Prognostic values of perfusion-metabolic mismatch in Tl-201 and BMIPP scintigraphic imaging in patients with chronic coronary artery disease and left ventricular dysfunction undergoing revascularization.

Abstract

The aim of this study was to assess the prognostic value of the amount of perfusion-metabolic mismatch in revascularized patients with left ventricular (LV) dysfunction by means of Thallium (Tl)-201 and BMIPP imaging. Seventy-six patients with LV dysfunction and coronary artery disease underwent Tl-201 and BMIPP imaging. They were revascularized with either coronary artery bypass graft or balloon angioplasty and were entered into this study. To quantify the amount of perfusion-metabolic mismatch, SPECT images were displayed as polar maps and analyzed semiquantitatively. The patients were followed up for a mean period of 32 months for cardiac mortality and non-fatal cardiac events. Standard follow-up left ventriculography was performed 6 to 12 months after revascularization. Thirty-two patients exhibited a large amount of perfusion-metabolic mismatch (> 7 segments, group A), 28 patients had a small amount of perfusion-metabolic mismatch (2 to 6 segments, group B), and 16 patients were found to have no perfusion-metabolic mismatch (group C). Similar pre-revascularization LVEF of 35 +/- 5%, 34 +/- 8% and 36 +/- 6% increased to 45 +/- 8% (p < 0.0001), to 38 +/- 8% (p < 0.05), and to 36 +/- 3% (n.s.), respectively, after revascularization. The functional improvement after revascularization in group A was accompanied by a low rate of cardiac events during follow-up and better cardiac event free survival as judged by the Kaplan-Meier method (p < 0.05, vs. group B and C). In revascularized patients with severe LV dysfunction, the presence of a large amount of perfusionmetabolic mismatch evaluated by Tl-201 and BMIPP imaging identifies patients with the best prognosis.