Added value of 3D cardiac SPECT/CTA fusion imaging in patients with reversible perfusion defect on myocardial perfusion SPECT

Objectives Integration of the functional information of myocardial perfusion SPECT(MPS) and the morpho-anatomical information of coronary CT angiography(CTA) may provide useful additional diagnostic information of the spatial relationship between perfusion defects and coronary stenosis. The aim of this study was to perform a comparison between three dimensional cardiac SPECT/CTA fusion imaging(CSCF) and MPS in patients with a reversible perfusion defect on MPS.

Methods Forty-nine patients (mean age, 65.3±10.3 y-o, 20 women) with a reversible perfusion defect on MPS (2-day adenosine stress/rest SPECT with 99mTc-sestamibi or tetrofosmin) and CTA were included. CSCF were molded(cardiac IQ fusion, GE healthcare) and compared with MPS. Quantitative coronary angiography served as a reference standard for CSCF and MPS.

Results Total 147 coronary arteries in 49 patients were analyzed. CSCF yielded the sensitivity and specificity for the detection of hemodynamically significant stenosis per coronary artery, 82.5% and 80.3%, respectively. Respective values for MPS were 68.8% and 65.6%. CSCF confirmed hemodynamic significance in 69 lesions, added 12 lesions including 2 left main disease, excluded 7 equivocal defects, corrected 4 corresponding arteries to their allocated defects and localized 4 culprit segment.

Conclusions This integration of functional and morphological information were feasible to intuitively convincing and might facilitate a comprehensive non-invasive assessment of coronary artery disease.