Atrial FibrillationAFFELECTNCT04267159
Acute Atrial Fibrillation and Flutter Treated Electively
A study testing Acute cardioversion and Delayed cardioversion in people with Atrial Fibrillation and Atrial Flutter, run by Tampere University at 4 sites in Finland.
Trial summary
The AFFELECT -study compares two types of treatment modalities for acute atrial fibrillation or flutter for patients in whom rhythm control is desirable. The main purpose is to observe if these arrhythmias can be safely treated electively (within 5-9 days). All patients are recruited in the emergency department. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Atrial Fibrillation, Atrial Flutter
- What is being tested?
- Acute cardioversion and Delayed cardioversion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 500 participants
- Where
- 4 sitesFinland
- Study dates
- 10 Feb 2020to Jun 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Patients presenting with acute (<48hours) atrial fibrillation or atrial flutter to ER
- Planned acute rhythm control for the arrhythmia by the attending physician in ER
- Good perceived health as assessed by attending physician in ER
- Resting heart rate 110bpm or lower before or after adequate rate control therapy
Who cannot join
- Haemodynamically stable (mean arterial pressure above 60mmHg)
- Need for acute restoration of sinus rhythm due to some other somatic cause
- No other major complicating acute illness (e.g. decompensated HF or acute MI)
- Anticoagulation not safe
- Mechanical heart valve or mitral stenosis
- The need for prolonged (>24h) hospitalization due to any cause
- Exceptionally high risk for thromboembolic events (e.g. history of thromboembolic stroke regardless of adequate anticoagulation)
- Transesophageal echocardiography contraindicated
Trial locations and contacts
4 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Tero Penttilä, MD, PhD contact
Finland4 sites, 4 recruiting
- Recruiting
Kanta-Häme Central Hospital
Hämeenlinna, Kanta-Häme
Ari Palomäki, MD, PhD
- Recruiting
Central Finland Central Hospital
Jyväskylä, Central Finland
Tuomo Kyrönlahti, MD, tuomo.kyronlahti@ksshp.fi
- Not yet recruiting
Päijät-Häme Central Hospital
Lahti, Paijat-Hame Region
Tuomo Nieminen, MD, PhD, tuomo.nieminen@phshp.fi
- Recruiting
Tampere University Hospital
Tampere, Pirkanmaa, 03220
Jussi A Hernesniemi, MD, PhD, 41732 2932 ext. +358, jussi.hernesniemi@sydansairaala.fi
About this study
Official title: Acute Atrial Fibrillation and Flutter Treated Electively - A Randomized Controlled Clinical Trial on the Safety of Elective Management of Acute Atrial Fibrillation and Flutter
The AFFELECT -study compares two types of treatment modalities for acute atrial fibrillation or flutter for patients in whom rhythm control is desirable. The main purpose is to observe if these arrhythmias can be safely treated electively (within 5-9 days).
All patients are recruited in the emergency department. Patients must be in good clinical condition so that they can be discharged regardless to which treatment modality is randomly selected to them. Patients randomized to conventional care are treated conventionally which means acute rhythm control is applied by electrical or medical cardioversion in the emergency department (within 48 hours of onset of the arrhythmia). Patients randomized to elective care are discharged immediately after adequate temporary rhythm control is assured.
Read more
All patients will visit a cardiologist out-patient clinic at approximately one week after the emergency room visit. Patients randomized to elective treatment and still in atrial fibrillation or in atrial flutter will be restored to sinus rhythm by electrical or medical cardioversion at the out-patient clinic. Cardiovascular status and treatment options are evaluated for all patients.
Anticoagulation is managed according existing guidelines for all patients. Due to possibility of delayed cardioversion in the interventional group (elective care group), all patients receive anticoagulation before the out-patient clinic despite their thromboembolic risk. All patients who have not received adequate anticoagulation for three weeks prior to the delayed cardioversion will undergo a transesophageal cardiac ultrasound to ensure they are not in excess risk for thromboembolic events. Patients randomized to elective treatment have the possibility to opt-out and undergo acute cardioversion if their symptoms are unmanageable during the first week before the out-patient clinical.
All patients are monitored for their symptoms by a standardized quality-of-life questionnaire and for possibly required acute medical interventions during the first week and one month after the out-patient clinic. After one month, all patients undergo an electrocardiography (ECG) to ensure the maintenance of normal rhythm in both treatment groups. After the months follow-up all patients are subsequently monitored for a maximum of five years for need of medical interventions due to atrial fibrillation of atrial flutter. New antiarrhythmics such as flecainide are not prescribed during the first month.
- Conditions
- Atrial Fibrillation, Atrial Flutter
- Being tested
- Acute cardioversion, Delayed cardioversion
- Medical subject headings
- Atrial Fibrillation, Atrial Flutter
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Acute cardioversionOther
Acute restoration of sinus rhythm by medical or electrical cardioversion in the emergency department
Delayed cardioversionOther
Delayed restoration of sinus rhythm by medical or electrical cardioversion in the out-patient clinic
| Study group | Role | What they receive |
|---|---|---|
| Conventional treatment by acute cardioversion | Active comparator | Participants in the conventional treatment arm will be returned to sinus rhythm in the emergency department within 48 hours of symptom onset unless they convert to sinus rhythm spontaneously. Receives: Other: Acute cardioversion |
| Elective treatment by delayed cardioversion | Experimental | Participants in the elective treatment arm will be returned to sinus rhythm in an out-patient clinic approximately one week after randomizatio unless they convert to sinus rhythm spontaneously. Receives: Other: Delayed cardioversion |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sinus Rhythm
Prevalence of sinus rhythm in the treatment arms measured by electrocardiography
Measured: One month after preplanned out-patient clinic visit
Secondary outcomes (7)
Number of cardioversions after emergency department
The number of performed cardioversions (electrical or medical)
Measured: First week after randomization and before the preplanned out-patient clinic
Number of cardioversions after out-patient clinic
The number of performed cardioversions (electrical or medical)
Measured: One month after out-patient clinic
Overall number of cardioversions
The number of performed cardioversions (electrical or medical)
Measured: From randomization to the end of first month follow-up after out-patient clinic visit
Drop-out from delayed cardioversion group
The number of subjects needing unplanned cardioversion before preplanned out-patient clinic visit (four days or earlier after randomization) due to medical reasons or due to subjectively perceived unbearable symptoms (EHRA III or IV).
Measured: Four days or earlier after randomization to elective (delayed) treatment group
Rehospitalization due to cardiovascular causes
Rehospitalization due to any cardiovascular cause
Measured: One week before and one month after out-patient clinic visit
Immediate quality of life
Quality of life as assessed by questionnaires depicting quality of life (AFEQT)
Measured: First week after randomization and before the preplanned out-patient clinic
Quality of life after out-patient clinic
Quality of life as assessed by questionnaires depicting quality of life (AFEQT)
Measured: One month after out-patient clinic
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Feb 2020
- Study start10 Feb 2020
- Primary completionJun 2027 (estimated)
- Study completionJun 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Atrial FibrillationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- The AFFECT trial is a randomized clinical trial with a non-inferioirity setting studying the applicability of delayed rhythm control in the management of acute paroxysmal or persistent atrial fibrillation or flutter. Patients are randomized to two treatment protocols in 2:3 ratio. For every two patients randomized to conventional treatment, three patients are randomized to experimental treatment. The randomization ratio is designed to allow for maximally one third of the patients in the experimental treatment group to drop-out without compromising the power of the study. Overall five hundred patients are required to show non-inferiority with a one-sided alpha value 0.025 and 90% power expecting a maximal drop out rate of 33% (n=100) from the experimental treatment arm.
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 500 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Tampere University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Jussi Hernesniemi, Tampere University
- Investigators
- Jussi A Hernesniemi, MD, PhD, Principal investigator, TAYS Heart Hospital and Tampere University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04267159
- Sponsor's protocol ID
- ETL R19133
- Acronym
- AFFELECT
- Status last verified
- May 2026
- First submitted
- 10 Feb 2020
- Last updated
- 22 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: IPD can be shared only upon reasonable request after full anonymization by the discretion of the study review board.
Publications
Rankinen J, Lyytikainen LP, Jarventie J, Hautamaki M, Numminen A, Hurskainen M, Rantanen M, Muuronen A, Tynkkynen J, Hernesniemi J. Acute atrial fibrillation and flutter treated electively: rationale and design of the randomized controlled AFFELECT trial. Eur Heart J Open. 2026 Apr 13;6(2):oeag060. doi: 10.1093/ehjopen/oeag060. eCollection 2026 Mar.
PubMed 42064618
Study at a glance
From the registry record, last updated by the sponsor on 22 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Acute Atrial Fibrillation and Flutter Treated Electively - A Randomized Controlled Clinical Trial on the Safety of Elective Management of Acute Atrial Fibrillation and Flutter
- ClinicalTrials.gov ID
- NCT04267159
- Acronym / sponsor ID
- AFFELECT / ETL R19133
- Conditions
- Atrial Fibrillation, Atrial Flutter
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 500 participants (estimated)
- Lead sponsor
- Tampere UniversityUniversity, hospital or other
- Study start
- 10 Feb 2020 (actual)
- Primary completion
- Jun 2027 (estimated)
- Study completion
- Jun 2029 (estimated)
- First posted
- 12 Feb 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The AFFELECT -study compares two types of treatment modalities for acute atrial fibrillation or flutter for patients in whom rhythm control is desirable. The main purpose is to observe if these arrhythmias can be safely treated electively (within 5-9 days).
All patients are recruited in the emergency department. Patients must be in good clinical condition so that they can be discharged regardless to which treatment modality is randomly selected to them. Patients randomized to conventional care are treated conventionally which means acute rhythm control is applied by electrical or medical cardioversion in the emergency department (within 48 hours of onset of the arrhythmia). Patients randomized to elective care are discharged immediately after adequate temporary rhythm control is assured.
All patients will visit a cardiologist out-patient clinic at approximately one week after the emergency room visit. Patients randomized to elective treatment and still in atrial fibrillation or in atrial flutter will be restored to sinus rhythm by electrical or medical cardioversion at the out-patient clinic. Cardiovascular status and treatment options are evaluated for all patients.
Anticoagulation is managed according existing guidelines for all patients. Due to possibility of delayed cardioversion in the interventional group (elective care group), all patients receive anticoagulation before the out-patient clinic despite their thromboembolic risk. All patients who have not received adequate anticoagulation for three weeks prior to the delayed cardioversion will undergo a transesophageal cardiac ultrasound to ensure they are not in excess risk for thromboembolic events. Patients randomized to elective treatment have the possibility to opt-out and undergo acute cardioversion if their symptoms are unmanageable during the first week before the out-patient clinical.
All patients are monitored for their symptoms by a standardized quality-of-life questionnaire and for possibly required acute medical interventions during the first week and one month after the out-patient clinic. After one month, all patients undergo an electrocardiography (ECG) to ensure the maintenance of normal rhythm in both treatment groups. After the months follow-up all patients are subsequently monitored for a maximum of five years for need of medical interventions due to atrial fibrillation of atrial flutter. New antiarrhythmics such as flecainide are not prescribed during the first month.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
- Model description
- The AFFECT trial is a randomized clinical trial with a non-inferioirity setting studying the applicability of delayed rhythm control in the management of acute paroxysmal or persistent atrial fibrillation or flutter. Patients are randomized to two treatment protocols in 2:3 ratio. For every two patients randomized to conventional treatment, three patients are randomized to experimental treatment. The randomization ratio is designed to allow for maximally one third of the patients in the experimental treatment group to drop-out without compromising the power of the study. Overall five hundred patients are required to show non-inferiority with a one-sided alpha value 0.025 and 90% power expecting a maximal drop out rate of 33% (n=100) from the experimental treatment arm.
| Arm | Type | Receives |
|---|---|---|
| Conventional treatment by acute cardioversion | Active comparator | Other: Acute cardioversionParticipants in the conventional treatment arm will be returned to sinus rhythm in the emergency department within 48 hours of symptom onset unless they convert to sinus rhythm spontaneously. |
| Elective treatment by delayed cardioversion | Experimental | Other: Delayed cardioversionParticipants in the elective treatment arm will be returned to sinus rhythm in an out-patient clinic approximately one week after randomizatio unless they convert to sinus rhythm spontaneously. |
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (4 listed)
- Patients presenting with acute (<48hours) atrial fibrillation or atrial flutter to ER
- Planned acute rhythm control for the arrhythmia by the attending physician in ER
- Good perceived health as assessed by attending physician in ER
- Resting heart rate 110bpm or lower before or after adequate rate control therapy
Key exclusion criteria (8 listed)
- Haemodynamically stable (mean arterial pressure above 60mmHg)
- Need for acute restoration of sinus rhythm due to some other somatic cause
- No other major complicating acute illness (e.g. decompensated HF or acute MI)
- Anticoagulation not safe
- Mechanical heart valve or mitral stenosis
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Acute cardioversionAcute restoration of sinus rhythm by medical or electrical cardioversion in the emergency department | Other | Conventional treatment by acute cardioversion |
| Delayed cardioversionDelayed restoration of sinus rhythm by medical or electrical cardioversion in the out-patient clinic | Other | Elective treatment by delayed cardioversion |
Primary outcome
Sinus Rhythm
Time frame: One month after preplanned out-patient clinic visit
Prevalence of sinus rhythm in the treatment arms measured by electrocardiography
7 secondary outcomes
Number of cardioversions after emergency department
Time frame: First week after randomization and before the preplanned out-patient clinic
Number of cardioversions after out-patient clinic
Time frame: One month after out-patient clinic
Overall number of cardioversions
Time frame: From randomization to the end of first month follow-up after out-patient clinic visit
Drop-out from delayed cardioversion group
Time frame: Four days or earlier after randomization to elective (delayed) treatment group
Rehospitalization due to cardiovascular causes
Time frame: One week before and one month after out-patient clinic visit
Immediate quality of life
Time frame: First week after randomization and before the preplanned out-patient clinic
Quality of life after out-patient clinic
Time frame: One month after out-patient clinic
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 May 2026.
- Background: PubMed 42064618Rankinen J, Lyytikainen LP, Jarventie J, Hautamaki M, Numminen A, Hurskainen M, Rantanen M, Muuronen A, Tynkkynen J, Hernesniemi J. Acute atrial fibrillation and flutter treated electively: rationale and design of the randomized controlled AFFELECT trial. Eur Heart J Open. 2026 Apr 13;6(2):oeag060. doi: 10.1093/ehjopen/oeag060. eCollection 2026 Mar.
- Individual participant dataSharing planned: No. IPD can be shared only upon reasonable request after full anonymization by the discretion of the study review board.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Tero Penttilä, MD, PhD contact
Jussi A Hernesniemi, MD, PhD principal investigator
TAYS Heart Hospital and Tampere University
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Acute cardioversion and Delayed cardioversion in people with Atrial Fibrillation and Atrial Flutter, run by Tampere University at 4 sites in Finland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in Finland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Jussi A Hernesniemi, MD, PhD (31164254 ext. +358, jussi.hernesniemi@sydansairaala.fi), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Sinus Rhythm (time frame: One month after preplanned out-patient clinic visit). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04267159, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 May 2026.