Cardiovascular System Notes

Structure and Function of the Cardiovascular System

  • Heart Anatomy: 4 chambers (right atrium, right ventricle, left atrium, left ventricle) and 4 valves (tricuspid, pulmonary, mitral, aortic).
  • Valves: Tricuspid and mitral (AV valves), pulmonary and aortic (semilunar valves).
  • Layers of the Heart: Epicardium (outer), myocardium (muscle), endocardium (inner).
  • Blood Flow:
    • Arteries carry oxygenated blood away from the heart (except pulmonary arteries).
    • Veins return deoxygenated blood to the heart (except pulmonary veins).

Comprehensive Cardiovascular Assessment Techniques

  • Auscultation Areas: Aortic, pulmonic, Erb’s point, tricuspid, mitral.
  • Blood Components: RBCs (oxygen transport), WBCs (immune support), Platelets (clotting), Plasma (carries nutrients/waste).

Cardiac Risk Factors

  • Modifiable: Hypertension, hyperlipidemia, smoking, diabetes, obesity, unhealthy diet, lack of physical activity.
  • Non-modifiable: Age, genetics, family history.

Cardiovascular Assessment Findings

  • Normal vs Abnormal:
    • Skin pallor/cyanosis indicates poor blood flow.
    • Inspect chest for pulsations, heaves (abnormal movement).
  • Peripheral Assessment: Weak pulses, prolonged capillary refill.

Diagnostic Tests for Cardiovascular Dysfunction

  • ECG: Measures electrical activity, identifies arrhythmias and myocardial infarction (MI).
  • ECHO: Ultrasound for heart structure/function; may need left lateral positioning.
  • Stress Testing: Assesses cardiac response to exertion.
  • Biomarkers: Troponin (MI diagnosis), BNP (heart failure).

Electrocardiogram Key Components

  • P Wave: Atrial depolarization.
  • PR Interval: Delay at AV node.
  • QRS Complex: Ventricular depolarization.
  • ST Segment: Represents no electrical activity (contraction state).
  • T Wave: Ventricular repolarization.
  • QT Interval: Time for ventricular depolarization and repolarization.

Arrhythmia Management

  • Wide QRS: Indicates conduction abnormality.
  • Prolonged QT: Increased risk of life-threatening arrhythmias.
  • Types of Pacemakers:
    • Temporary: Short-term, external/internal leads.
    • Permanent: For chronic issues.
    • Biventricular: Cardiac resynchronization for heart failure.

Heart Failure Pathophysiology

  • Left-Sided HF: Fluid accumulation in lungs; symptoms include cough, dyspnea.
  • Right-Sided HF: Fluid back-up due to left-sided HF; symptoms include peripheral edema.
  • Systolic vs Diastolic: Systolic has reduced ejection fraction; diastolic has stiff ventricles.

Hypertension Stages**

  • Elevated BP: 120-129/less than 80.
  • Stage 1: 130-139/80-89.
  • Stage 2: ≥140/≥90.
  • Hypertensive Crisis: ≥180/≥120 requires immediate medical assistance.

Common Treatments**

  • Heart Failure Medications: Digoxin, beta-blockers, ACE inhibitors, diuretics.
  • Education: Lifestyle changes, regular follow-ups, symptom management.

Symptoms of Arrhythmias**

  • Atrial Fibrillation: Irregular pulse, requires monitoring and anticoagulation.
  • Ventricular Tachycardia: Lethal rhythm; treatment includes amiodarone.
  • Ventricular Fibrillation: Requires immediate defibrillation.

Nursing Implications for Implanted Devices

  • Patient Education: Care of incision site, activity restrictions, monitoring for complications.