Introduction

Welcome to our CCRN study app! All the content in the app is created by our team of licensed CCRN nurses. All the study links (you’re on the first one for the cardiovascular system) and the practice questions are based on Barron’s CCRN book.

We hope you enjoy using our app, and that you pass your CCRN exam with flying colors.

Cardiovascular

Key Concepts to Remember

  • Diastole: The phase of the cardiac cycle when the heart relaxes and fills with blood (ventricles are filled).
  • Systole: The phase when the heart contracts and pumps blood out of the ventricles.
  • Pulse Pressure: The difference between systolic and diastolic blood pressure (normal range is 40-60 mmHg).
  • Ankle-Brachial Index (ABI): Normal value is greater than 1.

Swan-Ganz Catheter

  • Elevated PAD can suggest cardiac tamponade or mitral and left ventricular diseases.
  • This catheter provides measurements for the right atrium, right ventricle, pulmonary artery (PA), and left atrium filling pressure.
  • Pulmonary Artery Systolic Pressure (PAS): Typically ranges from 20–30 mmHg.
  • Elevated PAS can indicate pulmonary hypertension, pulmonary embolism, ARDS, or COPD.
  • Pulmonary Artery Diastolic Pressure (PAD): Normally ranges from 6–12 mmHg.

Cardiac Sounds

  • S1 (“lub”): Produced by the closure of the mitral and tricuspid valves, signaling the conclusion of diastole.
  • S2 (“dub”): Results from the closure of the aortic and pulmonary valves, indicating the end of systole.
  • S3: Often described as “KENTUCKY,” it is commonly associated with heart failure.
  • S4: Resembles the rhythm of “TENNESSEE” and is linked to myocardial infarction (MI), hypertension (HTN), aortic stenosis, or ventricular hypertrophy.

Key Locations

  • S1, S3, S4: Best auscultated at the apex of the heart.
  • S2: Heard most distinctly at the heart’s base.

EKG Normal Ranges

  • PR Interval: 0.12–0.20 seconds.
  • QRS Complex: 0.08–0.12 seconds.
  • QT Interval: 0.34–0.43 seconds.

QT Prolongation

  • A QT interval exceeding 0.43 seconds may lead to Torsades de Pointes.
  • Electrolyte Causes: Hypokalemia, hypocalcemia, and hypomagnesemia.
  • Drug Causes: Amiodarone, haloperidol, and quinidine.
  • Treatment: Administer magnesium.

Valves

  • Stenosis: A narrowing of the valve occurring during its open phase; typically chronic.
  • Insufficiency: Also referred to as regurgitation, this occurs when the valve fails to close properly.
  • Mitral Stenosis: Often linked with atrial fibrillation (A-fib) due to atrial enlargement.

Murmurs

During Systole (S1–M–S2):

  • Aortic/Pulmonary Valves Open → Stenosis.
  • Mitral/Tricuspid Valves Closed → Insufficiency.

During Diastole (S1–S2–M):

  • Mitral/Tricuspid Valves Open → Stenosis.
  • Mitral/Tricuspid Valves Closed → Insufficiency.

Valve Replacement

  • Mechanical Valves:
    • Durable and long-lasting.
    • Elevated risk of blood clots.
    • Requires anticoagulation therapy (e.g., aspirin or Plavix).
  • Surgical Considerations:
    • Avoid significant reductions in preload.
    • Conduction disturbances may arise due to proximity to the SA/AV nodes.
    • Temporary or permanent pacemaker placement may be necessary.

Hypertensive Emergency (BP >180/110)

  • Definition: Systolic BP >180 mmHg and/or diastolic BP >110 mmHg, accompanied by evidence of organ damage.
  • Categories:
    • Accelerated Hypertension: Diastolic BP >120 mmHg.
    • Malignant Hypertension: Diastolic BP >140 mmHg.
  • Management: Immediate ICU admission for rapid blood pressure reduction to lower stroke risk.
  • Medications:
    • Nitroprusside drip: Vasodilator that decreases both preload and afterload.
    • Labetalol IV push: Beta-blocker for BP control.
  • NSTEMI (Non-ST-Elevation Myocardial Infarction):
    • Partial coronary artery blockage.
    • Positive troponin levels.
    • ST-segment depression on EKG.
    • Persistent chest pain (CP).
  • STEMI (ST-Elevation Myocardial Infarction):
    • Complete coronary artery occlusion.
    • Positive troponin levels.
    • ST-segment elevation on EKG.
    • Unrelenting CP; considered life-threatening.
  • Prinzmetal’s Angina (Variant Angina):
    • Troponin levels remain normal.
    • ST-segment returns to baseline after CP is relieved by nitroglycerin.

Chest Pain (CP) Management

  • Initial Steps:
    • Perform an EKG within 10 minutes of presentation.
    • Administer 325 mg chewable aspirin immediately.
  • Therapies:
    • Anticoagulant Therapy: Prevents clot formation.
    • Antiplatelet Therapy: Includes clopidogrel (Plavix).
    • Beta-Blockers: Use metoprolol, except when CP is associated with cocaine or phosphodiesterase inhibitors (e.g., Viagra).
    • Pain Relief: Morphine or nitroglycerin.
  • PCI Consideration: If CP persists for less than 12 hours, prepare for percutaneous coronary intervention (PCI).

Key Timelines

  • Door-to-Balloon Time: PCI within 90 minutes.
  • Door-to-Fibrinolytic Therapy: Fibrinolysis within 30 minutes.

Percutaneous Coronary Intervention (PCI)

  • Signs of Reperfusion:
    • Relief of chest pain (CP).
    • Resolution of ST-segment abnormalities.
    • Occurrence of reperfusion arrhythmias, such as ventricular fibrillation (VF) or ventricular tachycardia (VT).
    • Persistent elevation of troponin and CK-MB levels due to myocardial injury.
  • Potential Complications:
    • Re-occlusion: Indicated by recurring CP and ST elevation.
    • Retroperitoneal Bleeding: Presents as back pain and low blood pressure.
    • Vasovagal Response: Can occur during sheath removal.

Acute Peripheral Vascular Insufficiency

  • Assessment: Monitor for the “5 Ps” – pain, pallor, paralysis, pulselessness, and paresthesia.
  • Management:
    • Position the bed in reverse Trendelenburg to enhance blood flow.
    • Avoid elevating the affected limb.
  • Diagnostics and Treatment:
    • Confirm diagnosis with Doppler ultrasound and arteriography.
    • Administer thrombolytics, heparin, tPA, anticoagulants, and antiplatelet medications.

Heart Failure (HF)

  • Pathophysiology:
    • Increased intracardiac pressures lead to reduced cardiac output (CO).
    • Associated with elevated left ventricular end-diastolic pressure (LVEDP).

New York Heart Association (NYHA) HF Classification

  1. Class I: No symptoms during regular activity; symptoms appear only with strenuous exertion.
  2. Class II: Mild symptoms triggered by everyday activities.
  3. Class III: Comfortable while resting but significantly limited by symptoms with minimal exertion (e.g., walking to the bathroom).
  4. Class IV: Severe symptoms present even at rest, with extreme activity limitations.

Systolic Heart Failure (SHF)

  • Issue: Ejection dysfunction with ejection fraction (EF) <40%.
  • Characteristics:
    • Imaging may show a dilated heart or a normal-sized heart.
    • Ventricular dilation often leads to valvular insufficiency.
    • S3 heart sound is notable.
  • Symptoms: Pulmonary edema, shortness of breath (SOB), hypotension, and an S3 sound.
  • Treatment: ACE inhibitors/ARBs, beta blockers, positive inotropes, and diuretics to reduce sodium and water retention.
  • Contraindications: Calcium channel blockers and negative inotropes.

Diastolic Heart Failure (DHF)

  • Issue: Impaired ventricular filling with EF >50%.
  • Characteristics:
    • Imaging reveals a normal-sized heart.
    • Ventricular walls appear thickened and hypertrophied.
    • S4 heart sound often heard in cases of hypertension.
  • Symptoms: Fatigue, dyspnea, chest pain, palpitations, S4 sound, and fainting (syncope).
  • Treatment: ACE inhibitors/ARBs, beta blockers, calcium channel blockers, and low-dose diuretics.
  • Contraindications: Positive inotropes.

Right-Sided Heart Failure (Body Fluid Congestion)

  • Contributing Factors: Pulmonary embolism, acute right ventricular (RV) infarction, pulmonary valve stenosis or regurgitation, COPD, pulmonary hypertension, and left ventricular (LV) failure.
  • Symptoms: Abdominal discomfort, dependent edema, liver enlargement (hepatomegaly), spleen enlargement (splenomegaly), tricuspid valve regurgitation, and elevated central venous pressure (CVP).

Left-Sided Heart Failure (pulmonary congestion)

Underlying causes: fluid retention, prolonged hypertension, cardiac tamponade, myocardial damage (cardiomyopathy or MI), coronary artery disease, and narrowing or dysfunction of the aortic or mitral valves.
Symptoms: difficulty breathing when lying flat (orthopnea), shortness of breath (dyspnea), low oxygen levels (hypoxemia), lung crackles, frothy pink-tinged sputum, excessive sweating (diaphoresis), heightened anxiety, and elevated pulmonary artery pressure (PAP) or pulmonary artery occlusion pressure (PAOP).

Cardiomyopathy (dilated vs. hypertrophic):

  • Systolic dysfunction: an issue with blood ejection caused by left ventricular (LV) thinning, dilation, and enlargement. Mitral valve (MV) insufficiency can result from ventricular stretching.
    Signs and symptoms: resemble those of systolic heart failure (SHF).
    Management: may involve a ventricular assist device (VAD) or heart transplant.

Hypertrophic Dysfunction (impaired filling):

  • Characterized by excessive thickening of the heart muscle, particularly the left ventricle (LV) and septum.
  • Symptoms: closely resemble those seen in diastolic heart failure (DHF).
  • Notable risk: significantly increased likelihood of sudden cardiac arrest.

Pacemaker Basics (Paced – Sensed – Response)

  • Chamber Designation:
    1. Paced chamber: Atrial (A), Ventricular (V), or Dual (D).
    2. Sensed chamber: Atrial (A), Ventricular (V), or Dual (D).
    3. Response type: Inhibited (I), Dual (D), or None (O).
  • Malfunctions:
    • Failure to Pace: No pacemaker spike appears when one is expected.
    • Failure to Capture: Pacer spike is seen, but no QRS complex follows.
    • Failure to Sense: The device paces inappropriately, ignoring native heartbeats.

Cardiogenic Shock

  • Overview:
    • The most severe form of heart failure, where compensatory mechanisms fail to sustain cardiac output (CO).
    • Key indicators:
      • Decreased stroke volume (SV) and CO.
      • Increased pulmonary artery occlusion pressure (PAOP) and systemic vascular resistance (SVR).
      • Narrow pulse pressure.
  • Treatment Goals:
    • Increase heart effectiveness: Administer positive inotropes such as norepinephrine, dopamine, dobutamine, or milrinone.
    • Reduce cardiac workload: Use vasodilators in combination with positive inotropes, intra-aortic balloon pump (IABP), or ventricular assist device (VAD) to decrease preload, afterload, and overall demand.
    • Provide supplemental oxygen or mechanical ventilation as needed.

Early (Compensatory) Stage of Cardiogenic Shock

  • Signs and Symptoms:
    • Increased heart rate (tachycardia) and respiratory rate (tachypnea).
    • Crackles and mild hypoxia.
    • Anxiety or irritability.
    • Distended neck veins.
    • Cool skin and reduced urine output (UOP).
    • Narrow pulse pressure (<40 mmHg).
    • Blood pressure (BP) may remain stable but lower than baseline.
    • Arterial blood gases (ABGs): Respiratory alkalosis or early respiratory acidosis signaling progression.

Late (Progressive) Stage of Cardiogenic Shock

  • Signs and Symptoms:
    • Severe hypotension.
    • Worsening tachycardia and tachypnea.
    • Increased crackles and hypoxemia.
    • Anxiety progressing to lethargy.
    • Clammy, mottled skin.
    • Marked decrease in urine output.

Intra-Aortic Balloon Pump (IABP)

  • Purpose:
    • Used for managing cardiogenic shock, post-bypass surgery, myocardial infarction (MI), or cardiomyopathy.
    • Provides short-term circulatory support.
  • Function:
    • Deflates during systole to reduce left ventricular afterload.
    • Inflates during diastole to enhance myocardial oxygenation.

Ventricular Assist Device (VAD)

Purpose:

  • Supports patients with left ventricular heart failure (LVHF), cardiogenic shock, or cardiomyopathy.
  • Often serves as a bridge to heart transplantation.

12-Lead EKG Interpretation

Coronary Artery Bypass Graft (CABG)

  • Intraoperative Details:
    • Large doses of heparin administered.
    • Patient kept hypothermic during the procedure.
  • Postoperative Care:
    • Monitor for complications such as bleeding, cardiac tamponade, and pericarditis.
    • Avoid clamping or milking chest tubes; ensure proper dependent drainage without loops.
    • Observe chest tube output and notify provider if drainage exceeds 100mL/hour for two consecutive hours.

Cardiac Tamponade

  • Description:
    • Heart compression caused by fluid accumulation in the pericardial sac.
  • Symptoms:
    • Jugular venous distension (JVD).
    • Muffled heart sounds.
    • Narrowed pulse pressure (<40 mmHg).
    • Pulsus paradoxus (significant drop in systolic blood pressure during inspiration).
    • Enlarged cardiac silhouette on imaging.

Pericarditis

  • Overview:
    • Inflammation of the pericardial lining.
  • Key Signs:
    • Diffuse ST elevation across all leads.
    • Chest pain worsened by deep inspiration (associated with a pericardial friction rub).
  • Management:
    • Administer pain relievers, anti-inflammatory medications, or antibiotics as appropriate.

Cardiac Trauma/Myocardial Contusion

  • Cause:
    • Blood vessel damage leading to intramyocardial bleeding.
  • Critical Points:
    • The aortic valve is most prone to rupture.
    • Papillary muscle rupture requires immediate surgical intervention.
    • ST elevation limited to the injured area.
    • Pain increases with inspiration.
    • Worse prognosis than pericarditis; death may occur within 48 hours.
  • Monitoring and Treatment:
    • Watch for arrhythmias.
    • Administer pain relief as needed.

Aneurysms

  • Common Types:
    • Aortic (75%) and thoracic (25%).
  • Indications for Surgery:
    • Diameter greater than 6 cm.
    • Maintain strict blood pressure and heart rate control (e.g., labetalol infusion).
  • Symptoms:
    • Sudden, sharp, tearing or ripping pain in the chest radiating to the shoulders or back.
    • Widened mediastinum on x-ray suggests rupture, requiring immediate surgical intervention.

EKG Lead Interpretation

  • Lateral Leads (I, AvL, V5, V6) → Circumflex artery.
  • Inferior Leads (II, III, AvF) → Right coronary artery.
  • Septal Leads (V1, V2) → Left anterior descending artery.
  • Anterior Leads (V3, V4) → Left anterior descending artery.

Posted

in

by

angelicasale08

Tags: