Transseptal Left Heart Catheterization

Atrial Transseptal Catheterisation: Challenging Scenarios and Techniques to Overcome Them

Atrial transseptal catheterisation is a fundamental skill of any interventional electrophysiologist. In this review, various scenarios that pose unique challenges to atrial transseptal catheterisation are discussed. These scenarios include post-surgical or congenital malformations of the interatrial septum, presence of interatrial septal closure devices, absent or obstructed inferior vena cava and complex congenital heart disease after palliative surgery. Transseptal catheterisation in all of the above situations is feasible and can be performed safely with the aid of dedicated tools and specific techniques.

Transseptal puncture: Review of anatomy, techniques, complications and challenges, a critical view

Transseptal puncture (TSP) was initially described to gain access to the left heart for hemodynamic assessment. Continuous evolution from its origins allows interventionists to perform a myriad of procedures that otherwise would be impossible to accomplish. In the recent years, the number of procedures in cardiology that require TSP has grown exponentially. Namely, transcatheter mitral valve repair and replacement, pulmonary vein isolation and left atrium appendage occlusion. In skilled hands, it is a safe and straightforward procedure; however, a lack of knowledge of the materials, anatomy of the interatrial septum and the technique can be met with life-threatening complications. Therefore, it is imperative that interventional cardiologists master this technique to successfully overcome these obstacles and ensure clinical outcomes in patients requiring TSP. The purpose of the following review is to critically analyze the available evidence regarding TSP, provide a step-by-step approach to the technique, the available materials and tips and tricks to overcome difficulties and manage complications.

Transseptal Puncture Learning Curve for Transcatheter Edge-to-Edge Mitral Valve Repair

OBJECTIVE

This study examined the learning curve for transseptal puncture (TSP) during transcatheter edge-to-edge mitral valve repair (TEER) performed by a dedicated mitral valve structural heart team. Effective TSP is mandatory for TEER but can be time-consuming and associated with complications including pericardial effusion and cardiac tamponade.

METHODS

TSP was performed on 107 consecutive patients (76 ± 1 years, 52% male) undergoing TEER between 2014 and 2019. TSP was performed by each structural heart team member (1 cardiologist, 2 cardiac surgeons) on a rotating case-by-case basis. No team member had prior independent TSP experience. Data collected included total procedure time, TSP time (time elapsed between procedure start and septal crossing), and number of TSP attempts before successful puncture. Cumulative sum (CUSUM) of deviations from the mean across sequential cases were used to examine learning curves.

RESULTS

Median total procedure time was 107 min, and the median TSP time was 14 min. Greater case number was significantly associated with both lower TSP time (r _s = -0.22, P = 0.022) and lower total procedure time (r _s = -0.29, P = 0.003). The majority of patients required only 1 TSP attempt (79%). There was a significant quadratic relationship between case number and the CUSUM for TSP time, with the learning curve peaking at 49 cases.

CONCLUSIONS

TSP for TEER has a substantial learning curve, requiring >50 cases to achieve acceptable efficiency. Even once proficiency is demonstrated, TSP remains a time-consuming component of TEER. Improvements in transseptal access technology may significantly decrease the time needed to master TSP and may improve the safety and precision of the procedure.

Safety of Transseptal Puncture for Access to the Left Atrium in Infants and Children

Transseptal puncture (TSP) is a standard procedure to obtain access to the left heart. However, data on TSP in infants and children particularly with congenital heart defects (CHD) is sparse. Safety and efficacy of TSP in infants and children < 18 years with normal cardiac anatomy and with CHD were assessed. 327 TSP were performed in a total of 300 individuals < 18 years from 10/2002 to 09/2018 in our tertiary pediatric referral center. Median age at TSP was 11.9 years (IQR 7.8-15; range: first day of life to 17.9 years). 13 subjects were < 1 year. Median body weight was 43.8 kg (IQR 26.9-60; range: 1.8-121 kg). CHD was present in 28/327 (8.6%) procedures. TSP could be successfully performed in 323/327 (98.8%) procedures and was abandoned in 4 procedures due to imminent or incurred complications. Major complications occurred in 4 patients. 3 of these 4 subjects were ≤ 1 year of age and required TSP for enlargement of a restrictive atrial septal defect in complex CHD. Two of these babies deceased within 48 h after TSP attempt. The third baby needed urgent surgery in the cath lab. Pericardial effusion requiring drainage was noted in the forth patient (> 1 year) who was discharged well later. Minor complications emerged in 5 patients. The youngest of these individuals (0.3 years, 5.8 kg) developed small pericardial effusion after anterograde ballon valvuloplasty for critical aortic stenosis. The remaining 4/5 patients developed small pericardial effusion after ablation of a left-sided accessory atrioventricular pathway (6.1-12.2 years, 15.6-34.0 kg). TSP for access to the left heart was safe and effective in children and adolescents > 1 year of age. However, TSP was a high-risk procedure in small infants with a restrictive interatrial septum with need for enlargement of interatrial communication.

Pericardial tamponade as a complication of invasive cardiac procedures: a review of the literature

Cardiac tamponade (CT) is a rare but often life-threatening complication after invasive cardiac procedures. Some procedures favor CT. Furthermore, the incidence depends on patients’ comorbidities, sex and age and operators’ skills. In this paper we review studies and meta-analyses concerning the rate of iatrogenic CT. We define the risk factors of CT and show concise characteristics for each invasive cardiac procedure separately. According to our analysis CT occurs especially after procedures requiring transseptal puncture or perioperative anticoagulation. The overall rate of CT after such procedures varies among published studies from 0.089% to 4.8%. For this purpose we searched the PubMed database for clinical studies published up to December 2018. We included only those studies in which a defined minimum of procedures were performed (1000 for atrial fibrillation ablation, 6000 for percutaneous coronary intervention, 900 for permanent heart rhythm devices, 90 for left atrial appendage closure, 300 for transcatheter aortic valve implantation and percutaneous mitral valve repair with the Mitra-Clip system). The search was structured around the key words and variants of these terms. In addition, secondary source documents were identified by manual review of reference lists, review articles and guidelines. The search was limited to humans and adults (18+ years).

Distances between transseptal puncture site and anatomical landmarks

The aim of the study was to provide quantitative data and to look for new landmarks useful during transseptal puncture (TSP) using a fluoroscopy-guided approach. METHODS AND RESULTS: A total of 104 patients at mean age 57 ± 12 years, of whom 92% underwent pulmonary vein isolation, were analysed. Before TSP catheters were placed in the coronary sinus (CS) and His bundle region. A guidewire running from femoral vein through great veins was left loose in superior vena cava. Before TSP X-ray images were taken in right anterior oblique (RAO) 45° and RAO 53° projections. Locations posterior to TSP site in RAO were described with negative values and those anterior with positive values. The measured distances in millimeters were as follows: (a) between TSP site and posterior atrial wall (RAO 45 = -21 ± 7 mm; RAO 53 = -19 ± 6 mm (b) between TSP site and free guidewire (RAO 45 = -5 ± 4 mm, RAO 53 = -3 ± 4 mm (c) between TSP site and CS ostium (RAO 45 = 9 ± 6 mm; RAO 53 = 8 ± 5 mm (d) between TSP site and His region (RAO 45 = 29 ± 8 mm; RAO 53 = 30 ± 8 mm). We observed correlations between measured distances and age, body mass index and sizes of cardiac chambers. The distance between TSP site and the line projected by the guidewire running between great veins, measured in mid-RAO projections, was very small. CONCLUSION: The distances between TSP site and standard anatomical landmarks used during TSP vary with regard to age, physique and cardiac chamber dimensions. TSP site, as assessed in mid RAO, is in direct vicinity to the line projected by a guidewire running between the great veins.

A novel technique for performing transseptal puncture guided by a non-fluoroscopic 3D mapping system

BACKGROUND

Transseptal puncture (TSP) is commonly performed under fluoroscopic guidance in left atrial ablation procedures. This exposes patients and healthcare professionals to deleterious ionizing radiation. We describe a novel technique for performing TSP non-fluoroscopically using a three-dimensional (3D) mapping system only. The safety and efficacy of this technique is compared to traditional fluoroscopy guided TSP.

METHODS

Retrospective, single-center study of patients undergoing TSP for left atrial ablation. Those undergoing TSP using 3D mapping system alone (nonfluoroscopy group) were compared to those undergoing fluoroscopic guided TSP (Fluoroscopy group). Clinical, procedural data and complications were analyzed from a prospective registry.

RESULTS

Twenty patients (32 TSPs) in the nonfluoroscopy (NF) group were compared to 14 patients (25 TSPs) in fluoroscopy (F) group. TSP success rates were similar across the groups (88% vs 96% in the NF and F groups, P = 0.97). In the NF group, there was one cardiac tamponade, two unsuccessful TSPs (previous cardiac surgery-required TOE guided TSP), and one patient required fluoroscopy on a background of CRTD device to avoid lead displacement. The mean fluoroscopy time and dose were significantly lower in the nonfluoroscopy group (0.75  ±  0.50 vs 5.32 ± 3.23 min, P  <  0.001; 92.5 ± 60.7 vs 394.3 ± 182.7 cGy/cm² , P < 0.001).

CONCLUSION

Our study shows that TSPs can be performed safely and effectively using this non-fluoroscopic novel technique in a select group of patients. Radiation exposure is reduced significantly without compromising patient safety. Larger studies are required to substantiate these results. Patients with cardiac implantable devices and previous cardiac surgery may pose a challenge to using this technique.

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.

Through-needle all-optical ultrasound imaging in vivo: a preclinical swine study

High-frequency ultrasound imaging can provide exquisite visualizations of tissue to guide minimally invasive procedures. Here, we demonstrate that an all-optical ultrasound transducer, through which light guided by optical fibers is used to generate and receive ultrasound, is suitable for real-time invasive medical imaging in vivo. Broad-bandwidth ultrasound generation was achieved through the photoacoustic excitation of a multiwalled carbon nanotube-polydimethylsiloxane composite coating on the distal end of a 300-μm multi-mode optical fiber by a pulsed laser. The interrogation of a high-finesse Fabry-Pérot cavity on a single-mode optical fiber by a wavelength-tunable continuous-wave laser was applied for ultrasound reception. This transducer was integrated within a custom inner transseptal needle (diameter 1.08 mm; length 78 cm) that included a metallic septum to acoustically isolate the two optical fibers. The use of this needle within the beating heart of a pig provided unprecedented real-time views (50 Hz scan rate) of cardiac tissue (depth: 2.5 cm; axial resolution: 64 μm) and revealed the critical anatomical structures required to safely perform a transseptal crossing: the right and left atrial walls, the right atrial appendage, and the limbus fossae ovalis. This new paradigm will allow ultrasound imaging to be integrated into a broad range of minimally invasive devices in different clinical contexts.

Transseptal Techniques for Emerging Structural Heart Interventions

The development of new transseptal transcatheter interventions for patients with structural heart disease is fueling increasing interest in transseptal puncture techniques. The authors review contemporary transseptal puncture indications and techniques and provide a step-by-step approach to challenging transseptal access and procedural complications.

Transseptal puncture - Review of anatomy, techniques, complications and challenges

In recent years, the transseptal puncture approach has enabled passage of increasingly large and complex devices into the left atrium. Traditional tools remain effective in creating and dilating the initial puncture, with an acceptable safety profile. Even for skilled operators, the procedure is technically demanding and requires sound understanding of atrial anatomy. Intracardiac echocardiography is useful in cases of previous septal repair, poorly defined fossa ovalis anatomy or when considering patent foramen ovale portal crossing. Iatrogenic atrial septal defect (iASD) is the most commonly encountered long-term complication and there is increasing evidence that larger devices are leading to symptomatic defects. The size of the sheath crossing the septum is the strongest predictor of iASD formation but other factors such as longer procedure times, significant catheter manipulation and high pulmonary pressures also contribute. Transcatheter mitral valve repair involves the use of large 22 Fr catheters which carry alarmingly high rates of defect persistence with precipitation of symptoms and possible influence on mortality. Long-term follow up data, particularly beyond the 12-month period are lacking and resultantly, evidence to guide management is sparse. Refinements of conventional instruments, as well as innovations to puncture the septum without mechanical pressure, herald a progressively safer future for the transseptal technique.

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.

Transseptal puncture by CTP-2 method: Results from cardiac computed tomography analysis and clinical application

The current used parameters for transseptal puncture (TSP) under fluoroscopic guidance is from left atriography and need to be verified by precise anatomic measurement. From February 2009 to July 2013, consecutive patients who received computed tomography (CT) were included. Landmarks and parameters were preliminary studied by right atriography, and further evaluated on the CT images of 1001 patients. A method (CTP-2) was proposed for guiding TSP. In right anterior oblique 45° view, the CTP-2 method was defined by points C, T, and P, and 2 areas: point C is in coronary sinus; point T is at a distance of dCT (usually 1.5 ± 0.2 vertebral height) over point C; then point P, the optimal puncture site, was located at 0.5 ± 0.2 vertebral body height posterior to point T; puncture should avoid the aortic root area and the rear triangle area; the aortic root area could be negatively revealed by right atriography at the orifice of inferior vena cava, and the rear triangle area is demarcated by points C, C', and T' (C' and T' are 2 points horizontally posterior to, and at dCT away from points C and T, respectively). The initial application of CTP-2 in 2820 patients showed that it might be helpful in reducing the need of left atriography and the possibility of cardiac perforation.

Targeted Transseptal Access for MitraClip Percutaneous Mitral Valve Repair

Targeted transseptal puncture remains the most critical initial part of the overall MitraClip procedure. Care and attention must be implemented for patient safety in choosing the optimal puncture site. A consistent and step-by-step methodical approach is recommended. As experienced operators are targeting more complex and nontraditional pathologic conditions, use of adjunctive tools and maneuvers (outlined in this review) are paramount to achieving successful targeted transseptal access and ultimately procedural success.

Transseptal access in pediatric and congenital electrophysiology procedures: defining risk

PURPOSE

Transseptal puncture (TSP) is commonly used to access the left heart for catheter ablation procedures. The specific complication risk of this procedure has not been determined. This study assesses the risk of TSP using a single standard technique during electrophysiology study (EPS) in pediatrics and congenital heart disease (CHD).

METHODS

Retrospective cohort study of patients undergoing TSP during EPS at the University of Michigan Congenital Heart Center between 1999 and 2011.

RESULTS

There were 373 left heart ablation procedures during the study period. Excluded were six adults without CHD, five procedures using an alternative imaging modality, five procedures using retrograde aortic access, one transhepatic access, and one where TSP was performed during a prior procedure. Included were 321 pediatric (≤18 years old without CHD) TSP procedures (median age 13 years) and 34 TSP procedures in patients with CHD (median age 28 years). There was one complication directly attributable to TSP: needle perforation of the left atrium without development of effusion in the pediatric group. Post-procedure echocardiograms were performed in 351 (99 %) cases, showing only trivial effusions in seven (1.9 %).

CONCLUSIONS

This single center experience over 12 years shows the risk of TSP in pediatric and CHD patients to be low, with a 0.3 % (95 % confidence interval (CI) 0, 0.9 %) risk for complications directly related to TSP using only single plane fluoroscopy for visualization.

Aorto-right atrial fistula following transseptal catheterization and catheter ablation for atrial fibrillation

Aorto-cameral fistula, either congenital or acquired, is an abnormal connection between the ascending aortic root and one of the cardiac chambers. We report a case of a 61-year-old male with history of atrial fibrillation and 2 radiofrequency ablation procedures, referred to us for surgical Cox Maze procedure. Preoperative cardiac computerized tomography revealed a fistulous connection between the aortic root and the right atrium. Later, the patient underwent successful surgical closure of the fistula during the Cox Maze procedure. In this paper, we also discuss the clinical presentation, natural history, anatomy of the interatrial septum, and management of aorto-cameral fistula.

Pathophysiology of aortic stenosis and approach to treatment with percutaneous valve implantation

Aortic stenosis (AS) is the most commonly acquired valvular heart disease in the Western world (2-7% of the population aged > 65 years) and the mortality for untreated symptomatic severe AS is up to 50-60% at 2 years in high-risk patients. This review summarizes laboratory and recent clinical investigations concerning AS and current best treatment. Particular emphasis will be placed on pathophysiology and on the concept of after load mismatch and preload reserve in which left ventricular function is proportionately matched to level of left ventricular pressure, mainly because such studies carry important implications for both treatment with transcatheter aortic valve implantation (TAVI) and prognosis. Surgical aortic valve replacement is currently the gold-standard treatment for patients with severe symptomatic AS. Without surgery, the prognosis is extremely poor, with a 3-year survival rate < 30%. However, 33% of all patients aged ≥ 75 years with severe AS are declined for surgery. TAVI was recently introduced as a new therapeutic option for patients with AS, so the current indications, the technical differences between 2 different transcatheter aortic valves and the clinical available data will be also examined in detail. 

Particle formation and risk of embolization during transseptal catheterization: comparison of standard transseptal needles and a new radiofrequency transseptal needle

Objective

Anecdotally, the Brockenbrough transseptal needle generates plastic particles through a process of skiving (shaving off particles), when advanced through the dilator and sheath. This study was performed to assess particle creation by the Brockenbrough needle during transseptal catheterization. We explore strategies that may reduce this phenomenon, including use of the Brockenbrough stylet and a radiofrequency transseptal needle.

Method

In vitro simulations of transseptal catheterization were performed using Brockenbrough transseptal needles and a new radiofrequency transseptal needle. Particles that were created during advancement of transseptal needles through the sheath and dilator were collected and analyzed. Particles in the visible range of 50 μm to 4 mm were identified using a light microscope, whereas particles in the sub-visible, yet clinically relevant range of 10 to 50 μm, were counted using a light obscuration method.

Results

All simulated procedures using the Brockenbrough transseptal needles, with or without a stylet, generated visible particles. Simulated procedures with the radiofrequency transseptal needle generated no visible particles. A greater number of sub-visible particles were generated with the standard Brockenbrough transseptal needle (BKR-1) without stylet compared with the standard Brockenbrough needle (BRK-1) with stylet, the Brockenbrough extra sharp (BRK-1XS) needle with or without stylet, and the radiofrequency needle (NRG C1).

Conclusion

Clinically relevant particles, both visible and sub-visible, with the potential for causing embolic complications, are generated by the BRK-1 needle without stylet. Use of a stylet in the BRK-1 needle, or the BRK-1XS needle with or without stylet, appears to reduce the size and amount of particles created. The NRG C1 needle appears to eliminate visible particles and is comparable to the BRK-1 with stylet and the BRK-1XS with or without stylet in generation of sub-visible particles. Important steps can be taken to minimize the creation of particles during the advancement of the BRK-1 through the transseptal sheath and dilator.

New coaxial transseptal needle for creation of atrial septal defects in adult sheep

OBJECTIVES

To introduce a new transseptal (TS) needle assembled in our laboratory--the coaxial TS (CTS) needle--and describe our experience with it in creating experimental atrial septal defects (ASD) in adult sheep.

BACKGROUND

With commercially available TS needles, we were not able to consistently perform TS puncture at the fossa ovalis in adult sheep.

MATERIAL AND METHODS

Ten adult sheep with a mean weight of 63.5 kg were used. The CTS needle consists of four components: a 9F Teflon catheter, a 14-gauge blunt curved-tip metal cannula, a 4F tapered catheter, and a 20-gauge open needle. A transjugular 5F pigtail catheter was used to display the septal anatomy by angiocardiography and was left in place to mark the level of the fossa ovalis. The septum was then probed by a transfemoral 5F curved-tip end-hole catheter. The CTS needle was aligned with the tip of the transjugular catheter, and the TS puncture was performed under fluoroscopic guidance. After documenting a left atrial position, a balloon angioplasty catheter was used for creation of the ASD.

RESULTS

A small patent foramen ovale was discovered by septal probing in one sheep. All sheep underwent successful TS punctures without complications. The ASD size ranged from 13 to 15 mm. In eight sheep, the ASD was in fossa ovalis. In the first two sheep where the needle was not well aligned with the marking catheter, the ASD was in the septum secundum. No damage to the atrial or other heart structures was found at necropsy.

CONCLUSION

The CTS needle is a suitable needle for TS puncture and ASD creation in adult sheep. Proper alignment of the CTS needle with a catheter marking the fossa ovalis is essential for successful puncture.

Adventures in cardiovascular research

This article, derived from an invited Distinguished Scientist lecture presented at the American Heart Association Scientific Sessions in 2007, reviews 4 themes (adventures) in clinical cardiovascular research carried out over a period of 58 years. It begins with the author's introduction to cardiovascular hemodynamics during a medical school elective in 1951. The 4 adventures include valvular heart disease, hypertrophic cardiomyopathy, heart failure (HF), and myocardial ischemia. In each of these adventures, the author describes briefly what was known when he entered each field, followed by the author's contribution to the field (the adventure), and ends with comments about the current status of the field. Of particular interest are the changes in the technologies used in clinical cardiovascular research over the past half century, commencing with pressure tracings in left heart chambers with the use of needle puncture in the operating room to genetic technologies designed to understand differences between drugs that inhibit platelet activation. The article ends with some general comments on conducting research and the rewards that can come with this activity.