Pericardial effusion and tamponade

Background

(d) Pericardial cavity, part of the inferior mediastinum, in relation to (a) superior mediastinum; (c) pleural cavities; and (e) diaphragm.

Anatomy of the pericardium.

Pericardial pressure-volume relationships in patients who have rapidly (left curve) and gradually (right curve) developed a pericardial effusion. In rapid accumulating effusion (left curve), even a small effusion volume can exceed the limit of parietal pericardial stretch and finally causes a steep rise in pressure. In contrast, slow accumulating effusion (right curve) requires a long time and a large volume to exceed the limit of pericardial stretch because of the activating compensatory mechanisms.

• Always consider in patient with PEA
• Always consider in patient with penetrating trauma anywhere in the cardiac box (80% result in tamponade)
  • Gun shot wounds are less likely to result in tamponade because pericardial defect is larger
  • Right ventricle is the most commonly injured chamber of the heart due to its anatomic location
• Pathophysiology
  • Increased pericardial pressure > decreased RV filling > decreased cardiac output

Etiology

• Hemopericardium
  • Trauma
  • Iatrogenic (misplaced central line)
  • Bleeding diathesis
  • Ventricular rupture (post-MI)
• Non-hemopericardium
  • Cancer - most commonly lung, breast, prostate, or hematologic
    • Melanoma has predilection for heart
    • May be related to radiation, infection, chemotherapy
  • Pericarditis
    • Infectious
    • Uremic (renal failure)
  • HIV complications (infection, Kaposi sarcoma, lymphoma)
  • SLE and other autoimmune or connective tissue disorders
  • Post-radiation
  • Myxedema

Clinical Features

• Chest pain, shortness of breath, cough, fatigue
• CHF-type appearance
• Tachycardia
• Narrow pulse pressure
• Friction rub
• Pulsus paradoxus (dec in BP on inspiration)
• Beck's Triad (33% of patients)
  • Hypotension
  • Muffled heart sounds
  • JVD

Differential Diagnosis

Chest pain

Critical

• Acute coronary syndromes (ACS)
  • STEMI
  • Non-STEMI
  • Unstable angina
• Aortic dissection
• Cardiac tamponade
• Coronary artery dissection
• Esophageal perforation (Boerhhaave's syndrome)
• Pulmonary embolism
• Tension pneumothorax

Emergent

• Cholecystitis
• Cocaine-associated chest pain
• Mediastinitis
• Myocardial rupture
• Myocarditis
• Pancreatitis
• Pericarditis
• Pneumothorax

Nonemergent

• Aortic stenosis
• Arthritis
• Asthma exacerbation
• Biliary colic
• Costochondritis
• Esophageal spasm
• Gastroesophageal reflux disease
• Herpes zoster / Postherpetic Neuralgia
• Hypertrophic cardiomyopathy
• Hyperventilation
• Mitral valve prolapse
• Panic attack
• Peptic ulcer disease
• Pleuritis
• Pneumomediastinum
• Pneumonia
• Rib fracture
• Stable angina
• Thoracic outlet syndrome
• Valvular heart disease
• Muscle sprain
• Psychologic / Somatic Chest Pain
• Spinal Root Compression
• Tumor

Evaluation

Pulsus Paradoxus

• >10mmHg change in systolic BP on inspiration

CXR

Massive pericardial effusion on chest x-ray

• Enlarged cardiac silhouette

ECG

Sinus tachycardia with low QRS voltage and electrical alternans

• Often normal
• Tachycardia (bradycardia is ominous finding)
• Electrical alternans
• Low voltage
  • All limb lead QRS amplitudes <5 mm or I+II+III<15;
  • OR All precordial QRS amplitudes <10 mm or V1+V2+V3<30

Ultrasound

Transthoracic echo of pericardial effusion showing "swinging heart"

Pericardial effusion on ultrasound

Collapse M mode

MV inflow variation

• Pericardial effusion
  • In acute cases, even a relatively small build up of pericardial fluid can lead to hemodynamic compromise
  • Differentiate pericardial effusion from pleural effusion using the parasternal long axis view. Pericardial effusions will have an anechoic stripe between the left atrium and descending thoracic aorta. In a pleural effusion, the stripe will be seen behind the descending thoracic aorta.
• Classical ultrasound findings
  • Diastolic collapse of the right atrium (in atrial diastole)
  • Diastolic collapse of the right ventricle
  • Plethoric IVC (highly sensitive but low specificity)
• Evaluating systolic vs. diastolic phases with M-mode
  • Position in PSL view with M-mode line through where RV appears to collapse
  • Allow M-mode line to pass through where the anterior MV hits the septum in diastole (much like evaluation of EPSS - see Formal echocardiography)
  • The period of time where the anterior leaflet of the mitral valve is open (and closest to the septum) is the period of diastole. Evaluate the anterior free wall of the right ventricle for collapse. The longer period of collapse during diastole is an indicator for advanced tamponade physiology
• Valvular pulsus paradoxus
  • Obtain apical 4-chamber view, place doppler indicator in either MV or TV location
  • Doppler interrogation across the mitral valve will demonstrate exaggerated respiratory variability of transvalvular flow
  • MV inflow respiratory variation, difference from highest velocity to lowest, as a percentage of highest velocity
    • > 25%, likely tamponade physiology
    • > 40% for tricuspid inflow variation
    • Helpful in thickened RV and RA from longstanding pulmonary hypertensive patients

Management

Hemorrhagic Tamponade

• Can occur if ECG read as STEMI/NSTEMI and heparin started
• Pericardiocentesis
  • Temporizing measure until thoracotomy can be performed
• IVF to increase RV volume and maintain preload
• Medications
  • Pressors (temporizing)
  • Avoid preload reducing medications (nitroglycerin, diuretics)

Non-hemorrhagic Tamponade

• IVF bolus of 500-1000 ml (patient is pre-load dependent)
• Pericardiocentesis is definitive treatment
• Dialysis for patients with known renal failure

Disposition

• To OR if traumatic and hemodynamically unstable
• Admit with cardiology/CT surgery consult

See Also

• Pericardiocentesis
• Thoracic Trauma
• Pericarditis
• Cardiac ultrasound

External Links

• Medscape - Cardiac Tamponade