Q waves: Discussion


* Normally found in leads: I, AVL, V6, (V5); 
- Normal if < 1/2 mm wide or < 0.025 sec; 
- Do to Septal depolarization; 
- Ignore Q waves in AVR; * Pathologic Q waves: 
- Abnormal in V2, V3; 
- Greater than 0.03-0.04 sec and/or 1/4 R wave; * Transmural MI: Q waves seen after 24-48 hrs; * Q1, QaVL, S3 (or small RIII): 
- consider Anterior Hemiblock * Q3 (small), S1 (small R in I); 
- consider Post HemiBlock * Q3/Large S1: consider Pulmonary Infarct * * Non Classical Myocardial infarct Q waves/QS complexes; 
- Left BBB: QS in V1, V2; 
- COPD: QS in V1-V3; 
- Muscular Dystrophy; 
- LVH: (2nd to AI): QS in V1-V4; 
- IHSS: may have inferolateral q waves: 
- WPW: depending on the tract may have q waves; 
- Caridac Tamponade: Elect Alternans pattern



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Monday, December 19, 2011 3:20 pm