Transseptal Access for Left Atrial Ablation: The Catheter-Probing Techniques Are Not Without Risk

Integrated dilator-needle transseptal crossing device in atrial fibrillation cryoballoon ablation procedures

INTRODUCTION

In cryoballoon ablation (CBA) procedures, transseptal access (TSA) is generally achieved using a standard sheath and needle system that is exchanged for the cryoballoon delivery sheath and dilator over a long wire. Sheath exchange has been related with air embolic events. Recently, an integrated dilator-needle system assembled to the cryoballoon sheath was introduced. We aimed to evaluate the efficacy and safety of an integrated TSA tool compared with the traditional approach in atrial fibrillation CBA procedures.

METHODS

Patients scheduled for CBA procedures were randomized 1:1 to traditional TSA (t-TSA) or integrated TSA (i-TSA). TSA time was defined as time from superior vena cava to LA insertion of the cryoballoon delivery sheath, after sheath exchange (t-TSA) or directly (i-TSA).

RESULTS

Ninety-seven patients (76 males, mean age 59 ± 10 years) were randomized, 48 patients underwent t-TSA, and 49 i-TSA. Mean TSA time was 5 min 59 s ± 5 min 36 s in the t-TSA group and 2 min 59 s ± 2 min 14 s in the i-TSA group (p < .001). Total fluoroscopy time, skin-to-skin procedure time, and LA dwell time were respectively 15 ± 6, 69 ± 16, and 44 ± 12 min in the t-TSA group and 13 ± 6, 65 ± 15, and 43 ± 11 min in the i-TSA group (p = ns). No clinically significant acute complications related to TSA were noted in both cohorts.

CONCLUSION

This is the first randomized study comparing both TSA approaches. TSA in CBA procedures using this integrated tool enables a safe and efficient workflow, reducing TSA time and avoiding sheath exchange.

Solving difficulties in transseptal sheath crossing: The shoehorn technique

The shoehorn technique is a simple and safe maneuver that can help to solve difficulties in challenging transseptal sheath crossing for atrial fibrillation cryoablation procedures.

Balloon mitral valvuloplasty: a re-emerging technique enhanced with real-time, three-dimensional transoesophageal cardiac ultrasound/echocardiography (3D-TOE)

We describe the case of a woman in her 60s with mitral stenosis, rate-controlled atrial fibrillation and a history of childhood rheumatic fever. She successfully underwent elective percutaneous transvenous mitral commissurotomy (PTMC), also described as balloon mitral valvuloplasty, for severe, symptomatic mitral stenosis. This was completed via right femoral vein access, trans-septal puncture and commissural separation guided by real-time three-dimensional (3D) transoesophageal echocardiography under general anaesthesia.Balloon mitral valvuloplasty is being completed more frequently in the UK due to the population having a higher incidence of mitral valve disease as a result of migration and as a palliative measure in those considered too high risk for mitral valve replacement cardiothoracic surgery.Rheumatic mitral stenosis is known to be a disease prevalent in countries of low and middle income and with increased migration to the UK, resulting in an increased prevalence of rheumatic mitral valve disease in the UK. It is estimated that within the UK, one in seven persons are migrants, and as such, we believe it is important to pay attention to diseases which affect the evolving population of the UK.Technological advancements, including availability and use of 3D transoesophageal cardiac ultrasound/echocardiography, have made PTMC much safer and more effective than previously. Additionally, the multidisciplinary team approach to PTMC is very important to its success. The procedure was completed successfully, with no complications.

Feasibility and safety of a three-dimensional anatomic map-guided transseptal puncture for left-sided catheter ablation procedures

AIMS

Transseptal puncture (TP) for left-sided catheter ablation procedures is routinely performed under fluoroscopic or echocardiographic guidance [transoesophageal echocardiography (TEE) or intracardiac echocardiography (ICE)], although three-dimensional (3D) mapping systems are readily available in most electrophysiology laboratories. Here, we sought to assess the feasibility and safety of a right atrial (RA) 3D map-guided TP.

METHODS AND RESULTS

In 104 patients, 3D RA mapping was performed to identify the fossa ovalis (FO) using the protrusion technique. The radiofrequency transseptal needle was visualized and navigated to the desired potential FO-TP site. Thereafter, the interventionalist was unblinded to TEE and the potential FO-TP site was reassessed regarding its convenience and safety. After TP, the exact TP site was documented using a 17-segment-FO model. Reliable identification of the FO was feasible in 102 patients (98%). In these, 114 3D map-guided TP attempts were performed, of which 96 (84%) patients demonstrated a good position and 18 (16%) an adequate position after TEE unblinding. An out-of-FO or dangerous position did not occur. A successful 3D map-guided TP was performed in 110 attempts (97%). Four attempts (3%) with adequate positions were aborted in order to seek a more convenient TP site. The median time from RA mapping until the end of the TP process was 13 (12-17) min. No TP-related complications occurred. Ninety-eight TP sites (85.1%) were in the central portion or in the inner loop of the FO.

CONCLUSION

A 3D map-guided TP is feasible and safe. It may assist to decrease radiation exposure and the need for TEE/ICE during left-sided catheter ablation procedures.

The presence of a large patent foramen ovale reduces acute and chronic success in atrial fibrillation ablation

PURPOSE

In this study, we analyzed PFO implications in atrial fibrillation (AF) ablation.

METHODS

Six hundred and twenty-five consecutive patients with AF undergoing PV isolation were included. We considered that a large and/or compliant PFO was present if the catheters advanced gently into the LA without puncturing the septum. Atrial tachyarrhythmias after the 3-month blanking period were classified as a recurrence.

RESULTS

Out of the 625 patients included, 36 (5.8%) were found to have PFO. No significant differences were observed in the clinical characteristics of patients with PFO compared with patients without PFO. Nevertheless, patients with PFO had lower acute success in PV isolation compared with patients without PFO (98.2% vs. 88.5%; p = 0.006) even after adjusting for age, sex, type of AF, LA area, cardiomyopathy, time from AF diagnosis to the ablation, and ablation technique (odds ratio: 0.1; 95% confidence interval (CI): 0.02-0.9; p = 0.039). In 546 patients followed more than 6 months, the recurrence rate of any atrial tachyarrhythmia after 18.6 ± 11.9 months was significantly higher in patients with PFO compared with patients without PFO (41.9 vs. 70%; p = 0.012). This difference remained significant after adjusting for age, sex, type of AF, LA area, cardiomyopathy, time from AF diagnosis to the ablation, and ablation technique (hazard ratio: 1.9; 95% CI: 1.1-3.3; p = 0.015).

CONCLUSIONS

The presence of a large and/or compliant PFO is an independent factor for PV isolation failure and arrhythmia recurrence rate after the ablation.

Metal interference alert guided septal approach with 3 catheter positions on intracardiac echocardiography for a near-zero fluoroscopy catheter ablation of atrial fibrillation

Background

Attempting to minimize radiation exposure during catheter ablation of atrial fibrillation (AF) for patients, operators and medical staffs should be performed. This study aimed to investigate the feasibility and safety of a metal interference alert guided septal approach using 3 intracardiac echocardiography viewing positions for near-zero fluoroscopy AF ablation procedures.

Methods/results

A total of 668 procedures among 608 consecutive patients with AF (67.2 ± 7.3 years, 408 males) who underwent catheter ablation were retrospectively evaluated and divided into 2 groups, near-zero group (n = 42) and conventional group (n = 595). In the near-zero group, a metal interference alert guided septal approach with 3 different catheter intracardiac echocardiography positions to minimize the fluoroscopy time was applied, and a left atrial access with 2 long sheaths from a single septal puncture without fluoroscopy was successfully achieved in 41 out of 42 cases. The total fluoroscopy time was significantly shorter in the near-zero group than that in the conventional group (0.5 ± 2.0 vs. 21.4 ± 12.9 min p < 0.0001). The total procedure time and time to the septal puncture were both significantly longer in the near-zero group than those in the conventional group (131.4 ± 40.2 vs. 116.6 ± 46.4p = 0.0453, 31.6 ± 9.2 vs. 19.9 ± 10.2 min, p < 0.0001), The ablation time did not differ between the 2 groups (Near-zero: 99.8 ± 41.0 vs. Conventional: 96.8 ± 44.3 min, p = 0.6663). There were no significant differences in the complication rate between the 2 groups (Near-zero: 0 vs. Conventional 14 case, p = 0.6151).

Conclusion

A metal interference alert guided septal approach using 3 intracardiac echocardiography viewing positions was feasible and safe for a near-zero fluoroscopy catheter ablation of AF.

Interatrial septum dissection and atrial wall hematoma following transseptal puncture: A systematic review of the literature

BACKGROUND

Interatrial septum (IAS) dissection due to transseptal puncture (TSP) is a rare, underreported complication of the procedure. Data on the mechanism, diagnosis, and management of this complication are lacking.

METHODS

We conducted a systematic review of all reported cases of IAS dissection with or without associated LA hematoma due to TSP, by thoroughly searching MEDLINE and EMBASE through May 2019.

RESULTS

After screening of n = 882 studies, eight studies with a total of 19 patients addressed the complication of IAS dissection and/or LA hematoma secondary to TSP. Median age was 63 years with a 1:1 male to female ratio. Ablation of atrial fibrillation was the most frequently reported procedure (84%). Diagnosis was established using fluoroscopy with contrast injection (58%), TEE (32%) or intracardiac echocardiography (5%). The mechanism identified involved puncture of the septum secundum portion of the IAS, leading to transient needle passage into the extracardiac space. In the majority of patients, the hematoma remained localized in the IAS and management was conservative with progressive resolution of the hematoma during follow-up (95%). Two patients (11%) required further intervention by either pericardiocentesis or surgical drainage due to hemodynamic instability.

CONCLUSIONS

IAS dissection with or without hematoma after TSP remains an underdiagnosed entity. The main mechanism involves lesion to the septum secundum portion of the IAS, resulting in needle passage into the extracardiac space and local bleeding. Although conservative management may be sufficient in the majority of cases, interventional cardiologists should be familiar with this complication and its diagnosis.

Prospective evaluation of iatrogenic atrial septal defect after cryoballoon or radiofrequency catheter ablation of atrial fibrillation-"EVITA" study

PURPOSE

Iatrogenic atrial septal defect (IASD) after catheter ablation (CA) for atrial fibrillation (AF) due to transseptal puncture (TSP) can occur. The aim of this prospective study was to describe the incidence of IASD and to detect any cerebrovascular accident (CVA) after radiofrequency (RF) and cryoballoon (CB) CA.

METHODS

Between July 2014 and September 2016, 94 patients (pts) (RF; 48, CB; 46, 30 (31.9%) women, mean age = 60 ± 9.7 years) with paroxysmal AF were enrolled who underwent CA procedure for the first time. During RF ablation a single (n = 30, 62.5%) or double (n = 18, 37.5%) TSP was performed. Transoesophageal echocardiography before the procedure and at the 3-month and 12-month follow-up (FU) was accomplished. During the FU period, we evaluated the occurrence of any postprocedural CVA.

RESULTS

At the 3-month FU, IASD was detected in 17/94 (18.1%) pts; in 9/48 (18.8%) pts in the RF while in 8/46 (17.4%) pts in the CB group (p = 0.866), all of them with left-to-right shunt. In the RF group, 6/30 (20%) pts with a single TSP while 3/18 (16.7%) pts in the double TSP group had IASD (p = 0.780). 14/17 (82.4%) IASDs showed high spontaneous closure rate at the 12-month FU. None of the pts died or suffered from CVA.

CONCLUSION

Persistent IASD can occur rather frequently following AF CA. No significant difference was observed between the RF and CB techniques concerning the presence of IASD at 3-month. IASDs showed a high spontaneous closure rate. No cerebral thromboembolic event was observed in the 12-month FU period.

Transvenous Treatment of Carotid Aneurysms Through Transseptal Access

BACKGROUND

Transseptal puncture has been widely used by cardiologists to reach the left side of the heart through a transvenous access. Rarely, it also can be used to pass into the supra-aortic arteries from the venous side when conventional transarterial access pathways (transfemoral, transradial/brachial routes, or direct carotid puncture) are likely to fail.

CASE DESCRIPTION

We report 2 cases of transvenous femoral access followed by transseptal access to aorta to treat dissecting carotid artery aneurysms at the level of the skull base with flow diverters. In one case, multiple cervical arterial bypass operations and in the other a rare anomaly of the aortic arch precluded endovascular treatment through conventional routes.

CONCLUSIONS

Transvenous-transseptal access enabled treatment of both cases easily and without complications. On follow-up computed tomography angiograms, both flow diverters were patent, there were no residual aneurysms, and no neurologic or cardiac adverse events in either patient.

Transseptal Access to the Left Atrium: Tips and Tricks to Keep it Safe Derived from Single Operator Experience and Review of the Literature

BACKGROUND

Transseptal puncture (TSP) remains a demanding procedural step in accessing the left atrium with inherent risks and safety concerns, mostly related to cardiac tamponade.

OBJECTIVE

Based on our own experience with 249 TSP procedures and in-depth literature review, we present our results and offer several tips and tricks that may render TSP successful and safe.

METHODS

This prospective study comprised 249 consecutive patients (146 men), aged 41.6±17.4 years, undergoing TSP by a single operator for ablation of a variety of arrhythmias, mostly related to left accessory pathways (n=145) or left atrial tachycardias (n=33) and more recently, atrial fibrillation (n=70). TSP was guided by fluoroscopy alone in all patients without the use of echocardiography imaging. In addition, an extensive literature review of TSP-related topics was carried out in PubMed, Scopus and Google Scholar.

RESULTS

Among 249 patients, 33 patients were children or young adolescents (aged 7-18 years); 14 patients were undergoing a repeat procedure. Patients with a manifest accessory pathway were the youngest (mean age 33.7±15.9) and patients with atrial fibrillation the oldest (mean age 56.0±10.8 years). A successful TSP was accomplished in 247 patients (99.2%). Two (0.8%) procedures were complicated by cardiac tamponade managed successfully with pericardiocentesis or surgical drainage. Review of the literature revealed no systematic reviews and meta-analyses of TSP studies; however, several patient series have documented that fluoroscopy-guided TSP, with various modifications in the technique employed in the present series, have been effective in 95-100% of the cases with a complication rate ranging from 0.0% to 6.7%, albeit with a mortality rate of 0.018%- 0.2%. Echo imaging techniques were employed in cases with difficult TSP.

CONCLUSION

Employing a standardized protocol with use of fluoroscopy alone minimized serious complications to 0.8% (2 patients) among 249 consecutive patients undergoing TSP for ablation of a variety of cardiac arrhythmias. Based on this single-operator experience and review of the literature, a list of practical tips and tricks is provided for a successful and safe procedure, reserving the more expensive and patient inconveniencing echo-imaging techniques for difficult or failed cases.

Fluoroscopy-free AF ablation using transesophageal echocardiography and electroanatomical mapping technology

PURPOSE

Guidelines recommend that radiation exposure during AF catheter ablation procedures should be 'as low as reasonably achievable' (ALARA), particularly since many patients may have multiple procedures. Consequently, avoiding radiation exposure altogether must, if safe to do so, be the ultimate goal. The primary objective was to determine the feasibility and efficacy of fluoroscopy-free AF ablation compared to the fluoroscopy-assisted procedure.

METHODS

Patients underwent AF ablation using commercially available technology with no routine pre-procedural imaging. The use of non-fluoroscopic imaging/mapping technologies permitted us to initially reduce x-ray exposure before eliminating its use altogether. This evolution of our practice proceeded in two stages: a 9-month period of optimising our fluoroscopy-free ablation protocol followed by a 9-month period during which we set out to complete the whole procedure routinely without fluoroscopy. We describe the protocol developed and report salient endpoints, such as complications, procedure times, patient experience, and procedural success rates.

RESULTS

During the study period, fluoroscopy-free AF ablation was attempted in 69 patients: 24 in the 9-month 'development phase' and 45 in the 'implementation phase'. During the development phase, 13 of 24 patients (54%) were treated without the use of fluoroscopy. In the implementation phase, 45 patients underwent AF ablation of which 42 (93.3%) were fluoroscopy-free. A detailed description is given of the three cases in which fluoroscopy had to be used despite an intention not to.

CONCLUSIONS

Fluoroscopy-free complex ablation procedures for the treatment of atrial fibrillation are safe and feasible in most patients.

Novel Solutions Applied in Transseptal Puncture: A Systematic Review

Access to the left atrium is required for several minimally invasive cardiac interventions in the left heart. For this purpose, transseptal puncture (TSP) technique is often performed, perforating the atrial septum under fluoroscopic or/and ultrasound imaging guidance. Although this approach has been used for many years, complications/failures are not uncommon mainly in patients with abnormal atrial anatomy and repeated TSP. Thus, this study presents an overview of methods and techniques that have been proposed to increase the safety and feasibility of the TSP. A systematic review of literature was conducted through the analysis of the articles published between 2008 and 2015. The search was performed in PubMed, Scopus, and ISI Web of Knowledge using the expression “transseptal puncture.” A total of 354 articles were retrieved from the databases, and 64 articles were selected for this review. Moreover, these 64 articles were divided into four categories, namely: (1) incidence studies, (2) intraprocedural guidance techniques, (3) preprocedural planning methods, and (4) surgical instruments. A total of 36 articles focused on incidence studies, 24 articles suggested novel intraprocedural guidance techniques, 5 works focused on preprocedural planning strategies, and 21 works proposed surgical instruments. The novel 3D guidance techniques, radio-frequency surgical instruments, and pre-interventional planning approaches showed potential to overcome the main procedural limitations/complications, through the reduction of the intervention time, radiation, number of failures, and complications.

Suction catheter for enhanced control and accuracy of transseptal access

AIMS

Percutaneous structural heart therapies, such as mitral value repair, require site-specific transseptal access (TSA). This can be challenging for interventional cardiologists. We describe a TSA catheter (TSAC) that utilises suction for enhanced control and puncture accuracy. Here, we aim to evaluate the safety and efficacy of the device.

METHODS AND RESULTS

Ex vivo interatrial septum preparations were dissected from swine (n=8) and diseased human hearts (n=6) to quantify TSAC suction and needle puncture force. TSAC suction was 6.5-fold greater than the opposing needle puncture force, and thus provides sufficient stabilisation for punctures. The safety and efficacy of TSAC was evaluated in a chronic mitral regurgitation swine model (n=10) and compared to a conventional TSA device. MR was induced by disrupting one to three mitral chordae tendineae, and the progression of heart disease was followed for three weeks. During device testing, procedure time and fluoroscopy exposure were not statistically different between devices. TSAC reduced septal displacement from 8.7±0.30 mm to 3.60±0.19 mm (p<0.05) and improved puncture accuracy 1.75-fold.

CONCLUSIONS

TSAC provides controlled TSA and improves puncture accuracy, while maintaining procedure time and workflow. These findings provide a strong rationale for a first-in-man study to demonstrate the clinical utility of the device.

[Transseptal puncture after device closure of patent foramen ovale: Is it feasible?]

CASE REPORT

The case of a 40-year-old woman with paroxysmal symptomatic atrial fibrillation and implanted occluder of a patent foramen ovale (PFO; AMPLATZER™ Septal Occluder, St. Jude Medical) is reported. Due to the symptomic atrial fibrillation, pulmonary vein isolation was planned.

METHODS

Under transesophageal, echocardiographic control the transseptal puncture was performed posterior inferior of the occluder without any complications. The pulmonary vein was successfully isolatedusing radiofrequency energy.

CONCLUSION

This case demonstrates that transseptal puncture in pulmonary vein isolation with an inserted PFO occluder under additional transesophageal, echocardiographic monitoring is safe and feasible.

Fluoroscopy-Free Pulmonary Vein Isolation in Patients with Atrial Fibrillation and a Patent Foramen Ovale Using Solely an Electroanatomic Mapping System

Introduction

The advent of electroanatomical mapping (EAM) systems for pulmonary vein isolation (PVI) has dramatically decreased radiation exposure. However, the need for some fluoroscopy remains for obtaining left atrial (LA) access. The aim was to test the feasibility of fluoroscopy-free PVI in patients with atrial fibrillation (AF) and a patent foramen ovale (PFO) guided solely by an EAM system.

Methods

Consecutive patients with AF undergoing PVI and documented PFO were studied. An EAM-guided approach without fluoroscopy and ultrasound was used. After completing the map of the right atrium, the superior vena cava and the coronary sinus, a catheter pull-down to the PFO was performed allowing LA access. The map of the LA and subsequent PVI was also performed without fluoroscopy.

Results

30 patients [age 61±12 years, 73% male, ejection fraction 0.64 (0.53–0.65), LA size in parasternal long axis 38±7 mm] undergoing PVI were included. The time required for right atrial mapping including transseptal crossing was 9±4 minutes. Total procedure time was 127±37 minutes. Fluoroscopy-free PVI was feasible in 26/30 (87%) patients. In four patients, fluoroscopy was needed to access (n = 3) or to re-access (n = 1) the LA. In these four patients, total fluoroscopy time was 5±3 min and the DAP was 14.9±13.4 Gy*cm². Single-procedure success rate was 80% (24/30) after a median follow-up of 12 months.

Conclusion

In patients with a documented PFO, completely fluoroscopy-free PVI is feasible in the vast majority of cases.

Fluoroscopy-free recrossing of the interatrial septum during left atrial ablation procedures

AIM

The purpose of this is to evaluate the safety and feasibility of recrossing the interatrial septum in case of inadvertent loss of or need for repeated left atrial access using a simple electroanatomical landmark without the use of fluoroscopy.

METHODS

Twenty-five consecutive patients undergoing pulmonary vein isolation (PVI) for paroxysmal (n = 12) or persistent (n = 13) atrial fibrillation ablation were included. All procedures were performed using an electroanatomical mapping system (Carto 3, Biosense Webster, Diamond Bar, USA). After fluoroscopy-guided double transseptal puncture and fast anatomical mapping of the left atrium, a reconstruction of the transseptal access was created by retracting the mapping catheter into the sheath to the level of the inferior vena cava. After completing the left sided ablation, both sheaths and catheters were withdrawn to the inferior vena cava. Recrossing was then attempted by fellows (EF) and experienced operators (EO) using the reconstruction of the transseptal access in a standard right anterior oblique (RAO) and left anterior oblique (LAO) projection without the use of fluoroscopy.

RESULTS

Using the described technique, EP fellows and experienced operators could recross the interatrial septum without fluoroscopy in all patients. Median time needed for recrossing was 14 s (interquartile range (IQR) 7-20). Median recrossing times did not differ significantly between EF and EO (14 (IQR 8-26.5 s) versus 12 (IQR 6.5-17.5 s), p = 0.26). In five (20 %) procedures, recrossing was necessary during the procedure after intermittent mapping of the right atrium or inadvertent catheter dislodgment.

CONCLUSION

Adding a simple and fast anatomical reconstruction of the transseptal access to the standard left atrial mapping procedure allows for easy and fluoroscopy-free recrossing of the interatrial septum during atrial fibrillation ablation and further reduces radiation exposure.