title: Role of a 12-lead electrocardiogram in the diagnosis of cardiac tamponade as diagnosed by transthoracic echocardiography in patients with malignant pericardial effusion.
abstract: BACKGROUND
  Few studies have looked at the utility of the 12-lead electrocardiogram (ECG) in diagnosing cardiac tamponade in malignant pericardial effusion (PE). The aim of this study was to determine the sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) of 12-lead ECG in diagnosing cardiac tamponade in PE.
  
  
  OBJECTIVE
  Abnormalities on a 12 lead ECG can be used to diagnose or exclude cardiac tamponade in patients with malignant PE.
  
  
  METHODS
  Using echocardiography as the gold standard for diagnosis of cardiac tamponade, we determined the Se, Sp, PPV, and NPV for individual and combinations of the 3 ECG abnormalities (low-voltage complexes, electrical alternans, and sinus tachycardia).
  
  
  RESULTS
  For PEs of all sizes, the Se, Sp, PPV, and NPV for detecting cardiac tamponade were: low-voltage complexes (56%, 74%, 81%, 46%), electrical alternans (23%, 98%, 95%, 39%), and sinus tachycardia (76%, 60%, 79%, 56%), respectively. Presence of all 3 and any of the 3 ECG abnormalities had a Se, Sp, PPV, and NPV of 8%, 100%, 100%, 36% and 89%, 47%, 77%, 69%, respectively, for cardiac tamponade. The odds ratios for cardiac tamponade in PE were 3.7 (95% confidence interval [CI]: 1.65-8.30) for low-voltage complexes, 12.3 (95% CI: 1.58-95.17) for electrical alternans, and 4.9 (95% CI: 2.22-10.80) for sinus tachycardia. Presence of any of 3 ECG abnormalities had an odds ratio of 7.3 (95% CI: 2.9-18.1) for cardiac tamponade.
  
  
  CONCLUSIONS
  In malignant PE, combination of ECG abnormalities can supplement clinical examination in the diagnosis of echocardiographic cardiac tamponade. Due to its low NPV, 12-lead ECG cannot be used as a screening tool to exclude cardiac tamponade with malignant PE.
authors.affiliation: Department of Cardiology, University of Texas MD Anderson Cancer Center, Houston, Texas; Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, South Carolina.
authors.forename: Rahul G
authors.initials: RG
authors.lastname: Argula
authors.forename: Smita I
authors.initials: SI
authors.lastname: Negi
authors.forename: Jose
authors.initials: J
authors.lastname: Banchs
authors.forename: Syed Wamique
authors.initials: SW
authors.lastname: Yusuf
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002305:Cardiac Tamponade / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D003430:Cross-Sectional Studies; D018618:Echocardiography, Doppler, Color; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D016017:Odds Ratio; D010490:Pericardial Effusion / Q000209:etiology*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult