Download Cardiac Tamponade - Jefferson EM Ultrasound

Cardiac
Tamponade
JONATHAN E KARADEMOS, MD
EMERGENCY MEDICINE, PGY-1
THOMAS JEFFERSON UNIVERSITY HOSPITAL
Objectives
 What
 How
is Cardiac Tamponade
does it happen
 Clinical
Findings
 Timing
 Ultrasound
Findings
What is it?
 Slow
or rapid compression of the heart
due to pericardial accumulation of fluid or
gas.
 Leads
to hemodynamic instability.
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.
Beck’s Triad

Hypotension

Jugular Venous Distension

Muffled/Distant Heart Sounds
Beck’s Triad

Hypotension

Jugular Venous Distension

Muffled/Distant Heart Sounds

Present in 1/3 of cases
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)
Timing Is Key
 Acute
 Subacute
 Low
pressure (occult)
 Regional
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
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.
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.
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)
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
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
Mitral Valve Inflow
Treatment

IV Fluids

Pericardiocentesis

Scope of another lecture
Conclusions

Signs and symptoms can be nonspecific

US is a beneficial tool in the confirmation of cardiac
tamponade

Ultimately, a clinical diagnosis
References

Spodick, David H., M.D.,D.Sc. “Acute Cardiac Tamponade” N Engl J Med
2003;349:684-90

”Cardiac Tamponade”. Sinai EM Ultrasound.
http://sinaiem.us/2012/01/30/cardiac-tamponade/ 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. 2016.

”Diagnosis and Treatment of Pericardial Effusion”. UpToDate.
http://bit.ly/2hlNGZa Accessed 11 Dec 2016.

”Tamponade”. Standford Univeristy: Echocardiography in ICU.
https://web.stanford.edu/group/ccm_echocardio/cgibin/mediawiki/index.php/Tamponade Accessed 11 Dec 2016.

Diastology archives. (2016, September 30). Retrieved October 3, 2016, from
Ultrasound Podcast, http://www.ultrasoundpodcast.com/tag/diastology/