Failure to agree on the electrocardiographic diagnosis of ventricular tachycardia.
OBJECTIVE
To determine the extent of interobserver agreement in the ECG diagnosis of ventricular tachycardia (VT) by using a four-step algorithm and three observers.


METHODS
Simulated emergency department setting from records of an urban university teaching hospital. All ECGs taken in the ED during a 2-year period that showed a QRS duration of more than 120 msec and a heart rate faster than 110 beats per minute were reviewed. ECGs were categorized as demonstrating sinus rhythm (SR), irregular broad-complex tachycardia (I-BCT), or regular broad-complex tachycardia (BCT). Copies of the BCT ECGs and short clinical histories were given to each of three emergency physicians, who used a published, four-step algorithm (the Brugada algorithm) to categorize the BCT ECGs as indicating VT, indicating supraventricular tachycardia with aberrancy (SVT-A), or indeterminate. Interobserver agreement was assessed with the K-statistic.


RESULTS
The records contained 178 ECGs, 88 of which were SR, 63 I-BCT, and 27 BCT. The 27 BCT ECGs were selected for review. The emergency physicians disagreed with each other 22% of the time in differentiating VT from SVT-A (K = .58).


CONCLUSIONS
Application of the algorithm to actual clinical practice in the ED would probably result in the misdiagnosis of a substantial minority of patients having BCT, with potentially serious adverse consequences.
Herbert
M E
ME
Olive View-UCLA Emergency Department, Olive View Medical Center, Sylmar, USA.
Votey
S R
SR
Morgan
M T
MT
Cameron
P
P
Dziukas
L
L
D000328:Adult; D000368:Aged; D000465:Algorithms; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D004562:Electrocardiography / Q000592:standards*; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013617:Tachycardia, Supraventricular / Q000145:classification / Q000175:diagnosis*; D017180:Tachycardia, Ventricular / Q000145:classification / Q000175:diagnosis*