Chapter 26 Assessment of Cardiovascular Function Self-Review Slides

Overview of Anatomy and Physiology - Heart Three layers Endocardium Myocardium Epicardium Four chambers Heart valves Coronary arteries Cardiac conduction system Cardiac hemodynamics

Structure of the Heart

Cardiac Conduction System

Terms - Cardiac Action Potential Depolarization: electrical activation of cell caused by influx of sodium into cell while potassium exits Repolarization: return of cell to resting state caused by re-entry of potassium into cell while sodium exits Refractory periods Effective refractory period: phase in which cells are incapable of depolarizing Relative refractory period: phase in which cells require stronger-than-normal stimulus to depolarize

Cardiac Action Potential

Great Vessel and Heart Chamber Pressures

Terms - Cardiac Output Stroke volume: amount of blood ejected with each heartbeat Cardiac output: amount of blood pumped by ventricle in liters per minute Preload: degree of stretch of cardiac muscle fibers at end of diastole Contractility: ability of cardiac muscle to shorten in response to electrical impulse After load: resistance to ejection of blood from ventricle Ejection fraction: percent of end diastolic volume ejected with each heart beat

CO = SV x HR Control of heart rate Autonomic nervous system, baroreceptors Control of stroke volume Preload: Frank-Starling Law After load: affected by systemic vascular resistance, pulmonary vascular resistance Contractility increased by catecholamines, SNS, some medications Decreased by hypoxemia, acidosis, some medications

Diagnostic Tests Laboratory Tests Cardiac Biomarker Analysis CK, CK-MB Myoglobin Troponin T and I Lipid profile Brain Naturetic Peptide C-Reactive Protein Homocysteine

Diagnostic Tests Chest X-ray & Fluoroscopy Electrocardiography Continuous Electrocardiographic Monitoring Hardwire Cardiac Monitoring Telemetry Lead Systems Ambulatory Electrocardiography Transtelephonic Monitoring Wireless Mobile Cardiac Monitoring Systems

Diagnostic Tests Cardiac Stress testing Exercise Stress Testing Pharmacologic Stress Testing

Chapter 26 Assessment of Cardiovascular Function New Content

Diagnostic Tests Echocardiography Radionuclide Imaging Cardiac Catheterization Electrophysiologic Testing Hemodynamic Monitoring

Diagnostic Tests Echocardiography Traditional Echocardiography Non-invasive ultrasound which measures EF%, size, shape & cardiac structure motion Useful for diagnosis of pericardial effusions, heart murmurs, valvular function & ventricular heart motion May be performed with exercise or pharm stress test. Images obtained at rest. What findings are considered to be positive & may suggest CAD? What diagnostic tool will likely be used next if positive?

Diagnostic Tests Radionuclide imaging- involves the use of radioisotopes to evaluate coronary artery perfusion. Myocardial perfusion imaging Test of ventricular function, wall motion Computed tomography Positron emission tomography Magnetic resonance angiography

Cardiac Catherization** Invasive procedure study used to measure cardiac chamber pressures, assess patency of coronary arteries Requires ECG, hemodynamic monitoring; emergency equipment must be available Assessment prior to test; allergies, blood work Assessment of patient postprocedure; circulation, potential for bleeding, potential for dysrhythmias Activity restrictions Patient education pre-, postprocedure

Cardiac Catherization Angiography Aortography Coronary Arteriography Right Heart Catheterization Left Heart Catheterization

Cardiac Catherization Nursing Interventions Pre-procedure Fasting 8-12 hours prior to procedure (Why?) Pt informed of procedure, sesations to expect and medications given. Informed consent? Nursing Interventions Post-procedure Catheter access site is observed for bleeding or hematoma formation Pulses assessed. How often for how long? Pt. position?

Cardiac Catherization Nursing Interventions Post-procedure Complications Bleeding/hematoma at insertion site Pulses distal to insertion site Capillary refill Dysrhythmias Positioning/Client Activity? Nephropathy Pt. instructions when ambulating post-clearance. Chest pain?

Hemodynamic Monitoring Central Venous Pressure (CVP) Pulmonary artery (PA) pressure Intra-arterial BP monitoring (IABP)

Phlebostatic Level

Pulmonary Artery Catheter Refer to fig. 26-11

Pulmonary Artery Catheter and Pressure Monitoring System