BACKGROUNDCoronary revascularization guided by fractional flow reserve (FFR) is associated with better patient outcomes after the procedure than revascularization guided by angiography alone. It is unknown whether the instantaneous wave-free ratio (iFR), an alternative measure that does not require the administration of adenosine, will offer benefits similar to those of FFR. METHODSWe randomly assigned 2492 patients with coronary artery disease, in a 1:1 ratio, to undergo either iFR-guided or FFR-guided coronary revascularization. The primary end point was the 1-year risk of major adverse cardiac events, which were a composite of death from any cause, nonfatal myocardial infarction, or unplanned revascularization. The trial was designed to show the noninferiority of iFR to FFR, with a margin of 3.4 percentage points for the difference in risk. RESULTSAt 1 year, the primary end point had occurred in 78 of 1148 patients (6.8%) in the iFR group and in 83 of 1182 patients (7.0%) in the FFR group (difference in risk, −0.2 percentage points; 95% confidence interval [CI], −2.3 to 1.8; P<0.001 for noninferiority; hazard ratio, 0.95; 95% CI, 0.68 to 1.33; P = 0.78). The risk of each component of the primary end point and of death from cardiovascular or noncardiovascular causes did not differ significantly between the groups. The number of patients who had adverse procedural symptoms and clinical signs was significantly lower in the iFR group than in the FFR group (39 patients [3.1%] vs. 385 patients [30.8%], P<0.001), and the median procedural time was significantly shorter (40.5 minutes vs. 45.0 minutes, P = 0.001). CONCLUSIONSCoronary revascularization guided by iFR was noninferior to revascularization guided by FFR with respect to the risk of major adverse cardiac events at 1 year. The rate of adverse procedural signs and symptoms was lower and the procedural time was shorter with iFR than with FFR. ( Use of Instantaneous Wave-free R atio in PCI F or the past 20 years, physiological measurements obtained during invasive procedures have been used to guide coronary revascularization. Pioneering work supported the use of flow measurements to make safe decisions about revascularization, 1,2 but this approach was soon superseded by the use of fractional flow reserve (FFR), which measures pressure as a surrogate of flow to estimate the severity of stenosis. 3-5 FFR was successful largely because of its technical simplicity and because clinical trials showed that it was associated with improved clinical outcomes after percutaneous coronary intervention (PCI). 6,7 Consequently, FFR is now included in the appropriate-use criteria for coronary angiography and in the American College of Cardiology-American Heart Association-European Society of Cardiology guidelines; despite these recommendations, its adoption remains limited. [8][9][10] FFR must be measured during maximal hyperemia, which is typically induced with the administration of a potent intravenous or intracoronary vasodilator, such as adenosine. 11 Several studies have...

Background No previous reports have described the comprehensive care pathways involved in chronic total occlusion percutaneous coronary intervention (CTO PCI). Methods In a study of 1,000 consecutive patients undergoing CTO PCI using hybrid approach, a systematic algorithm of selecting CTO PCI strategies, the procedural characteristics, complication rates, and patient reported health status outcomes through 12 months were assessed. Results Technical success of the index CTO PCI was 86%, with 89% of patients having at least one successful CTO PCI within 12 months. A total of 13.8% underwent CTO PCI of another vessel or reattempt of index CTO PCI within 1 year. At 1 year, the unadjusted major adverse cardiac and cerebral event (MACCE) rate was lower in patients with successful index CTO PCI compared to patients with unsuccessful index CTO PCI (9.4% vs. 14.6%, p = .04). The adjusted hazard ratios of myocardial infarction and death at 12 months were numerically lower in patients with successful index CTO PCI, compared to patients with unsuccessful index CTO PCI. Patients with successful index CTO PCI reported significantly greater improvement in health status throughout 12‐months compared to patients with unsuccessful index CTO PCI. Conclusion CTO‐PCI in the real‐world often require treatment of second CTO, non‐CTO PCI or repeat procedures to treat initially unsuccessful lesions. Successful CTO PCI is associated with numerically lower MACCE at 1 year and persistent symptomatic improvement compared to unsuccessful CTO PCI. Understanding the relationship between the care pathways following CTO PCI and health status benefit requires further study.

Overall, deferral of revascularization is equally safe with both iFR and FFR, with a low MACE rate of about 4%. Lesions were more frequently deferred when iFR was used to assess physiological significance. In deferred patients presenting with ACS, the event rate was significantly increased compared with SAP at 1 year.

Clarifying the success rates, risks, and benefits of CTO PCI will help to more accurately contextualize the informed consent process for these procedures so that patients with appropriate indications for CTO PCI can more effectively share in the decision to pursue this or other therapeutic options.