TABLE 1

Diagnostic Utility of Various Clinical Findings for Cardiac Tamponade

Sensitivity, %Specificity, %Positive Predictive Value, %Subject Age Range, y
Clinical findings
 Tachycardia698779≥18 only
 Tachypnea87–899≥18 only
 JVD138769≥18 only
 Cardiomegaly on CXR899≥18 only
 Pulsus paradoxus >10 mm Hga989709≥18 only
 Hypotension388269≥18 only
 Diminished heart sounds388289≥18 only
ECG findings
 Low voltage76156015811515–95, mean 53
 Electrical alternans23159815951515–95, mean 53
 Sinus tachycardia76156015791515–95, mean 53
 Low voltage + alternans + sinus tachycardia815100151001515–95, mean 53
Echocardiography findings
 Any chamber collapse9016651615–88, mean 53
 Right atrial collapse for greater than one-third of cardiac cycle94171001710–82, mean 52
  • a When seen with a pericardial effusion, likelihood ratio (LR) of tamponade increased by 3.3 times.9