A new study finds that in patients with myocardial infarction (MI) and multivessel disease, physiology-guided complete revascularization was associated with a lower risk of a composite of death, MI, stroke, or ischemia-driven revascularization than culprit-only revascularization.

Results of the FIRE Trial, which were observed in patients 75 years of age or older and 1 year post-procedure, equated to a 27% lower relative risk compared to culprit-only revascularization.

“The benefit was driven by a reduction in each individual component of the composite outcome, with the exception of stroke,” said the authors of the manuscript, which was published Saturday online in The New England Journal of Medicine, simultaneous with the presentation at the European Society of Cardiology (ESC) congress 2023 in Amsterdam. “In addition, physiology-guided complete revascularization was associated with a 36% relative reduction in the composite outcome consisting of cardiovascular death or MI.”

Out of the 1,445 patients identified, a primary-outcome event (a composite of death, myocardial infarction, stroke, or any revascularization at 1 year) occurred in 113 patients (15.7%) in the complete-revascularization group.

A primary-outcome event occurred in a further 152 patients (21.0%) in the culprit-only group of the multicenter, randomized trial (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.57 to 0.93; P=0.01).

Cardiovascular death or MI occurred in 64 patients (8.9%) in the complete revascularization group and in 98 patients (13.5%) in the culprit-only group (HR, 0.64; 95% CI, 0.47 to 0.88). The safety outcome did not appear to differ between the groups (22.5% vs. 20.4%; P=0.37).

Older patient considerations

“Studies have shown that complete revascularization that is guided by angiography or physiological assessment is superior to the culprit-only strategy in younger and low-risk patients with STEMI [ST segment elevation myocardial infarction],” says the paper.

“This benefit is mainly driven by the reduction of recurrence of myocardial infarction or the need for repeated revascularization,” added the research team, led by Simone Biscaglia, MD, from the University Hospital of Ferrara in Cona, Italy. “However, older patients with myocardial infarction have unique clinical, anatomic, and procedural characteristics that were not captured by these studies.”

The research team’s observations were further discussed in a press conference at ESC, where Biscaglia commented on currently available registry data from the U.S. and Europe showing that more than 50% of patients 80 years and older were being treated with culprit-only revascularization.

“The percentage is much higher in developing countries than in countries from Europe and the U.S.,” he said. “But even in Europe and the U.S., the percentage of patients receiving culprit-only treatment is high.

When questioned about the merits of an angiography-guided strategy versus a physiology-based one, Biscaglia said the idea of the study was to treat the flow-limiting lesion because, in older patients, the team had a huge amount of data showing that periprocedural complications are more frequent and more impactful on prognosis.

“So, in the FIRE trial, 50% of non-culprit lesions were deemed visually important for the operator and amenable for treatment resulting in a negative and physiological assessment,” he said. “So, we cannot say if we would have used an angiography-based PCI, as the result would have been the same because we would have overtreated the patient. I cannot say that would have been the same with the non-angiography-derived PCI.”

In an accompanying editorial commentary published Saturday online in The New England Journal of Medicine, Shamir R. Mehta, MD, from McMaster University and Hamilton Health Sciences in Ontario, wrote that the trial “confirms the benefit of complete revascularization … and provides additional evidence for this approach in older patients.”

“The overall frequency of major cardiovascular events in the two groups in this trial was much higher than those in previous trials, which provided greater statistical power to observe moderate treatment effects at the relatively short-term follow-up of one year,” he said.

Complete revascularization beneficial to all patients?

Mehta also pointed out that the reduction in mortality with complete revascularization at 1 year was particularly notable and reinforced the finding that complete revascularization should be considered in all patients presenting with acute MI, regardless of age.

Commenting on the trial’s presentation of patients with non-ST segment elevation myocardial infarction, Mehta said the trial data suggested that older patients benefited to a similar extent from complete revascularization regardless of the presence or absence of ST-segment elevation.

“This finding suggests that the underlying mechanism of recurrent events in the two conditions is likely to be more similar than different,” he added.

Mehta concluded by saying that treatment decisions in older patients with acute MI should not be based solely on chronologic age with patients differing in cognitive status, physical ability, and severity of underlying coexisting illnesses.

“Goals of therapy such as quality of life and the ability to live independently may have greater value to some patients than extending life or preventing future ischemic events,” he said.

Study methodology

The randomized Functional Assessment in Elderly MI Patients with Multivessel Disease (FIRE) trial identified 1,445 patients in total.

These patients underwent randomization (720 to receive complete revascularization and 725 to receive culprit-only revascularization).

The median age of the patients was 80 years (interquartile range [IQR], 77 to 84); 528 patients (36.5%) were women, and 509 (35.2%) were admitted for STEMI.

Functionally significant non-culprit lesions were identified either by pressure wire or angiography.

The primary outcome was a composite of death, MI, stroke or any revascularization at 1 year, and the key secondary outcome was a composite of cardiovascular death or MI.

Safety was assessed as a composite of contrast-associated acute kidney injury, stroke, or bleeding.

Sources:

Biscaglia S, Guiducci V, Escaned J, et al.  Complete or Culprit-Only PCI in Older Patients with Myocardial Infarction. N Engl J Med. 2023 Aug 26 (Article in press).

Mehta SR. Complete Revascularization in Older Patients with Myocardial Infarction. N Engl J Med. 2023 Aug 26 (Article in press).

Image Caption: Simone Biscaglia, MD, speaks during a press conference at the European Society of Cardiology congress 2023 in Amsterdam. (Screenshot)