Prevention of Syncope by Cardiac Pacing in Patients With Bifascicular Block

Prevention of Syncope by Cardiac Pacing in Patients With Bifascicular Block

Study Objective

The purpose of this study is to evaluate the efficacy of bradycardia pacing with respect to patient symptoms in patients with bifascicular block and syncope of unexplained origin.

Primary endpoint

First occurrence of a composite of Syncope of any origin OR Presyncopal episode with documented cardioinhibitory origin OR Atrioventricular block of any degree; all associated with patient symptoms

Design:

• Randomized, prospective, single blinded, two parallel arms
• Treatment group : DDD60 - programmed in DDD mode / 60 lower limit
• Control Group: DDI30 - programmed in DDI mode / 30 lower limit
• Randomization type: block randomization: Block size: 4, allocation ratio 1:1

Sample: 100 patients

Population

• Patients with bifascicular block with at least one syncopal episode within the last 6 months preceding enrollment.
• Patients should be negative to a series of pre-enrollment screening in order to exclude:
• Brady-tachy syndrome, vasovagal syncope or carotid sinus syndrome, atrial fibrillation, inducible AV block
• Ejection fraction >=40%
• Mean nocturnal heart rate >=35 bpm

Inclusion Criteria:

• Evidence of Bifascicular block
• At least one episode of syncope during last 6 months from the enrollment

Exclusion Criteria:

• Patients with Brady-tachy syndrome that needs of pacemaker to prevent the symptomatic bradycardia o symptomatic tachycardia arrhythmia
• Patients with vasovagal syndrome by positive TTT or carotid sinus syndrome
• Patients with Chronic Atrial Fibrillation
• Patients with Atrial Ventricular Block induces at EPS