1 - ECG Hallmarks Flashcards
1
Q
What are the ECG hallmarks of V-Tach?
A
- Northwest axis — QRS is positive in aVR, negative in I and aVF
- The taller left rabbit ear sign — There is an atypical RBBB pattern in V1, where the left “rabbit ear” is taller than the right.
(* This is the most specific finding in favour of VT.*) - Negative QRS complex (R/S ratio < 1) in V6
2
Q
When you see a regular narrow complex tachycardia at 150 bpm, you should think of four main diagnoses:
A
• Atrial flutter with 2:1 block (especially in elderly, IHD, CCF)
• AV-nodal reentry tachycardia (“SVT”)
• Orthodromic AV reentry tachycardia in WPW
- Orthodromic -
• Sinus tachycardia — should see P waves but may be hidden in the T waves (e.g. with concurrent 1st degree AV block). There should also be some HR variability compared to the other 3 rhythms.