Myocardial viability by contrast-enhanced cardiovascular magnetic resonance in patients with coronary artery disease: comparison with gated single-photon emission tomography and FDG position emission tomography

Abstract

Background: The aim of this study was to assess the value of contrast-enhanced cardiovascular magnetic resonance (CMR) in viability for patients with coronary artery disease and left ventricular (LV) dysfunction (ejection fraction [EF] </=50%), comparing to gated thallium-201 ((201)Tl) single photon emission computed tomography (SPECT) and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET).

Methods and results: One hundred sixteen patients (EF 37.8 +/- 16.2%) underwent stress-reinjection or rest-redistribution gated-SPECT and CMR (46 FDG-PET) within 1 month. All images were analyzed in a 17-segment and 0-4 scales system. Of 1972 segments, delayed enhancement (DE) on CMR correlated well with (201)Tl reduction (r = 0.90, p < 0.0001). The agreement of SPECT (>/=50% maximal (201)Tl activity) and CMR (</=50% DE) was 96.8% (kappa = 0.62). CMR detected more subendocardial scars in 18 subjects (60 segments). Reduced (201)Tl activity but none DE were observed in 19 subjects (76 segments; more inferior) who had lower EF and larger end-systolic volume (p < 0.05). Of 411 dysfunctional segments from 46 patients, FDG-PET (>/=50% of maximal FDG uptake) detected more viability (9%).

Conclusion: The extent of DE correlated (201)Tl activity well. CMR could detect more small infarcts, while FDG-PET could detect more viability. CMR could distinguish between artifacts or infarction on SPECT, especially in poor LV function.