Clinical Investigations Comparison of Perfusion-Metabolism Mismatch in 99m Tc-MIBI and 123 I-BMIPP Scintigraphy With Cardiac Magnetic Resonance in Patients With Dilated Cardiomyopathy

Background: Cardiac magnetic resonance (CMR) imaging is an established method of detecting myocardial fibrosis related to prognosis in patients with dilated cardiomyopathy (DCM). Recent studies have found that 99m Tcemethoxy-isobutyl-isonitrile (MIBI) and 123 Ie15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid (BMIPP) dual single-photon-emission computerized tomography (MIBI-BMIPP dual SPECT) can detect perfusion-metabolism mismatches. We compared MIBI-BMIPP dual SPECT with CMR findings and assessed their prognostic abilities to determine the significance of abnormal metabolism in patients with DCM. Methods and Results: Fifty inpatients with DCM (age 58 6 12 y; 14 female) were assessed with the use of MIBI-BMIPP dual SPECT and CMR. Perfusion-metabolism mismatches were identified mainly at the left ventricular free wall, whereas late gadolinium enhancement (LGE) was evident mostly at the septal wall. During a median follow-up of 33 months, 9 patients developed cardiac events including death, heart failure, and fatal arrhythmia. Event-free survival rates were significantly lower for patients with LGE plus a mismatch than with other abnormalities (P 5 .001). Among clinical and imaging variables, LGE plus a mismatch was significantly associated with cardiac events (hazard ratio 7.9, 95% confidence interval 1.8e35.6; P 5 .007). Conclusions: Coexisting LGE and a perfusion-metabolism mismatch accurately predict future cardiac events in patients with DCM. (J Cardiac Fail 2013;19:445e453)