Chapter 13 - Myocardial function: from myofilaments to cardiac pump

Abstract

This chapter briefly reviews how complex left ventricular (LV) and cardiac function are from molecular and cellular function, over the spreading of electrical activation, to the development of elevated pressure, ejection and interaction with the vascular tree, dissipation of pressure and filling from pulmonary and peripheral circulation at low pressures. This complex and interrelated function achieves a remarkable efficiency and reserve capacity, at least in young and healthy subjects. With age and with disease, we observe impairment at all levels from molecular to organ function. From a clinical point of view, we deal with stiffening of heart and vessels, loss of reserve capacity, impairment of contraction and relaxation, and degeneration of cardiac valves. Last but not least, the functional and anatomical alterations of the coronary circulation will lead to ischemia and infarction. These impairments contribute to decreased functional capacity, leading to heart failure.