Thoracoscopic Ablation for Lone Atrial Fibrillation

Study Overview
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Brief Summary
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Background: Thoracoscopic ablation is an effective treatment of patients with atrial fibrillation. Nowadays, 2 types of ablative devices are available in clinical practice allowing one to perform the thoracoscopic procedure - Medtronic and AtriCure. However, the contemporary clinical literature does not have enough data that would compare these two approaches. Aims: to perform a comparative analysis of the short-term results of two minimally invasive strategies in thoracoscopic ablation for atrial fibrillation. Methods: The retrospective study was performed in which included 232 patients underwent thoracoscopic ablation for atrial fibrillation in two clinical centers for the period from 2016 to August 2021. The patients were divided into 2 groups. The first group was represented by those patients to whom a Medtronic device was applied (n=140), the second group was treated with an AtriCure device (n=92). The patients were comparable in their age, gender, initial severity of the condition. The follow-up consisted of laboratory tests, chest Х-ray, electrocardiography, 24-hour Holter monitor, echocardiography. The structure and prevalence of intraoperative and postoperative complications, specifics of the postoperative period were compared between the two groups.

Detailed Description
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Patients of the thoracoscopic group were divided into 3 subgroups: I - low (no HF), II - medium (possible) and III - high risk of HF (HF confirmed) (Table 1). A statistically significant difference was found for the indicator: age (in the high probability group in relation to the low probability group by an average of 5.5 years; p=0.002) (Table 1). The clinical characteristics of patients in the studied subgroups are presented in Table 2, no significant difference was found for any of the compared indicators. The nature of the cardiac arrhythmia and the severity of clinical symptoms are presented in Table 3. Significant differences were obtained for the following indicators: CHADS2VASc (in group III, high probability in relation to group I, low probability by an average of 1 point; p=0.008); HFA-PEFF (in group III, high probability by relative to group I low probability by an average of 5 points; p<0.001). Also, significant dynamics was obtained by the frequency of diagnosis of paroxysmal and long-lasting persistent forms of AF (p=0.025). Significant differences were obtained in the number of patients with 3 FC of heart failure (in group III, compared with group I, 5.3% vs 0.0%, respectively)

Official Title
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Two Strategies in Thoracoscopic Ablation for Lone Atrial Fibrillation

Conditions
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Atrial Fibrillation, Heart Diseases

Intervention / Treatment
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* Procedure: Thoracoscopic surgical ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: persistent or long-lasting persistent form of atrial fibrillation; age over 18 years; failure of conservative therapy with the use of Class I and III antiarrhythmic drugs (Vaughan Williams classification); absence of marked structural pathology of the heart, requiring surgical treatment. Exclusion Criteria: secondary atrial fibrillation due to reversible cause (pericarditis, hyperthyroidism, TELA, pneumonia, hypokalemia, etc.); surgical interventions on thoracic or mediastinal organs; age less than 18 years; presence of indications for open heart surgery under conditions of artificial circulation; heart failure with ejection fraction less than 30%; acute cerebral circulation disorder less than 3 months old; acute myocardial infarction or coronary stenting less than 3 months old; active systemic infection; left atrial appendage thrombosis detected one day before surgery; hemodynamically significant atherosclerotic lesion of coronary arteries and myocardial ischemia at the time of indications for surgery (confirmed by functional tests and coronarography); presence of contraindications for direct and indirect anticoagulants; presence of concomitant diseases of other organs and systems, which can lead to death within the first 2 years after the operation.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: AtriCure<br>Group of patients to whom was applied AtriCure device during thoracoscopic ablation. | Procedure: Thoracoscopic surgical ablation<br>* Thoracoscopic surgical ablation is a minimally invasive procedure used to treat atrial fibrillation by creation Box Lesion Set using Radio Frequency Energy. Pulmonary veins isolation was performed using ablation clamps, whereas isolation of the posterior left atrium (box) was performed using a clamping Medtronic or a linear nonclamping AtriCure device.<br>|
| Active Comparator: Medtronic<br>Group of patients to whom was applied Medtronic device during thoracoscopic ablation. | Procedure: Thoracoscopic surgical ablation<br>* Thoracoscopic surgical ablation is a minimally invasive procedure used to treat atrial fibrillation by creation Box Lesion Set using Radio Frequency Energy. Pulmonary veins isolation was performed using ablation clamps, whereas isolation of the posterior left atrium (box) was performed using a clamping Medtronic or a linear nonclamping AtriCure device.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of intraoperative complications | The number of intraoperative complications (Mortality, Stroke, Transient ischaemic attack, Sternotomy for bleeding, Mini-sternotomy for bleeding, Mini-thoracotomy for bleeding, Bleeding with discontinuation of procedure) | Day 1 | 
| Postoperative complications | Postoperative complications: Major complications (Death, Reinterventions, Re-intubation without haemodynamic instability, Re-intubation due to haemodynamic instability, Venous lung infarction, Lung emboli, Permanent phrenic nerve paralysis, Stroke, Transient ischaemic attack, Atrium-oesophagus fistula, Myocardial infarction, Renal failure necessitating dialysis, Sepsis) and Minor complications (Pericardial fluid necessitating pericardiocentesis, Permanent pacemaker implantation, Thoracostomy drain, Infections, Delirium, Gastrointestinal bleeding) | 1 mounth | 
| Heart rhythm | Heart rhythm (sinus rhythm, atrial fibrillation, pacemaker rhythm) | at the time of discharge | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Recurrence of atrial fibrillation | Development of recurrence of atrial fibrillation after thoracoscopic ablation | period after 3 month - 5 year. | 
| Cardiac Remodeling | Assessment cardiac remodeling after thoracoscopic ablation (indexed left atrial volume, ejection fraction, systolic pulmonary artery pressure) | after discharge - 5 year | 
| Functional class of heart failure | Assessment of the functional class of heart failure after thoracoscopic ablation | 1-5 year. | 
| Stroke and Transitory ischemic attack | Development of Stroke and Transitory ischemic attack after thoracoscopic ablation | after discharge - 5 year | 
| Unplanned cardiovascular hospitalization | Unplanned non-cardiovascular hospitalization after thoracoscopic ablation | after discharge - 5 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Thoracoscopic ablation, Atrial Fibrillation, Ablation technique