Protective effect of lidocaine during regional myocardial ischemia: an altered pathophysiologic response assessed by NADH fluorescence.
Studies were undertaken to determine the effects of lidocaine on ischemic myocardium, which was induced by coronary artery constriction in open-chested dogs. A real-time epicardial fluorescent technique to detect in vivo-reduced nicotinamide adenine dinucleotide (NADH) during 60 seconds of ischemia was used. Blood flow of ischemic myocardium was measured by using radioactive microspheres of 9 +/- 1 micrometers (mean +/- SE) and was compared with that of normal myocardium, shown by injection of alpha-zurine blue dye. Lidocaine effectively reduced peak NADH fluorescence by 18.6%, from 93.9 +/- 7.2 to 76.4 +/-4.1 mV (p less than 0.005). Lidocaine delayed the onset of fluorescence (2.2 +/- 0.2 versus 1.3 +/- 0.1 s p less than 0.002) and facilitated the recovery from ischemia (38.4 +/- 2.9 versus 54.8 +/- 2.9 s p less than 0.001). Increase in NADH concentration during ischemia correlated (r=0.76, p less than 0.006) with ischemic fluorescence. These findings were independent of altered hemodynamics or change in myocardial blood flow. Results indicate that lidocaine provides myocardial cellular protection during transient ischemia; there is an altered NADH fluorescent response to coronary artery occlusion.
D000818:Animals; D001399:Azure Stains; D002250:Carbon Radioisotopes; D003250:Constriction; D003327:Coronary Disease / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology*; D003331:Coronary Vessels / Q000503:physiopathology; D004285:Dogs; D005453:Fluorescence; D006439:Hemodynamics / Q000187:drug effects; D008012:Lidocaine / Q000494:pharmacology*; D008863:Microspheres; D009243:NAD / Q000378:metabolism*
D001399:Azure Stains; D002250:Carbon Radioisotopes; D009243:NAD; D008012:Lidocaine