MINISTRY OF EDUCATION AND TRAINING MINISTRY OF DEFENCE 108 INSTITUTE OF CLINICAL MEDICAL AND PHARMACEUTICAL SCIENCES VIEN HOANG LONG CLINICAL, PARACLINICAL CHARACTERISTIC, ELECTROPHYSIOLOGICAL FEATURE[.]
MINISTRY MINISTRY OF EDUCATION AND TRAINING OF DEFENCE 108 INSTITUTE OF CLINICAL MEDICAL AND PHARMACEUTICAL SCIENCES VIEN HOANG LONG CLINICAL, PARACLINICAL CHARACTERISTIC, ELECTROPHYSIOLOGICAL FEATURES AND RESULT OF PERSISTENT ATRIAL FIBRILLATION ABLATION WITH RADIOFREQUENCY ENERGY Speciality: Internal Medicine/Internal Cardiology Code: 9720107 DISSERTATION ABSTRACTS HA NOI - 2023 THE DISSERTATION HAS BEEN COMPLETED AT 108 INSTITUTE OF CLINICAL MEDICAL AND PHARMACEUTICAL SCIENCES Supervisor 1: Assoc.Prof.PhD: Pham Quoc Khanh 2: Assoc.Prof.PhD: Pham Nguyen Son Reviewer 1: Reviewer 2: Reviewer 3: The thesis will be present in front of board of university examiner and reviewer lever at on 2023 This thesis can be found at: National Library: - National Medical Informatics Library - Library of 108 institute of clinical medical and pharmaceutical sciences LIST OF PUBLISHED PAPERS OF THE DISSERTATION Long V H., Khanh P Q., & Son P N (2023) Clinical characteristics and electrophysiological features in patients with persistent atrial fibrillation undergoing radiofrequency energy ablation Journal of 108 - Clinical Medicine and Pharmacy, 17(TA) https://doi.org/10.52389/ydls.v17iTA.1639 Long V H., Khanh P Q., & Son P N (2023) The results of persistent atrial fibrillation ablation with radiofrequency energy after a six-month follow-up Journal of 108 - Clinical Medicine and Pharmacy, 17(TA) https://doi.org/10.52389/ ydls v17iTA.1636 INTRODUCTION Urgency of research Over the past 20 years, atrial fibrillation (AF) has become one of the most investigated arrhythmias and has incurred significant healthcare costs in developed countries Besides causing symptoms and affecting quality of life, AF is a leading cause of systemic thromboembolism, stroke, heart failure, mortality, and increased hospital readmission rate in patients with cardiovascular disease According to the European Society of Cardiology statistics in 2016, there are approximately 43.6 million AF patients worldwide, and the incidence of AF increases with age and coexisting cardiovascular risk factors Unlike other arrhythmias, AF tends to progress from paroxysmal AF to persistent and eventually long-standing persistent AF over time Early rhythm control intervention for paroxysmal and persistent AF would reduce the progression to long-standing persistent AF Until now, there have been many advances in the management of AF with promising results In 1994, Haissenguerre M first applied radiofrequency energy to treat AF patients, but the success rate was low (33-60%), the complication rate was high, and the procedure took up to 5-6 hours From 1996, Pappone C used the three-dimensional CARTO cardiac mapping system to treat AF with radiofrequency energy Despite many advances and improvements in tools, techniques, and success rates in maintaining sinus rhythm after intervention for patients with persistent AF, the success rate is not as high as those with paroxysmal AF In addition, the cost of an ablation procedure for AF (especially in Vietnam) is also high Therefore, ablation intervention for persistent AF has not been widely performed and researched in Vietnam 2 Research objectives - To assess clinical, paraclinical characteristics and electrophysiological features of persistent atrial fibrillation patients - To evaluate results within 6-month follow-up after persistent atrial fibrillation ablation The scientific and practical significance of the research - Identifying associated atrial arrhythmias and accompanying substrate abnormalities in persistent atrial fibrillation patients, assessing cardiac electrophysiological characteristics after sinus rhythm restoration - Determining the success rate of maintaining sinus rhythm and changes in clinical symptoms of patients in the 6-month following-up persistent atrial fibrillation ablation using radiofrequency energy - Evaluating the correlation between early recurrence of atrial fibrillation (≤ months post-intervention), time from atrial fibrillation diagnosis to intervention, and the success rate of maintaining sinus rhythm after months This helps in selecting and predicting patients with a higher success rate for the treatment method The structure of the dissertation - The thesis consists of 87 pages (excluding references and appendices), structured into sections: Introduction (2 pages), Literature overview (9 pages), Subjects and Methods (18 pages), Results (30 pages), Discussions (25 pages), Conclusions (2 pages), Recommendations (1 page), and List of published papers of the dissertation (1 page) - Number of tables and figures: 39 tables, 16 figures, 17 pictures - The references of the dissertation include 108 sources, comprising Vietnamese references and 99 English references CHAPTER 1: LITERATURE OVERVIEW 1.1 Diagnosis of atrial fibrillation 1.1.1 Definition of atrial fibrillation: A supraventricular tachyarrhythmia with uncoordinated atrial electrical activation and consequently ineffective atrial contraction 1.1.2 Diagnostic criteria for atrial fibrillation The diagnosis of AF is based on an ECG tracing heart rhythm with no discernible repeating P waves and irregular R-R intervals ECG tracing of ≥ 30 seconds is diagnostic of clinical AF 1.1.3 Classification of AF - Paroxysmal AF: AF that terminates spontaneously or with intervention within days of onset - Persistent AF: AF that is continuously sustained beyond days, including episodes terminated by cardioversion (drugs or electrical cardioversion) after >_7 days - Long-standing persistent AF: Continuous AF of >12 months’ duration when decided to adopt a rhythm control strategy - Permanent AF: AF that is accepted by the patient and physician, and no further attempts to restore/maintain sinus rhythm will be undertaken 1.2 Atrial fibrillation management 1.2.1 ACB pathway: According to ESC AF guideline 2020, the simple Atrial fibrillation Better Care (ABC) was recommended for AF management A: Anticoagulation/Avoid Stroke B: Better symptom control (choose rhythm control or rate control strategy) C: Cardiovascular risk factors and concomitant diseases control 1.2.2 Indications for atrial fibrillation catheter ablation According to 2017 HRS/EHRA/ECAS/APHRS/SOLAECE guideline: Indications for symptomatic paroxysmal AF was Class IA, persistent AF was IIa-B In ESC 2020 guidelines recommend persistent AF ablation in symptomatic patients with low risk of recurrence and failure of medical therapy as a class I recommendation 1.3 Recent studies about atrial fibrillation catheter ablation 1.3.1 Overview of study about atrial fibrillation in Vietnam Currently, in Vietnam, the majority of research on AF is conducted on patients with other comorbidities Only one study by Pham Tran Linh has evaluated the effectiveness of ablative intervention in paroxysmal AF patients There has been no research conducted on ablative intervention in persistent AF patients 1.3.2 Overview of studies about persistent atrial fibrillation ablation AF ablation intervention is also one of the outstanding issues of concern in the world Author groups have proposed new ablation strategies to improve success rates for the AF patient group, especially for persistent AF (Verma A., He X., Kottkamp H Stavakis S ) CHAPTER 2: OBJECTS AND METHODS 2.1 Study objects Our study included 40 persistent atrial fibrillation patients, all of these patients were hospitalized and underwent catheter ablation of atrial fibrillation at Vietnam National Heart Institute - Bach Mai Hospital from October 2017 to November 2021 2.1.1 Inclusion criteria According to 2016 atrial fibrillation guidelines of the European Society of Cardiology (ESC) and the Vietnam Society of Cardiology / Vietnamese Society of Cardiology Electrophysiology (IIa recommendation with level of evidence C), patients who meet the following conditions are indicated for catheter ablation: - Patients with clinical symptoms who are unresponsive or intolerant to at least one antiarrhythmic drug in group I or III - Patients with clinical symptoms despite the use of antiarrhythmic drugs in group I or III and who desire a rhythm control strategy 2.1.2 Exclusion criteria - Paroxysmal AF, permanent AF, age < 18 years old, elderly patients (age ≥ 80 years), thrombus in the heart chamber, heart failure with reduced ejection fraction (EF ≤ 49%), recent stroke, Acute infection and blood clotting disorder 2.1.3 Diagnostic criteria used in the study Arterial hypertension: is defined according to 2018 ESC guidelines Diabetes is defined according to American Diabetes Association 2017 Excessive alcohol is defined according to U.S CDC guidance 2.2 Methods 2.2.1 Design and sample size A prospective intervention study with a 6-month follow-up using a convenient sample size 2.2.2 Data collection 2.2.2.1 Clinical examination and investigations All the patients were examined, recorded 12 – lead ECG Other investigations were done before procedures such as blood tests, chest X-ray, transthoracic echocardiography, trans esophagus echocardiography, multi-sliced CT scanner of left atrium and pulmonary veins 2.2.2.2 Catheter ablation and electrophysiology study - Place of procedures: Catheterization Laboratory, Vietnam Heart Institute, Bach Mai Hospital -Equipment: angiography system, stimulator, electrophysiological recording system, ablation generator, threedimensional mapping system (ENSITE system) and varieties of diagnostic catheters and ablation catheters - Procedure protocol +Placement of catheters: Diagnostic catheters were placed at the coronary sinus, right atrium, right ventricle, His bundle +Mapping catheters and ablation catheters were inserted through right femoral vein and transseptal to the left atrium - Ablation protocols: Completed pulmonary veins isolation Cardioversion convert to sinus rhythm, use Voltage mapping in sinus rhythm (setting: 0.2-0.5 mV) If patient had non -PVs foci, atrial flutter, atrial tachycardia, low voltage zone, we would add on ablation to PVI In sinus rhythm, measure intervals: Basic sinus rhythm cycle length, PA, AH, HV, QRS, QT, SNRT, cSNRT, ERP of atrial, ventricular and AV node + Criteria of success: confirmed both directional blocked after ablation 2.2.2.3 Follow-up after radio frequency catheter ablation + All the patients underwent 24-hour Holter ECG, transthoracic cardiac echo within 24 hours after catheter ablation + Patients were received antiarrhythmic months after procedures + Follow-up was carried out with 24 – hour ECG, cardiac echo, blood test after month, months, months Chart 2.1 Study's protocol 2.3 Statistical analysis The t-test was used to compare two mean values, and the chisquare test (2) was used to compare two percentages p-value