Abstract 19179: Prognostic Value of Combined Coronary Computed Tomography Angiography and Positron Emission Tomography Perfusion Imaging in Patients With Suspected Coronary Artery Disease

Abstract

Objectives: Hybrid imaging using coronary computed tomography angiography (CTA) and positron emission tomography (PET) perfusion imaging accurately detects functionally significant coronary artery disease (CAD), but its optimal clinical use remains unknown. We studied the prognostic significance of strategy utilizing sequential CTA for exclusion of CAD followed by PET perfusion imaging for evaluating functional significance of any suspected obstructive lesions with a hybrid PET-CT device in symptomatic patients with suspected intermediate probability of CAD. Methods: We identified a cohort of 864 consecutive patients undergone hybrid PET-CT for the detection of suspected CAD. All patients had CTA and based on CTA findings, haemodynamic significance of any suspected stenoses was evaluated by PET perfusion imaging using H 2 15 O during adenosine-induced stress. Major adverse cardiac events (MACE) including death, myocardial infarction (MI) and unstable angina pectoris (UAP), were collected from the national healthcare statistics. Results: After exclusion of 97 patients undergone early (< 6 months) revascularization, 767 patients with age of 61 ± 10 years (41% males) were followed-up for a median time of 2.5 years. During the follow-up 6 deaths, 5 MIs and 3 UAPs occurred. In 462 patients, obstructive CAD was excluded based on CTA alone and the remaining patients with suspected stenoses (n=305, 39.8%) underwent PET perfusion imaging. In patients with normal or non-obstructive CTA annual incidence of MACE was only 0.16%, whereas in patients with suspected stenosis based on CTA it was 1.36% (p<0.05 vs. no stenosis). In patients with suspected obstructive lesion based on CTA, patients with normal PET perfusion had significantly lower event rate than patients with ischemia (0.54 vs. 2.78%, p<0.05). Conclusion: In patients with suspected obstructive CAD PET perfusion imaging after CT angiography is able to accurately identify those patients with high risk of future MACE. Sequential use of CTA and PET perfusion imaging appears powerful and safe strategy for targeting therapeutic procedures in high risk individuals.