Characterizing cardiac adipose tissue in post-acute myocardial infarction patients via CT imaging: a comparative cross-sectional study

Aims: To identify differences in CT-derived perivascular (PVAT) and epicardial adipose tissue (EAT) characteristics that may indicate inflammatory status differences between post-treatment acute myocardial infarction (AMI) and stable coronary artery disease (CAD) patients. // Methods and Results: A cohort of 205 post-AMI patients (age 59.8±9.2, 92.2% male) was propensity-matched with 205 stable CAD patients (age 60.5±10.0, 90.2% male). Coronary CT angiography and non-contrast CT scans were performed to assess PVAT mean attenuation across major coronary segments and EAT mean attenuation and volumes, respectively. For post-AMI patients, CT scans were conducted 28.6 ± 13.8 days after the AMI incidence. Post-AMI patients showed higher non-culprit PVAT and EAT mean attenuation than stable CAD patients (8.01HU, 95% CI 5.90 to 10.11 HU, p<0.001, 2.48 HU, 95% CI 0.83 to 4.13 HU, p=0.003, respectively). The EAT volume percentage at higher attenuation levels was higher in post-AMI patients compared to stable CAD (33.93cm3, 95% CI 16.86 to 51.00 cm3, p<0.001), with the difference maximized at the -70 HU threshold (4.75%, 95% CI 3.64% to 5.87%, p<0.001). PVAT mean attenuation positively correlated with EAT mean attenuations and the percentage of EAT volume >-70 HU (p<0.001 for both). // Conclusions: Post-AMI patients showed higher PVAT and EAT attenuation than stable CAD patients, potentially indicating AMI-associated inflammatory cardiac adipose tissue changes. -70 HU can act as a potential cut-off for inflamed EAT. These findings highlight the potential of using CT-derived adipose tissue characteristics to assess inflammation and guide post-AMI management strategies.