Combined Anatomic and Functional Testing Identifies Patients With Obstructive Coronary Artery Disease Who Benefit From Revascularization.

BACKGROUND

In patients with obstructive coronary artery disease, early revascularization does not improve outcomes but may reduce angina symptoms. The objective of this study was to examine whether changes in health status outcomes following revascularization are explained by the extent of myocardial perfusion defects and improvement in myocardial perfusion.

METHODS

Two trials enrolling stable patients with new-onset chest pain suggestive of obstructive coronary artery disease, the ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) and the Dan-NICAD (Danish Study of Noninvasive Testing in Coronary Artery Disease) trials, were analyzed. Patients with single-vessel coronary artery disease who underwent nuclear myocardial perfusion imaging (nMPI) were included. In the ISCHEMIA trial, patients with moderate/severe ischemia were randomized to either optimal medical therapy alone or optimal medical therapy and invasive angiography. The Dan-NICAD trial enrolled patients with suspected stenosis on coronary computed tomographic angiography undergoing nMPI. Test-guided revascularization blinded to nMPI was performed, and patients with initially abnormal nMPI were reassessed after 12 months. The primary outcome was the change in the Seattle Angina Questionnaire angina frequency score.

RESULTS

In total, 584 patients were eligible. In patients with a summed difference score of 5≤10 (n=149 [25%]) and ≥10 (n=152 [26%]), revascularization was associated with an improved angina frequency score (mean change ±SD: 16.4±20.9 and 19.0±24.1). No improvement was demonstrated in patients with a summed difference score <5. In multivariable logistic regression analysis (n=91), an increase in hyperemic myocardial blood flow at follow-up was associated with freedom from angina (odds ratio, 2.89 [95% CI, 1.04-8.70]).

CONCLUSIONS

In patients with single-vessel coronary artery disease, nMPI may identify patients more likely to experience improved symptoms from revascularization, potentially reflecting enhanced myocardial perfusion.