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

Artificial oxygen (O(2)) 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.