Treatment decisions based on hybrid myocardial perfusion SPECT and CT coronary angiography

243 Objectives Hybrid myocardial perfusion SPECT (SPECT) and CT coronary angiography (CTA) has high diagnostic performance in diagnosing coronary artery disease (CAD). We hypothesize that treatment decisions can be made in patients with stable angina pectoris based on hybrid SPECT and CTA. Methods 107 patients with stable angina pectoris and median pre-test likelihood of CAD of 87% (range 22-95) according to Diamond and Forrester criteria were included. Hybrid SPECT and CTA was performed prior to invasive coronary angiography (CA) in all patients. A panel of two cardiologists and one cardio-thoracic surgeon made treatment decisions based on; 1. Hybrid SPECT and CTA and 2. SPECT and CA. Decisions were made according to 4 categories; 1. No therapy, 2. Optimal medical treatment (OMT), 3. PCI and 4. CABG. Percent agreement between treatment decisions based on SPECT and CA versus hybrid SPECT and CTA were calculated from 3 groups. The groups were defined according to the findings by hybrid SPECT and CTA; 1. matched stenosis on CTA and corresponding ischemic myocardium on SPECT, 2. unmatched SPECT and CTA findings and 3. normal SPECT and CTA findings. Results Percent agreement (PA) between the two decisions to revascularize (None and OMT versus PCI and CABG) in all patients was 91.6%. PA in matched, unmatched and normal groups were 95%, 84% and 100% respectively. PA for method of revascularization was 72% in matched and 79% in unmatched groups. Conclusions Hybrid SPECT and CTA can play a major role in clinical decision making, even patients with high pre-test likelihood of CAD could be safely indicated for and deferred from revascularization. In selected cases PCI, and possibly CABG could be indicated based on these images