Cardiac Force and Muscle Shortening in Regional Ischemia: Asynchronization and Possible Uncoupling

Acute myocardial ischemia affects both cardiac muscle force development and shortening in the affected regions. The exact mechanisms are unclear. We investigated myocardial function during ischemia and reperfusion both experimentally and with a muscle fiber model. The model was subjected to perturbations in contractility and force activation. Results show that the cardiac muscle model reflects many of the physiological changes observed in myocardial ischemia and reperfusion. Asynchronization between force generation and muscle shortening observed during regional ischemia and reperfusion may be dependent on the extent of their uncoupling