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Device-based Rate Versus Rhythm Control in Symptomatic Recent-onset Atrial Fibrillation (RACE 9 OBSERVE-AF)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT04612335
Recruitment Status : Recruiting
First Posted : November 2, 2020
Last Update Posted : December 3, 2021
ZonMw: The Netherlands Organisation for Health Research and Development
Dutch Heart Foundation
Netherlands Organisation for Scientific Research
Information provided by (Responsible Party):
Maastricht University Medical Center

Brief Summary:
Continuous heart rhythm monitoring elucidated the recurrent and transient nature of recent-onset atrial fibrillation (AF). The RACE7 ACWAS showed that a wait-and-see approach (WAS) in patients with recent-onset AF (rate control for symptom relief followed by delayed cardioversion if needed <48h) allows spontaneous conversion to sinus rhythm in 69% of patients, obviating active cardioversion. Recurrences within one month were seen in 30% of patients in both groups, i.e. the initially chosen strategy did not affect the recurrence pattern. Considering the latter, it remains unclear whether cardioversion is needed at all, especially since cardioversion strategy does not seem to affect behaviour of the arrhythmia over time. Instead of cardioversion a watchful-waiting rate control strategy may be appropriate as initial strategy. This allows observing the electrical and clinical behavior of arrhythmia, providing a solid basis for comprehensive and effective early rhythm control. This study is a multi-center clinical randomized controlled trial to show non-inferiority of watchful-waiting with rate control versus routine care in terms of prevalence of sinus rhythm at 4 weeks follow-up, using a novel telemonitoring infrastructure to guide rate control during follow-up.

Condition or disease Intervention/treatment Phase
Atrial Fibrillation Other: Rate control Other: Pharmacological or electrical cardioversion Not Applicable

Detailed Description:
Until recently standard of care for patients with recent-onset atrial fibrillation (AF) was early cardioversion. This has just been expanded with a delayed cardioversion approach. However, considering the recurrent and transient nature of AF, cardioversion might not be needed at all and rate control medication might be sufficient to accomplish spontaneous conversion to sinus rhythm. The aim of this trial is to evaluate effectiveness (presence of sinus rhythm) of a watchful-waiting approach, i.e. symptom reduction through rate-control medication and monitoring until spontaneous conversion is achieved compared to routine care, consisting of either early or delayed cardioversion. The trial is a multicentre prospective, randomized, open label, non-inferiority trial comparing the interventional watchful-waiting approach to routine care (control).The primary endpoint (presence of sinus rhythm), will be assessed after 4 weeks. The total follow-up time is 1 year.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 490 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Device-based Rate Versus Rhythm Control Treatment in Patients With Symptomatic Recent-onset Atrial Fibrillation in the Emergency Department (RACE 9 OBSERVE-AF)
Actual Study Start Date : November 16, 2020
Estimated Primary Completion Date : June 2024
Estimated Study Completion Date : June 2025

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: Watchful waiting
the watchful-waiting approach consists of administration of rate control medication to obtain relief of symptoms and a heart rate <110 beats per minute, followed by a telemetric rhythm monitoring period of four weeks to guide rate control therapy.
Other: Rate control
Rate control drugs are administered to obtain symptom relief and a heart rate of <110 bpm, followed by a 4-week telemonitoring period.

Routine care
Routine care consists of the standard treatment for an acute episode of recent-onset symptomatic atrial fibrillation, namely acute or delayed cardioversion, followed by a telemetric rhythm monitoring period of four weeks to guide rate control therapy.
Other: Pharmacological or electrical cardioversion
Pharmacological or electrical cardioversion is performed to achieve restoration of sinus rhythm, either acutely or in a wait-and-see approach, all within 48 hours, and followed by a 4-week telemonitoring period.

Primary Outcome Measures :
  1. Presence of sinus rhythm [ Time Frame: 4 weeks after inclusion ]
    Sinus rhythm documented on a 12-lead ECG

Secondary Outcome Measures :
  1. Implementation of the telemonitoring infrastructure [ Time Frame: 4 weeks ]
    e.g. use of telemonitoring infrastructure during the 4 weeks follow up, accuracy of alert system

  2. MACCE: major cardiovascular mortality and cardiovascular and cerebrovascular events [ Time Frame: 1 year ]
    e.g. hospitalisation for stroke, myocardial infarction

  3. AF recurrences/AF progression [ Time Frame: 4 weeks and 1 year ]
    e.g. number of AF recurrences, progression to persistent AF

  4. Cost-effectiveness [ Time Frame: 1 year ]
    The costs and cost-effectiveness of the new approach will be determined and compared to the costs and cost-effectiveness of routine care.

  5. Questionnaires on quality of life (SF-36) [ Time Frame: 1 year ]
    Questionnaires on quality of life (e.g. SF-36), will be used to assess whether there are differences between the two arms. The SF-36 will be evaluated according to recommendations; scores will be recoded on a scale of 0-100 and averaged. Higher scores indicate better quality of life.

  6. Patient reported experiences [ Time Frame: 1 year ]
    A questionnaire on patient reported experiences with the telemonitoring device will be used to assess whether there are differences between the two arms. There will be both positively orientated, and negatively orientated questionnes which have to be rated on a scale of 1-5.

  7. Rate and rhythm control interventions (number of) [ Time Frame: 4 weeks ]
    Alert- and patient-triggered

  8. Rhythm control interventions [ Time Frame: 1 year ]
    Number of participants with cardioversion, catheter ablation

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • ECG with atrial fibrillation
  • Duration of the current AF episode <36 hours
  • Symptoms due to atrial fibrillation
  • Age > 18 years
  • Able and willing to sign informed consent
  • Able and willing to use telemetric rhythm recorder

Exclusion Criteria:

  • History of persistent AF (episode of AF lasting more than 48 hours and terminated by cardioversion)
  • Deemed unsuitable for participation by attending physician
  • Hemodynamic instability (heart rate >170 bpm, systolic blood pressure <100 mmHg)
  • Acute heart failure
  • Signs of myocardial infarction
  • History of syncope of unexplained origin
  • History of untreated Sick Sinus Syndrome
  • History of untreated Wolff-Parkinson-White syndrome
  • Currently enrolled in another clinical trial

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04612335

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Contact: Rachel MJ van der Velden, MD 31433876885
Contact: Nikki AH Pluymaekers, MD 31433875119

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Maastricht University Medical Center Recruiting
Maastricht, Limburg, Netherlands, 6229AX
Contact: Rachel van der Velden, MD    +31433876885   
Noordwest Ziekenhuisgroep Recruiting
Alkmaar, Noord-Holland, Netherlands, 1815JD
Contact: S Timmer         
Vrije Universiteit Medisch Centrum Recruiting
Amsterdam, Netherlands
Contact: O Kamp         
Rijnstate Recruiting
Arnhem, Netherlands
Contact: M Hemels         
Medisch Spectrum Twente Recruiting
Enschede, Netherlands
Contact: J van Opstal         
Martini Ziekenhuis Recruiting
Groningen, Netherlands
Contact: R Tieleman         
Universitair Medisch Centrum Groningen Recruiting
Groningen, Netherlands
Contact: I van Gelder         
Zuyderland Medisch Centrum Recruiting
Heerlen, Netherlands
Contact: T Lenderink         
Alrijne Ziekenhuis Recruiting
Leiderdorp, Netherlands
Contact: C Kirchhof         
St Antonius Ziekenhuis Recruiting
Nieuwegein, Netherlands
Contact: V van Dijk         
Radboud UMC Recruiting
Nijmegen, Netherlands
Contact: R Beukema         
Antonius Ziekenhuis Recruiting
Sneek, Netherlands
Contact: A Oomen         
St. Elisabeth TweeSteden Ziekenhuis Recruiting
Tilburg, Netherlands
Contact: J Widdershoven         
VieCuri Medical Centre Recruiting
Venlo, Netherlands
Contact: W Heesen         
Sponsors and Collaborators
Maastricht University Medical Center
ZonMw: The Netherlands Organisation for Health Research and Development
Dutch Heart Foundation
Netherlands Organisation for Scientific Research
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Study Chair: Harry JG Crijns, MD, PhD Head of cardiology department, Maastricht University Medical Center
Principal Investigator: Dominik Linz, MD, PhD Head of cardiac electrophysiology, Maastricht University Medical Center
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Responsible Party: Maastricht University Medical Center Identifier: NCT04612335    
Other Study ID Numbers: NL73104.068.20
First Posted: November 2, 2020    Key Record Dates
Last Update Posted: December 3, 2021
Last Verified: December 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: All elements from the CRF matching a future project's CRF may be provided for an aggregated analysis.
Supporting Materials: Study Protocol
Statistical Analysis Plan (SAP)
Informed Consent Form (ICF)
Clinical Study Report (CSR)
Time Frame: Well after publication of main paper
Access Criteria: Please contact principal investigator or study chair.

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Maastricht University Medical Center:
Atrial fibrillation
Cardiac arrhythmia
Electrical cardioversion
Watchful waiting
Additional relevant MeSH terms:
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Atrial Fibrillation
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes