Cardiopulmonary Support Mitigates the Effects of Experimental Myocardial Ischemia

¹ From the Department of Surgery, University of Minnesota, Veterans Affairs Medical Center, Minneapolis
² From the Department of Sections of Medicine, Veterans Affairs Medical Center, Minneapolis

The effectiveness of cardiopulmonary support (CPS) as a rescue method following failed angioplasty is unknown. The proximal left anterior descending (LAD) was occluded for 20 min in 21 dogs. Group 1 animals (n=15) were given CPS and group 2 animals (n=6) served as controls. During coronary occlusion, animals receiving CPS had increased mean arterial pressure (71±12 vs 58±7mmHg), decreased left atrial pressure (3±3 vs 12±3 mm Hg), increased ischemic area blood flow (0.20±0.16 vs 0.02±0.04 mL/min/g) and myocardial oxygen consumption (0.014±0.008 vs 0.003±0.006 mL O₂/min/g), decreased remote area myocardial oxygen consumption (0.026±0.010 vs 0.091±0.047 mL O₂/min/g), and an improved myocardial oxygen consumption index (0.60±0.33 vs 0.02±0.03) when compared with controls (p<0.05). During reperfusion (no CPS), group 1 animals had increased cardiac index (210±95 vs 117±46 mL/min/kg), renal blood flow (110±38% vs 53±45%), ischemic area blood flow (1.13±0.40 vs 0.58±0.27), and myocardial oxygen consumption(0.066±0.015 vs 0.032±0.018) when compared with controls (p<0.05). CPS improves oxidative metabolism in selective myocardial segments during coronary occlusion, promotes recovery of the postischemic myocardium, and results in improved peripheral circulation.

Key Words: cardiopulmonary support • myocardial ischemia • percutaneous transluminal coronary angioplasty

Submitted on May 16, 1995
Accepted on September 13, 2007