Background: Current clinical guidelines recommend considering both obstructive and nonobstructive causes of myocardial ischemia in patients with chronic coronary syndrome. Wire-based physiological assessment constitutes a valid approach for this purpose, but it remains underutilized. We evaluated the diagnostic yield and clinical impact of an alternative wire-free approach for this purpose.
Methods: This is a subanalysis of the multicenter, prospective AID-ANGIO study (Advanced Invasive Diagnosis for Patients with Chronic Coronary Syndromes Undergoing Coronary Angiography), evaluating the impact of a wire-free advanced invasive diagnosis (AID) strategy in the diagnostic workflow of patients with chronic coronary syndrome admitted to the catheterization laboratory. The wire-free AID strategy combined quantitative flow ratio for epicardial evaluation, contrast angiography-derived index of coronary microcirculatory resistance for microvascular assessment, and acetylcholine testing for the endothelial-dependent coronary function.
Results: The study included 262 patients. The wire-free AID strategy identified a cause of myocardial ischemia in 84.3% of patients, representing a 2-fold increase in the identification of a cause of myocardial ischemia, compared with coronary angiography alone (P<0.0001). In addition, the wire-free AID strategy demonstrated substantial agreement compared with the wire-based AID strategy (Cohen κ 0.78). The wire-free AID strategy led to a change in the initial therapeutic plan in 55.3% of patients compared with coronary angiography. Nevertheless, the wire-free AID strategy maintained good concordance with the wire-based AID strategy (16.8% of therapeutic changes).
Conclusions: This study supports the clinical utility of a wire-free AID strategy in patients with chronic coronary syndrome, demonstrating its potential to improve diagnostic yield and guide clinical decision-making compared with coronary angiography alone. In addition, it shows substantial agreement with the wire-based approach.
Keywords: acetylcholine; coronary artery disease; fractional flow reserve; microcirculation; quantitative flow ratio.