Hemolysis During Pulsed-field and Radiofrequency Ablation

Study Overview
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Brief Summary
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Hemolysis during and after catheter ablation will be compared between catheter ablation performed using radiofrequency and pulsed-field energy. Consecutive patients indicated for catheter ablation for AF will be enrolled, catheter ablation will be done using standard catheters (Qdot, Biosense Webster for RF, and Farapulse, Boston-Scientific for PF). Blood samples will be drawn at the beginning of ablation (T1), at the end of ablation (T2), and one day after the procedure (T3). Hemolysis will be analyzed using flow cytometry, ELISA and standard biochemistry and compared between RF and PF patients, Primary hypothesis is that hemolysis level will be higher after PF ablation compared to RF ablation.

Detailed Description
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Catheter ablation presents the most effective treatment for atrial fibrillation (AF). It consists of the electrical isolation of the pulmonary veins. Several kinds of ablation energies can be used for the ablation. So far, the most often kind of energy was radiofrequency (RF) energy that leads to thermal destruction of the cardiac tissue. Newly, pulsed-field (PF) energy was developed for catheter ablation of AF. The use of PF energy consists in ultra-short, high-power application of electrical impulses that lead to fast, non-thermal cardiac tissue destruction. Despite significant advantages, such as tissue selectivity, short procedure duration, and high durability of ablated lesions, the use of PF energy could also have other adverse effects. Recently, renal failure due to accelerated peri-procedural hemolysis in patients with pre-existed renal disease was described after PF ablation for AF. The aim of the project is to assess and compare the level of hemolysis during catheter ablation for AF using PF and RF energy. Sixty consecutive patients indicated for catheter ablation for AF according to the standard recommendation (symptomatic paroxysmal or non-paroxysmal AF) will be enrolled. Consecutive patients as they are scheduler for procedure will be enrolled without randomization. In 40 patients (20 paroxysmal and 20 non-paroxysmal), the ablation will be done using PF energy, and in 20 patients using RF energy. In all patients, intracardiac echocardiography (Accunav, Siemens, Germany) and fluoroscopy will be used for navigation. The procedures will be done as it is currently routinely done in the EP lab. In RF patients, 4 vascular access will be used (one for 10-pole catheter placed into the coronary sinus, one for intracardiac echocardiography probe, and 2 for transseptal sheaths). Two transseptal punctures will be done under the guidance of intracardiac echocardiography using SL1 sheaths (Abbott, USA). One transseptal access will be used for diagnostic circular mapping catheter (Lasso, Biosense-Webster, USA), the other for the ablation catheter. The RF ablation will be performed using SmartTouch or QDot ablation catheters (both Biosense-Webster, USA); however, ablation will be driven by the ablation index even if QDot catheter is used. The RF ablation will be performed using ablation index (400-450 on anterior-superior aspects and 350-400 on posterior aspects of PVs), the QDot Plus (high-power short-duration) regimen won´t be used. The goal will be to achieve the entrance and exit block of all 4 PVs. In non-paroxysmal patients, additional ablations could be done at the discretion of the treating physician (fractionated singnals, lines). In the PF patients, two vascular access will be obtained. The first will be used for intracardiac echocardiography, the second for the transseptal sheath. Transseptal puncture will be done also using SL1 sheath (Abbott, USA), and using over-the-wire technique, this sheath will be exchanged by the 16-F Faradrive sheath (BSCI, USA). The ablation then will be done using pentaspline ablation catheter (Farawave, Boston Scientific). Four application of pulsed-field energy in basket configuration, and 4 application in flower configuration will be applied to each pulmonary vein. Additional pulsed-field energy application could be added if the signal in PV are present. In non-paroxysmal patients, additional pulsed-field energy application could be applied on the discretion of the operator on the posterior wall, or mitral isthmus. Blood samples will be taken at the beginning of the procedure from the femoral vein (T1), at the end of the procedure after ablation lesions completion (T2), and one day after the procedure (T3). Hemolysis will be assessed in all three samples 1) using flow cytometry (by means of measurement of erythrocyte microparticles detected by the presence of antigens glycophorin A and Annexin V) and 2) using ELISA method (assessment of cell free hemoglobin  concentration). Additionelly, standard biochemistry and blood count analysis will be done from the T1 and T3 samples (the concentration of lactate dehydrogenase, haptoglobin, indirect bilirubin, reticulocytes, and immature reticulocyte fraction). Primary hypothesis is that the level of hemolysis will be higher after PF ablation compared to RF ablation. Since no studies were published on the hemolysis either during RF or PF ablation, no reliable power calculation can be done.

Official Title
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The Assessment of Intravascular Peri-procedural Hemolysis During Catheter Ablation for Atrial Fibrillation Using Radiofrequency and Pulsed-field Energy

Conditions
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Atrial Fibrillation, Hemolysis, Pulsed-field Ablation

Intervention / Treatment
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* Device: Pulsed-field ablation
* Device: Radiofrequency ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: symptomatic atrial fibrillation indicated for catheter ablation willingness to participate Exclusion Criteria: pregnancy any known malignant or non-malignant hematological disorder malignancy age > 75 years any disease associated with hemolysis hemoglobin concentration less than 100 g/L liver cirrhosis

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pulsed-field group<br>Patients will undergo catheter ablation for atrial fibrillation using pulsed-field energy | Device: Pulsed-field ablation<br>* Pulsed-field ablation will be done using pentaspline catheter (Farawave, Boston Scientific) and pulsed-field energy generator. The goal will be achieve of electrical isolation of pulmonary veins.<br>|
| Radiofrequency group<br>Patients will undergo catheter ablation using radiofrequency energx | Device: Radiofrequency ablation<br>* Pulmonary vein isolation will be done using radiofrequency catheter (Qdot, Biosense-Webster) and generator of radiofrequency energy (nGEN, Biosense-Webster).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Erythrocyte (red blood cells, RBC) microparticles | The concentration of erythrocyte microparticles /µL. Analysis using flow cytometry, as the concentration of total erythrocyte mictoparticles in platelet-rich plasma. | One day after the procedure | 
| Cell free hemoglobin | The concentration of cell-free hemoglobin, using ELISA measurement, in g/L | One day after the procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lactate-dehydrogenase | The concentration of lactate-dehydrogenase (µkat/L) | One day after the procedure | 
| Haptoglobin | The concentration of haptoglobin (g/L) | One day after the procedure | 
| Indirect bilirubin | The concentration of indirect bilirubin (µmol/L) | One day after the procedure | 
| Reticulocytes | The absolute concentration of reticulocytes | One day after the procedure | 
| Immature reticulocyte fraction (IRF) | The percentage of immature reticulocytes of all reticulocytes (%) | One day after the procedure |