An interventional study of Marshall Plan-Based Ablation Strategy and PV re-isolation only in Atrial Fibrillation (AF), sponsored by Karolinska University Hospital. Not yet recruiting at 1 site in Sweden. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-28.
Sponsored by Karolinska University Hospital · Not applicable, Interventional, and Treatment
This clinical trial will assess the efficacy and safety of a Marshall plan-based ablation strategy without ethanol infusion into the vein of Marshall in patients with persistent atrial fibrillation undergoing repeat ablation with a dual-energy lattice-tip catheter. Eligible participants will be randomized to receive either pulmonary vein re-isolation alone or pulmonary vein re-isolation plus the Marshall plan-based strategy. Patients who are found to have all pulmonary veins already isolated at the time of the procedure, or who are not suitable candidates for the Marshall plan-based approach, will be included in a separate observational cohort.
Pulmonary vein (PV) re-isolation remains the standard ablation strategy for patients with persistent atrial fibrillation undergoing repeat ablation procedures. However, recurrence after PV re-isolation remains common, and the optimal adjunctive ablation strategy during redo procedures has not been established. The introduction of dual-energy lattice-tip catheters enables the creation of durable linear lesions beyond PV isolation while avoiding the need for ethanol infusion into the vein of Marshall. Although the Marshall-plan strategy has demonstrated favorable results in patients undergoing first-time ablation, randomized data evaluating this approach during repeat ablation procedures are lacking.
This study aims to evaluate the efficacy and safety of a Marshall plan-based ablation strategy without ethanol infusion into the vein of Marshall, in addition to pulmonary vein re-isolation, compared with pulmonary vein re-isolation alone in patients with persistent atrial fibrillation undergoing repeat ablation using a dual-energy lattice-tip catheter. Eligible participants will be randomized to one of the two treatment strategies. Patients whose pulmonary veins are found to be already isolated at the time of the procedure, or for whom the Marshall plan-based approach is not feasible, will be included in a separate observational cohort.
4,009 studies on the registry are indexed under Atrial Fibrillation; 961 are open to participants now.
This study's planned enrollment of 234 is above the median of 150 across 2,476 interventional studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →Karolinska University Hospital is the lead sponsor of 279 studies on the registry; 55 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will undergo pulmonary vein re-isolation combined with a Marshall plan-based ablation strategy using a dual-energy lattice-tip catheter.
Procedure: Marshall Plan-Based Ablation Strategy
Participants will undergo pulmonary vein re-isolation using a dual-energy lattice-tip catheter.
Procedure: PV re-isolation only
Patients with already isolated pulmonary veins or those unsuitable for a Marshall plan-based strategy will be included in this observational cohort and will not undergo randomization.
Procedure: Additional Left Atrial Ablation
Pulmonary vein re-isolation plus posterior mitral isthmus, roof, and cavotricuspid isthmus linear ablation using a dual-energy lattice-tip catheter without ethanol infusion into the vein of Marshall.
Pulmonary vein re-isolation only using a dual-energy lattice-tip catheter.
Additional left atrial ablation performed according to the scar distribution
Between-group difference in atrial-arrhythmia burden
Between-group difference in atrial-arrhythmia burden, defined as the percentage of analyzable ILR time spent in atrial arrhythmia, measured during off-AAD intervals from the end of the 8-week blanking period through 12 months and before any crossover ablation, comparing PV re-isolation plus Marshall-plan strategy versus PV re-isolation alone.
Time frame: From the end of the 8-week blanking period through 12 months and before any crossover ablation
Number of Participants with Freedom from Atrial Arrhythmia after 1 Ablation Procedure without Antiarrhythmic Drugs (AAD)
1\. Freedom from AF/AT/AFL ≥30 s at 12 months (after 8-week blanking period), centrally adjudicated
Time frame: From the end of the 8-week blanking period through 12 months and before any crossover ablation
Arrhythmia burden during off-AAD follow-up time and before any crossover ablation
Arrhythmia burden during off-AAD follow-up time and before any crossover ablation, with additional sensitivity analyses accounting for DC cardioversion and repeat ablation.
Time frame: From the end of the 8-week blanking period through 12 months and before any crossover ablation
Arrhythmia burden between groups in patients on AAD
Time frame: From the end of the 8-week blanking period through 12 months and before any crossover ablation
Between-group difference in atrial-arrhythmia burden, percent of analyzable time in AF/AT/AFL by ILR measured irrespective of the AAD use
Time frame: From the end of the blanking period (week 8) through 12 months, comparing PV re-isolation + Marshall-plan vs PV re-isolation only.
Differences in arrhythmia burden without blanking period.
Time frame: Through 12 months, comparing PV re-isolation + Marshall-plan vs PV re-isolation only.
Total procedure time
Time frame: During the index procedure
Total fluoroscopy time
Time frame: During the index procedure
Freedom from DC cardioverted atrial arrhythmia
Time frame: At 6 and 12 months
Freedom from atrial fibrillation
Time frame: At 6 and 12 months
Number of DC-cardioverted atrial arrhythmia
Time frame: From the end of the blanking period (week 8) through 12 months, comparing PV re-isolation + Marshall-plan vs PV re-isolation only.
Burden analysis adjusted for the number of post-blanking DC cardioversions
Time frame: From the end of the blanking period (week 8) through 12 months, comparing PV re-isolation + Marshall-plan vs PV re-isolation only.
Sensitivity analysis excluding ILR time after any repeat ablation.
Time frame: Up to 12 months after the index procedure
Freedom from any repeat ablation procedure
Time frame: Through 12 months
Composite adverse events
Time frame: From the index procedure through 12 months of follow-up
The primary safety endpoint would be any adverse event related to ablation
Time frame: From the index procedure through 12 months of follow-up
Differences in AF and atrial tachycardia burden between the two randomization groups (ILR) and possible predictors of this difference
Time frame: From the index procedure through 12 months of follow-up
LA size, morphology, and function from echocardiographic and CT imaging data
Time frame: At the index procedure
HRQoL measured with ASTA
Time frame: 12 months after ablation
Correlation between arrhythmia burden and HRQoL/symptoms
Time frame: At 12 months after ablation
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Karolinska University Hospital →