Sensitivity, specificity, and predictive accuracies of non-invasive tests, singly and in combination, for diagnosis of hibernating myocardium.

Abstract

To determine the best test(s) for predicting functional recovery of hibernating myocardium after reperfusion. A prospective study to compare echocardiographic left ventricular diastolic wall thickness (> or =5 mm), low-dose dobutamine echocardiography and rest-redistribution thallium-201 scintigraphy, alone and in combination, for predicting recovery of left ventricular akinesis after surgical revascularization. Twenty-eight consecutive patients aged 58+/-9 years were studied. Of the 448 left ventricular segments, 263 were akinetic at rest; 230/263 (87%) had wall thickness > or =5 mm, 135 (51%) had a positive response and 175 (66.5%) were graded viable on thallium. Of akinetic segments 61% improved after surgery. Left ventricular score decreased from 2.3+/-0.4 to 1.8+/-0.4 (P<0.01) and ejection fraction increased from 27+/-10 to 37+/-14% (P<0.01). For predicting results at 1 year, diastolic wall thickness had a sensitivity and a predictive accuracy of a negative test of 100% but a specificity of 28% and predictive accuracy of a positive test of 61%. The addition of dobutamine echocardiography or thallium-201 improved the predictive accuracy of a positive test to 76% and 69%, respectively; the addition of both tests was not of greater benefit than that of a single test. Diastolic wall thickness <5 mm on echocardiography was the best simple and single predictor of non-recovery of left ventricular dysfunction. The addition of dobutamine echocardiography or thallium-201, but not both, was the best solution for predicting recovery of left ventricular dysfunction. In times of limited resources, these findings are important from a clinical point of view.