Cardiac

• Endocardium, myocardium, epicardium


  Three layers of the heart
• Cardiac valves


  • Atrioventricular valves: tricuspid and mitral
  • Semilunar valves: aortic and pulmonic
• Cardiac conduction system


  • Electrophysiology
• Cardiac hemodynamics


  The dynamics of blood flow and pressure within the cardiovascular system
• Repolarization


  Return of cell to resting state caused by reentry 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 cycle


  Events that occur in the heart from the beginning of one heartbeat to the next
• Stroke volume (SV)


  Amount of blood ejected with each heartbeat
• Contractility


  Ability of cardiac muscle to shorten in response to electrical impulse
• Control of heart rate

  • Autonomic nervous system, baroreceptors
• Contractility


  • Increased by catecholamines, SNS, certain medications
  • Decreased by hypoxemia, acidosis, certain medications
• Health history information


  • Demographic information
  • Family/genetic history
  • Cultural/social factors
  • Risk factors: Modifiable, Nonmodifiable
• Common cardiovascular symptoms


  • Chest pain/discomfort
  • Pain/discomfort in other areas of the upper body
  • SOB/dyspnea
  • Peripheral edema, weight gain, abdominal distention
  • Palpitations
  • Unusual fatigue, dizziness, syncope, change in LOC
• Past health, family, and social history

  • Medications
  • Nutrition
  • Elimination
  • Activity, exercise
  • Sleep, rest
  • Self-perception/self-concept
  • Roles and relationships
  • Sexuality and reproduction
  • Coping and stress tolerance
• Physical assessment of the cardiovascular system

  • General appearance
  • Skin and extremities
  • Pulse pressure
  • Blood pressure; orthostatic changes
  • Arterial pulses
  • Jugular venous pulsations
  • Heart inspection, palpation, auscultation
  • Assessment of other systems
• Laboratory tests


  • Cardiac biomarkers
  • Blood chemistry, hematology, coagulation
  • Lipid profile
  • Brain (B-type) natriuretic peptide
  • C-reactive protein
  • Homocysteine
• Cardiac stress testing


  Exercise stress test, Pharmacologic stress testing
• Diagnostic tests


  • Radionuclide imaging: Myocardial perfusion imaging, Positron emission tomography, Test of ventricular function, wall motion
  • Computed tomography
  • Magnetic resonance angiography
• Echocardiography


  Noninvasive ultrasound test used to measure ejection fraction, examine size, shape, and motion of cardiac structures, Transthoracic, Transesophageal
• Cardiac catheterization


  Invasive procedure used to diagnose structural and functional diseases of the heart and great vessels, Right heart catheterization, Left heart catheterization
• Nursing interventions


  • Observe cath site for bleeding, hematoma
  • Assess peripheral pulses
  • Evaluate temperature, color, and capillary refill of affected extremity
  • Screen for arrhythmias
  • Maintain bed rest 2 to 6 hours
  • Instruct patient to report chest pain, bleeding
  • Monitor for contrast-induced nephropathy
  • Ensure patient safety
• Arrhythmias


  Disorders of formation or conduction (or both) of electrical impulses within heart
• Arrhythmias


  • Can cause disturbances of rate
  • Rhythm
  • Both rate and rhythm
  • Potentially can alter blood flow and cause hemodynamic changes
  • Diagnosed by analysis of electrographic waveform
• Types of arrhythmias


  • Atrial: Premature atrial complex
  • Atrial flutter
  • Atrial fibrillation
  • Ventricular: Premature ventricular complex
  • Ventricular tachycardia
  • Ventricular fibrillation
  • Ventricular asystole
• Normal electrical conduction


  1. SA node (sinus node)

  2. AV node

  3. Conduction: Bundle of His

  4. Right and left bundle branches

  5. Purkinje fibers

  6. Depolarization = stimulation = systole

  7. Repolarization = relaxation = diastole
• ECG

  • Electrode placement
  • Electrode adhesion
  • Types of ECG
  • ECG interpretation: P wave
  • QRS complex
  • T wave
  • U wave
  • PR interval
  • ST segment
  • QT interval
  • TP interval
  • PP interval
• ECG rhythm analysis

  • Normal sinus rhythm
  • Sinus node arrhythmias
  • Sinus bradycardia
  • Sinus tachycardia
• Nursing intervention for ECG lead adhesion


  Clip the chest hair with the patient's permission before applying the leads
• Assessment of the patient with an arrhythmia

  • Causes of arrhythmia, contributing factors, the arrhythmia's effect on the heart's ability to pump an adequate blood volume
  • Assess indicators of cardiac output and oxygenation
  • Health history: previous occurrences of decreased cardiac output, possible causes of the arrhythmia
  • All medications (prescribed and over-the-counter)
  • Psychosocial assessment: patient's "perception" of arrhythmia
• Physical assessment of the patient with an arrhythmia

  • Skin (pale and cool)
  • Signs of fluid retention (JVD, lung auscultation)
  • Rate, rhythm of apical, peripheral pulses
  • Heart sounds
  • Blood pressure, pulse pressure
• Collaborative problems and potential complications

  • Cardiac arrest
  • Heart failure
  • Thromboembolic event, especially with atrial fibrillation
• Goals for the patient with an arrhythmia

  • Eradicating or decreasing occurrence of arrhythmia to maintain cardiac output
  • Minimizing anxiety
  • Acquiring knowledge about arrhythmia and its treatment
• Nursing interventions for the patient with an arrhythmia

  • Monitor and manage the arrhythmia
  • Reduce anxiety
  • Promote home- and community-based care
  • Educate the patient about self-care
  • Continuing care
• Nursing intervention: Monitor and manage the arrhythmia


  • Assess vital signs on an ongoing basis
  • Assess for lightheadedness, dizziness, fainting
  • If hospitalized: Obtain 12-lead ECG
  • Continuous monitoring
  • Monitor rhythm strips periodically
  • Antiarrhythmic medications
  • "6-minute walk test"
• Nursing intervention: Minimize anxiety


  • Stay with patient
  • Maintain safety and security
  • Discuss emotional response to arrhythmia
  • Help patient develop a system to identify factors that contribute to episodes of the arrhythmia
  • Maximize the patient's control
• Nursing intervention: Promote home and community-based care

  • Educate the patient: Treatment options
  • Therapeutic medication levels
  • How to take pulse before medication administration
  • How to recognize symptoms of the arrhythmia
  • Measures to decrease recurrence
  • Plan of action in case of an emergency
  • CPR (family)
• Nursing intervention: Continuing care

  • Referral for home care
  • Hemodynamically unstable with signs of decreased CO
  • Significant comorbidities
  • Socioeconomic issues
  • Limited self-management skills
  • Electronic device recently implanted
• Evaluation of the patient with an arrhythmia

  • Maintain cardiac output
  • Stable VS, no signs of arrhythmia
  • Experience reduced anxiety
  • Positive attitude, confidence in ability to act if an emergency occurs
  • Express understanding of arrhythmia and treatment
• Pacemakers


  Electronic device that provides electrical stimuli to heart muscle
• Types of pacemakers


  • Permanent
  • Temporary