O2 cost of contractility but not of mechanical energy increases with temperature in canine left ventricle

A study was conducted on the excised, cross-circulated canine heart to examine the effects of myocardial temperature on left ventricular (LV) mechanoenergetics. The thermal effects were quantified using the framework of the LV contractility (Emax)-pressure-volume area (PVA)-myocardial oxygen consumption relationship. Emax was found to change reciprocally. Moreover, the oxygen cost of Emax proportionally changed with temperature, while that of PVA remained unchanged.