Presence of FFR–negative high-risk non-culprit plaque tied to worse clinical outcomes in patients with MI: JAMA

The researchers found that MACE (defined as all-cause mortality, unplanned revascularization, and nonfatal MI) occurred in 15% of patients with and 8% without a high-risk plaque after 2 years in the cohort study (PECTUS-obs) involving 420 patients with MI. After adjustment for clinical variables, the presence of a high-risk plaque was tied to a 2-fold increased MACE risk, driven primarily by higher revascularization rates.

Patients with myocardial infarction are known to have high rates of recurrent MACE (major adverse cardiovascular events) even after FFR-guided complete revascularization. These recurrences may be due to FFR-negative high-risk non-culprit lesions. Jan-Quinten Mol, Radboud University Medical Center, Nijmegen, the Netherlands, and colleagues aimed to assess the association between optical coherence tomography (OCT)-identified high-risk plaques of FFR-negative non-culprit lesions and MACE occurrence in patients with MI.

PECTUS-obs is a prospective, multicenter, international, observational cohort study. OCT was performed on all FFR-negative (FFR > 0.80) non-culprit lesions in patients presenting with MI. A high-risk plaque was defined as containing at least 2 of the following prespecified criteria: (1) a fibrous cap thickness less than 65 μm, (2) a lipid arc at least 90°, and (3) either plaque rupture or thrombus presence. Patient enrollment was done from 2018 to 2020 and data analysis from 2022 to 2023.

A comparison was drawn for MACE occurrence (primary endpoint) in patients with and without a high-risk plaque, at a 2-year follow-up. A total of 438 patients were enrolled, and OCT findings were analysed in 420. Among the included patients, the mean age was 63 years, 81.0% were men, and STEMI and non-STEMI were equally represented (51.7% and 48.3%).

The study led to the following findings:

• A mean of 1.17 non-culprit lesions per patient was imaged.
• Analysis of OCT images revealed at least 1 high-risk plaque in 143 patients (34.0%).
• The primary endpoint occurred in 15.4% of patients with a high-risk plaque and 8.3% of patients without a high-risk plaque (hazard ratio, 1.93), primarily driven by more unplanned revascularizations in patients with a high-risk plaque (9.8% versus 4.3%).

"To our knowledge, PECTUS-obs is the first prospective cohort study to reveal that the presence of a high-risk plaque is associated with a worse clinical outcome in patients with MI and FFR-negative non-culprit lesions, with a higher number of unplanned revascularization being a primary factor," the researchers wrote.

"In a population with a high recurrent events rate, despite physiology-guided complete revascularization, these results call for research on the potential benefit of additional pharmacological or focal treatment strategies in patients harbouring high-risk plaques," they concluded.

Reference:

Mol J, Volleberg RHJA, Belkacemi A, et al. Fractional Flow Reserve–Negative High-Risk Plaques and Clinical Outcomes After Myocardial Infarction. JAMA Cardiol. Published online September 13, 2023. doi:10.1001/jamacardio.2023.2910