Subclinical AtrIal FibrilLation and StrokE PreveNtion Trial

Study Overview
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Brief Summary
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Introduction: Patients with atrial fibrillation (AF) have a substantial risk of stroke and systemic embolism. Subclinical AF is often suspected to be the cause of stroke in these patients. The detection of asymptomatic AF episodes is a challenge and the real rate of occurrence of these episodes remains unknown. The rate of stroke is high among patients who have received a pacemaker and this device can detect subclinical episodes of rapid atrial rate, which correlate with electrocardiographically documented AF. The net benefit of anticoagulant treatment is well established in patients with clinical AF but data about anticoagulation in subclinical AF setting is unknown. The aim of this study is to assess the impact of anticoagulant therapy on subclinical AF, directed by cardiac implantable electronic device (CIED) intensive monitoring, on the incidence of stroke and systemic embolism and correlate the AF episodes detected by CIED with thromboembolic events. Methods: This is a prospective, randomized, unicentric, parallel clinical study in patients with atrioventricular pacemaker, defibrillator, or cardiac resynchronization therapy devices in sinus rhythm and CHADS2 score (an index of the risk of stroke in patients with atrial fibrillation, range from 0 to 6) ≥ 2 . Patients will be randomized to the intervention group - intensive monitoring arm (Group I) or control group - routine schedule arm (Group II) in a 1:1 ratio. Time to inclusion will be 24 months and all patients will be followed up for a period of 36 months. Group I, patients will be submitted to device data collection every 2 months, while in Group II, patients will be managed conventionally. Patients from Group I with episodes of subclinical AF will receive anticoagulant therapy, as well as patients with clinical AF of both arms. Device data from Group II patients will not be analyzed until they achieve the primary endpoint. Primary endpoint: stroke or systemic embolism. Secondary endpoints: subclinical AF rate, total mortality, cardiovascular mortality, myocardial infarction, cardiovascular hospitalization, and bleeding rates. Expected outcome: It is expected that anticoagulation therapy of subclinical AF directed by CIED intensive monitoring will reduce the incidence of stroke and systemic embolism comparing to patients with non-diagnosed subclinical AF.

Detailed Description
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Patients with atrial fibrillation (AF) have a substantial risk of stroke and systemic embolism. Subclinical AF is often suspected to be the cause of stroke in these patients. The detection of asymptomatic AF episodes is a challenge and the real rate of occurrence of these episodes remains unknown. The rate of stroke is high among patients who have received a pacemaker and this device can detect subclinical episodes of rapid atrial rate, which correlate with electrocardiographically documented AF. The net benefit of anticoagulant treatment is well established in patients with clinical AF but data about anticoagulation for subclinical AF settings is unknown. The aim of this study is to assess the impact of anticoagulant therapy on subclinical AF, directed by cardiac implantable electronic device (CIED) intensive monitoring, on the incidence of stroke and systemic embolism and correlate the AF episodes detected by CIED with thromboembolic events. Methods: This is a prospective, randomized, unicentric, parallel clinical study in patients with an atrioventricular pacemaker, defibrillator, or cardiac resynchronization therapy devices in sinus rhythm and CHADS2 score (an index of the risk of stroke in patients with atrial fibrillation, range from 0 to 6) ≥ 2 . Patients will be randomized to the intervention group - intensive monitoring arm (Group I) or control group - routine schedule arm (Group II) in a 1:1 ratio. Time to inclusion will be 24 months and all patients will be followed up for a period of 36 months. Group I, patients will be submitted to device data collection every 2 months, while in Group II, patients will be managed conventionally. Patients from Group I with episodes of subclinical AF will receive anticoagulant therapy, as well as patients with clinical AF of both arms. Device data from Group II patients will not be analyzed until they achieve the primary endpoint. Primary endpoint: stroke or systemic embolism. Secondary endpoints: subclinical AF rate, total mortality, cardiovascular mortality, myocardial infarction, cardiovascular hospitalization, and bleeding rates. Expected outcome: It is expected that anticoagulation therapy of subclinical AF directed by CIED intensive monitoring will reduce the incidence of stroke and systemic embolism comparing to patients with non-diagnosed subclinical AF.

Official Title
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SILENT - Subclinical AtrIal FibrilLation and StrokE PreveNtion Trial

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: Anticoagulant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age >= 18 years CHADS2 score >=2 Sinus rhythm Cardiac Implantable Electronic Device Exclusion Criteria: Atrial fibrillation Severe heart valve disease Anticoagulation therapy Pregnancy

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 |
| --- | --- |
| Active Comparator: anticoagulant<br>Prescription of oral anticoagulation for patients with silent AF (detected by the pacemaker). | Drug: Anticoagulant<br>* Anticoagulant treatment will be started in case of subclinical atrial fibrillation (>5,5 hours per day) be diagnosed by cardiac implantable electronic device at intervention group, or clinical atrial fibrillation in both groups.<br>* Other names: Oral Anticoagulant;|
| No Intervention: Control<br>Patients with silent FA detected only by the pacemaker will no receive oral anticoagulation. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stroke | Occurrence of stroke | 36 months | 
| Systemic embolism | Occurrence of systemic embolism | 36 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Subclinical AF rate | Rate subclinical AF documentation by pacemaker | 36 months | 
| Total mortality | All cause mortality | 36 months | 
| Cardiovascular mortality | Adjudicated cardiovascular mortality | 36 months | 
| Myocardial infarction | Occurrence of myocardial infarction | 36 months | 
| Cardiovascular hospitalization | Adjudicated cardiovascular hospitalization | 36 months | 
| Bleeding rates | Occurrence of bleeding | 36 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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atrial fibrillation, stroke, pacemaker, anticoagulant