Angiographic diameter stenosis (DS) is the most widely used criteria to perform percutaneous coronary intervention in daily practice. While DS between 50 and 70 percent has been termed an "intermediate stenosis," the clinical outcome of PCI based on the angiographic criteria of 50 percent or 70 percent has never been studied.

The SMART-CASE trial evaluated the relative efficacy and safety of a conservative revascularization strategy for intermediate stenoses compared to a more aggressive approach of anatomical complete revascularization in the treatment of coronary stenosis. The investigator-initiated, multicenter, open label, prospective trial randomized 899 patients undergoing coronary angiography to be evaluated for PCI based on a conservative strategy (revascularization of DS>70 percent) or an aggressive strategy (DS>50 percent). The primary endpoint was a composite of all cause death, myocardial infarction or any revascularization at one year.

After one year, both the conservative strategy group and aggressive strategy group had similar rates of adverse events (7.3 percent vs. 6.8 percent, respectively). Rates for all cause death (0.5 percent vs. 2.1 percent), myocardial infarction (0.9 percent in each group) and any revascularization (6.8 percent vs. 4.8 percent) were also similar, demonstrating the non-inferiority of the conservative strategy.

"Conservative revascularization using criteria of 70 percent diameter stenosis was found to be non-inferior to aggressive revascularization," said the lead investigator Hyeon-Cheol Gwon, MD, PhD. Dr. Gwon is a Professor at the Samsung Medical Center in Seoul, South Korea.

"These results demonstrate that revascularization of angiographically intermediate lesions can be safely deferred."