Chapter 21: Assessment of Cardiovascular Function

Assessment of Cardiovascular Function details the cardiac conduction system, explaining the electrophysiology of the action potential, depolarization, and repolarization, alongside the roles of the sinoatrial and atrioventricular nodes. Key hemodynamic concepts are thoroughly explored, specifically cardiac output, stroke volume, and the critical determinants of preload, afterload, and contractility, often described by the Frank-Starling law. The text outlines the nursing assessment process, emphasizing the collection of a robust health history to identify symptoms such as chest pain, dyspnea, palpitations, and fatigue, while distinguishing between gender-specific presentations of acute coronary syndrome. Physical assessment techniques are rigorously described, covering the inspection of skin for perfusion status and edema, palpation of arterial pulses and the apical impulse, and the evaluation of jugular venous distention to estimate central venous pressure. Cardiac auscultation is broken down into identifying normal heart sounds (S1 and S2) versus abnormal findings like S3 and S4 gallops, opening snaps, systolic clicks, and murmurs associated with turbulent blood flow. The chapter further categorizes diagnostic evaluations, detailing laboratory tests for cardiac biomarkers (troponin, CK-MB), lipid profiles, and brain natriuretic peptide (BNP) for heart failure management. It covers noninvasive procedures including 12-lead electrocardiography (ECG), continuous telemetry monitoring, and various forms of stress testing (exercise and pharmacologic) to detect myocardial ischemia. Advanced diagnostic imaging modalities such as echocardiography (transthoracic and transesophageal), SPECT, PET, and cardiac CT are explained regarding their utility in visualizing structural and functional abnormalities. Finally, the summary addresses invasive procedures, specifically cardiac catheterization and angiography for coronary artery evaluation, outlining essential pre-procedure and post-procedure nursing interventions to prevent complications, as well as hemodynamic monitoring using pulmonary artery catheters and arterial lines to assess intracardiac pressures in critically ill patients.