Prognostic value of combined FFR-CT and quantitative plaque analysis in patients with new-onset stable angina: A seven-year follow-up analysis

The prognostic value of combining fractional flow reserve derived from coronary CT angiography (FFR-CT) with artificial intelligence enabled coronary plaque analysis (AI-CPA) has not yet been fully uncovered.

The purpose of this study was to investigate how the combined information derived from FFR-CT and AI-CPA, is associated with the long-term risk of cardiovascular death (CVD) and spontaneous myocardial infarction (MI) in patients with new-onset stable angina pectoris (SAP).

The study cohort consisted of consecutively enrolled patients with new-onset SAP at three Danish centres participating in the Assessing Diagnostic Value of Non-invasive FFR-CT in Coronary Care registry (ADVANCE-DK). All patients (n=841) had ≥1 coronary stenosis >30% verified on CTA with subsequent successful core laboratory FFR-CT and AI-CPA analysis. Mean follow-up time was 7.0 years (range: 6.3-8.2). An abnormal FFR-CT was defined as a lesion-specific (2cm distal-to-stenosis) value ≤0.80. AI-CPA was considered abnormal when patient level total plaque burden (total plaque volume mm^3/total vessel volume mm^3*100) was ≥ the 50%-percentile. Patients were divided into; 1) abnormal FFR-CT + abnormal AI-CPA, 2) abnormal FFR-CT + normal AI-CPA, 3) normal FFR-CT + abnormal AI-CPA and 4) normal FFR-CT + normal AI-CPA. The endpoint was a composite of CVD or non-fatal spontaneous MI. Event data were extracted from the Western Denmark Heart Registry and electronic hospital patient files. An external independent event committee adjudicated all events.

In 841 patients, FFR-CT was abnormal in 347 (41%) and AI-CPA in 419 (50%). Overall, two normal test results were present in 305 (36%) patients, normal FFR-CT + abnormal AI-QCPA in 189 (22%), abnormal FFR-CT + normal AI-QCPA in 117 (14%) and two abnormal test results in 230 (27%). Baseline characteristics for patients within each group are provided in Table 1. During the follow-up, 69 endpoints occurred of which 35/69 (51%) were spontaneous MIs. Risk of the endpoint was lowest in the category of normal FFR-CT + normal AI-CPA with a significant positive trend towards higher risk if abnormal FFR-CT + normal AI-CPA or normal FFR-CT + abnormal AI-CPA followed by the highest risk observed for abnormal FFR-CT + abnormal AI-CPA, Figure 1.

In patients with new-onset SAP the combined information derived from FFR-CT and AI-CPA stratified patients into low (double normal), intermediate (one normal one abnormal) and high (double abnormal) risk of adverse outcomes. These findings indicate that FFR-CT and plaque-assessment provides independent and additive long-term prognostic information in patients with intermediate range coronary stenosis.