Cardiac Tamponade
Definition
Pericardial effusion, which usually has accumulated rapidly; leading elevation of venous pressure and pulsus paradoxus. An increase in pericardial pressures leads to impaired cardiac filling and, thus, decreased cardiac output.
Etiology
- Malignant disease (32% )
- Idiopathic pericarditis (14%)
- Uremia (9%)
- Acute myocardial infarction (receiving heparin) (9%)
- Diagnostic procedures with cardiac perforation (7.6%)
- Bacterial (7. 5%)
- Tuberculosis (5%)
- Radiation (4%)
- Myxedema (4%)
- Dissecting aortic aneurysm (4%)
- Post-pericardiotomy syndrome (2%)
- Systemic lupus erythematosus (2%)
- Cardiomyopathy (2%)
Signs and Symptoms
- Dyspnea, Tachypnea
- Jugular venous distention
- Pulsus paradoxus
- Hepatomegaly
- Chest pain
- Anuria
- Weakness
- Cold extremities
- Cyanosis
Complications
- Hypotension
- Shock
Cardiac Auscultation
- Diminished heart sounds
- Pericardial friction rub
- Electrocardiogram
- May appear normal
- Generalized low voltage may be present
- ST-T wave elevation present in all leads except AVR and V1
- Electrical alternans
- Rhythm disturbances (atrial fibrillation, atrial flutter, tachycardia)
Chest X-ray
- May demonstrate normal-sized heart
- Cardiomegaly
Treatment
- Pericardiocentesis
- Pericardial window
- Pericardiectomy
M-Mode
- Pericardial effusion
- Right ventricular compression (an RVIDd < 7mm)
- Early diastolic "notch" of the right ventricle
- Increased RVIDd with inspiration on the average of 1 cm
- Decreased LVIDd with inspiration on the average of 1 cm
- Reciprocal change in left/right ventricular dimension; (> 1 cm) with respiration
- Decreased mitral valve E-F slope with inspiration (≤ 50 mm/sec)
- Decreased mitral valve D-E amplitude with inspiration (average decrease 6. 1 mm)
- Delay of mitral valve opening with inspiration
- Decreased left ventricular ejection time with inspiration
2-D
- Pericardial effusion
- "Swinging heart" motion pattern
- Right ventricular diastolic collapse in early diastole
- Right atrial diastolic collapse (late diastole and/or early systole lasting at least one-third of the cardiac cycle)
- Left atrial diastolic collapse in late diastole and early systole
- Left ventricular diastolic collapse
- Inspiratory "bounce" of the interventricular septum toward the left ventricle-with inspiration
- Dilated inferior vena cava (normal 1. 2 to 2. 3 cm) with lack of inferior vena cava collapse (normal collapse > 50%) upon inspiration
PW Doppler
- Right-to-left shunt through a patent foramen ovale
- Increased IVRT with inspiration
- Decreased left ventricular ejection time with inspiration,
- Marked (> 25%) respiratory variation of tricuspid (increase with inspiration) and mitral (decrease with inspiration) flow velocities and time velocity integrals
- Marked (> 25%) respiratory variation of pulmonic (increase with inspiration) and aortic (decrease with inspiration) flow velocities and time velocity integrals
- Limitation of right heart filling by hepatic venous Doppler:
- Normal inspiratory increase in systolic (S wave) and diastolic (D wave) forward flows; systolic is greater than diastolic
- Normal inspiratory decrease of atrial reverse (AR wave) and systolic reverse (VR wave) flows
- Marked decrease or reversal of diastolic forward flow in expiration
- Prominent atrial reversal (AR wave) of flow during expiration
- Reversal of flow in systole in expiration (less common)