Determination of cardiac performance. (a) Tracings from continuous monitor recordings obtained during ischemia and reperfusion. Each tracing demonstrates the aortic and left ventricular transduced pressure over time. The mid-point in the tracing is at 20 min of reperfusion. The conditions are modified modified Kreb's Henseleit working solution (MK) alone, MK plus tumour necrosis factor (TNF)-α, and MK plus insulin-like growth factor (IGF)-1. (b) Determination of cardiac performance is as described in the Methods section (see text) and includes calculation of the pressure gradient between the systolic and diastolic pressure transductions from the aorta and left ventricle. As demonstrated, reperfusion with IGF-1 generates a significant improvement in cardiac performance at all time points. Analysis demonstrated a significant difference between reperfusion with IGF-1 plus MK as compared with MK alone and MK plus TNF-α (P < 0.005).