Long-term outcomes after deferral of revascularization of in-stent restenosis using fractional flow reserve

Objectives: To investigate the outcomes of deferred coronary revascularization in patients with non-significant in-stent restenosis (ISR) by physiological assessment.

Background: The pathophysiology and natural history of ISR is markedly different from de-novo stenoses. There is a paucity of data on the safety of deferral of revascularization of ISR using physiological assessment.

Methods: In this single centre study, using a propensity-score matched analysis, we compared the long-term clinical outcomes of patients with ISR and de-novo disease deferred based on intracoronary physiology. Matching was on a 1:2 basis of ISR to de-novo stenosis. The primary end point was major adverse cardiovascular events (MACE) a composite of all-cause mortality, target lesion revascularization or target vessel myocardial infarction at 36 months.

Results: Matched cohorts of 56 ISR and 112 de-novo stenoses were analyzed. The median percentage stenosis was 50% in both groups (p = 0.403). Deferral was based on fractional flow reserve (FFR). The mean FFR was 0.86 across both groups (p = 0.942). At 36-months, freedom from MACE was similar between groups; 86.2% versus 92.8% log rank p=0.180 for ISR and de-novo lesions, respectively. Neither were there differences in the individual components of MACE.

Conclusions: Deferral of coronary revascularization in patients with ISR based on its functional impact is associated to similar long-term safety as in de-novo coronary stenosis.