PEGylated carboxyhemoglobin bovine (SANGUINATE) ameliorates myocardial infarction in a rat model

Artificial oxygen (O₂ ) carriers were reported to be protective in ischemia/reperfusion (I/R) in various organs including the heart. In the current study, 20 rats underwent ligation (MI) of the left anterior descending artery, were treated with 10 mL/kg of PEGylated carboxyhemoglobin bovine (SANGUINATE, S+, n = 10) or saline (S-, n = 10) 10 minutes after MI and daily thereafter for 3 days, and were followed by weekly echocardiography for 4 weeks, when they had left ventricular pressure volume relationship (PVR) analyses followed by necropsy. Echocardiography showed an increase in end-systolic dimension rather than end-diastolic dimension, preserved fractional shortening (36 vs. 26%, P < .01), and milder mitral regurgitation in S+ compared with S- rats. PVR revealed a milder increase in end-systolic volume, larger stroke volume (101 vs. 74 μL, P < .005) and cardiac output (33.4 vs. 23.8 mL/min, P = .004) in S+ rats in actual determination and under a wide range of standardized loading conditions 4 weeks after MI. Excised heart showed significantly limited area of MI (8.9 vs. 13.3%, P = .028). The results suggest that SANGUINATE in short-term repeated doses may accelerate weight recovery, preserving the myocardium, mitral competence, and cardiac function after MI. The mechanism of action and optimal treatment for MI remain to be studied.