Introduction:

Regardless of the type of electrical stimulation (VVI or DDD) the highest percentage of right ventricular apical pacing can cause left ventricular failure. For this reason, studies have been performed in different sites on right ventricle pacing.

Objective:

To describe differences between electrocardiography and echocardiography variables during right ventricular apical pacing and septal pacing.

Methods:

A total of 24 patients were studied, 2 women and 22 men, with heart failure due to conventional pacing on right ventricular (ejection fraction ≤ 35%). An electrocardiogram as well as an echocardiogram, was performed during right ventricular apical pacing and when patients were paced on septal area.

Results:

The ejection fraction increased from 31 ± 3.1% to 45 ± 12% (P=.0041) on septal pacing, showing higher degree of mechanic synchronisation.

Conclusions:

Pacing on septal area could be a good site for those patients that suffer heart failure due to right ventricular apical pacing. These must show narrow QRS on their intrinsic electrocardiographic conduction. This kind of pacing can produce an improvement in electro- mechanical synchronisation, as well as show an increased left ventricular ejection fraction.