Bipolar vs. Unipolar voltage mapping of AF ablation
We are contemplating the utility of the unipolar electrogram for assessing low-voltage areas. The result may help to judge how we should perform AF ablation, especially in patients with HF. Ablation of low-voltage areas in the left atrium (LA) has been reported as having therapeutic value for maintaining sinus rhythm.11 On the other hand, bipolar voltage criteria may be affected both by the activation direction of the superficial atrial activation and by insufficient contact with the endocardial tissue. There may also be differences in the visibility due to specific features of the mapping catheter (i.e., size of the electrodes, distance between the electrodes, etc.). In the near future, advanced atrial remodeling evaluated by unipolar electrograms (Figure) may show an important cause of atrial arrhythmias.