Transesophageal Echocardiography Improves Precision in Transseptal Puncture Compared to Fluoroscopy in Left Atrial Electrophysiological Procedures

Background: Complex arrhythmias often arise from the left side of the heart, necessitating established electrophysiological (EP) procedures like 3D-mapping-assisted radiofrequency (RF) ablations or pulmonary vein isolation (PVI). These procedures typically require transseptal access, emphasizing the critical role of achieving an optimal catheter position through a precise transseptal puncture (TSP). Commonly employed imaging methods for TSP guidance include fluoroscopy and interventional echocardiography. Despite their routine use, there is limited evidence on which imaging modality offers superior catheter positioning for EP procedures, and safety concerns regarding transseptal punctures with imaging remain underexplored. This study aims to systematically evaluate the feasibility, safety, and accuracy of echo-guided TSP compared to fluoroscopy-guided TSP. Methods: In this prospective study, 150 consecutive patients undergoing left atrial EP procedures were enrolled between October 2023 and February 2024 at the Ulm University Heart Center. Following optimal fluoroscopy-guided transseptal needle positioning at the interatrial septum, the catheter placement was further verified using transesophageal echocardiography (TEE). Adjustments were made in cases of suboptimal needle positioning observed in TEE. The fluoroscopically achieved septal positions were categorized based on TEE images as optimal, suboptimal, poor, or dangerous. Results: Among the 150 patients included (58.0% male), fluoroscopy achieved optimal, suboptimal, and poor/dangerous positions in 32.7%, 43.3%, and 24.0%, respectively. After TEE-guided adjustments, optimal and suboptimal positions were achieved in 59.3% and 40.7% of patients, respectively. No instances of poor or dangerous transseptal needle positions were observed under TEE guidance. Conclusions: TEE-guided TSP emerges as a feasible, more accurate, and safer imaging method for transseptal punctures in EP procedures.

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.

Rotational Angiography Based Three-Dimensional Left Atrial Reconstruction: A New Approach for Transseptal Puncture

AIM

Rotational angiography is a well-known method for the three-dimensional (3-D) reconstruction of left atrium and pulmonary veins during left-sided atrial arrhythmia ablation procedures. In our study, we aimed to review our experience in transseptal puncture (TSP) using 3-D rotational angiography.

METHODS

We included a total of 271 patients who underwent atrial fibrillation ablation using cryoballoon. Rotational angiography was performed to get the three-dimensional left atrial and pulmonary vein reconstructions using cardiac C-arm computed tomography. The image reconstruction was made using the DynaCT Cardiac software (Siemens, Erlangen, Germany).

RESULTS

The mean age of the study population was 61 ± 10 years. The indications for left atrial arrhythmia ablation were paroxysmal AF in 140 patients (52%) and persistent AF patients in 131 (48%) patients. The success rate of TSP using only rotational guidance was (264/271 patients, 97.4%). In the remaining seven patients, transesophageal guidance was used after the initial attempt due to thick interatrial septum in five patients and difficult TSP due to abnormal anatomy and mild pericardial effusion in the remaining two patients. Mean fluoroscopy dosage of the rotational angiography was 4896.4 ± 825.3 μGym(2). The mean time beginning from femoral vein puncture to TSP was 12.3 ± 5.5 min.

CONCLUSION

TSP guided by rotational angiography is a safe and effective method. Our results indicate that integration of rotational angiographic images into the real-time fluoroscopy can guide the TSP during the procedure.

Modified mallampati classification in determining the success of unsedated transesophageal echocardiography procedure in patients with heart disease: simple but efficient

Background

The transesophageal echocardiograhpy (TEE) has been studied worldwide. However, identifying additional factors on top of operator's experience and patient's cooperation which could influence the success of the procedure in unsedated patients with heart disease  is not well documented.

Methods

Under the cross-sectional descriptive design, 85 target patients were fulfilling the criteria: being Thai national at the age of at least 20-year-old, being performed TEE by the study participant’s cardiologists, being able to communicate verbally. Seven outcomes were recorded, including gag reflex, insertion attempt, insertion time, vital signs (heart rate, oxygen saturation and mean arterial blood pressure), visible blood on TEE probe tip, and oropharyngeal pain at 1 h and 24-h.

Results

There were 85 eligible patients during June 2012 to June 2013. The major participants were male (46, 54 %) and the mean age was 51.2 ± 12.5 years. The MMC class III was mostly found (33, 38.80 %). TEE probe insertion time and gag reflex were indicated statistical significance (P < 0.05). Linear regression revealed that MMC class III (b 3.718; SD ± 1.077; P = 0.001) and class IV (b 5.15; SD ± 1.286; P = 0.000) were statistically associated with TEE probe insertion time, whereas MMC class II was no statistically significant (b 2.348; SD ± 1.405; P = 0.099) according to constant value in MMC class I (5.318 s). Similarly, logistic regression indicated that the patients with high grade MMC were more likely to have gagging than the low grade MMC patients (MMC 2 OR 0.567, 95 % CI 0.09–3.42, P = 0.536; MMC 3 OR 5.231, 95 % CI 1.55–17.67, P = 0.008; MMC 4 OR 3.4, 95 % CI 0.84–13.76, P = 0.086).

Conclusions

Modified Mallampati Classification is one of determining factors in the success of unsedated TEE procedure in patients with heart disease, especially for assessment of gagging and successful TEE probe insertion time.

Optical coherence tomography assessment of a PLGA-polymer with electro-grafting base layer versus a PLA-polymer sirolimus-eluting stent at three-month follow-up: the BuMA-OCT randomised trial

AIMS

To compare stent strut coverage using optical coherence tomography (OCT) at three-month follow-up between a PLGA-polymer with electro-grafting base layer sirolimus-eluting stent (SES) (BuMA) and a PLA-polymer SES (EXCEL).

METHODS AND RESULTS

This prospective, single-centre, non-inferiority randomised BuMA-OCT trial enrolled patients with de novo coronary artery lesions, treated with either the BuMA or the EXCEL stent. The study primary endpoint was OCT-evaluated stent strut coverage at three months. Secondary endpoints were neointimal thickness of stent struts, and incomplete stent apposition evaluated with OCT. A total of 80 patients were randomly assigned to receive the BuMA (n=40) or the EXCEL (n=40) stent. In OCT follow-up (achieved in 86.3% of cases: BuMA, n=33; EXCEL, n=36), the percentage of stent strut coverage was significantly higher in the BuMA vs. the EXCEL group (strut level: 94.2% vs. 90.0%, p<0.01; p(non-inferiority)<0.0001; p(superiority) <0.0001), while the proportion of malapposed struts (strut level: 1.28% vs. 1.80%, p=0.51) and the mean neointimal thickness (strut level: 0.07±0.03 mm vs. 0.06±0.02 mm, p=0.31) were similar. Rates of myocardial infarction (periprocedural non-Q-wave, 7.5% vs. 7.5%, p=1.00) and target lesion failure (7.5% vs. 7.5%, p=1.00) were similar between groups, with no cardiac death or stent thrombosis.

CONCLUSIONS

In the BuMA-OCT randomised trial, the novel BuMA PLGA-polymer with electro-grafting base layer SES was superior to the EXCEL PLA-polymer SES in the primary endpoint of stent strut coverage at three-month follow-up.

Reduction of Iatrogenic Atrial Septal Defects with an Anterior and Inferior Transseptal Puncture Site when Operating the Cryoballoon Ablation Catheter

The cryoballoon catheter ablates atrial fibrillation (AF) triggers in the left atrium (LA) and pulmonary veins (PVs) via transseptal access. The typical transseptal puncture site is the fossa ovalis (FO) - the atrial septum's thinnest section. A potentially beneficial transseptal site, for the cryoballoon, is near the inferior limbus (IL). This study examines an alternative transseptal site near the IL, which may decrease the frequency of acute iatrogenic atrial septal defect (IASD). Also, the study evaluates the acute pulmonary vein isolation (PVI) success rate utilizing the IL location. 200 patients were evaluated by retrospective chart review for acute PVI success rate with an IL transseptal site. An additional 128 IL transseptal patients were compared to 45 FO transseptal patients by performing Doppler intracardiac echocardiography (ICE) post-ablation to assess transseptal flow after removal of the transseptal sheath. After sheath removal and by Doppler ICE imaging, 42 of 128 (33%) IL transseptal patients demonstrated acute transseptal flow, while 45 of 45 (100%) FO transseptal puncture patients had acute transseptal flow. The difference in acute transseptal flow detection between FO and IL sites was statistically significant (P <0.0001). Furthermore, 186 of 200 patients (with an IL transseptal puncture) did not need additional ablation(s) and had achieved an acute PVI by a "cryoballoon only" technique. An IL transseptal puncture site for cryoballoon AF ablations is an effective location to mediate PVI at all four PVs. Additionally, an IL transseptal location can lower the incidence of acute transseptal flow by Doppler ICE when compared to the FO. Potentially, the IL transseptal site may reduce later IASD complications post-cryoballoon procedures.

Role of Intracardiac echocardiography in Atrial Fibrillation Ablation

In the recent years, several new evidences support catheter-based ablation as a treatment modality of atrial fibrillation (AF). Based on a plenty of different applications, intracardiac echocardiography (ICE) is now a well-established technology in complex electrophysiological procedures, in particular in AF ablation. ICE contributes to improve the efficacy and safety of such procedures defining the anatomical structures involved in ablation procedures and monitoring in real time possible complications. In particular ICE allows: a correct identification of the endocardial structures; a guidance of transseptal puncture; an assessment of accurate placement of the circular mapping catheter; an indirect evaluation of evolving lesions during radiofrequency (RF) energy delivery via visualization of micro and macrobubbles tissue heating; assessment of catheter contact with cardiac tissues. Recently, also the feasibility of the integration of electroanatomical mapping (EAM) and intracardiac echocardiography has been demonstrated, combining accurate real time anatomical information with electroanatomical data. As a matter of fact, different techniques and ablation strategies have been developed throughout the years. In the setting of balloon-based ablation systems, recently adopted by an increasing number of centers, ICE might have a role in the choice of appropriate balloon size and to confirm accurate occlusion of pulmonary veins. Furthermore, in the era of minimally fluoroscopic ablation, ICE has successfully provided a contribute in reducing fluoroscopy time. The purpose of this review is to summarize the current applications of ICE in catheter based ablation strategies of atrial fibrillation, focusing-on electronically phased-array ICE.

Complications from catheter ablation of atrial fibrillation: a systematic review

Atrial fibrillation (AF) is the most common arrhythmia requiring treatment that is encountered in clinical practice. Recent advances in the understanding of underlying mechanisms of AF have led to the increased use of catheter ablation (CA) as a treatment modality for paroxysmal, persistent, or long-standing persistent AF in patients with symptomatic AF despite treatment with antiarrhythmic medications. Because of the complexity in technique and anatomic location of the ablation sites, it is not surprising that CA of AF is associated with a greater risk of procedural complications compared with simpler cardiac ablation procedures. Major and minor complications, including life-threatening complications, have been described and quantified. This systematic review describes the potential risks of CA that have been reported over a period and provides insights into the evolving strategies to minimize these complications, thus making CA techniques safer and potentially more efficacious for AF.

Intracardiac echocardiography: clinical utility and application

Intracardiac echocardiography (ICE) broadens the spectrum of available echocardiographic techniques and provides the operator direct visualization of cardiac structures in real time. ICE has clear advantages over fluoroscopy, transthoracic echocardiography, and transesophageal echocardiography as the imaging modality of choice in the cardiac catheterization and electrophysiological laboratories. With the development of steerable phased array catheters with low frequency and Doppler qualities, there is marked improvement in visualization of left-sided structures from the right heart. Appropriate utilization of ICE is likely to maximize safety and efficacy of complex interventional procedures and may improve patient outcomes. Future advances in ICE imaging will further improve the ease of device guidance and, in combination with new imaging modalities, could dramatically improve other applications of echocardiography which may result in improved patient outcomes. This review describes the technical evolution of ICE, the use of ICE in guiding percutaneous interventional procedures and possible future applications of ICE in the ever-growing field of interventional cardiology.

Acute pericardial effusion following atrial fibrillation ablation: characteristics and relationship with arrhythmia recurrences

BACKGROUND

Pericardial effusion (PE) can occur during or after atrial fibrillation (AF) ablation, and may induce atrial arrhythmia.

AIM

To characterize the impact of PE on arrhythmia recurrences following AF ablation.

METHODS

Patients referred for a first radiofrequency AF ablation were studied prospectively. Transthoracic echocardiography was performed before and 24h after the procedure. If PE was present, transthoracic echocardiography was repeated at 1 month to evaluate PE evolution. Early arrhythmia recurrences (EARs) were defined as any arrhythmia documented within 1 month of the procedure.

RESULTS

PE was diagnosed in 18/81 patients (22%); and was present in significantly more patients with persistent versus paroxysmal AF (14/40 [35%] vs 4/41 [10%]; P=0.008). PEs were mild (mean 6 ± 3mm), mainly asymptomatic (89%), and none required pericardiocentesis. Early and late arrhythmia recurrences were present in 25/81 (31%) and 29/81 (36%), respectively. The incidence of PE was significantly higher among patients with EARs versus those without (12/25 [48%] vs 6/56 [11%]; P=0.0004). By multivariable analysis, PE and duration in AF were the two independent predictors of EARs. PE incidence was similar in patients with and without late arrhythmia recurrences. At 1 month, no patients had PE on transthoracic echocardiography.

CONCLUSION

PE following radiofrequency AF ablation is frequent, particularly following persistent AF ablation. This effusion is generally mild, mainly asymptomatic, and independently associated with EARs.

Complications of atrial fibrillation ablation: when prevention is better than cure

As atrial fibrillation ablation is becoming increasingly popular in many cardiac electrophysiological laboratories around the world, preventing, avoiding, or treating procedure-related complications is of utmost importance. In our review of the literature regarding this issue, we addressed in detail all the potential collateral and undesired effects associated to this intervention.