DOBUTAMINE ECHOCARDIOGRAPHY AND TL-201 IMAGING PREDICT FUNCTIONAL IMPROVEMENT AFTER REVASCULARIZATION IN SEVERE ISCHEMIC LEFT-VENTRICULAR DYSFUNCTION

Objectives-To evaluate the concordance between thallium-201 uptake and echocardiographic wall thickening, which are both indicators of poten tially reversible myocardial dysfunction, in patients with chronic isc haemic left ventricular failure and to assess their relative contribut ion to predicting improvement in regional function after revascularisa tion in a subgroup. Patients and methods-45 patients with chronic isch aemic left ventricular dysfunction (mean (SD) ejection fraction 25 (8) %) underwent echocardiography before and after dobutamine infusion (10 mu g/kg/min). Of these, 22 patients underwent rest echocardiography a t a mean (SD) of 9 (1) weeks after revascularisation. (201)T1 imaging was performed during dobutamine echocardiography and at rest, 1, and 4 h after treatment with sub-lingual glyceryl trinitrate on two separat e days. Potentially reversible dysfunction was thought to be present w hen a myocardial segment contained a T1 score of greater than or equal to 3 (ascending score 13), or showed improved wall thickening of a dy synergic segment during dobutamine stimulation. Results-Of the (201)T1 protocols, the redistribution scan Ih after treatment with glyceryl t rinitrate best demonstrated myocardial viability. Concordance between (201)T1 and dobutamine induced wall thickening was 82% (kappa = 0.59) for detecting potentially reversible myocardial dysfunction before rev ascularisation (n = 45). Regional function improved in 18 of 22 patien ts after revascularisation. There were 168 dysynergic segments before intervention. The sensitivity of echocardiography and (201)T1 imaging for detecting (''recoverable'') or viable segments after revascularisa tion was 87% and 92% respectively and specificity was 82% and 78% resp ectively (P = NS). Conclusions-Dobutamine echocardiography and (201)T1 imaging may be used to predict mechanical improvement in dysynergic s egments after revascularisation in patients with chronic ischaemic lef t ventricular dysfunction.