Myocardial Contrast Echocardiography Versus Single Photon Emission Computed Tomography for Assessment of Hibernating Myocardium in Ischemic Cardiomyopathy: Preliminary Qualitative and Quantitative Results

Background

Single photon-emission computed tomography (SPECT) is widely used for the assessment of hibernating myocardium (HM). The aim of this study was to test the hypothesis that myocardial contrast echocardiography (MCE), because of its better spatial and temporal resolution, would be superior to SPECT for the detection of HM.

Methods

Thirty-nine consecutive patients with symptomatic ischemic cardiomyopathy underwent rest and vasodilator SPECT and MCE. Of these, 23 survived to undergo assessment 3 months after revascularization for the recovery of left ventricular (LV) function (spontaneous recovery or dobutamine induced), which is the definition of HM.

Results

Of the 214 dysfunctional segments, 156 segments demonstrated HM in the 23 patients, of whom 16 showed significant improvement in LV function. Logistic regression analysis showed that both qualitative and quantitative MCE were independent predictors for the detection of HM (P < .0001 vs P = .06 for qualitative MCE vs qualitative SPECT, respectively, and P < .01 vs P = .25 for all quantitative myocardial contrast echocardiographic parameters vs quantitative SPECT, respectively). Using clinical and LV functional data, SPECT, and MCE for predicting the recovery of LV function, MCE was the only independent predictor (P = .03).

Conclusion

MCE was superior to SPECT for the assessment of HM in ischemic cardiomyopathy.

Keywords: Myocardial contrast echocardiography, SPECT, Hibernating myocardium

Abbreviations: AUC, Area under the curves, CAD, Coronary artery disease, HM, Hibernating myocardium, LV, Left ventricular, MBF, Myocardial blood flow, MCE, Myocardial contrast echocardiography, RMBF, Resting MBF, ROC, Receiver operating characteristic, SPECT, Single photon-emission computed tomography