Chapter 26: Alterations of Cardiovascular Function

Alterations of Cardiovascular Function chronic vascular changes create a substrate for acute thrombotic events when plaques rupture, causing myocardial infarction, stroke, and peripheral tissue ischemia. Hypertension, a major independent risk factor and consequence of atherosclerosis, produces sustained elevation of systemic pressure that damages target organs through mechanical stress and ischemic mechanisms. The chapter then explores coronary artery disease and its clinical manifestations, distinguishing reversible ischemia that produces anginal symptoms from irreversible myocyte necrosis occurring during prolonged infarction. Myocardial infarction triggers release of cardiac biomarkers and initiates inflammatory healing responses that can precipitate dangerous complications including mechanical rupture, cardiogenic shock, and life-threatening dysrhythmias. The pathophysiology of heart failure integrates multiple mechanisms—impaired contractility, diastolic stiffness, volume overload, neurohormonal compensation—and distinguishes left-sided dysfunction producing pulmonary congestion from right-sided failure causing systemic venous engorgement and peripheral edema. Valvular dysfunction disrupts normal blood flow through stenotic narrowing or regurgitant leakage, creating hemodynamic burden on adjacent cardiac chambers and driving compensatory remodeling. The chapter addresses structural aortic pathology including aneurysmal dilation and acute dissection, both representing life-threatening emergencies. Peripheral and venous disorders including arterial insufficiency, varicose veins, and thromboembolism reflect either primary vascular incompetence or secondary consequences of impaired flow and stasis. Finally, dysrhythmias emerge from abnormal automaticity or conduction disturbances triggered by ischemia, electrolyte derangement, or structural disease, potentially causing hemodynamic compromise and sudden cardiac death. Together these topics provide an integrated pathophysiological framework for understanding how cardiovascular dysfunction manifests clinically and damages organ systems.