BIOC33H3 Lecture Notes - T Cell, Pulmonary Vein, Perfusion
Document Summary
Heart failure (hf) is an abnormal clinical condition involving impaired cardiac pumping that results in the characteristic pathophysiologic changes of vasoconstriction and fluid retention. Hf is characterized by ventricular dysfunction, reduced exercise tolerance, diminished quality of life, and shortened life expectancy. Risk factors include coronary artery disease (cad) and advancing age. Hypertension, diabetes, cigarette smoking, obesity, and high serum cholesterol also contribute to the development of hf. Decreased filling of the ventricles will result in decreased stroke volume and cardiac output (co). Hf can have an abrupt onset or it can be an insidious process resulting from slow, progressive changes. Compensatory mechanisms are activated to maintain adequate co. To maintain balance in hf, several counter regulatory processes are activated, including the production of hormones from the heart muscle to promote vasodilation. Cardiac compensation occurs when compensatory mechanisms succeed in maintaining an adequate co that is needed for tissue perfusion. Cardiac decompensation occurs when these mechanisms can no longer maintain adequate.