FIRE Trial Shows Benefit of Physiology-Guided Complete Revascularization in MI Patients Aged ≥ 75 Years

August 26, 2023—The European Society of Cardiology (ESC) announced findings from a study showing that physiology-guided complete revascularization reduces ischemic events compared with culprit-only revascularization in myocardial infarction (MI) patients aged ≥ 75 years with multivessel disease.

The FIRE trial enrolled 1,445 patients (median age, 80 years; women, 36.5%) at 34 sites in Italy, Spain, and Poland.

Principal Investigator Simone Biscaglia, MD, of University Hospital Santa Anna in Ferrara, Italy, presented the late-breaking research in a Hot Line session at the ESC Congress 2023 held August 25-28 in Amsterdam, the Netherlands.

As noted in the ESC press release, acute coronary syndrome patients aged ≥ 75 years are often underrepresented in clinical trials, and management is challenging due to lack of robust evidence. For example, the impact of complete revascularization, which is well established in younger patients, is uncertain in older patients, who have a higher risk of complications. Guidelines reflect this lack of data, with no specific recommendations on the type of revascularization for older MI patients with multivessel disease.

ESC guidelines state that routine revascularization of nonculprit lesions should be considered in ST-segment elevation MI (STEMI) patients with multivessel disease before hospital discharge. For non-STEMI (NSTEMI) patients, ESC guidelines recommend applying the same interventional strategies in older patients as for younger patients.

To address this knowledge gap, the FIRE trial examined whether complete revascularization based on coronary physiology is superior to a culprit-only strategy in older patients with MI and multivessel disease.

Patients were eligible for enrollment in FIRE if they were aged ≥ 75 years, had been admitted to the hospital with STEMI or NSTEMI, had undergone successful percutaneous coronary intervention (PCI) of the culprit lesion, and had multivessel disease with at least one lesion in a nonculprit coronary artery with a minimum vessel diameter of 2.5 mm and a visually estimated diameter stenosis of 50% to 99%.

As summarized in the ESC press release, after successful treatment of the culprit lesion, patients were randomized to culprit-only treatment or to physiology-guided complete revascularization. Patients in the physiology-guided complete revascularization group received (1) physiologic assessment using wire-based and angiography-based measurements and (2) PCI of all functionally significant nonculprit lesions.

Both physiologic assessment and PCI of nonculprit lesions were allowed during either the index intervention or in a staged procedure within the index hospitalization. Patients in the culprit-only revascularization group did not undergo any physiologic assessment or revascularization of nonculprit lesions.

The primary outcome was a composite of death, MI, stroke, or ischemia-driven coronary revascularization occurring within 1 year of randomization.

A key secondary outcome was the 1-year composite endpoint of cardiovascular death or MI. Other secondary outcomes included the individual components of the primary outcome.

The safety outcome was a composite of contrast-associated acute kidney injury, stroke, or bleeding (Bleeding Academic Research Consortium type 3 or 5) within 1 year of randomization.

According to the ESC press release, the FIRE investigators reported the following:

• The primary outcome occurred in 113 patients (15.7%) in the physiology-guided complete revascularization group and 152 patients (21%) in the culprit-only group (hazard ratio [HR], 0.73; 95% CI, 0.57-0.93; P = .01). The number of patients needed to treat to prevent the occurrence of one primary outcome event was 19.
• The key secondary outcome of cardiovascular death or MI appeared to be lower in the physiology-guided complete revascularization group (HR, 0.64; 95% CI, 0.47-0.88). The number of patients needed to treat to prevent one cardiovascular death or MI was 22.
• Each component of the primary outcome—with the exception of stroke—appeared to be lower in the physiology-guided complete revascularization group, including death (HR, 0.70; 95% CI, 0.51-0.96). The number of patients needed to treat to prevent one death was 27.
• There was no apparent difference between the two groups in the incidence of the composite safety outcome, with an HR of 1.11 for physiology-guided complete revascularization versus culprit-only revascularization (95% CI, 0.89-1.37; P = .37).

“The FIRE trial provides much-needed data on the safety and efficacy of physiology-guided complete revascularization in older MI patients with multivessel disease,” commented Dr. Biscaglia in the ESC press release. “The reduction of the primary endpoint with physiology-guided complete revascularization was mainly driven by hard endpoints such as death and MI. The results suggest that in older MI patients with multivessel disease, complete revascularization guided by physiology should be routinely pursued.”