Atrial Sensing Capability for Better Detection of Atrial Fibrillation

Study Overview
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Brief Summary
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This prospective multi-center randomized controlled study aims to compare atrial fibrillation detection and inappropriate therapy according to activation of atrial sensing capability in patients with implantable cardioverter defibrillator.

Detailed Description
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Implantable cardioverter defibrillators(ICD) therapy has been shown to reduce sudden cardiac death and improve survival in cardiac arrest survivors as well as in heart failure patients with left ventricular dysfunction. Atrial fibrillation (AF) is commonly found in ICD implantation patients up to 50%. AF is an independent predictor of mortality, inappropriate shock, and embolic events. Therefore, early detection of AF in patients with ICD is essential for improving the quality of life and overall prognosis of the patients. Conventional ICDs consist of a single chamber (SC) ICD with a lead only in the right ventricle (RV) and dual chamber (DC) ICD with each lead in the right atrium (RA) and RV. SC ICD has the advantage of shorter procedure time, lower cost compared to DC ICD. In contrast, DC ICD has the advantage of being able to monitor atrial arrhythmic events, but complication rates were higher and additional cost and longer procedure time are usually required than SC ICD. Sixty percent of ICD implantation patients who have are SC ICD Recently, a unique ICD lead with atrial sensing ring capable of monitoring the atrial electrical signals has been developed [Intica 7 VR-T DX ICD (Biotronik., Germany)]. Therefore, turning off the atrial sensing function makes it functionally the same as SC ICD whereas turning on makes it function similar to DC ICD without additional cost and procedure time. Therefore, Detection of AF could be made earlier with VDD ICD versus conventional SC ICD without atrial sensing capability, providing a better chance to improve the prognosis of ICD patients. However, no study exists which shows whether VDD ICD is better for detecting atrial tachyarrhythmia than conventional SC ICD. Therefore, we designed a multicenter prospective randomized study comparing the AF diagnostic efficacy of VDD ICD (with atrial sensing 'ON') against conventional SC ICD. As the second phase, we also plan to compare inappropriate therapy rate according to atrial sensing status of VDD ICD.

Official Title
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A Prospective, Multicenter, Randomized Controlled Trial Comparing Atrial Sensing ON-mode of VDD Implantable Cardioverter Defibrillator(ICD) to Atrial Sensing OFF-mode of VDD ICD in Detecting Atrial Fibrillation(Smart-Control Study)

Conditions
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Implantable Cardioverter Defibrillator, Atrial Fibrillation, Cardiac Event, Cardiac Arrhythmia

Intervention / Treatment
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* Device: Atrial sensing On mode


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age ≥ 19 years indication for ICD implantation according to guidelines atrial fibrillation didn't detect by electrocardiogram or Holter test within the past 1 year from the ICD implantation, and CHA2DS2VASc score ≥1 point in male or ≥ 2 in female Exclusion Criteria: persistent or permanent atrial fibrillation (AF) atrial fibrillation detected by electrocardiogram or Holter test within the past 1 year from the ICD implantation history of the catheter or surgical ablation of AF or taking antiarrhythmic drug scheduled to undergo heart transplant within 1 year life expectancy < 1 year requiring atrial pacing

Ages Eligible for Study
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Minimum Age: 19 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: Screening
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients are randomly assigned as atrial sensing ON or Off mode
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Atrial sensing OFF mode<br>VDD-ICD programmed as atrial sensing Off mode | |
| Active Comparator: Atrial sensing ON mode<br>VDD-ICD programmed as atrial sensing ON mode | Device: Atrial sensing On mode<br>* Single lead VDD-ICD programmed as atrial sensing On mode.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Atrial fibrillation | cardiac implantable electronic device-detected or clinical atrial fibrillation | from enrollment to last follow-up (2 years) | 
| Inappropriate device therapy | inappropriate ATP or shock | from enrollment to last follow-up (2 years) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants with complications associated with atrial fibrillation | thromboembolic events, heart failure | from enrollment to last follow-up (2 years) | 
| Number of Participants with ventricular arrhythmia | cardiac implantable electronic device-detected or clinical ventricular arrhythmia | from enrollment to last follow-up (2 years) | 
| Number of Participants with major adverse composite events | cardiac death, all cuase death, stroke, atrial fibrillation or flutter, ventricular tachyarrhythmia, hospitalization for heart failure | from enrollment to last follow-up (2 years) | 
| atrial lead sensing stability | Atrioventricular synchrony ratio | from enrollment to last follow-up (2 years) |