Atrial Flutter
Conditions
Keywords
Atrial flutter, Cryoablation, Cavotricuspid isthmus, Visual analogue scale
Brief summary
The hypothesis of the present study is to evaluate cryoablation(cooling of the tissue) as standard therapy of common atrial flutter,focusing on efficacy, feasibility, procedure time, and patient content. The purpose of this study is to determine whether cryoablation, performed only by operators experienced in cryothermic ablation is effective and safe in the treatment of atrial flutter.
Detailed description
Atrial flutter (AFL), a common atrial tachyarrhythmia may cause significant symptoms and serious adverse effects including embolic stroke, myocardial ischemia and congestive heart failure. Currently, radiofrequency (RF) catheter ablation of the cavotricuspid isthmus (CTI) is considered first-line therapy for treatment of CTI-dependent AFL. However, RF ablation of the CTI is associated with significant pain during lesion delivery. Furthermore, RF ablation can potentially injure cardiac structures adjacent to the CTI such as the AV node, tricuspid valve and right coronary artery. RF ablation can also lead to steam pops, cardiac tamponade and fatal complications have also been reported in association with CTI-ablation. Ablation using cryothermal energy (Cryo) has several potential advantages over RF ablation including greater catheter stability due to adherence to myocardial tissue during applications, reduced risk of thrombus formation, systemic embolization, and lower risk of myocardial perforation due to preservation of tissue architecture. The investigators have in a prospective randomized, single centre study (CRAFT) investigated efficacy and safety of RF versus Cryo for atrial flutter, and showed that cryoablation is as effective as RF ablation in the short and long term. The patients perceived significantly less pain and required significantly lower doses of analgesia and sedation during cryoablation compared to RF ablation. The study was powered for non-inferiority with 75 patients in each group. The objective of the present study is to expand the findings from the CRAFT study in a larger cohort of patients, letting only operators experienced in cryothermic CTI ablation use Cryo as standard therapy focusing on efficacy, feasibility, procedure time, and patient content. To perform an ablation within the study, the electrophysiologist must have a previous experience of a minimum of 25 cryoablations of atrial flutter.
Interventions
PROCEDUREMedtronic Freezor Max Cardiac Cryoablation Catheter
Cryoablation is performed using a sequential application technique point-by-point from the tricuspid annulus to the inferior vena cava. Ablation is performed at a target temperature of -80 ºC. Each application will last for 240 seconds.
Sponsors
Karolinska University Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Consecutive patients referred to our institution for ablation therapy of ECG-documented, typical CTI dependent AFL. * Patients above the age of 18 having symptomatic CTI-dependent AFL documented on a 12-lead ECG with typical ECG appearance of negative saw tooth waves in the inferior limb leads and positive deflections in V1 or positive saw tooth waves in the inferior limb leads and negative deflections in V1. * Patients with a history of atrial fibrillation will only be included if they have predominant atrial flutter under chronic treatment with class I or III antiarrhythmic agents.
Exclusion criteria
1. prior ablation for AFL; 2. atrial flutter related to recently undergone surgery, hyperthyroidism or other severe disease; 3. inability to adhere with the study protocol; 4. pregnancy; 5. predominant atrial fibrillation; and 6. for patients with persistent atrial flutter contraindication to warfarin
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Efficacy | One year after intervention | Clinical success defined as the freedom from atrial flutter evaluated at the 12-month follow-up. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Safety | During and up to one year after intervention | The secondary endpoints will be acute ablation success defined as bidirectional CTI-block, safety assessed by the rate of periprocedural complications, procedure and fluoroscopy times and the level of pain experienced by the patient during the ablation procedure. |
Countries
Sweden
Outcome results
None listed