The SEPTAL-PM study is aimed to compare the right ventricular apical and right ventricular septal position of the right ventricular lead in patients implanted with a pacemaker for conventional anti-bradycardia pacing indications requiring permanent right ventricular pacing ; the primary endpoint is the evolution of the left ventricular ejection fraction assessed by contrast echocardiography at 18-months follow-up.

Classically the right ventricular pacing (RV) lead position is the RV apex. Several small studies suggested that the septal position which provided a more physiological conduction pattern would improve left ventricular function and dimensions and the patients' outcome.

The SEPTAL-PM study is a parallel randomized prospective simple-blinded and multicenter national study with a follow-up duration of 18 month. A total of 180 patients will be enrolled.

It was designed to demonstrate that in patients requiring permanent RV pacing for high degree atrio-ventricular conduction disorders the septal pacing would preserve the LVEF and LV dimensions but also the quality of life and the exercise tolerance.

The primary endpoint is the evolution of the LVEF assessed by contrast echocardiography. The secondary endpoints are: the quality of life SF 36 questionnaire, the NYHA class, the 6-minute-walk test, the QRS duration, the LV end-systolic and diastolic volumes, the NT-pro BNP, MMP 2-9 and TIMP-1 dosages, stimulation and detection ventricular thresholds.

Other reported parameters are: the probes position and electric parameters, all causes of mortality, cardiovascular mortality, hospitalisations for cardiovascular causes, serious adverse events.

Inclusion Criteria:

• Age over 18 years old.
• Written informed consent.
• Permanent cardiac pacing indication for high degree AV block with ventricular rate less than 50 bpm according to the current guidelines of the European Society of Cardiology .
• Patients with sinus rhythm or permanent atrial fibrillation.

Non-inclusion Criteria:

• Indication for cardiac resynchronization.
• Indication for Intra cardiac defibrillators (ICD).
• Indication for AV node ablation for patients with atrial fibrillation.
• Patients already implanted with a pacemaker or an ICD.
• Myocardial infarction within the previous month.
• Surgically treated valvulopathy.
• Tricuspid Valve prothesis
• Cardiac surgery or coronary revascularization planned or within the 3 last months.
• Life expectancy less than 18 months.
• Pregnancy.
• Disability to give informed consent.