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Cardiac Tamponade. Francesca N. Delling October 17, 2007. Tamponade. Etiology Physiology - comparison with constrictive pericarditis Types of tamponade Diagnosis - clinical presentation, physical exam, EKG, CXR, echo Treatment . Etiologies. Infectious
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Cardiac Tamponade Francesca N. Delling October 17, 2007
Tamponade • Etiology • Physiology • - comparison with constrictive pericarditis • Types of tamponade • Diagnosis • - clinical presentation, physical exam, EKG, CXR, echo • Treatment
Etiologies • Infectious • Viral (coxsackie B, echovirus, influenza) • Bacterial • Others: TB, fungal, toxoplasmosis • Neoplastic • Uremic • Trauma / cardiac surgery / aortic dissection / cardiac procedures • Radiation • Connective tissue disease (RA, SLE, scleroderma) • Myocardial ischemia / infarct • Myxedema • Idiopathic
Physiology • Exaggerated ventricular interaction • During inspiration greater RV inflow and outflow and concurrent decrease in LV size, outflow tract flow velocity profile and mitral valve inflow • During expiration LV filling and LV outflow augmented at the expense of reduced RV volume and Doppler flow velocities
Physiology Normal pericardium Increasing pericardial pressure Increasing filling pressures RVEDP = LVEDP Equalization of diastolic pressures
Comparison with constrictive pericarditis • Features in common - diastolic dysfunction and preserved ventricular ejection fraction - heightened ventricular interaction - increased respiratory variation of ventricular inflow and outflow manifested clinically by pulsus paradoxus (less frequent in constrictive pericarditis) - equally elevated central venous, pulmonary venous, and ventricular diastolic pressures • Distinctive features - tamponade pericardial space is open and transmits respiratory variation in thoracic pressure to heart (pericardium does not see fluctuation in thoracic pressure in constrictive pericarditis) - constrictive pericarditis: venous return does not increase with inspiration. Diminished LV and increased RV volume are 2/2 lesser pressure gradient from the pulmonary veins
Types of tamponade • Acute tamponade - Due to trauma, rupture of the heart or aorta or complication of an invasive diagnostic or therapeutic intervention - Sudden in onset - Hypotension common • Subacute tamponade -Pericardial fluid accumulates slowly - Hypotension with a narrow pulse pressure, reflecting limited stroke volume. However, patients with preexisting hypertension may remain hypertensive due to increased sympathetic activity
Types of tamponade (continued) • Low pressure tamponade - Severely hypovolemic pts (hemorrhage, hemodyalisis, or overdiuresis) intracardiac and pericardial diastolic pressures are only 6 to 12 mmHg fluid challenge usually elicits typical tamponade hemodynamics • Regional tamponade - caused by a loculated, eccentric effusion - typical physical, hemodynamic, and echocardiographic signs of tamponade may be absent
Clinical Presentation • Tachypnea and exertional dyspnea rest air hunger • Weakness • Presyncope • Dysphagia • Cough • Anorexia • (Chest pain)
Physical Exam Findings • Tachycardia • Hypotension shock • Elevated JVP with blunted y descent • Muffled heart sounds • Pulsus paradoxus • (Pericardial friction rub)
JVP and pulsus paradoxus in tamponade Y descent blunted because of limited or absent lated diastolic filling of the right ventricle
Other causes of pulsus paradoxus • Obstructive airway disease • Acute and chronic • Constriction • Restriction • Pulmonary embolism • RV infarction • Circulatory failure
Echocardiography • 2D and M-mode • RV diastolic collapse • RA collapse/inversion • IVC plethora • Doppler • Exaggerated respiratory variation in mitral and tricuspid inflow velocities • Phasic variation in right ventricular outflow tract/left ventricular outflow tract flow • Exaggerated respiratory variation in inferior vena cava flow
Echocardiogram: RVDC • Most commonly involves the RV outflow tract (more compressible area of RV) • Occurs in early diastole, immediately after closure of the pulmonary valve, at the time of opening of the tricuspid valve • When collapse extends form outflow tract to the body of the right ventricle, this is evidence that intrapericardial pressure is elevated more substantially
M-mode Beginning of systole ES DC
M-mode Beginning of systole ES DC
Echocardiogram: RA Inversion • Right atrium normally contracts in volume with atrial systole • In the presence of marked elevation of intrapericardial pressure, RA wall will remain collapsed throughout atrial diastole (early ventricular systole) • Isolated RA inversion occurs during late diastole • Very sensitive but specificity = 86% • Positive predictive value = 50% • RA Inversion Time Index (RAITI) - Calculated by dividing - Using 33% as the threshold • Specificity = 100% • Sensitivity = 94% Total # frames with inversion Total # frames in the cardiac cycle
Peak velocity of mitral inflow varies > 15% with respiration
Peak velocity of tricuspid inflow varies > 25% with respiration
Predictable hierarchy of events Exaggerated respiratory variation of tricuspid inflow Exaggerated respiratory variation of mitral inflow Abnormal right atrial collapse Right ventricular free wall collapse
Instances when echo abnormalities are not seen • Significant RV hypertrophy, usually due to PHTN • Thickening of the ventricular wall due to malignancy, overlying inflammatory response or thrombus in hemorrhagic pericarditis • Low-pressure tamponade (hypovolemic patients)
Echocardiogram: Additional roles • Confirm size of the pericardial effusion • Small defined as < 100 mL • Moderate defined as 100 – 500 mL • Large defined as > 500 mL • Confirm location of the pericardial effusion • Rule out loculated effusions • Assist pericardiocentesis
Assessment of the patient • Insignificant effusion • Flat neck veins • Normal BP, HR, RR, good perfusion • Hemodynamically significant-Compensated • Elevated JVP • Mild paradox, No hypotension or tachycardia • Good perfusion • Mild RV collapse
Assessment of the patient • Hemodynamically Severe-Max Compensation • Elevated JVP • Prominent paradox, Tachycardia • No hypotension-adequate perfusion • Chamber collapse on ECHO • Hemodynamically Severe-Decompensated • Elevated JVP • Tachycardia, tachypnea • Hypotension with paradox • Chamber collapse, swinging heart
Pericardiocentesis • Usually performed if more than 1 cm effusion • Also performed if effusion smaller in the setting of acute trauma and hemodynamic compromise • Pericardial window if need for biopsies and if evidence of coaugulopathy
RB 74 yo male with recently diagnosed adenocarcinoma of undetermined primary who presented to ED on 10/6 with chest pain
RB • BP 125/65, pulsus paradoxus of 12 • JVP 12 cm • PMI located in 5th ICS, distant heart sounds • Faint crackles lung bases
RB • CT chest consistent with large pericardial effusion and moderate compression of right ventricle • Worsened metastatic disease including enlargement of subclavicular, mediastinal, right hilar lymph nodes and pulmonary nodules • Stat echo showing…
10/6 pericardiocentesis • Drainage of 400 cc of bloody fluid • Pre-procedure: pulsus 20 mmHg, cardiac output 3.8 • Post-procedure: pulsus < 10 mmHg, cardiac output 5.0