Reviewer: Dr Derya Baykiz

Name of the Study: Prediction of Recurrent Events with 18F-Fluoride to Identify Ruptured and High-risk Coronary Artery Plaques in Patients with Myocardial Infarction (PRE18 FFIR)

Published Congress: ESC 2022

Background:

Although high-risk coronary artery plaques identified by invasive imaging approaches have been associated with future coronary events, these techniques are impractical for widespread clinical use. In a previous retrospective analysis of patients with cardiovascular disease, increased coronary plaque activity called coronary microcalcification activity (CMA) was found to be associated with a greater risk of myocardial infarction (MI). CMA is a measure of coronary atherosclerotic plaque activity assessed using non-invasive 18F-sodium fluoride positron emission tomography (PET) and computed tomography coronary angiography (CTCA). Coronary artery 18F-sodium fluoride uptake is a marker of active calcification in lipid-rich necrotic atheromatous plaques.

Objective:

The objective of the present study was to investigate whether CMA could predict recurrent coronary events in patients with recent MI.

Methods:

This multicentre prospective study included patients aged 50 years or older with a recent (within 21 days) MI and multivessel coronary artery disease on invasive coronary angiography or previous coronary revascularisation between 2015 and 2020. All participants underwent 18F-sodium fluoride PET and CTCA. CMA=0 indicated low coronary atherosclerotic plaque activity and CMA>0 indicated high coronary atherosclerotic plaque activity. Overall, 704 patients were randomized to two groups: CMA>0 (n=421), and CMA=0 (n=283). The primary endpoint was cardiac death or non-fatal MI but was expanded during the study to include unscheduled coronary revascularisation due to lower than anticipated primary event rates.

Results:

The average age of patients was 64 years (85% men). Some 89% had multivessel coronary artery disease. GRACE risk scores were similar between the two groups. During a median follow up of four years, the composite primary endpoint occurred in 51 patients (18%) in the CMA=0 group and 90 patients (21%) in the CMA>0 group. Increased coronary atherosclerotic plaque activity was not associated with the primary endpoint (hazard ratio [HR] 1.25; 95% confidence interval [CI] 0.89–1.76; p=0.20). In secondary analyses, increased coronary atherosclerotic plaque activity was associated with all-cause mortality (HR 2.43; 95% CI 1.15–5.12; p=0.020) and with the original primary endpoint of cardiac death or non-fatal MI (HR 1.82; 95% CI 1.07–3.10; p=0.028).

Conclusion:

Increased coronary atherosclerotic plaque activity is not associated with all coronary events but predicts cardiac death or non-fatal MI and all-cause mortality.

Interpretations:

Coronary atherosclerotic plaque activity predicts spontaneous recurrent atherothrombotic events. CMA assessment could guide the application of more intensive lipid-lowering, anti-inflammatory or other advanced therapies to prevent recurrent spontaneous atherothrombotic events.