Clinical Investigations Functional Recovery After Revascularization in Patients with Coronary Artery Disease and Left Ventricular Dysfunction

The present study sought to evaluate the value of gated SPECT imaging, which provides the opportunity to acquire function and perfusion information simultaneously, under infusion of low dose dobutamine in the prediction of functional recovery after revascularization in patients with coronary artery disease and left ventricular dysfunction. Sixteen patients with stable coronary artery disease and segmental ventricular dysfunction scheduled for PTCA underwent resting echocardiogram, rest gated SPECT and gated SPECT under infusion of 5-10 ~Jg/kg/min dobutamine d uring acqu is ition on the same day, and rest/stress Tc-99m sestamibi standard perfusion iınag in g on a separate day before PTCA. The improvement of dyssynergic segments was determined with a rest echocardiogram 2 ınonth s after PTCA. A I 6-segment model was used for interpretation of the echocardiograms and the SPECT images. Wall motion was scored on a 4-point scale (O=absent, 3=normal) on gated images and perfusion was scored on a 5-point scale (O=normal, 4=absent) on gated and standard perfus ion images. On gated images, diagnostic criteria for viable dysfunctional segments were: a) wall motion score ~2. b) perfusion score ;S;2, c) a w all mot.jon score change > 1 grade with dobutamine. On perfu sion images, diagnostic criteria were taken as: a) reversible defect, b) fixed defect having >50% uptake of maximal activity. 104 segmeııts demonstrated abnormal wall motion and 72 of them improved after revascu larization. Dobutamine gated SPECT had a 86% sens itivity, 72% specificity and 82% diagnostic accuracy for predicting functional iınprovement. These values were 68%, 75% and 70%, respectively, for rest gated SPECT and 7 I%, 53% and 65%, for standard SPECT imaging. Gated imaging improved specifi city and dobutamine perfusion improved sensitivity. Thus, dobutaınin e gated SPECT has a higher diagnostic accuracy and this method may have increme ntal value in the prediction of functional iınproveınent after revascularization in patients with coronary artery disease and left ventricular dysfunction.