Plaque inflammation and noncalcified burden predict adverse events after percutaneous coronary intervention

Background Percutaneous coronary intervention (PCI) alleviates ischemic symptoms in stable coronary artery disease (CAD) but does not improve long-term cardiovascular outcomes. Recognizing lesions confer cardiovascular risk even after PCI is critical to optimize outcomes. Purpose This study aimed to assess whether coronary CT angiography (CCTA)-derived plaque parameters reflecting inflammation and component are associated with future risk after PCI Materials and Methods Patients with stable CAD who underwent CCTA followed by PCI within 30 days were included across three tertiary centers in 2021–2022. Pre-PCI fat attenuation index (FAI, a marker of local coronary inflammation) and plaque components (calcified, noncalcified, low-attenuation) were quantified from CCTA at PCI-treated lesions. The primary endpoint was the composite of major adverse cardiovascular events (MACE), including cardiovascular death, non-fatal myocardial infarction, repeat revascularization, or hospitalization for unstable angina. Periprocedural myocardial infarction (PMI) was evaluated as a potential mediator. Results Among 2,013 patients included, 226 (11.2%) experienced MACE over a median follow-up of 2.5 years. Higher FAI (adjusted HR per SD: 1.53, 95% CI: 1.34–1.74, P<0.001) and greater noncalcified burden (adjusted HR per SD: 1.19, 95% CI: 1.04–1.36, P=0.012) were independently associated with increased MACE risk after PCI. The prognostic effect of FAI was stronger in patients with hyperlipidemia (P for interaction=0.006). PMI mediated 1.7% and 4.5% of the associations of FAI and noncalcified burden with MACE, respectively. Conclusion Plaque inflammation and noncalcified burden are associated with prognosis after PCI. These findings support the potential utility of these markers in guiding future investigations of treatment strategies.