Functional Coronary Angiography Improves Outcomes in STEMI With Multivessel Disease

Clinicians must decide which non-culprit lesions to stent during complete revascularization, yet visual angiography can drive unnecessary interventions and excess contrast exposure. These choices influence recurrent ischemia and procedure-related harm in a high-risk population. To help address this challenge, investigators have evaluated functional coronary angiography to guide treatment decisions after primary percutaneous coronary intervention.

Functional coronary angiography reconstructs the coronary tree in three dimensions from routine angiographic images obtained during the culprit-lesion procedure. It estimates blood flow to indicate which additional blockages meaningfully limit perfusion and warrant treatment. Investigators from University Hospital of Ferrara, Italy, described the approach as a way to move beyond purely visual assessment and target only clinically important non-culprit lesions.

The investigator-initiated AIR-STEMI randomized trial tested this strategy across 21 centers in Italy and Pakistan. The study enrolled 1,823 patients with ST-segment elevation myocardial infarction and multivessel disease who had undergone successful treatment of the culprit lesion. Participants were randomized to complete revascularization guided by either functional coronary angiography or conventional angiography.

In the functional-guidance arm, all qualifying non-culprit lesions were assessed using angiography-derived fractional flow reserve. Lesions with values greater than 0.80 were deferred, while those with values of 0.80 or lower underwent percutaneous coronary intervention. In the angiography-guided arm, intervention was recommended for all non-culprit lesions showing at least 50% stenosis on conventional angiography. This approach led to intervention in 51.9% of non-culprit vessels with functional guidance compared with 94.9% with angiography guidance, along with fewer procedures, fewer treated vessels, shorter treated segments, and less contrast use.

At a median follow-up of 17.9 months, the composite of all-cause death, myocardial infarction, cerebrovascular accident, or ischemia-driven revascularization occurred less often with functional guidance than with angiography guidance, at 8.9% versus 13.7% (hazard ratio 0.62; 95% confidence interval 0.47–0.83; p<0.001). Procedure-related and spontaneous myocardial infarction, as well as repeat revascularization, were significantly reduced. All-cause mortality was similar between groups, at 3.9% versus 5.1%.

Safety outcomes also favored functional guidance. Contrast-associated acute kidney injury or major bleeding was less frequent with functional coronary angiography than with conventional angiography, 4.6% versus 7.1% (hazard ratio 0.63; 95% confidence interval 0.43–0.93; p=0.02). Findings were presented in a Hot Line session at ESC Congress 2026 and published simultaneously in the New England Journal of Medicine.

“Functional coronary angiography allowed us to select and treat only those non-culprit lesions that were clinically important, reducing unnecessary procedures and the risk of complications,” said Simone Biscaglia, associate professor, University Hospital of Ferrara, Italy.

“By moving beyond visual estimation alone, this approach brings complete revascularization closer to precision medicine: treating the lesions that matter while avoiding unnecessary PCI in lesions that do not appear to limit blood flow. These results support functional coronary angiography as a new strategy to make complete revascularization more selective, safer and more personalized in this high-risk population,” said Biscaglia.

Related Links
European Society of Cardiology