A novel, noninvasive, highly sensitive technique that uses an antimatter probe to light up the inflamed – or “hot” – disease in the coronary arteries predicts the future risk of fatal heart disease or heart attacks, according to a new study. David Newby BA, BSc (Hons), BM, MD, of the University of Edinburgh, Scotland, presented these findings from the PRE18FFIR study Sunday at the European Society of Cardiology (ESC) Congress 2022 in Barcelona, Spain. The PRE18FFIR was a prospective cohort study that was conducted in nine heart centers across four countries on three continents. The study investigated whether coronary microcalcification activity (CMA) could predict recurrent coronary events in patients with recent myocardial infarction (MI). It is based on the findings that 18F-sodium fluoride is a marker of active calcification in lipid-rich atheromatous plaques and CMA is a measure of coronary atherosclerotic plaque activity and can be assessed using 18F-sodium fluoride positron emission tomography (PET) and computed tomography coronary angiography (CTCA). The study enrolled 704 patients between 2015 and 2020 with recent heart attacks and multivessel coronary artery disease. The mean age of the participants was 64 years, and 85% were men. The majority (89%) of patients had multivessel coronary artery disease, 7% had left main coronary artery disease, and 4% had single-vessel disease. All participants underwent 18F-sodium fluoride PET and CTCA scans, and an independent blinded core laboratory evaluated CMA. The CMA value of 0 indicates low coronary atherosclerotic plaque activity, and CMA>0 indicates high coronary atherosclerotic plaque activity. The two groups had similar mean Global Registry of Acute Coronary Events (GRACE) scores. The follow-up period was minimum of 2 years and an average of 4 years. The primary endpoint was cardiac death or non-fatal MI; it was expanded during the study to include unscheduled coronary revascularization due to lower-than-anticipated primary event rates. The study found 283 patients with CMA=0 (“cold” artery group) and 421 patients with CMA>0 (“hot” artery group). The higher 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). However, a secondary analysis showed an increased cumulative incidence of death from heart disease or heart attack in the hot-artery group (HR 1.82; 95% CI 1.07 to 3.10; p=0.03) compared to cold-artery group. Similarly, cumulative incidence of death from any cause was higher in the hot-artery group (HR 2.43; 95% CI 1.15 to 5.12; p=0.02) than in the cold-artery group. “These findings indicate that coronary atherosclerotic plaque activity predicts spontaneous recurrent atherothrombotic events,” Newby said in an ESC press release. “CMA assessment could guide the application of more intensive lipid-lowering, anti-inflammatory or other advanced therapies to prevent recurrent spontaneous atherothrombotic events.” During a press conference, Newby explained that the study did not predict the probability or recurrent revascularization “because I think there are different things that drive why you need to have recurrent revascularization.” The PRE18FFIR study was funded by the Wellcome Trust.