Serial Fractional Flow Reserve Measurements Post Coronary Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND: The aim of this study was to evaluate the functional result of chronic total occlusion percutaneous coronary intervention (PCI) measured by fractional flow reserve (FFR) immediately post the index procedure and at short-term follow-up. METHODS AND RESULTS: This was a prospective single-center observational study. Consecutive patients with right coronary artery chronic total occlusion scheduled for elective PCI were included. FFR measurements were performed immediately after successful PCI and at 4 months follow-up. Twenty-six patients completed baseline and follow-up measurements. Mean age was 61.2 +/- 9.7 years, 88.5% of the patients were male, and 19.2% were diabetic. The mean FFR immediately after successful chronic total occlusion PCI was 0.82 +/- 0.10 and significantly increased to 0.89 +/- 0.07 at 4 months (P<0.001). The FFR increased in 77% of the patients with a mean absolute increase of 0.07 +/- 0.08. The incidence of FFR <= 0.80 immediately after PCI was significantly higher amongst patients with subintimal versus intraplaque recanalization (23% versus 12%; P=0.03). At 4 months, FFR <= 0.80 was found only in 2 patients with subintimal recanalization. At follow-up, 42.7% of the patients continued to have an FFR <0.90. CONCLUSIONS: Post chronic total occlusion PCI, FFR increased significantly at short-term follow-up compared with measurements post index procedure. Because FFR remained <0.90 in many cases, further efforts should be made to optimize procedural results.