free ones, both at end-diastole, end-systole, and in the ΔcBAmax group (10.1° [4.4°-20.6°] vs 5.7° [2.3°-10.9°]; P = 0.001). Multivariate analysis identified scaffold-induced change in ΔcBAmax as an independent predictor of TVF (for 10° increase: aHR 1.65; 95% CI: 1.11-2.45; P = 0.01). After BRS resorption, coronary artery BAmax increased, restoring baseline biomechanics.

Conclusions: BA changes through the cardiac cycle decrease after PCI with BRS; the greater the decrease, the higher the risk of target vessel failure at follow-up.