Lewis lead for enhancing atrial activity

Lewis lead for enhancing atrial activity

Lewis lead for enhancing atrial activity was described by Lewis T in 1932 [1]. Utility of this lead in bringing out atrial activity to demonstrate atrioventricular dissociation in a case of wide QRS tachycardia has been illustrated by  Bakker AL and colleagues [2].  The original diagram of Lewis lead from his original publication is also reproduced with permission in that article.

Right arm lead wire is placed in the second right intercostal space close to the sternum and left arm lead wire in the fourth right intercostal space close to the sternum. The right arm lead wire will act as the negative electrode and left arm lead wire as the positive electrode and the Lewis lead will be recorded using the lead I of the electrocardiograph.

Indifferent electrode in the right leg and left lower limb electrode in the left leg have no change in positions while recording the Lewis lead. To enhance the visualisation of atrial activity, the recording is done with a calibration of 1 mV = 20 mm. In the original description of Lewis lead, he had used it to enhance the demonstration of atrial fibrillatory waves.

In another case report, they could demonstrate AV association in a case of wide QRS tachycardia by using Lewis lead, thereby excluding ventricular tachycardia [3].

References

  1. Lewis T.  Auricular fibrillation. In: Clinical Electrocardiography. 5th ed. London, UK: Shaw and Sons; 1931:92.
  2. Bakker AL, Nijkerk G, Groenemeijer BE, Waalewijn RA, Koomen EM, Braam RL, Wellens HJ. The Lewis lead: making recognition of P waves easy during wide QRS complex tachycardia. Circulation. 2009;119:e592-3.
  3. Lewis lead enhances atrial activity detection in wide QRS tachycardia. J Emerg Med. 2012;43:e97-9.