An interventional study of Radiofrequency ablation of CTI and Cryoballoon PVI in Atrial Flutter Typical, sponsored by Liverpool Heart and Chest Hospital NHS Foundation Trust. Completed at 10 sites in 2 countries. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2023-11-13.
Sponsored by Liverpool Heart and Chest Hospital NHS Foundation Trust · Not applicable, Interventional, and Treatment
Current guidelines recommend radiofrequency catheter ablation of the cavotricuspid isthmus as treatment for symptomatic/drug-refractory atrial flutter, in spite of the fact that recurrences of flutter and incidence of post-ablation atrial fibrillation are common.
In this study, the investigators assess the hypothesis that the use of cryoballoon Pulmonary Vein Isolation ('novel' treatment) to achieve the electrical disconnection between the pulmonary veins and the heart will lead to higher rates of freedom from abnormal heart rhythms (atrial flutter, atrial fibrillation, or atrial tachycardia) and more improved quality of life than treatment using heat energy (radiofrequency ablation) directed at the cavotricuspid isthmus ('conventional treatment').
Atrial flutter and atrial fibrillation are believed to share the same initiating triggers in the form of pulmonary vein ectopy. Cavo-tricuspid isthmus-dependent atrial flutter almost always results from short bursts of antecedent atrial fibrillation. Radiofrequency (RF) ablation of the cavo-tricuspid isthmus (CTI) is the current accepted first-line treatment for atrial flutter, although post-ablation atrial fibrillation commonly occurs, even in the absence of pre-existing atrial fibrillation.
Cryoballoon Pulmonary Vein Isolation (PVI) has become an established treatment for atrial fibrillation. In patients with both atrial flutter and fibrillation, PVI alone has been shown to control both types of atrial arrhythmia, with no benefit derived from supplemental RF CTI ablation.
This study aims to demonstrate that standalone cryoballoon PVI for typical atrial flutter without RF CTI ablation will lead to a significant difference in preventing recurrence of atrial arrhythmia compared to radiofrequency ablation of the CTI, and should be offered as first-line therapy.
223 studies on the registry are indexed under Atrial Flutter; 51 are open to participants now.
This study's enrollment of 113 is below the median of 150 across 155 interventional studies indexed under Atrial Flutter.
Browse Atrial Flutter studies →Liverpool Heart and Chest Hospital NHS Foundation Trust is the lead sponsor of 33 studies on the registry; 6 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 recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
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.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TIA (transient ischaemic attack)
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
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.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Radiofrequency ablation of CTI (cavo-tricuspid isthmus), which is the 'conventional' treatment of atrial flutter
Procedure: Radiofrequency ablation of CTI
Cryoballoon PVI (Pulmonary Vein Isolation), which is the 'novel treatment'
Procedure: Cryoballoon PVI
Delivery of radiofrequency energy to the cavotricuspid isthmus (region of right atrial tissue between the tricuspid annulus and the inferior vena cava) until bidirectional block is achieved
Also known as: CTI ablation
Cryoballoon application to the pulmonary veins aiming for Pulmonary Vein Isolation
Also known as: Cryoablation Pulmonary Vein Isolation
Time to first recurrence of sustained, symptomatic supraventricular arrhythmia (Atrial Fibrillation, Atrial Flutter or Atrial Tachycardia) following a blanking period of 4 weeks after a single ablation procedure
'Sustained' is defined as lasting \>30 seconds. 'Symptomatic' is defined as acute onset awareness of palpitations, breathlessness, dizziness, fatigue or chest pain associated with patient activation of the loop recorder.
Time frame: After 4 weeks of ablation treatment (blanking period) up to 12 months of follow up
Time to first symptomatic or asymptomatic Atrial Fibrillation lasting ≥2 min
How long it takes until first occurrence of atrial fibrillation (associated with symptoms or no symptoms) lasting 2 or more minutes after blanking period. Two minutes is the minimum duration detectable by the loop recorder
Time frame: After 4 weeks of ablation treatment (blanking period) up to 12 months of follow up
Total Burden of Atrial fibrillation over 12 months
The total occurrence of atrial fibrillation recorded by the loop recorder (symptomatic or asymptomatic) during the follow-up period
Time frame: After 4 weeks of ablation treatment (blanking period) up to 12 months of follow up
Time to first symptomatic or asymptomatic atrial flutter/atrial tachycardia
Occurrence of atrial flutter/atrial tachycardia with/without symptoms following the blanking period
Time frame: After 4 weeks of ablation treatment (blanking period) up to 12 months of follow up
Incidence of any significant arrhythmia
Incidence of any arrhythmia requiring medical visit to primary or secondary care, or hospitalisation, or leading to death
Time frame: After first ablation procedure, through study completion, an average of 12 months
Total burden of abnormal heart rhythm measured by the implantable loop recorder
Total arrhythmic burden up to end of follow up or up to time of intervention (either cardioversion or ablation), whichever comes first.
Time frame: After first ablation procedure through study completion or time of intervention, whichever comes first, assessed up to 12 months
Incidence of repeat electrophysiological interventional procedure (repeat catheter ablation, or DCCV) over the follow-up period.
Occurrence of repeat ablations/cardioversion
Time frame: After 4 weeks of ablation treatment (blanking period) up to 12 months of follow up
Incidence of procedural complications
Composite of cardiac tamponade requiring drainage, persistent phrenic nerve palsy lasting \>24 hours, serious vascular complications requiring intervention or delaying discharge, stroke/transient ischaemic attack, requirement for a permanent pacemaker, atrio-esophageal fistula, or death
Time frame: During and after ablation procedure, through study completion, an average of 12 months
Incidence of all-cause hospitalisations
Any hospital admission post-ablation
Time frame: After first ablation procedure, through study completion, an average of 12 months
Quality of Life questionnaire
Quality of life as assessed by the standard EuroQol Group's 5-dimensional questionnaire. This comprises 5 dimensions (mobility, self-care, usual activities, pain/discomfort and anxiety/depression) and the visual analogue scale. The single digits for the five dimensions will be combined into a 5-digit number that describes the patient's health state.
Time frame: At baseline and at 12 months
Procedural duration
Duration of ablation measured in minutes for either treatment
Time frame: Only during the first ablation procedure
Total Fluoroscopy times
The total time in minutes during which patient will be exposed to radiation under each of the two treatment techniques
Time frame: Only during the first ablation procedure
Plan to share: No — There is no plan to share Individual Participant Data with other researchers. Supporting information that will be shared are only: Study Protocol, Statistical Analysis Plan (SAP), and Clinical Study Report (CSR) Data will be available after about 6 months for about 5 years. Criteria for which Individual Participant Data and any additional supporting information will be shared, including with whom, for what types of analyses, and by what mechanism: These will be shared with research co-workers, for results, statistical analysis and conclusions. Communication of anonymized data will be done via secure mails and emails.
Ran from Aug 2018 to primary completion in Dec 2021, 39 months.
Of 55 interventional studies with no phase under Atrial Flutter, half reached primary completion within 31 months of starting (the median), counting those still running; a quarter within 14 and three quarters within 63. This study's 39 months is above that.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Nov 2023. You cannot join it, but the record below documents what was studied.
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Liverpool Heart and Chest Hospital NHS Foundation Trust