Revascularization of hibernating myocardium: rate of metabolic and functional recovery and occurrence of oxidative stress.

BACKGROUND: Left ventricular (LV) dysfunction due to coronary artery disease (CAD) may improve after revascularization in patients with hibernating myocardium (HM). METHODS AND RESULTS: We compared the rate of metabolic (arterial-great cardiac vein differences of lactate, glucose and pyruvate) and functional (intra-operative transesophageal and epicardial echocardiography) recovery and occurrence of oxidative stress (myocardial release of oxidized glutathione (GSSG)) early after surgical revascularization, in patients with CAD, LV dysfunction and HM (n=16) vs those with preserved LV function (n=15). By comparing the two groups, we observed that, after de-clamping, in patients with HM (a) the kinetic of lactate production was converted to extraction (P<0.01 at 1, 5, 10 and 20 min after revascularization), (b) myocardial extraction of pyruvate increased (P<0.01 during the first 5 min after revascularization), (c) GSSG release was less and of shorter duration (P<0.01 at all times), (d) segmental wall motion score improved from 2.4+/-0.3 to 1.7+/-0.5 (P<0.01) as did the thickening of the akinetic territories corresponding to the antero-distal septum and to the distal anterior wall regions (to 36+/-23\%, and to 36+/-13\%, respectively). There was a correlation between the rate of recovery of metabolic and functional indices. CONCLUSIONS: The contractile and metabolic recovery of HM is more rapid than that of non-HM, and it is not accompanied by oxidative stress.