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Right Atrial hypertrophy


Left Atrial hypertrophy


Right Ventricular Hypertrophy



Left Ventricular Hypertrophy



Myocardial infarction :


Significant Q wave with typical ST segment elevation in the same lead.


  • Significant Q wave
  • Diminished R wave
  • Twave inversion
  • ST segment elevation


Only characteristic abnormalities of the QRS are found.

  • Significant Q wave
  • Diminished R wave

Myocardial infarction by site:

Location QRS abnormalities Vessel affected
Inferior  II, III, AVF Terminal branches of  LAD and or Right posterior descending
Anteroseptal  V1, V2 Distal LAD
Anterior V1, V2, V3, V4 Proximal  LAD
Anterolateral I, AVL, V4-V6 Distal circumflex
High lateral wall  Lead 1 and AVL Proximal circumflex branch of LCA
True posterior   No Qwaves. Leads showing reciprocal changes only: Tall R waves, tall T waves and ST depression in V1, V2 Posterior descending
Subendocardial Non Q wave infarction
Difficult to establish with certainty
  • ST-T changes with clinical and laboratory evidence of infarct
  • deeply inverted T waves.
  • prolonged QT interval