Post-PCI outcomes predicted by residual quantitative flow ratio derived from coronary CT angiography -A bi-center...

This study investigates the concordance between residual quantitative flow ratio derived from coronary CT angiography (CCTA) (residual CT-μFR) and post-percutaneous coronary intervention (post-PCI) Murray law-based quantitative flow ratio (μQFR) values, and evaluates the prognostic value of residual CT-μFR for post-PCI outcomes.

This bi-center retrospective study included patients who underwent CCTA before achieving complete revascularization through successful PCI with stent implantation. Residual CT-μFR and post-PCI μQFR were calculated from acquired projections. The location of CT-μFR lesions was matched with the corresponding PCI location to simulate the performed intervention and enable the computation of residual CT-μFR. The primary endpoint was the vessel-oriented composite endpoint (VOCE), defined as the composite of vessel-related cardiovascular death, vessel-related myocardial infarction (MI), and ischemia-driven target vessel revascularization (ID-TVR).

This study enrolled 170 patients with 202 vessels analyzed, 65.2 % of the patients were male. The median follow-up duration was 1125.5 days (662.7, 1642.0 days). The median value of post-PCI μQFR was 0.95 (0.91, 0.97). The residual CT-μFR and post-PCI μQFR were strongly correlated (ρ = 0.80, ICC = 0.88, p < 0.001). Receiver operating characteristic (ROC) curve analysis established an optimal residual CT-μFR cutoff of 0.91 for predicting VOCE [area under the curve (AUC): 0.82; 95 % CI: 0.74-0.90; p < 0.001]. Multivariate analysis identified diameter stenosis percentage (DS%), prior MI, and residual CT-μFR ≤ 0.91 as significant predictors of VOCE. The residual CT-μFR was significantly lower in vessels with the VOCE during follow-up, compared with those without it [0.88 (0.85, 0.90) vs. 0.95 (0.94, 0.97), respectively; p < 0.001). After correction for potential confounding factors, the residual CT-μFR was associated with a 6-fold increase in risk for the VOCE (HR: 6.46; 95 % CI: 2.78 - 14.99; p < 0.001). Compared with residual CT-μFR > 0.91 group, the cumulative incidence of VOCE was significantly higher in residual CT-μFR ≤ 0.91 group (47.2 % vs. 5.4 %; HR: 9.67; 95 % CI: 4.45 to 20.98, p < 0.0001).

Residual CT-μFR is a feasible and effective tool for PCI optimization and risk stratification, enabling more informed decision-making to improve patient outcomes.