© 2002 European Society of Cardiology
Distinct left bundle branch block pattern in ischemic and non-ischemic dilated cardiomyopathy
a Servei de Cardiologia, Hospital de la Santa Creu i Sant Pau C/ San Antonio Ma Claret 167, 08025 Barcelona, Spain
b Institut Municipal d'Investigacions Mèdiques Barcelona, Spain
* Corresponding author. Tel.: +34-93-291-92-94; fax: +34-93-291-94-24 E-mail address: abayesgenis{at}hsp.santpau.es
 |
Abstract |
|---|
Background: A high percentage of patients with dilated cardiomyopathy have the electrocardiographic (ECG) pattern of advanced left bundle branch block (LBBB). In the present study we sought to investigate whether patients with dilated cardiomyopathy of ischemic or non-ischemic etiology can be differentiated on the basis of LBBB pattern.
Methods and Results: The study population included 41 patients with dilated cardiomyopathy of non-ischemic (NIC) (n=26) or ischemic origin (IC) (n=15) and LBBB on surface ECG. ECG duration and voltage were digitally measured. The presence of notching of S wave in right precordial leads (V1–V3) was not statistically different between the groups. The voltages of precordial leads V2, V3 and the 
(V1+V2+V3 voltages) were significantly more prominent in patients with NIC (P=0.002, P<0.001 and P=0.002, respectively). The discriminative power of receiver operating characteristic analysis was best at voltages of V3 of 2100 µV (area under the curve, 0.805; standard error, 0.001). The sensitivity and specificity of V3 voltage >2100 µV on surface ECG in the presence of LBBB to identify a cardiomyopathy of non-ischemic origin were 85 and 73%, respectively.
Conclusions: A single ECG criteria, voltage of lead V3, appears to be a useful parameter to identify patients with dilated cardiomyopathy of ischemic or non-ischemic origin in the presence of advanced LBBB.
Key Words: Left bundle branch block • Electrocardiogram • Dilated cardiomyopathy
Received May 24, 2002; Revised July 18, 2002; Accepted October 4, 2002