Cardiac Tamponade

Author: Michelle Lin, MD
Updated: 7/8/2011

Cardiac Tamponade

Definition: Clinical state where pericardial fluid compresses the heart and compromises cardiac output.

Normal pericardial fluid volume: 15-30 mL

Echocardiography findings

  • RA systolic collapse
  • RV diastolic collapse
  • IVC plethora
  • Exaggeration of respirophasic changes in flow velocities across TV and MV

Systematic review of 8 studies with a total of 300 patients

Finding Sensitivity Specificity (+) Likelihood Ratio (-) Likelihood Ratio
Clinical history | |
- Dyspnea 87-88% |
Physical exam | |
- Tachycardia 77% |
- Hypotension 26% |
- Diminished heart sounds 28% |
- Elevated JVP 76% |
ECG | |
- Low voltage 42% |
- Electrical alternans 16-21% |
- ST elevation 18-30% |
- PR depression 18% |
Chest xray | |
- Cardiomegaly 89% |
Pulsus paradoxus | |
- >12 mmHg 98% 83% 5.9 0.03
- >10 mmHg 98% 70% 3.3 0.03

Use below Fagan nomogram

Fagan Nomogram

Fagan Nonogram

  • Draw a connecting your pre-test probability and your likelihood ratio.
  • This provides you with your post-test probability.

References

  • Roy CL et al. Does This Patient With a Pericardial Effusion Have Cardiac Tamponade? JAMA. 2007;297:1810-8. [PubMed]