Manual Versus Robotic Catheter Ablation for the Treatment of Atrial Fibrillation

Practical guidance to reduce radiation exposure in electrophysiology applying ultra low-dose protocols: a European Heart Rhythm Association review

Interventional electrophysiology offers a great variety of treatment options to patients suffering from symptomatic cardiac arrhythmia. Catheter ablation of supraventricular and ventricular tachycardia has globally evolved a cornerstone in modern arrhythmia management. Complex interventional electrophysiological procedures engaging multiple ablation tools have been developed over the past decades. Fluoroscopy enabled interventional electrophysiologist throughout the years to gain profound knowledge on intracardiac anatomy and catheter movement inside the cardiac cavities and hence develop specific ablation approaches. However, the application of X-ray technologies imposes serious health risks to patients and operators. To reduce the use of fluoroscopy during interventional electrophysiological procedures to the possibly lowest degree and to establish an optimal protection of patients and operators in cases of fluoroscopy is the main goal of modern radiation management. The present manuscript gives an overview of possible strategies of fluoroscopy reduction and specific radiation protection strategies.

What we have learned: is pulmonary vein isolation still the cornerstone of atrial fibrillation ablation?

Ablation of atrial fibrillation (AF) is an established treatment option for symptomatic patients. The cornerstone of all ablation strategies is electrical isolation of the pulmonary veins (PVs). Ablation strategies going beyond PV isolation (PVI) might be considered in the setting of recurrent AF despite durably isolated PVs. The lack of persistent PVI, however, limits the opportunities to perceive the real impact of this endpoint on AF suppression and to fully understand the benefit of extended ablation strategies going beyond. To overcome this limitation, novel and innovative ablation systems have been developed to facilitate acute PVI and to increase its durability. These systems include balloon-based ablation devices incorporating different energy sources such as cryo energy, laser, or radiofrequency current, but also new energy sources such as pulsed field ablation as a non-thermal energy source. These technologies could advance catheter ablation of AF to an early stage of the disease and to the primary treatment tool. The current manuscript focuses on the past, the present, and the future value of PVI as the cornerstone for interventional treatment of AF and on how to achieve durable PVI during the first procedure and to further improve the clinical success rates of AF ablation. It also analyses extended ablation strategies going beyond PVI and their impact.

Quantification of Left Atrial Fibrosis in Patients After Pulmonary Vein Isolation Using the Second-Generation Cryoballoon

Left atrial (LA) fibrosis is associated with a poor outcome after atrial fibrillation (AF) ablation. This study examined the extent of low-voltage areas in patients with recurrence of atrial tachyarrhythmia (ATA) after CB-based pulmonary vein isolation (PVI).Sixty patients (mean age 67 ± 10 years, n = 32 female; n = 34 paroxysmal AF) who received radiofrequency redo-procedure due to recurrence of ATA within 6 months after CB-based PVI were included. A point-by point 3D-map was performed, and low-voltage sites were delineated based on bipolar voltage < 0.5 mV. The extent of fibrosis was categorized as stage A (0-10% of the LA wall), stage B (10-30%), stage C (30-50%), and stage D (> 50%).The median area of LA low-voltage sites was 28.9 (9; 50.3) cm², corresponding to 17.4 (6; 30.6) % of the LA wall surface. 17/60 (28.3%) patients were categorized as fibrosis stage A, 21/60 (35%) as stage B, 18/60 (30%) as stage C, and 4/60 (6.7%) as stage D. Patient age and LA diameter were associated with more pronounced LA fibrosis; the extent of LA fibrosis was significantly higher in patients with LA tachycardia (LAT) during redo-procedures (P < 0.01), and ablation of linear lesions was more often performed (P < 0.01).In patients after CB2-based PVI, expanded LA tissue fibrosis was associated with the occurrence of LAT and more extensive LA ablation during redo-procedures.

Atrial fibrillation ablation in patients with pulmonary lobectomy or pneumectomy: Procedural challenges and efficacy

BACKGROUND

Catheter ablation of atrial fibrillation (AF) in patients with pulmonary lobectomy or pneumectomy is challenging due to anatomical alterations. After lung resection, electrically active pulmonary vein (PV) stumps remain and need to be localized for PV isolation (PVI). The present study aims to describe clinical challenges of PVI in patients with pulmonary lobectomy or pneumectomy.

METHODS

We performed a retrospective study on 19 patients with previous pulmonary lobectomy or pneumectomy undergoing catheter ablation for AF in three German hospitals.

RESULTS

Nineteen patients with paroxysmal, persistent, or longstanding-persistent AF and history of pulmonary lobectomy (n = 11) or pneumectomy (n = 8) were enrolled. Catheter ablation was performed as radiofrequency (RF) ablation using 3D mapping, robotic RF ablation, or by using balloon devices. Decent anatomical changes were observed in patients with lobectomy while cardiac rotation and mediastinal shifting was dominant in patients with pneumectomy. Visualization of all PVs including PV stumps by PV angiography was possible in 10 of 19 patients (52.6%). PV spikes were observed in all identified PV remnants. In nine patients (47.4%), at least one PV remnant could not be identified and electrical isolation was not performed. During 24 months follow-up, patients with incomplete PVI had a significantly shorter arrhythmia-free survival than patients with complete PVI (76.2% [95% Confidence interval (CI) 47.2-100.0%] vs 40.0% [95% CI 5.6-74.1%], P = .043).

CONCLUSION

In patients with AF and previous lobectomy or pneumectomy, identification and isolation of all PVs are challenging but crucial for ablation success. Additional imaging techniques may be necessary to achieve complete PVI.

Catheter Ablation of Atrial Fibrillation: State of the Art and Future Perspectives

PURPOSE OF REVIEW

Atrial fibrillation (AF), the most common sustained arrhythmia, is associated with high rates of morbidity and mortality. Maintenance of stable sinus rhythm (SR) is the intended treatment target in symptomatic patients, and catheter ablation aimed at isolating the pulmonary veins provides the most effective treatment option, supported by encouraging clinical outcome data. A variety of energy sources and devices have been developed and evaluated. In this review, we summarize the current state of the art of catheter ablation of AF and describe future perspectives.

RECENT FINDINGS

Catheter ablation is a well-established treatment option for patients with symptomatic AF and is more successful at maintaining SR than antiarrhythmic drugs. Antral pulmonary vein isolation (PVI) as a stand-alone ablation strategy results in beneficial clinical outcomes and is therefore recommended as first-line strategy for both paroxysmal and persistent AF. While radiofrequency-based PVI in conjunction with a three-dimensional mapping system was for many years considered to be the "gold standard", the cryoballoon has emerged as the most commonly used alternative AF ablation tool, especially in patients with paroxysmal AF. Patients with persistent or long-standing persistent AF and with arrhythmia recurrence after previous PVI may benefit from additional ablation strategies, such as substrate modification of various forms or left atrial appendage isolation. New technologies and techniques, such as identification of the AF sources and magnetic resonance imaging-guided substrate modification, are on the way to further improve the success rates of catheter ablation for selected patients and might help to further reduce arrhythmia recurrence.

CONCLUSIONS

Pulmonary vein isolation is the treatment of choice for symptomatic patients with paroxysmal and persistent drug-refractory AF. The reconnection of previously isolated pulmonary veins remains the major cause of AF recurrence. Novel ablation tools, such as balloon technologies or alternative energy sources, might help to overcome this limitation. Patients with non-paroxysmal AF and with AF recurrence might benefit from alternative ablation strategies. However, further studies are warranted to further improve our knowledge of the underlying mechanisms of AF and to obtain long-term clinical outcomes on new ablation techniques.

[Safety and efficiency of interventional electrophysiology utilizing the German "Belegarztsystem"]

INTRODUCTION

Electrophysiology study (EPS) and catheter ablation (abl.), in particular for atrial fibrillation, are increasingly performed in Germany. Therefore, measures and steps to ensure quality assurance are indicated. Most of the procedures are performed by physicians employed by hospitals; however, some are also carried out by attending cardiologists on contract in private practice, applying the so-called Belegarztsystem. The aim of this study was to determine the safety and efficiency of an interventional electrophysiology performed in a German Belegarztsystem.

METHODS

Based on a prospective registry, we analyzed procedure-related data from 1400 consecutive EPS/abl. performed at our center between 2014 and 2018. One-year follow-up data (arrhythmia recurrences, complications, deaths) were collected for all procedures carried out during the first 2 years.

RESULTS

In the total study cohort, no periprocedural death occurred, and there was a low cumulative incidence of groin complications (0.9%). The most common procedure (n = 772) was complex ablation for atrial fibrillation/flutter (55%). In this group, the success rate was 98% (acute) and 65% (1 year), and the cumulative rate of complications was 5.0% (transient ischemic attack/stroke 0.1%, pericardial tamponade 0.4%, relevant pericarditis/pericardial effusion 1.1%, groin complication 1.5%, other 1.9%). For the other procedures, rates for success and complications were comparable, and procedure times and x‑ray doses tended to be lower in our analysis as compared to prior reports.

CONCLUSION

Interventional electrophysiology, carried out by experienced operators and qualified staff, can be performed safely and effectively by attending physicians in a Belegarztsystem.

Feasibility, safety, and acute efficacy of the fourth-generation cryoballoon for ablation of atrial fibrillation: Another step forward?

Background

The second‐generation cryoballoon (CB2) is widely used for pulmonary vein (PV) isolation (PVI) in patients with paroxysmal atrial fibrillation (AF). Recently, the novel fourth‐generation CB (CB‐Advance PRO) was introduced, incorporating a shortened catheter tip.

Hypothesis

The aim of this study was to evaluate the feasibility and acute efficacy of PVI using the CB‐Advance PRO.

Methods

A total of 200 consecutive patients were analyzed. Hundred patients who underwent PVI due to symptomatic, drug‐refractory AF were treated with the CB‐Advance PRO (group I) and were included into this multicenter analysis. A group of 100 patients were treated with the CB2 and acted as controls (group II).

Results

In total, 739 of 739 PVs (100%) were successfully isolated. There was a nonsignificant trend in the incidence of online registration of PV signals between both groups (group I: 77.9% vs group II: 71.4%, P = .09). Median time to PVI (time to isolation [TTI]) and mean total freezing time were significantly shorter when using the CB‐Advance PRO (group I: 33 [23, 50] vs group II: 40 [26, 60] seconds and group I: 166 ± 29 vs group II: 183 ± 38 seconds, P < .01). In three of 100 (3%) patients of group I and one of 100 (1%) patients of group II, a transient phrenic nerve palsy occurred (P = .62).

Conclusion

The use of the novel CB‐Advance PRO is feasible and associated with a significant reduction in mean TTI and mean total freezing time as compared to the CB2.

Partnering with robotic technology in electrophysiology: have we arrived at a tipping point?

PURPOSE OF REVIEW

Bring readers up to date on the rationale for, current state of, and promising innovations in remote and robotic technology in electrophysiology.

RECENT FINDINGS

There is a growing peer-reviewed literature regarding existing nontraditional technology for mapping and ablation. There also is accelerated innovation under early evaluation that promises significant impact.

SUMMARY

The development and adoption of remote technologies in electrophysiology has faced considerable challenges yet holds tremendous promise for our patients. First principles must include benefit for patients in both safety and effectiveness, optimization of the process for providers, and sound economic and clinical justification for integration into healthcare systems. The limitations of traditional methods and tools that dominate current practice are discussed as a rationale for considering remote robotic systems. The growing library of published outcomes as well as the emergence of promising new technology merits fresh consideration.

From early beginnings to elaborate tools: contribution of German electrophysiology to the interventional treatment of cardiac arrhythmias : The German Cardiac Society welcomes ESC in Munich 2018

Catheter ablation evolved from the early days of cardiac electrophysiology (EP), in which invasive electrophysiological studies were mainly a tool to find the correct diagnosis and to evaluate the most effective anti-arrhythmic drug for the patient. Today, catheter ablation is the most effective treatment option for patients suffering from supraventricular and ventricular arrhythmias. The understanding of cardiac arrhythmias and treatment strategies improved because of physicians and scientists from all over the world. The work of German cardiologists led to new achievements in the field of cardiac EP and catheter ablation. In this article, we summarize selective contributions of German EP centres in the field.

Nonfluoroscopic catheter ablation of paroxysmal atrial fibrillation

AIMS

Radiofrequency catheter ablation of atrial fibrillation (AF) is one of the most complex ablation procedures. Both patients and operators are exposed to scattered radiation. This study evaluated the safety and efficacy of intracardiac echo (ICE)-guided pulmonary vein isolation (PVI) without fluoroscopy.

METHODS

We retrospectively analyzed the data of 481 consecutive patients with paroxysmal AF undergoing radiofrequency PVI with the CARTO 3 system (Biosense Webster, Diamond Bar, CA, USA). ICE-guided PVI without fluoroscopy and without CT/MRI integration (Nonfluoro group) was performed for 245 patients, and conventional fluoroscopy-guided PVI (Fluoro group) was performed for 236 patients. The primary safety endpoint was the incidence of major adverse events. The primary efficacy endpoint was freedom from AF during follow-up. Secondary endpoints included procedure duration, fluoroscopy duration, and acute PVI rate.

RESULTS

Mean procedure times between groups were similar (108.8 ± 18.2 minutes in the Non-fluoro group vs 113.6 ± 26.8 minutes in the Fluoro group; P  =  not significant [NS]). Acute PVI was achieved in all patients, with mean radiofrequency application times of 43.4 ± 7.5 and 44.4 ± 10.7 minutes for the Nonfluoro and Fluoro groups, respectively (P  =  NS). The incidence of cardiac tamponade was 1.2% (3/245 patients) in the Nonfluoro group and 0.8% (2/236 patients) in the Fluoro group (P  =  NS). During 15.2 ± 4.1 months of follow-up, after a single procedure, AF recurrence was documented in 65 of 245 (26.5%) patients and 61 of 236 (25.8%) patients in the Nonfluoro and Fluoro groups, respectively (P  =  NS).

CONCLUSIONS

Nonfluoroscopic ICE-guided catheter ablation of AF without prior cardiac image integration or angiography is feasible and safe. PVI without fluoroscopy did not affect procedure duration or long-term efficacy.