Prevention of Syncope by Cardiac Pacing in Patients With Bifascicular Block

Study Overview
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Brief Summary
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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.

Detailed Description
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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

Official Title
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Prevention of Syncope by Cardiac Pacing in Patients With Bifascicular Block

Conditions
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Bifascicular Block, Syncope

Intervention / Treatment
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* Device: DDD60 (INSIGNIA® pacing systems Guidant (Boston Scientific)
* Device: DDD60 (INSIGNIA® pacing systems Guidant (Boston Scientific)


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: DDI30<br>Control group based only on backup pacing with lower rate 30 ppm | Device: DDD60 (INSIGNIA® pacing systems Guidant (Boston Scientific)<br>* pacing in DDDI30 is supposed to act as a safety backup upfront to episodes of syncope, presyncope or AV block, but not supposed to reduce symptoms.<br>* Other names: INSIGNIA® pacing systems Guidant (Boston Scientific);|
| Active Comparator: DDD60<br>Treatment arm based on full pacing support (60 Lower Rate) | Device: DDD60 (INSIGNIA® pacing systems Guidant (Boston Scientific)<br>* pacing in DDD60 is supposed to prevent events of syncope, presyncope of cardioinhibitory origin and symptom associated to av block<br>* Other names: INSIGNIA® pacing systems Guidant (Boston Scientific);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Combined Endpoint Defined as First Occurrence Among the Following Events 1)Syncope Episode of Any Origin; 2)Presyncopal Episode With Documented Cardioinhibitory Origin 3) Atrioventricular Block of Any Degree Associated With Patient Symptoms | Number of participants experiencing syncope episodes, symptomatic pre-syncopal episodes associated with a device intervention (ventricular pacing) and symptomatic episodes associated with documentation of intermittent or permanent atrio-ventricular block | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of First Symptomatic Episode (Syncope or Pre-syncope), Independently From Origin. |  | 2 years | 
| Atrial Fibrillation | patients presenting with at least one episode of atrial fibrillation during the 2 years follow up period | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Syncope, Bifascicular block, Bradycardia pacing