Poor progression of ‘R’ is said to be present if voltage of ‘r’ wave in lead V1 to V4 remains extremely small.
Criteria to diagnosing poor progression of R wave are (both or anyone can be present)
1. R-wave less than 2-4 mm in leads V3 or V
2. Presence of reversed R-wave progression defined as R in V4 less than R in V3 or R in V3 less than R in V2 or R in V2 less than R in V1, or any combination of these
Cause of Poor progression of R wave Common cause is Anterior myocardial infarction Some time this finding is non specific and does not point to any diagnosis, other causes are.
- Left bundle branch block (LBBB), left anterior fascicular block (LAHB), Wolff-Parkinson-White syndrome(WPW syndrome),
- Some times associated with right ventricular hypertrophy RVH (especially that associated with chronic lung diseases)
- Even left ventricular hypertrophy may result in poor R wave progression
- Left sided pneumothorax
- Corrected transposition of the great vessels (CTGA)
- Congenital absence of the pericardium
Points to remember with respect R waves Normally ECG shows ‘rS’ complex in lead V1 and as one move towards left precordial leads ‘qR’ wave become more prominent in other words voltage of ‘S’ wave decreases and that of ‘R’ wave increases This change prominence of From ‘S’ wave to ‘R’ wave happens by V4, in normal people. In some normal individuals, the transition may be seen as early as V2. This is called early transition. If transition is delayed until V4 to V5. than it is called as delayed transition R-wave amplitude in V5 often taller than V6 because of the attenuating effect of the lungs Normally height of “R” wave in lead V3 is greater than 2mm
Labels: ECG, For Doctors