Effect of lidocaine on acute regional myocardial ischemia and reperfusion in the cat. An in-vivo 31P magnetic resonance spectroscopy study.
OBJECTIVE
The authors examined the relationship between myocardial infarction, high-energy phosphate compounds, and regional contractility after myocardial ischemia and reperfusion in cats.


METHODS
Hemodynamic measurements, high-energy phosphate levels, and segmental shortening were measured every 30 minutes in two groups of cats subjected to 2 hours of occlusion of the left anterior descending coronary artery and 4 hours reperfusion. Group 1 (n = 10) animals were infused with a low level of lidocaine, 0.05 mg/kg/hr, while group 2 (n = 10) received a higher dose, 7.5 mg/kg/hr. The infarcted region was measured postmortem.


RESULTS
Group 1 animals had larger infarcts (39 +/- 6 vs. 12 +/- 5% of jeopardy, P < .05) and less phosphocreatine recovery during reflow (52 +/- 7% vs. 73 +/- 2% of control, P < .01) than did group 2. Group 2 showed recovery of percentage systolic shortening during reflow (1.4 +/- 2% at 30 minutes vs. 7.1 +/- 2.3% at 4 hours, P < .05), whereas group 1 exhibited no improvement. A significant correlation was found between infarct size under the surface coil and phosphocreatine content during reflow, but not between contractile function and infarction size or metabolite levels during reflow.


CONCLUSIONS
Lidocaine infusion enhanced recovery of myocardial contractility during reperfusion and decreased infarct size. Greater recovery of phosphocreatine during reperfusion was predictive of greater myocardial salvage during reperfusion.
Wendland
M F
MF
Department of Radiology, University of California, San Francisco 94143.
Saeed
M
M
Kondo
C
C
Derugin
N
N
Higgins
C B
CB
D000818:Animals; D002415:Cats; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D008012:Lidocaine / Q000627:therapeutic use*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D017202:Myocardial Ischemia / Q000188:drug therapy*; D015425:Myocardial Reperfusion
D008012:Lidocaine