Revascularization decisions in patients with chronic coronary syndromes: Results of the second International Survey on Interventional Strategy (ISIS-2)

Background: In chronic coronary syndromes, guidelines mandate invasive functional guidance of revascularization whenever non-invasive proof of ischemia is missing. ISIS-2 survey aimed to evaluate how the adoption of guideline recommendation on ischemia-guided revascularization has evolved over the last 5–7 years. Methods: In ISIS-2 participants assessed five complete angiograms, presenting only intermediate stenoses without information on non-invasive pre-testing. Fractional flow reserve was known for each stenosis, but remained undisclosed. Participants could determine stenosis significance either by angiography or by requesting an adjunctive invasive diagnostic method (intravascular imaging or functional tests). Primary endpoint was the rate of requesting adjunctive functional assessment. Secondary endpoints were the rate of concordance between angiography-based decisions and know functional severity. ISIS-2 utilized the same web-based platform as ISIS-1 in 2013. (NCT04001452). Results: 334 participants performed 2059 lesion evaluations: 1202 (59%) decisions were based solely on angiography without expressed need for further evaluation. These decisions were discordant with known functional significance in 39%, mainly with potential of overtreatment. Participants requested invasive functional assessment in 643 (31%) and intravascular imaging in 214 (10%) cases. Compared to ISIS-1 the rate of purely angiography-based decisions has decreased (59% vs 66%; p < 0.001), while invasive functional tests were more frequently requested (31% vs 25%; p < 0.001). Conclusions: ISIS-2 suggests an evolving pattern in the intention to integrate invasive coronary physiology into the revascularization decisions. However, the disconnect between recommendations and current thinking is still dominant.