1. Cardiac Tamponade Jonathan E Karademos, MD Emergency Medicine, PGY-1
Thomas Jefferson University Hospital

2. Objectives What is Cardiac Tamponade How does it happen
Clinical Findings
Timing
Ultrasound Findings

3. What is it?
Slow or rapid compression of the heart due to pericardial accumulation of fluid or gas.
Leads to hemodynamic instability.

4. Pathophysiology Increasing intrapericardial pressure
Pericardium stretches until reserve volume is exceeded (happens slowly and It is why acute effusions are so dangerous)
The heart then must compete with the increasing pericaridal contents within a fixed space.
Heart chambers become smaller, diastolic compliance is reduced.
Venous return progressively shifted to systole as the peak associated with early diastolic filling diminishes.
Progressively worse as pericardial pressure becomes higher than ventricular diastolic pressures.

5. Beck’s Triad Hypotension Jugular Venous Distension
Muffled/Distant Heart Sounds

6. Beck’s Triad Hypotension Jugular Venous Distension
Muffled/Distant Heart Sounds
Present in 1/3 of cases

7. Clinical Findings Nonspecific symptoms and physical exam findings
Tachypnea
Dyspnea on Exertion progressing to air hunger at rest
Tachycardia
Muffled heart sounds
Hypotension
Shock (cool extremities in rapid tamponade)
Jugular venous distension
Pulsus paradoxus (inspiratory drop in systolic pressure of 10 mm Hg).
Pericardial Rub (if inflammatory cause)
Tachycardia in all except early tamponade and hypothyroidism

8. Timing Is Key
Acute
Subacute
Low pressure (occult)
Regional

9. Lab Studies
CXR: Need 200ml of fluid before cardiac silhouette is affected
Lateral may show pericardial-fat lines (uncommon but specific)
EKG: Sinus tachycardia
May show electrical alternation
Low voltages
Echocardiography: Principle tool for diagnosis. CT
MRI: Takes too long
Low voltages: present in 60% with tamponade but not present w/o.

10. Signs on Ultrasound
Presence of pericardial effusion (there are exceptions)
Chamber collapse
Right atrial wall during end diastole
Right ventricular collapse during early diastole
Left atrium
Left Ventricle (most specific)
IVC dilation with loss of respiratory variations
Respiratory variations >25% in mitral, aortic, and/or tricuspid flow.
Exceptions: Mediastinal Mass or Large b/l pleural effusions

11. Pericardial Effusion Anechoic stripe surrounding heart.
50 mL of fluid, acutely, can cause tamponade
Small effusions will not surround the heart and can be seen in the most dependent area of the pericardial space.
Can be loculated (post-Cardiac surgery patients)
Pericardial fat pad appears as isolated anechoic area with brighter speckles on anterior surface.
Don’t confuse with pleural effusions.

12. Pericardial and Pleural Fluid

13. Chamber Collapse
Make sure it is during diastole (opening of mitral valve)
With increasing pericardial pressures, the lower pressures on the right side of the heart are affected first.
Can use M-mode with cursor across anterior leaflet of mitral valve and across either right atrial or ventricular free wall.
Left atrial collapse seen in 25% with hemodynamic compromise (very specific)

17. IVC Dilation Sign of increased central venous pressure (CVP)
IVC that is greater than 2 cm and collapses less than 50% with inspiration (forced sniff), correlates with CVP greater than 10 cm H2O
Present in majority of patients requiring pericardial drainage
Highly sensitive but not specific

20. Mitral Valve Inflow
Normal variation in flow across valves due to respiratory cycles.
During inspiration, septa move leftward. Reversed during expiration.
During cardiac tamponade, this variation in blood flow is exaggerated.
Can measure velocities of flow across valves (best in apical view).
During cardiac tamponade:
Mitral flow variation usually exceeds 30%
Tricuspid valve flow usually exceeds 60%
Measured in first beat of inspiration and expiration.
Can be obscured in severe hypovolemia or right ventricular hypertrophy

22. Mitral Valve Inflow
Ultrasound Podcast

24. Treatment
IV Fluids
Pericardiocentesis
Scope of another lecture

25. Conclusions Signs and symptoms can be nonspecific
US is a beneficial tool in the confirmation of cardiac tamponade
Ultimately, a clinical diagnosis

26. References
Spodick, David H., M.D.,D.Sc. “Acute Cardiac Tamponade” N Engl J Med 2003;349:684-90
”Cardiac Tamponade”. Sinai EM Ultrasound. Accessed 7 Dec 2016.
Goodman, Adam et al. “The Role of Bedside Ultrasound in the Diagnosis of Pericardial Effusion and Cardiac Tamponade.” Journal of Emergencies, Trauma, and Shock 5.1 (2012): 72–75. PMC. Web. 10 Dec
”Diagnosis and Treatment of Pericardial Effusion”. UpToDate. Accessed 11 Dec 2016.
”Tamponade”. Standford Univeristy: Echocardiography in ICU. bin/mediawiki/index.php/Tamponade Accessed 11 Dec 2016.
Diastology archives. (2016, September 30). Retrieved October 3, 2016, from Ultrasound Podcast,