Diagnostic Significance of a Small Q Wave in Precordial Leads V2 or V3
Article first published online: 12 APR 2010
©2010, Wiley Periodicals, Inc.
Annals of Noninvasive Electrocardiology
Volume 15, Issue 2, pages 116–123, April 2010
How to Cite
Katsuno, T., Hirao, K., Kimura, S., Komura, M., Haraguchi, G., Inagaki, H., Hachiya, H. and Isobe, M. (2010), Diagnostic Significance of a Small Q Wave in Precordial Leads V2 or V3. Annals of Noninvasive Electrocardiology, 15: 116–123. doi: 10.1111/j.1542-474X.2010.00351.x
- Issue published online: 12 APR 2010
- Article first published online: 12 APR 2010
- coronary artery disease;
- coronary angiography
Background: An abnormal Q wave is usually defined as an initial depression of the QRS complex having a duration of ≥40 ms and amplitude exceeding 25% of the following R wave in any contiguous leads on the 12-lead electrocardiogram (ECG). However, much smaller Q waves are sometimes recorded on the ECG. This study investigated the diagnostic value of the small Q wave recorded in precordial leads V2 or V3 on the ECG.
Methods: We investigated 807 consecutive patients who underwent coronary angiography. A small Q wave was defined as any negative deflection preceding the R wave in V2 or V3 with <40-ms duration and <0.5-mV amplitude, with or without a small (<0.1-mV) slurred, spiky fragmented initial QRS deflection before the Q wave (early fragmentation). ECG and coronary angiographic findings were analyzed.
Results: The small Q wave was present in 87 patients. Multiple logistic regression analysis revealed that presence of a small Q wave was a strong independent predictor of any coronary artery stenosis or left anterior descending artery (LAD) stenosis (odds ratio = 2.706, 2.902; P < 0.001, < 0.001, respectively).
Conclusion: A small Q wave (<40-ms duration and <0.5-mV amplitude) in V2 or V3 with or without early fragmentation significantly predicted the presence of CAD and, especially, significant stenosis in the LAD.
Ann Noninvasive Electrocardiol 2010;15(2):116–123