SILENT - Subclinical AtrIal FibrilLation and StrokE PreveNtion Trial "SILENT"

Not yet recruiting

Phase 4 Results N/A

Trial Description

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 the 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.



  • Anticoagulant by physician criteria Drug
    Intervention Desc: 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.
    ARM 1: Kind: Experimental
    Label: anticoagulant by physician criteria

Trial Design

  • Allocation: Randomized
  • Masking: Open Label
  • Purpose: Treatment
  • Endpoint: Safety/Efficacy Study
  • Intervention: Parallel Assignment


Type Measure Time Frame Safety Issue
Primary Stroke 36 months No
Primary Systemic embolism 36 months No
Secondary Subclinical AF rate 36 months No
Secondary Total mortality 36 months Yes
Secondary Cardiovascular mortality 36 months Yes
Secondary Myocardial infarction 36 months No
Secondary Cardiovascular hospitalization 36 months Yes
Secondary Bleeding rates 36 months Yes