Complete revascularization based on angiography derived fractional flow reserve versus incomplete revascularization in patients with ST-segment elevation myocardial infarction

BACKGROUND

Nearly half of ST-segment elevation myocardial infarction (STEMI) patients present with significant multivessel coronary artery disease, they are at high risk of subsequent adverse events. Whether complete revascularization guided by coronary angiography-derived fractional flow reserve (caFFR) further reduces such events risk is not fully investigated.

METHODS

In this study, 367 consecutive STEMI patients who underwent successful primary percutaneous coronary intervention (PCI) were enrolled. caFFR of all three coronary vessels were measured, including 367 culprit vessels and 703 non-culprit vessels. Complete revascularization was defined as post-PCI caFFR > 0.8 of all three coronary vessels. The primary endpoint was major adverse cardiovascular events (MACE, a composite of cardiovascular death, non-fatal recurrent myocardial infarction, ischemia-driven revascularization and non-fatal stroke/transient ischemic attacks) during follow-up.

RESULTS

At a median follow-up of 3.8 years, MACE had occurred in 39 patients of the 220 (17.7%) in the complete revascularization group as compared with 49 patients of the 131 (37.4%) in the incomplete revascularization group (hazard ratio [HR] 1.9; 95% confidence interval [CI] 1.2-3.0; p = 0.005). The incomplete revascularization in culprit vessels evaluated by caFFR showed the highest risk for MACE occurrence.

CONCLUSIONS

In STEMI patients with multivessel coronary artery disease, incomplete revascularization based on caFFR might contribute to identifying patients at high-risk.

Prognostic Value of Coronary Angiography-Derived Fractional Flow Reserve Immediately After Stenting

Objectives

The aim of this study was to investigate the potential prognostic value of post-percutaneous coronary intervention (PCI) angiography-derived fractional flow reserve (FFR) and its gradient across the stent.

Background

Post-PCI FFR and its gradient across the stent have been proved to be associated with clinical outcomes. However, little is known about the prognostic value of post-PCI coronary angiography-derived FFR and its gradient across the stent.

Methods

Patients diagnosed with coronary heart disease and participated in drug-eluting stent (DES) clinical trials for stent implantation in a single center were included for this retrospective analysis. A novel coronary angiography-derived FFR (caFFR) and its gradient across the stent were calculated offline using two projections from coronary angiography performed after PCI. Clinical follow-up was completed at 9 months after the index procedure and the primary outcome was target vessel failure (TVF), defined as a composite of target vessel-related myocardial infarction (MI), target vessel-related revascularization (TVR), and cardiac death. Coronary angiography was also performed at the 9 months follow-up time to get data of late lumen loss (LLL) and percent diameter stenosis (%DS).

Results

A total of 159 vessels in 136 patients were analyzed. The mean value of post-PCI caFFR was 0.90 ± 0.06. The median value of trans-stent caFFR gradient (ΔcaFFR_stent) was 0.04 (interquartile range 0.02-0.08). ΔcaFFR_stent>0 was demonstrated in 147 vessels (92.45%). The TVF rate was significantly higher in patients with post-PCI caFFR < 0.90 (4 [8.16%] vs. 1 [1.15%], P = 0.037), which was mainly achieved by the difference between the TVR rate. In the subgroup with lesions located in the left anterior descending coronary artery (LAD), post-PCI caFFR was an independent predictor of LLL (β = -1.07, 95% CI: -1.74 to -0.39, P = 0.002) and %DS at follow-up (β = -30.24, 95% CI: -56.44 to -4.04, P = 0.025), ΔcaFFR_stent was an independent predictor of LLL (β=0.98, 95% CI:0.13-1.83, P = 0.026).

Conclusion

Suboptimal post-PCI caFFR and trans-stent caFFR gradient were common among vessels immediately after stenting. Lower post-PCI caFFR was associated with a higher rate of 9-month TVF. After LAD PCI, both post-PCI caFFR and its gradient across stent were independent predictors of the neointimal proliferation of the target vessel evaluated by LLL and %DS at follow-up.

Agreement of Angiography-Derived and Wire-Based Fractional Flow Reserves in Percutaneous Coronary Intervention

Background: Coronary angiography-derived fractional flow reserve (caFFR) measurements have shown good correlations and agreement with invasive wire-based fractional flow reserve (FFR) measurements. However, few studies have examined the diagnostic performance of caFFR measurements before and after percutaneous coronary intervention (PCI). This study sought to compare the diagnostic performance of caFFR measurements against wire-based FFR measurements in patients before and after PCI.

Methods: Patients who underwent FFR-guided PCI were eligible for the acquisition of caFFR measurements. Offline caFFR measurements were performed by blinded hospital operators in a core laboratory. The primary endpoint was the vessel-oriented composite endpoint (VOCE), defined as a composite of vessel-related cardiovascular death, vessel-related myocardial infarction, and target vessel revascularization.

Results: A total of 105 pre-PCI caFFR measurements and 65 post-PCI caFFR measurements were compared against available wire-based FFR measurements. A strong linear correlation was found between wire-based FFR and caFFR measurements (r = 0.77; p < 0.001) before PCI, and caFFR measurements also showed a high correlation (r = 0.82; p < 0.001) with wire-based FFR measurements after PCI. A total of 6 VOCEs were observed in 61 patients during follow-up. Post-PCI FFR values (≤0.82) in the target vessel was the strongest predictor of VOCE [hazard ratio (HR): 5.59; 95% confidence interval (CI): 1.12–27.96; p = 0.036). Similarly, patients with low post-PCI caFFR values (≤0.83) showed an 8-fold higher risk of VOCE than those with high post-PCI caFFR values (>0.83; HR: 8.83; 95% CI: 1.46–53.44; p = 0.017).

Conclusion: The study showed that the caFFR measurements were well-correlated and in agreement with invasive wire-based FFR measurements before and after PCI. Similar to wire-based FFR measurements, post-PCI caFFR measurements can be used to identify patients with a higher risk for adverse events associated with PCI.