BACKGROUND AND OBJECTIVES: Outcomes of deferring percutaneous coronary intervention (PCI) without invasive physiologic assessment for intermediate coronary lesions is uncertain. We sought to compare long-term outcomes between medical treatment and PCI of intermediate lesions without invasive physiologic assessment. METHODS: A total of 899 patients with intermediate coronary lesions between 50% and 70% diameter-stenosis were randomized to the conservative group (n=449) or the aggressive group (n=450). For intermediate lesions, PCI was performed in the aggressive group, but was deferred in the conservative group. The primary endpoint was major adverse cardiac events (MACE, a composite of all-cause death, myocardial infarction [MI], or ischemia-driven any revascularization) at 3 years. RESULTS: The number of treated lesions per patient was 0.8±0.9 in the conservative group and 1.7±0.9 in the aggressive group (p=0.001). At 3 years, the conservative group had a significantly higher incidence of MACE than the aggressive group (13.8% vs. 9.3%
hazard ratio [HR], 1.49
95% confidence interval [CI], 1.00-2.21
p=0.049), mainly driven by revascularization of target intermediate lesion (6.5% vs. 1.1%
HR, 5.69
95% CI, 2.20-14.73
p<
0.001). Between 1 and 3 years after the index procedure, compared to the aggressive group, the conservative group had significantly higher incidence of cardiac death or MI (3.2% vs. 0.7%
HR, 4.34
95% CI, 1.24-15.22
p=0.022) and ischemia-driven any revascularization. CONCLUSIONS: For intermediate lesions, medical therapy alone, guided only by angiography, was associated with a higher risk of MACE at 3 years compared with performing PCI, mainly due to increased revascularization. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00743899.