Cardiovascular System - Part 3 Notes

Coronary Artery Disease (CAD)

• Recap: Plaque buildup in coronary arteries (atherosclerosis) restricts blood supply to the heart.
• Risk Factors:
  • Hyperlipidemia: Contributes to plaque formation.
  • Hypertension.
  • Diabetes.
• Mechanism: Plaque accumulates, arteries narrow, blood flow decreases.
• Symptoms:
  • Initially asymptomatic.
  • Chest pain (angina).
  • Palpitations.
  • Shortness of breath.
  • Fatigue.

Angina

• Definition: Chest pain due to reduced blood flow and oxygen to the heart.
• Types:
  • Stable Angina:
    • Predictable, occurs with activity.
    • Relieved by rest and nitroglycerin.
    • Nitroglycerin: Vasodilator to reduce heart demand.
  • Unstable Angina:
    • Persistent, not relieved by rest or medication.
    • Requires immediate medical attention (call 911).

Acute Coronary Syndrome (ACS)

• Plaque rupture in a coronary artery leads to blood clot formation, blocking blood flow.
• Myocardial Infarction (MI):
  • Heart tissue death due to blocked blood flow; an emergency.
• Symptoms:
  • Unstable angina.
  • Shortness of breath.
  • Diaphoresis (sweating).
  • Palpitations.
  • Fatigue.
  • Weakness.
  • Dyspnea (difficulty breathing).
  • Nausea.
  • Epigastric pain.
• Atypical Presentations:
  • More common in women, older adults, and individuals with diabetes.

Myocardial Infarction (MI) Management

• Immediate Actions:
  • Call EMS for transport to the emergency department.
  • Obtain an ECG.
• ECG Findings:
  • ST Elevation MI (STEMI): ST elevation in specific leads.
    • Inferior Wall MI: ST elevation in leads II, III, and AVF.
  • Non-ST Elevation MI (NSTEMI): ST depression or T wave inversion.
• Post-MI Management:
  • Stent placement.
  • Dual Antiplatelet Therapy (DAPT): Aspirin + P2Y12 inhibitor (e.g., Plavix, Brilinta) for typically one year.
    • Based on ischemic and bleeding risk assessment.

Dysrhythmias

• Atrial Fibrillation (AFib):
  • Rapid, disorganized atrial impulses leading to uncoordinated ventricular activity.
  • Symptoms:
    • Palpitations.
    • Fatigue.
    • Dizziness.
    • Shortness of breath.
  • ECG Findings:
    • Irregularly irregular heartbeat.
    • Absent P waves.
  • Management:
    • Stable patients: Outpatient management to find the cause.
    • Unstable patients: Emergency department referral.
    • Risk of blood clots due to atrial quivering.
    • Anticoagulation: Based on risk factors.
      • Direct Oral Anticoagulants (DOACs): Eliquis, Xarelto.
      • Vitamin K Antagonist: Warfarin (requires PT/INR monitoring).
        • Target INR: 2-3. Normal INR is around 1.
        • Antidote: Vitamin K.
• Supraventricular Tachycardia (SVT):
  • Rapid, narrow complex tachycardia originating above the ventricles.
  • Symptoms: Palpitations, shortness of breath, weakness, diaphoresis.
  • Management:
    • Call EMS for ED transfer.
    • Vagal maneuvers (e.g., Valsalva) to reduce heart rate.
• Sinus Dysrhythmia:
  • Heart rate variation with breathing (increases on inspiration, decreases on expiration).
  • Common in young, healthy athletes.
  • Typically benign and requires no treatment.

Endocarditis

• Inflammation of the inner lining of the heart.
• Types:
  • Infective (most common).
    • Typically caused by bacterial infection (Staphylococcus, Streptococcus).
  • Non-infective.
• Risk Factors (The Five D's):
  • Dental disease/procedures.
  • IV drug use.
  • Cardiac devices.
  • Pre-existing heart diseases.
  • Diseases of the Bowel.
• Signs and Symptoms:
  • Infection manifestations: Fever, fatigue, chills.
  • Cardiovascular symptoms: Chest pain, shortness of breath.
  • Janeway lesions: Flat, red macules on palms and soles.
  • Osler nodes: Painful, red nodules on fingers and toes.
  • Splinter hemorrhages: Streaks of broken blood vessels under nails.
  • Roth spots: Retinal hemorrhages with white centers.
• Management:
  • Refer to the emergency department immediately (serious, potentially fatal).