Detection of Atrial Fibrillation After Cardiac Surgery (SEARCH-AF)

Post-Surgical Enhanced Monitoring for Cardiac Arrhythmias and Atrial Fibrillation (SEARCH-AF): A Randomized Controlled Trial

The aim of the SEARCH-AF trial is to evaluate a novel diagnostic tool for detecting post-operative atrial fibrillation or flutter (POAF/AFL) in cardiac surgical subjects during the early, sub-acute post-operative period. The population includes cardiac surgical subjects who have either developed or are at risk for developing new onset POAF/AFL and who are at risk for stroke, as determined by their CHA2DS2-VASC (congestive heart failure, hypertension, age ≥75 years (2 points), diabetes mellitus, previous stroke/transient ischemic attack (TIA) (2 points), vascular disease, age 65-74 years, sex class (female)) score. These subjects must not have had a history of AF/AFL before cardiac surgery.

The intervention group will undergo up to 30 days of continuous cardiac rhythm monitoring with an adhesive, patch-based monitor (Medtronic SEEQ™ mobile cardiac telemetry system or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device). The control group will receive usual care, which does not involve planned cardiac rhythm testing within the first 30 days after study randomization. The primary outcome is documentation of sustained atrial fibrillation or flutter within the first 30 days after randomization. In addition, subjects in both groups will undergo 14 days of continuous cardiac rhythm monitoring with the Medtronic SEEQ™ mobile cardiac telemetry system or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device at 6±1 months after their index cardiac surgery.

Study Overview

• Status: Terminated
• Conditions: Atrial Fibrillation; Arrhythmias, Cardiac; Atrial Flutter; C.Surgical Procedure; Cardiac
• Intervention / Treatment: Device: Medtronic SEEQ™ mobile cardiac telemetry system; Device: CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device; Other: Usual Care

Detailed Description

The aim of the SEARCH-AF trial is to evaluate a novel diagnostic tool for detecting post-operative atrial fibrillation or flutter (POAF/AFL) in cardiac surgical subjects during the early, sub-acute post-operative period. Its primary objective is to test whether enhanced cardiac rhythm monitoring with an adhesive, continuous monitor results in higher rates of atrial fibrillation or flutter (AF/AFL) detection at 30 days after randomization for post-cardiac surgical subjects who are at risk for developing post-operative atrial arrhythmias, when compared to usual care.

The study design is an open-label, two-arm randomized controlled trial (RCT) comparing a strategy of enhanced cardiac rhythm monitoring vs. usual care in 396 post-cardiac surgical subjects who are at risk for developing POAF/AFL.

The primary endpoint is the proportion of subjects with a cumulative AF/AFL burden of ≥6 minutes or documentation of AF/AFL by a 12-lead ECG within 30 days after randomization. Clinical endpoints will be adjudicated by an independent committee of physicians.

The study population involves post-cardiac surgical subjects at high risk of stroke, defined as having a CHA2DS2-VASC score of ≥4 or CHA2DS2-VASC of ≥2 with additional risk factors for developing POAF/AFL. These subjects must not have a history of AF/AFL pre-operatively.

Subjects who meet inclusion criteria will be randomized in a 1:1 ratio to one of the following 2 arms: (i) Enhanced cardiac rhythm monitoring (intervention group) or (ii) Usual care (control group). Subjects in the intervention group will receive up to 30 days of continuous cardiac rhythm monitoring with the Medtronic SEEQ™ mobile cardiac telemetry system or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device. Monitoring will begin on the day of randomization. Subjects in the usual care group will not undergo protocol-mandated cardiac rhythm monitoring during the first 30 days after randomization.

All subjects will have a follow-up visit at 31-90 days after hospital discharge and at 6±1 months after surgery. At 6±1 months, all subjects will undergo 14 days of continuous cardiac rhythm monitoring with the SEEQ™ mobile cardiac telemetry system or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device. A telephone follow-up will be performed for all subjects at 9±1 months after surgery.

• Study Type: Interventional
• Enrollment (Actual): 336
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Calgary, Canada, T2N 4N1
    • Foothills Medical Centre
  • Edmonton, Canada, T6G 2B7
    • Mazankowski Alberta Heart Institute
  • Manitoba
    • Winnipeg, Manitoba, Canada, R2H 2A6
      • St. Boniface General Hospital
  • New Brunswick
    • Saint John, New Brunswick, Canada, E2L 4L2
      • Saint John Regional Hospital
  • Ontario
    • Kingston, Ontario, Canada, K7L 2V7
      • Kingston General Hospital
    • Newmarket, Ontario, Canada, L3Y 3S9
      • Southlake Regional Health Centre
    • Ottawa, Ontario, Canada, K1Y 4E9
      • University of Ottawa Heart Institute
    • Toronto, Ontario, Canada, M5G 2C4
      • University Health Network
    • Toronto, Ontario, Canada, M5B1W8
      • St. Michael's Hospital
  • Quebec
    • Quebec City, Quebec, Canada, G1V 4G2
      • Universite Laval

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Male or female age ≥18 years.
2. Isolated CABG or valve replacement/repair +/- CABG performed at the index surgical procedure.

3. At elevated risk of stroke and for having POAF/AFL, defined as having a CHA2DS2-VASC (congestive heart failure, hypertension, age ≥75 years (2 points), diabetes mellitus, previous stroke/transient ischemic attack (TIA) (2 points), vascular disease, age 65-74 years, sex class (female)) score of ≥4 or ≥2 with at least 1 of the following risk factors for developing POAF/AFL:

   (i) Chronic obstructive pulmonary disease; (ii) Sleep apnea; (iii) Impaired renal function (defined as creatinine clearance <60 ml/min/1.73m2 or <60 ml/min); (iv) Echocardiographic evidence of at least mild left atrial enlargement (defined as ≥41 mm on M-mode, ≥59 ml or ≥29 mL/m2 on biplane volume assessment from an echocardiogram performed within 12 months of study enrollment); (v) Elevated body mass index (defined as BMI ≥30); (vi) Combined surgery (CABG + valve repair/replacement).

4. Able to provide written informed consent.

Exclusion Criteria:

1. Atrial fibrillation or flutter at the time of randomization.
2. Known previous history of AF/AFL, diagnosed pre-operatively (note: documentation of a history of AF/AFL without accompanying rhythm proof will suffice).
3. Documentation of continuous AF/AFL for ≥24 hours during the in-hospital stay for the index cardiac surgery.
4. Subjects who, at the discretion of the treating cardiac surgery team, would be treated and discharged with oral anticoagulation due to POAF/AFL.
5. Mechanical valve replacement.
6. Current or anticipated treatment with oral anticoagulation for indications other than AF/AFL.
7. Hospitalization for ≥10 days (for the index cardiac surgery, with day #0 being the day of surgery).
8. Planned discharge from hospital with a type IC or III anti-arrhythmic drug.
9. Having received >5 grams of IV and/or oral amiodarone during hospitalization for the index cardiac surgical procedure.
10. Women of childbearing potential (WOCBP).
11. History of percutaneous or surgical left atrial ablation for AF.
12. Presence of a cardiac implantable electronic device with a functioning atrial lead (pacemaker, implantable cardioverter defibrillator, or cardiac resynchronization device).
13. Presence of an implantable loop recorder.
14. History of left atrial appendage ligation, removal, or occlusion.
15. Subjects with known allergies or hypersensitivities to adhesives or hydrogel.
16. Inability to provide written informed consent.
17. Current or anticipated participation in another randomized controlled trial in which the interventional drug or device is known to affect the incidence of the primary or secondary outcomes of this study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Enhanced cardiac rhythm monitoring; Subjects in this group will receive up to 30 days of continuous cardiac rhythm monitoring with an adhesive monitor. Cardiac rhythm monitoring will begin on the day of randomization. The device that will be used is the Medtronic SEEQ™ mobile cardiac telemetry system or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device. At 6+/-1 months, subjects randomized to the intervention group will undergo 14 days of continuous cardiac rhythm monitoring with the SEEQ™ device or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device.	Device: Medtronic SEEQ™ mobile cardiac telemetry system; The SEEQ™ system consists of a wearable sensor which is a single-lead, low-profile, peel-and-stick device applied over the anterior left chest wall of the subject. The wearable patch is designed for one-time use only and cannot be re-applied if removed. Each sensor provides up to 7.5 days of monitoring. Subjects randomized to the intervention group will undergo 30 days of continuous cardiac rhythm monitoring with the SEEQ™ device at the time of randomization. At 6+/-1 months, subjects randomized to the intervention group will undergo 14 days of continuous cardiac rhythm monitoring with the SEEQ™ device.; Device: CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device; The CardioSTAT device is a wearable adhesive cardiac rhythm monitoring system which is low-profile, water-resistant, and is adhered onto the skin surface with 2 electrodes. This wearable adhesive device is designed for one-time use only. Each CardioSTAT device will provide 14 days of cardiac rhythm monitoring. For subjects randomized to the intervention group who will be monitored by the CardioSTAT device, they will receive 28 days of continuous cardiac rhythm monitoring.
Active Comparator: Usual care; Subjects randomized to the usual care arm will be discharged from hospital without protocol-mandated continuous cardiac rhythm monitoring. Within the first 30 days after randomization, no protocol-mandated cardiac rhythm assessment will be arranged. At 6+/-1 months, subjects randomized to the usual care group will undergo 14 days of continuous cardiac rhythm monitoring with the SEEQ™ device or the CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device.	Other: Usual Care; For subjects randomized to the usual care group, no protocol-mandated cardiac rhythm monitoring will be performed. However, subjects in the control group may undergo rhythm monitoring during the study period if their treating physicians deem that there is a clinical indication to so do. At 6+/-1 months, subjects randomized to the usual care group will undergo 14 days of continuous cardiac rhythm monitoring with the SEEQ™ device or the CardioSTAT (Icentia. Inc) cardiac rhythm monitoring device.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with a cumulative atrial fibrillation/flutter (AF/AFL) duration of ≥6 minutes or documentation of AF/AFL by a 12-lead electrocardiogram	The primary endpoint of this trial is documentation of sustained AF/AFL, defined as a cumulative AF/AFL duration of ≥6 minutes or documentation of AF/AFL by a 12-lead ECG within 30 days after randomization. Clinical endpoints will be adjudicated by an independent clinical events committee.	Within 30 days of randomization.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with atrial fibrillation or flutter lasting for ≥24 hours.	This outcome will be measured by a continuous cardiac modality (e.g. Holter, Event monitor, SEEQ™ mobile cardiac telemetry system, CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device).	(i) Within 30 days of randomization and (ii) Between day 31 and the last follow-up date.
Duration of cumulative atrial fibrillation or flutter burden amongst participants.	This outcome will be measured by a continuous cardiac modality (e.g. Holter, Event monitor, SEEQ™ mobile cardiac telemetry system, CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device).	Between day 31 of randomization and the last follow-up date.
Number of participants who are prescribed with oral anticoagulation for atrial fibrillation or flutter-related stroke prevention.	This outcome will be collected during study follow-up visits.	(i) Within the first 45 days after discharge from cardiac surgery; (ii) Between day 46 and the last follow-up date.
Number of days during which the adhesive Medtronic SEEQ™ or CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device was worn by participants.	This outcome will be collected during study follow-up visits.	(i) Within 30 days after randomization (intervention group only); (ii) Between day 31 and the last follow-up date (all subjects).
Number of participants who prematurely remove the adhesive Medtronic SEEQ™ or CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device.	This outcome will be collected during study follow-up visits.	(i) Within 30 days after randomization (intervention group only); (ii) Between day 31 and the last follow-up date (all subjects).
Number of participants with adverse events related to the use of the Medtronic SEEQ™ or CardioSTAT (Icentia Inc.) cardiac rhythm monitoring device.	This outcome will be collected during study follow-up visits.	(i) Within 30 days after randomization (intervention group only); (ii) Between day 31 and the last follow-up date (all subjects).
Number of participants who undergo non-protocol mandated Holter monitoring and/or event recorders.	This outcome will be collected during study follow-up visits.	(i) Within 30 days after randomization; (ii) Between day 31 and the last follow-up date.
Hospitalization or emergency room visits.	This outcome will be collected during study follow-up visits.	Within the first 45 days after hospital discharge from index cardiac surgery.
Major adverse cardiac outcomes.	All-cause death, myocardial infarction, ischemic stroke, non-CNS systemic embolism.	(i) Within the first 45 days after hospital discharge from index cardiac surgery; (ii) Between day 46 and the last follow-up date.
Number of participants with bleeding events.	Major bleeding.	(i) Within the first 45 days after hospital discharge from index cardiac surgery; (ii) Between day 46 and the last follow-up date.

Collaborators and Investigators

• Sponsor: Unity Health Toronto
• Investigators: Principal Investigator: Subodh Verma, MD, PhD, Unity Health Toronto; Principal Investigator: Andrew CT Ha, MD, University Health Network, Toronto; Principal Investigator: Atul Verma, MD, St. Michael's Hospital and Southlake Regional Health Centre

Publications and helpful links

General Publications

• Ha ACT, Verma S, Mazer CD, Quan A, Yanagawa B, Latter DA, Yau TM, Jacques F, Brown CD, Singal RK, Yamashita MH, Saha T, Teoh KH, Lam BK, Deyell MW, Wilson M, Hibino M, Cheung CC, Kosmopoulos A, Garg V, Brodutch S, Teoh H, Zuo F, Thorpe KE, Jüni P, Bhatt DL, Verma A; SEARCH AF CardioLink-1 Investigators. Effect of Continuous Electrocardiogram Monitoring on Detection of Undiagnosed Atrial Fibrillation After Hospitalization for Cardiac Surgery: A Randomized Clinical Trial. JAMA Netw Open. 2021 Aug 2;4(8):e2121867. doi: 10.1001/jamanetworkopen.2021.21867.
• Yanagawa B, Ad N, Gaudino MF. Commentary: Postoperative atrial fibrillation can last years? Oh snap! J Thorac Cardiovasc Surg. 2020 Apr;159(4):1417-1418. doi: 10.1016/j.jtcvs.2019.04.028. Epub 2019 Apr 24. No abstract available.

Study record dates

Study Major Dates

• Study Start (Actual): February 24, 2017
• Primary Completion (Actual): August 31, 2020
• Study Completion (Actual): September 11, 2020

Study Registration Dates

• First Submitted: May 2, 2016
• First Submitted That Met QC Criteria: June 2, 2016
• First Posted (Estimate): June 8, 2016

Study Record Updates

• Last Update Posted (Actual): June 18, 2021
• Last Update Submitted That Met QC Criteria: June 14, 2021
• Last Verified: June 1, 2021

More Information

Terms related to this study

• Keywords: Cardiac surgery; Oral anticoagulation; Stroke prevention; Atrial fibrillation/flutter; Postoperative atrial arrhythmia; Cardiac rhythm monitoring
• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Atrial Fibrillation; Arrhythmias, Cardiac; Atrial Flutter
• Other Study ID Numbers: SEARCH-AF-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No