We report a prospective and descriptive study in 12 patients who had pacemaker implantation from may. 1996 and dec. 1997. Our patients benefited from complete clinical examination, ECG (12 derivations), standard laboratory tests, chest X ray. Pulsed-Doppler, two dimensional and TM echocardiography have been performed. Stimulation was achieved using endocardial lead introduced percutaneously. During the study, 12 patients over 22, representing 55% of the subjects with symptomatic conduction defects, had definitive pacemaker implantation. Mean age was 53.8 years +/- 18. Most of the patients lived in Dakar. Sex-ratio was 0.58 (7 males/5 females). Most of the patients (83%) had low socio-economical status. Before implantation mean heart rate was 47 bpm +/- 20.8. Mean blood pressure was 155 mmHg +/- 26.7 (systolic) and 71.6 +/- 20.8 mmHg (diastolic). Heart failure was present in 5 patients/12. Others symptoms were mainly syncope (83%). Mean cardiothoracic ratio was 0.56 +/- 0.09. Over a 14 months period we have implanted 7 double chamber stimulators (DDD) and 5 monochamber (VVI). Over a 210 days follow-up, main problems are infection of the pocket in 2 patients. In one of them culture was positive. In Senegal, it is necessary to develop cardiac stimulation. Pacemakers should be available for all patients with symptomatic conduction defects. A national center for electrophysiologic studies and pacemaker implantation is a priority.