Physiological evaluation of the provisional side-branch intervention strategy for bifurcation lesions using instantaneous wave-free ratio

BACKGROUND: The provisional side-branch intervention strategy remains the gold standard approach for repair of coronary bifurcation lesions. We performed this study to evaluate the clinical and functional outcomes of using the instantaneous wave-free ratio (iFR) for physiological assessment in provisional side-branch repair of bifurcation lesions. METHODS: Fifty patients with coronary bifurcation lesions were equally divided into two groups: (I) an iFR-guided side-branch intervention group and (II) a conventional group, in which the operator selected a different interventional method. After the procedure, we performed a six-month follow-up for postoperative ejection fraction (EF) and clinical cardiac outcomes. RESULTS: Our results showed that the iFR measurement procedure was technically feasible in bifurcation lesions, with no procedural-related complications. Moreover, measuring iFR significantly predicted the side-branch percent stenosis after stenting of the main branch (r = −0.81, p < 0.0001). Compared to the conventional group, the iFR-guided group showed a significantly shorter procedural time (MD = −14.6 min, 95% CI [−27.7, −1.4]) and hospital stay duration (MD = −0.92 days, 95% CI [−1.6, −0.28]). However, no significant differences were recorded between the iFR-guided and conventional groups in terms of postoperative EF (p = 0.9), six-month heart failure class (p = 0.89), or post-interventional angina (p = 0.066). CONCLUSION: Using iFR for physiological assessment during the provisional side-branch intervention strategy can reduce the procedural time and length of hospital stay in patients with bifurcation lesions. Larger trials should compare the clinical outcomes of iFR to other physiological assessment methods such as the fractional flow reserve (FFR) in patients with coronary bifurcation lesions. ClinicalTrials.gov number: NCT02785510