Catheter ablation versus antiarrhythmic drugs with risk factor modification for treatment of atrial fibrillation: a protocol of a randomised controlled trial (PRAGUE-25 trial)

INTRODUCTION

Atrial fibrillation (AF), with a prevalence of 2%, is the most common cardiac arrhythmia. Catheter ablation (CA) has been documented to be superior to treatment by antiarrhythmic drugs (AADs) in terms of sinus rhythm maintenance. However, in obese patients, substantial weight loss was also associated with AF reduction. So far, no study has compared the modern non-invasive (AADs combined with risk factor modification (RFM)) approach with modern invasive (CA) treatment. The aim of the trial is to compare the efficacy of modern invasive (CA) and non-invasive (AADs with risk factor management) treatment of AF.

METHODS AND ANALYSIS

The trial will be a prospective, multicentre, randomised non-inferiority trial. Patients with symptomatic AF and a body mass index >30 will be enrolled and randomised to the CA or RFM arm (RFM+AAD) in a 1:1 ratio. In the CA arm, pulmonary vein isolation (in combination with additional lesion sets in non-paroxysmal patients) will be performed. For patients in the RFM+AAD arm, the aim will be a 10% weight loss over 6-12 months, increased physical fitness and a reduction in alcohol consumption. The primary endpoint will be an episode of AF or regular atrial tachycardia lasting >30 s. The secondary endpoints include AF burden, clinical endpoints associated with AF reoccurrence, changes in the quality of life assessed using dedicated questionnaires, changes in cardiorespiratory fitness and metabolic endpoints. An AF freedom of 65% in the RFM+AAD and of 60% in the CA is expected; therefore, 202 patients will be enrolled to achieve the non-inferiority with 80% power, 5% one-sided alpha and a non-inferiority margin of 12%.

ETHICS AND DISSEMINATION

The PRAGUE-25 trial will determine if modern non-invasive AF treatment strategies are non-inferior to CA. The study was approved by the Ethics Committee of the University Hospital Kralovske Vinohrady. Results of the study will be disseminated on scientific conferences and in peer-reviewed scientific journals. After the end of follow-up, data will be available upon request to principal investigator.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT04011800).

Telemedicine in arrhythmology

Telemedicine can be defined as a health care service that, specifically in the field of diagnostics, employs remote transfer of a large volume of data from a large number of subjects at the same time. This data is subsequently processed on a central basis and returned to a large number of health care providers by whom the service was ordered on national or international level. In arrhythmology, telemedicine is used particularly in long-term ECG monitoring to diagnose arrhythmias and check out treatment outcome via external recorders, smart watch, and implantable devices. To facilitate analysis of large telemedicine data volume, artificial intelligence is being increasingly exploited.

Long-term ECG monitoring

ECG recording represents an essential method for the diagnosis of heart rhythm disturbances. Long-term monitoring helps to identify arrhythmias that have not been detected by means of standard 12-lead ECG or 24-48 hour ECG Holter. With time, ECG monitoring facilities improve, the ECG recorders are becoming smaller, and the recording time is prolonging. At present, continuous ECG recording is generally available. Smart watches and fitness bracelets further expand monitoring options in patients with known or suspected arrhythmia. Individual type and frequency of symptoms remain the most significant criterion for the selection of suitable ECG recorder and recording time.

Functional improvement after successful catheter ablation for long-standing persistent atrial fibrillation

Aims

Identifying patients who benefit from restored sinus rhythm (SR) would optimize the selection of candidates for ablation of long-standing persistent atrial fibrillation (LSPAF). This prospective study sought to identify the hitherto unknown factors associated with global functional improvement after successful radiofrequency catheter ablation of LSPAF.

Methods and results

In 171 LSPAF patients (84% of the total consecutive 203 patients) who were examined in SR 12 months after ablation, the individual per cent change from baseline value in maximum oxygen consumption at exercise test (VO2 max), left ventricular ejection fraction (LVEF), N-terminal prohormone of brain natriuretic peptide (NT-proBNP), and five-dimensional descriptive system (EQ-5D) of quality-of-life questionnaire were classified in quartiles by 0 (worse) to 3 (best) grades. The individual grades were summed into a composite score (SCORE, 0 … 12) reflecting global functional improvement. Significant improvement in VO2 max (3.4 ± 4.7 mL/kg/min), LVEF (7.5 ± 9.1%), NT-proBNP (-861 ± 809 pg/mL), and EQ-5D (0.7 ± 0.12) was observed (all P < 0.0001). On multivariable analysis, younger age (P = 0.001), male gender (P = 0.02), timely post-ablation left atrial appendage (LAA) outflow (P = 0.005) with improvement in outflow velocity (P = 0.0002), and withdrawal of Class I/III antiarrhythmic drugs (P < 0.05) were positively and independently correlated with the SCORE.

Conclusions

Younger male patients benefited most from catheter ablation of LSPAF. Delayed or non-improved LAA outflow and inability to discontinue Class I/III antiarrhythmic medication reduced the post-ablation functional improvement.

Disparity between two-dimensional echocardiographic and electroanatomic left and right atrial volumes in patients undergoing catheter ablation for long-standing persistent atrial fibrillation

Left atrial (LA) volume (LAV) is used for the selection of patients with atrial fibrillation (AF) to rhythm control strategies. Calculation of LAV from the LA diameters and areas by two-dimensional (2D) echocardiography may result in significant error. Accuracy of atrial volume assessment has never been studied in patients with long-standing persistent AF (LSPAF) and significant atrial remodeling. This study investigated correlation and agreement between 2D echocardiographic (Simpson method) and electroanatomic (CARTO, Biosense Webster) left and right atrial (RA) volumes (LAV(ECHO) vs. LAV(CARTO) and RAV(ECHO) vs. RAV(CARTO)) in patients undergoing catheter ablation for LSPAF. The study enrolled 173 consecutive subjects (females: 21 %, age: 59+/-9 years). There was only modest correlation between LAV(ECHO) (92+/-31 ml) and LAV(CARTO) (178+/-37 ml) (R=0.57), and RAV(ECHO) (71+/-29 ml) and RAV(CARTO) (173+/-34 ml) (R=0.42), respectively. LAV(ECHO) and RAV(ECHO) underestimated LAV(CARTO) and RAV(CARTO) with the absolute bias (+/-1.96 standard deviation) of -85 (-148; -22) ml and -102 (-169; -35) ml, respectively, and with the relative bias of -48 (-75; -21) % and -59 (-88; -30) %, respectively (all P<0.000001 for their mutual difference). Significant confounders of this difference were not identified. In patients with LSPAF, 2D echocardiography significantly underestimated both LA and RA volumes as compared with electroanatomic reference. This disagreement was independent of clinical, echocardiographic and mapping characteristics.

Sinus rhythm restoration and arrhythmia noninducibility are major predictors of arrhythmia-free outcome after ablation for long-standing persistent atrial fibrillation: a prospective study

BACKGROUND

The impact of restoring sinus rhythm (SR) by initial ablation in patients with long-standing persistent atrial fibrillation (LSPAF) is not fully established.

OBJECTIVE

The purpose of this study was to investigate the prognostic value of SR restoration at the initial procedure and arrhythmia noninducibility at the final repeat procedure for long-term outcome.

METHODS

A total of 203 patients (22% female; age 59 ± 9 years) underwent stepwise catheter ablation for LSPAF.

RESULTS

The procedural end-point of SR restoration was achieved in 50% of patients. During follow-up (median 48 months) and after 1.7 procedures per patient, 72% of patients were free from arrhythmia off antiarrhythmic drugs. Failure to restore SR was independently predicted by left atrial (LA) long-axis diameter ≥68 mm (relative risk [RR] 1.55, P = .03], proportion of high-voltage LA sites <20% (RR 1.62, P = .02), and left atrial appendage (LAA) atrial fibrillation cycle length (AFCL) <155 ms (RR 1.5, P = .05). Arrhythmia recurrence after the initial procedure was predicted by SR nonrestoration (RR 2.99, P <.000001) and LAA AFCL ≥155 ms (RR 1.90, P = .0002). Arrhythmia recurrence after the final procedure was predicted by SR nonrestoration at the initial procedure (RR 2.83, P = .0007), persistent AF duration ≥24 months (RR 2.74, P = .002), LAA outflow velocity <40 cm/s (RR 2.21, P = .006), and LAA AFCL ≥155 ms (RR 1.92, P = .02). In 115 patients with repeat procedure(s), failure to achieve arrhythmia noninducibility at the final procedure (19% of patients) was associated with arrhythmia recurrence (RR 8.9, P < .000001).

CONCLUSION

SR restoration at the initial procedure and arrhythmia noninducibility at the last repeat procedure were major predictors of arrhythmia-free outcome after ablation for LSPAF.

Improvement in quality of life after catheter ablation for paroxysmal versus long-standing persistent atrial fibrillation: a prospective study with 3-year follow-up

BACKGROUND

Changes in quality of life (QoL) after catheter ablation for long-standing persistent atrial fibrillation (LSPAF) are not well described. We sought to compare QoL improvement after catheter ablation of paroxysmal atrial fibrillation (PAF) versus that after LSPAF.

METHODS AND RESULTS

A total of 261 PAF and 126 LSPAF ablation recipients were prospectively followed for arrhythmia recurrence, QoL, hospital stay, and sick leave. In PAF versus LSPAF groups, 1.3±0.6 versus 1.6±0.7 procedures were performed per patient (P<0.00001) during a 3-year follow-up. Good arrhythmia control was achieved in 86% versus 87% of patients (P=0.69) and in 69% versus 69% of patients not receiving antiarrhythmic drugs (P=0.99). The baseline QoL was better in the PAF than in the LSPAF group (European Quality of Life Group instrument self-report questionnaire visual analog scale: 66.4±14.2 versus 61.0±14.2, P=0.0005; European Quality of Life Group 3-level, 5-dimensional descriptive system: 71.4±9.2 versus 67.7±13.8, P=0.002). Postablation 3-year increase in QoL was significant in both groups (all P<0.00001) and significantly lower in PAF versus LSPAF patients (visual analog scale: +5.0±14.5 versus +10.2±12.8, P=0.001; descriptive system: +5.9±14.3 versus +9.3±13.9, P=0.03). In multivariate analysis, LSPAF, less advanced age, shorter history of AF and good arrhythmia control were consistently associated with postablation 3-year improvement in QoL. Days of hospital stay for cardiovascular reasons and days on sick leave per patient/year were significantly reduced in both groups.

CONCLUSIONS

Patients with LSPAF had worse baseline QoL. The magnitude of QoL improvement after ablation of LSPAF was significantly greater compared with after ablation of PAF, particularly when good arrhythmia control was achieved without the use of antiarrhythmic drugs.

[Outcomes of catheter ablation of atrial fibrillation in patients over 65 years of age]

PURPOSE

This study assessed ablation techniques, recurrent arrhythmias, long-term outcomes, and complications of catheter ablation for atrial fibrillation (AF) in patients 65 years of age.

METHODS

Consecutive patients aged < 65 years (n = 653) vs 65 years (n = 213), who underwent catheter ablation of AF in the course of eight years, were compared. Ablation strategy and procedure endpoints were left at the operators discretion.

RESULTS

The group of patients 65 years comprised more females (p < 0.001), and more frequently presented with persistent AF (p = 0.010). These patients less frequently underwent simple pulmonary vein isolation (p = 0.017); on the contrary, extensive ablation including coronary sinus intervention was more common (p = 0.020). There was no difference in repeat ablation procedures (25 % vs 26 % patients; p = 0.823, or 1.4 vs 1.5 ablation procedures/1 patients; p = 0.479, respectively). Spectrum of recurrent arrhythmias did not differ between the groups except for more frequent paroxysmal AF before the first repeat ablation in patients < 65 years (p = 0.050). At the end of 49 ± 26 month total follow-up, stable sinus rhythm (SR) was achieved in 85 % patients < 65 years vs 76 % patients 65 years (p = 0.318). To maintain stable SR, older patients more often continued to take antiarrhythmic medication (p = 0.054). More serious complication occurred in 3.8 % of the patients 65 years vs 2.1 % of the patients < 65 years of age (p = 0.207).

CONCLUSION

Patients 65 years of age achieved insignificantly worse long-term outcome after insignificantly fewer repeat ablation procedures, and with more frequent use of antiarrhythmic drugs. SR maintenance and risk of complications were, however, favorable.

[A comparison of two methods of long-term external ECG telemonitoring in patients after ablation for atrial fibrillation]

AIM

The aim of the study was to compare two methods of long-term ECG monitoring after atrial fibrillation (AF) ablation.

METHODS

The study included 279 patients with paroxysmal (n = 163) or persistent (n = 116) AF, who were followed up for 1 year after the first catheter ablation for AF. All patients were provided with episodic ECG recorder for 1 year and instructed to send at least 2 random ECG recordings per day and whenever they sensed symptoms. They were also provided with external loop recorder for 2-3 weeks at 6 and 12 months to enable more continuous ECG monitoring.

RESULTS

At the end of 39 ± 12 (12-60) month follow-up, 143 (88%) patients with paroxysmal AF, and 105 (91%) patients with persistent AF, respectively, remained in stable sinus rhythm. The efficacy of episodic recorder expressed as a ratio of patients with identified AF/atrial tachycardia (AT) out of all patients with a documented episode of AF/AT was superior to the efficacy of loop recorder. No AF/AT episode was recorded with the loop recorder that was not also documented by the episodic recorder. Of the patients with the AF/AT recurrence detected by the episodic recorder, the arrhythmia was also revealed by the loop recorder in 70% of the patients after paroxysmal AF ablation (p < 0.001), and in 52% of the patients after persistent AF ablation (p = 0.006). Asymptomatic AF/AT was present in 42 (26%) of patients with paroxysmal AF, and in 28 (24%) patients with persistent AF (p = 0.810). From conventional follow-up unexpected and clinically significant episode of AF/AT that required change in therapy was detected in 9 (5.5%) patients after ablation for paroxysmal AF, and in 4 (3.4%) patients after ablation for persistent FS.

CONCLUSION

More episodes of AF/AT after ablation were detected by 1-year daily ECG monitoring using episodic recorder as compared to periodic ECG monitoring with loop recorder. Identification of clinically significant episodes of AF/AT unrecognized from conventional follow-up was low.

[Catheter ablation of atrio-ventricular accessory pathways in the era of ablation therapy of complex arrhythmias: a changing perspective for oncoming generation of electrophysiologists]

INTRODUCTION

Catheter ablation of atrio-ventricular accessory pathways has become a routine treatment method. However, its perspective has been changing in the era of ablation of complex arrhythmias. This study was aimed at evaluating accessory pathways ablation efficacy within the last nine years at one center.

METHODS

From February 2002 to June 2011, catheter ablation of accessory pathways was performed in 247 patients (100 females, 42 ± 16 years). Elimination of accessory pathways conduction in both directions was the procedure endpoint.

RESULTS

Immediate accessory pathways conduction elimination at the first ablation was achieved in 228 (92%) patients. Ablation failed to eliminate accessory pathways conduction in 19 (8%) patients, or accessory pathways conduction subsequently recurred in another 7 (3%) patients. Repeat ablation was completed in 20 (8%) patients, 2 patients underwent a third ablation procedure. In total, accessory pathway was permanently eliminated in 238 (96%) patients. Ablation failure was connected with a risky position in the vicinity of atrio-ventricular conduction system in 6 (67 %) out of 9 patients. By the individual A, B, C, D operators experience, efficacy of the first procedure/total efficacy, was 97%/99%, 90%/96%, 87%/87%, and 91%/91%, respectively (comparison of inter-operator efficacy of the first and repeat ablation by Kruskal-Wallis ANOVA test: p = 0,19 and 0,05, respectively).

CONCLUSION

Accessory pathways ablation efficacy exceeds 95%, and ablation failure is dominantly related to the accessory pathways location close to the atrio-ventricular conduction system. Individual operator's experience was associated with a certain disparity between high and nearly absolute accessory pathways ablation efficacy.

[Improvement of quality of life after ablation of longstanding persistent versus paroxysmal atrial fibrillation: results of 2-year follow-up]

AIMS

The purpose of the study was to assess quality of life and socio-economic parameters in patients after ablation of paroxysmal versus longstanding persistent atrial fibrillation (AF).

METHODS

The study included 89 patients with paroxysmal AF and 56 patients with longstanding persistent AF who underwent ablation within 1 year, and were afterwards prospectively followed up for 2 years. Quality of life was evaluated by the EQ-5D questionnaire before and every 6 months after ablation.

RESULTS

Objective, respectively subjective quality of life at baseline was lower in patients with longstanding persistent AF (67 +/- 16 vs 71 +/- 10; p = 0.01, resp. 64 +/- 12 vs 67 +/- 16; p = 0.07); however, after 2 years, it exceeded that of the patients with paroxysmal AF (80 +/- 17 vs 75 +/- 18; p = 0.03; resp. 73 +/- 13 vs 70 +/- 17; p = 0.18). The baseline-2 year difference in improvement was higher in patients with longstanding persistent AF in both objective (p = 0.001) and subjective component (p = 0.05). Both groups displayed significant decrease in the days of hospitalization, and the days of working incapacity.

CONCLUSION

Patients with longstanding persistent AF exhibit worse baseline quality of life than the patients with paroxysmal AF, and higher quality of life improvement after ablation.

Characterization of residual coronary sinus-related tachycardia during ablation of longstanding persistent atrial fibrillation

PURPOSE

The aim was to characterize the coronary sinus (CS)-related tachycardia that occurred as the last residual arrhythmia and required ablation within the CS or great cardiac vein to restore sinus rhythm (SR) in patients with primary longstanding persistent AF.

METHODS

The study included 23 patients in whom stable SR was restored by ablation inside the vein during the first or repeat ablation.

RESULTS

The 23 subjects represented 23% of the 99 patients in whom SR was restored by ablation. A reentry tachycardia confined to the CS musculature was suggested in 8 (35%) patients, and a peri-mitral reentry circuit was present in 14 (61%) patients. Twenty (87%) patients have remained free from arrhythmia and class I or III antiarrhythmic drugs for 33 +/- 10 (12-53) months.

CONCLUSION

A majority of the residual CS-related tachycardias exhibit properties of reentry, one third utilizing the CS musculature as a reentry substrate independent of the atrial myocardium.

Septal ventricular tachycardia with alternating LBBB-RBBB morphology in isolated ventricular noncompaction

Knowledge on ventricular tachycardia (VT) in isolated ventricular noncompaction (IVNC) is limited. We report on a patient with IVNC who presented with cardiogenic shock due to an incessant drug-resistant VT that was cured by radiofrequency ablation. The VT had characteristics of a deep septal focal arrhythmia, which was distinctive by ablation-induced alternation of the rightward and leftward exits, and was difficult to ablate from either side of the ventricular septum.

[Conventional treatment of atrial fibrillation in the Czech Republic managed by outpatient cardiologists. Overview of diagnostic and treatment procedures, pharmacological treatment and hospitalisation]

OBJECTIVE

The aim of the study was to analyse general health data, diagnostic and therapeutic procedures, pharmacological treatment and hospitalization of patients with atrial fibrillation (AF) who did not undergo AF catheter ablation and were in the care of outpatient cardiologists.

METHOD

Data concerning 306 patients (of which 94 women, aged 64 +/- 11 years) for the preceding 2 years were acquired through a questionnaire containing a set of standardized questions on a simple form sent out to outpatient cardiologists.

RESULTS

AF was paroxysmal, persistent or permanent in 141 (46%), 77 (25%) or 88 (28%) patients, respectively. The higher the age, the lower the proportion of paroxysmal AF and the higher the proportion of the permanent form of AF. AF was asymptomatic in 122 (39%) of patients. The most frequent among cardiovascular diseases was hypertension, detected in 220 patients (72%), IHD was present in 83 patients (27%). The mean LV EF was 55 +/- 11% and was significantly lower in patients with permanent AF than in patients with paroxysmal AF (phi 51 +/- 13% vs. phi 58 +/- 9%, P < 0,001). The mean left atrium transversal diameter was 47 +/- 7 mm and was significantly higher in patients with permanent AF than in those with paroxysmal AF (50 +/- 8 mm vs. 44 +/- 6 mm, P < 0,001). 230 patients (75%) received anticoagulation treatment and 43 patients (14%) received antiaggregation treatment. 274 patients (90%) were taking antiarrhythmic drugs (AA); 93 patients were taking 1, 168 patients 2 and 13 patients 3 AA drugs. 167 patients (55%) underwent electrical cardioversion in 362 procedures, 106 patients (35%) underwent pharmacological cardioversion in 239 procedures. Coronarography was performed in 79 patients (26%) of which 59 (75%) had normal results for coronary arteries. Pacemaker due to concomitant sinus node dysfunction was implanted to 27 patients (9%). Ablation for concomitant atrial flutter of type I was performed in 42 patients (14%). AF and associated conditions caused 250 hospitalisations in 144 patients (47%). The average length of hospitalisation was 4.2 +/- 3.2 days. Cardioembolic event was the cause of hospitalisation of 25 patients (8%) out of 29 hospitalisations with the mean length of hospital stay 8.2 +/- 2.9 days.

CONCLUSION

The study has shown, in the first place, very high standards of anticoagulation and antiarrhythmic treatment. It has also shown a relatively frequent indication for coronarography, pacemaker implant for relative sinus node dysfunction or ablation for concomitant atrial flutter of type I, i.e. intervention procedures with limited benefit for AF patients.