ECG Library


All ECG 153

  1. Normal sinus rhythm
  2. Normal sinus rhythm
  3. Left atrial enlargement
  4. Left anterior fascicular block
  5. ST-T wave abnormality - consider ischemia

This is an ECG from a heart transplant patient. Examine closely the P wave activity in lead II.

When the native heart was explanted, a portion of the right atrium was left intact including the native SA node. A new heart was implanted which also included a SA node. This has resulted in two P waves both of sinus morphology, however at different rates. Only the transplanted SA nodal activity conducts to the ventricle since the surgical anastomotic site creates an electrical block not allowing the native SA node to depolarize the transplanted atrium and thus it is not able to conduct to the transplanted ventricles.

Related Topic Reviews: Left Atrial Enlargement, Left Anterior Fascicular Block