The predictive value of 99mTc-MIBI SPECT/18F-FDG PET myocardial perfusion/metabolic imaging in patients with unrevascularized coronary chronic total occlusion and left ventricular dysfunction.

To explore the predictive value of hibernating myocardium detected by single photon emission computed tomography (SEPCT)/positron emission tomography (PET) myocardial perfusion/metabolic imaging for the adverse cardiovascular events in unrevascularized chronic coronary total occlusion (CTO) patients with left ventricular (LV) dysfunction. Additionally, we explore whether hibernating myocardium in the CTO territory can independently predictive outcomes. Patients with at least one unrevascularized CTO on coronary angiography and LV dysfunction and who underwent rest 99mTc-MIBI SPECT myocardial perfusion imaging as well as 18F-FDG PET myocardial metabolic imaging were enrolled. All patients were followed up through telephone interviews and review of medical records. The extent of total hibernating myocardium, the extents of hibernating myocardium in the CTO and non-CTO territories, the extent of total scarred myocardium, and the extents of scarred myocardium in the CTO and non-CTO territories were calculated according to the segmental perfusion/metabolism score and the segmental assignment of coronary dominance and the results of coronary angiography. The Cox proportional hazards regression models were employed to analyze the relationship between the extent of hibernating or scarred myocardium and adverse cardiovascular events. Seventy eight patients were included in the final analysis. The median follow-up duration was 70.2 (27.7, 80.3) months. The extent of total hibernating myocardium and the extent of hibernating myocardium in the CTO territory were both independent predictors for cardiac death [hazards ratio (HR) = 1.289, 95% confidence interval (CI) 1.083-1.533, P = 0.004; HR = 1.262, 95% CI 1.022-1.557, P = 0.030] and the composite endpoint events (HR = 1.190, 95% CI 1.032-1.372, P = 0.016; HR = 1.273, 95% CI 1.025-1.581, P = 0.029). The extent of hibernating myocardium in the non-CTO territory, the extent of total scarred myocardium, the extents of scarred myocardium in the CTO and non-CTO territories were all not associated with the outcome. 99mTc-MIBI /18F-FDG SPECT/PET myocardial perfusion/metabolic imaging has an important predictive value for prognosis in unrevascularized CTO patients with LV dysfunction. The extent of total hibernating myocardium, especially hibernating myocardium in the CTO territory, was an independent predictor for adverse cardiovascular events.