Temporal associations of coronary plaque burden and myocardial perfusion with clinical outcomes
J Dahdal, T Maaniitty, R Jukema, N Nurmohamed, P Raijmakers, R Driessen, M Maenpaa, S Bar, N van Royen, J Bax, A Saraste, S el Messaoudi, J Knuuti, P Knaapen, I DanadAbstract
Background
Coronary plaque burden and myocardial ischaemia are both recognised markers of risk in patients with suspected coronary artery disease (CAD). However, their relative impact on cardiovascular outcomes over time remains incompletely understood.
Purpose
To investigate the time-dependent prognostic value of quantitatively assessed coronary plaque burden and myocardial ischaemia in patients with suspected CAD.
Methods
We included patients with suspected CAD who underwent coronary computed tomography angiography (CCTA) and [15O]H2O positron emission tomography (PET) myocardial perfusion imaging. Plaque burden was measured on CCTA as percent atheroma volume (PAV) using AI-based analysis. Myocardial perfusion was assessed on PET by regional hyperaemic myocardial blood flow (hMBF). Multivariable Cox regression models including both PAV and hMBF were used to evaluate associations with a composite endpoint of death, non-fatal myocardial infarction, or unstable angina at 3, 6, and 9 years.
Results
Among 1,385 patients, mean age was 62 ± 9 years, 746 (54%) were men, median PAV was 7.9% (IQR: 2.7%–16.4%), and impaired regional perfusion was present in 678 (49.0%). During a median follow-up of 7.1 years, 185 patients (13%) experienced the composite endpoint. Higher PAV was independently associated with greater risk at all assessed time points, with HRs ranging from 1.036 to 1.047 per 1% increase (all p<0.001) (Figure 1). Lower hMBF was independently associated with adverse outcomes at 3 years (HR: 1.050; p=0.004) and 6 years (HR: 1.028; p=0.024), but not at 9 years (HR: 1.020; p=0.063), per 0.1 mL/min/g decrease (Figure 1). After excluding patients who underwent early revascularization, lower hMBF remained associated with outcomes throughout follow-up (Figure 2).
Conclusions
Coronary plaque burden and myocardial ischaemia provide independent prognostic information in suspected CAD. Plaque burden showed a consistent association with adverse outcomes over time, whereas ischaemia was mainly related to short- and intermediate-term risk, likely influenced by the effects of myocardial revascularization.Figure 1Figure 2