Transseptal Techniques for Emerging Structural Heart Interventions

Intracardiac echocardiography for guidance of transcatheter left atrial appendage occlusion: An expert consensus document

Transcatheter left atrial appendage occlusion (LAAO) is an increasingly used alternative to oral anticoagulation in selected patients with atrial fibrillation. Intraprocedural imaging is a crucial for a successful intervention, with transesophageal echocardiography (TEE) as the current gold standard. Since some important limitations may affect TEE use, intracardiac echocardiography (ICE) is increasingly used as an alternative to TEE for guiding LAAO. The lack of a standardized imaging protocol has slowed the adoption of ICE into clinical practice. On the basis of current research and expert consensus, this paper provides a protocol for ICE support of left atrial appendage occlusion.

Revascularization of Chronic Iliac Vein Occlusion Using Balloon-Assisted Transseptal Needle Puncture Technique

Objectives To evaluate the utility of a transseptal needle for balloon-assisted sharp recanalization of chronically occluded central venous structures.

Background Chronically occluded central veins are not an uncommon problem, which may arise due to a plethora of reasons. Traditionally, wire and catheter techniques are often used first in an attempt to reestablish flow. When these methods fail, more aggressive techniques are employed, such as sharp recanalization using the back end of wires, Teflon-coated wires, or Rosch–Uchida or Colapinto needles. However, utilization of transseptal needles, traditionally reserved for cardiac procedures, has rarely been described.

Methods Transseptal needle was utilized for balloon-assisted sharp recanalization after traditional wire and catheter techniques failed in revascularization of chronically occluded iliac veins.

Results Transseptal needle was utilized successfully in two cases in revascularization of chronically occluded central veins.

Conclusion Transseptal needle is a viable tool to add to the interventional radiologists’ armamentarium in reestablishing flow in chronically occluded central veins.

The role of CT in planning percutaneous structural heart interventions: Where to measure and why

As research continues to demonstrate successes in the use of percutaneous trans-vascular techniques in structural heart intervention, both the subspecialty trained and non-subspecialty trained cardiac imager find themselves performing and reporting larger amounts of information regarding cardiovascular findings. It is therefore imperative that the imager gains understanding and appreciation for how these various measurements are obtained, as well as their implication in a patient's care. Cardiac gated computed tomography (CT) has solidified its role and ability at providing high resolution images that can be used to obtain the key measurements used in structural heart intervention planning. This manuscript aims to provide an overview of what measurements are necessary to report when interpreting CT examinations purposed for structural heart intervention. This includes a review on indications and brief discussion on complications related to these procedures.

Initial clinical experience with VersaCross transseptal system for transcatheter mitral valve repair

OBJECTIVES

The aim of this study is to describe the initial experience with versacross transseptal (TS) system for transseptal puncture for the transcatheter mitral valve repair using the MitraClip device.

BACKGROUND

Transeptal puncture is a key step in transcatheter mitral valve repair (MVR) and the use of the VersaCross system comprised of a sheath, a dilator and a radiofrequency wire has not been previously described.

METHODS

Prospective single center study of consecutive patients undergoing transcatheter mitral valve repair with the MitraClip device were included. Targeted TS puncture was performed under transesophageal echocardiographic (TEE) guidance. Baseline demographics, procedural characteristics, and major adverse procedural events were collected.

RESULTS

Twenty-five consecutive patients underwent transseptal puncture using the VersaCross TS system. Transseptal puncture was successful in 100% of patients. The mean time for TS puncture was 3 3 ± 1.6 min with no major adverse procedural events. The mean time from insertion of the VersaCross system to insertion of the MitraClip guide catheter was 3.8 ± 3.0 minutes.

CONCLUSION

The VersaCross TS system was successful in all patients for MitraClip procedure with no adverse procedural events and may be associated with increased procedural efficiency.

Pre- and Postprocedural CT of Transcatheter Left Atrial Appendage Closure Devices

Transcatheter left atrial appendage (LAA) closure is an alternative to long-term anticoagulation therapy in selected patients with nonvalvular atrial fibrillation who have an increased risk for stroke. LAA closure devices can be implanted by means of either an endocardial or a combined endocardial and epicardial approach. Preprocedural imaging is key to identifying contraindications, accurately sizing the device, and minimizing complications. Transesophageal echocardiography (TEE) has been the reference standard imaging modality to assess the anatomy for LAA closure and to provide intraprocedural guidance. However, CT has emerged as a less-invasive alternative to TEE for pre- and postprocedural imaging. CT is comparable to TEE for exclusion of thrombus but is superior to TEE for the delineation of complex LAA anatomy, measurement for device sizing, and evaluation of pulmonary venous and extracardiac structures. CT provides accurate measurements of the LAA ostial diameter, landing zone diameter, and LAA length, which are vital for accurate sizing of the device. CT allows evaluation of the relationship with the pulmonary veins and other adjacent structures that can be injured during the procedure. CT also simulates procedural fluoroscopic angles and provides evaluation of the interatrial septum, which is punctured during LAA closure. CT also provides a more convenient method for the evaluation of postprocedural complications such as incomplete closure, peridevice leaking, device-related thrombus, and device dislodgement. Online supplemental material is available for this article. ^©RSNA, 2021.

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.

A new transseptal solution for enabling left atrial access of large delivery sheaths

BACKGROUND

Transseptal access for large sheaths may be encumbered by tissue resistance against the sheath-dilator stepped interface. The ExpanSure Large Access Transseptal Dilator (Baylis Medical) is designed as a single introducer and dilation device with a smooth sheath-dilator transition to support transseptal puncture. It may facilitate ease and efficiency of interatrial crossing.

METHODS

This study experimentally evaluated the crossing force of ExpanSure relative to a conventional 8.5 F Swartz SL1 transseptal sheath and dilator in a benchtop septum model. Its ability to reduce the subsequent crossing force of a 14 F WATCHMAN delivery sheath was also tested. The clinical use of ExpanSure, including procedure time, was then validated in a series of left atrial appendage closure (LAAC) procedures.

RESULTS

In a benchtop septum model (N = 12), less peak force (1.90 ± 0.08 N vs. 2.36 ± 0.09 N; p < .001) and overall work (17.3 ± 1.2 mJ vs. 28.0 ± 1.9 mJ; p < .001) were required to advance ExpanSure relative to a conventional SL1 transseptal sheath and dilator system. Peak force (2.34 ± 0.24 N vs. 2.65 ± 0.21 N; p < .003) and overall work (28.5 ± 3.9 mJ vs. 35.4 ± 2.1 mJ; p < .001) to advance a WATCHMAN sheath were also significantly lower after using ExpanSure than after using a conventional transseptal system. In 19 LAAC procedures, ExpanSure crossed the septum smoothly and integrated readily, which enabled efficient procedure completion (mean total procedure time 37.6 ± 13.5 min), with 100% success and no procedure-related complications.

CONCLUSION

Experimental force measurements, combined with early clinical experience using ExpanSure, suggest that the tapered design with smooth transition without dilator-sheath step-up and the larger diameter, both facilitated ease and efficiency of interatrial crossing.

A step-by-step guide to transseptal valve-in-valve transcatheter mitral valve replacement

With the recent success of transcatheter aortic valve replacement (TAVR), transcatheter options for the management of mitral valve pathology have also gained considerable attention. Valve-in-valve (ViV) transcatheter mitral valve replacement (TMVR) is one such technique that has emerged as a safe and effective therapeutic option for patients with degenerated mitral valve bioprostheses at high-risk for repeat surgical mitral valve replacement. Several access strategies, including trans-apical, transseptal, trans-jugular, and trans-atrial access have been described for ViV-TMVR. Initial experiences were performed primarily via a trans-apical approach through a left mini-thoracotomy because it offers direct access and coaxial device alignment. With the advancements in TMVR technology, such as the development of smaller delivery catheters with high flexure capabilities, the transseptal approach via the femoral vein has emerged as the preferred option. This technique offers the advantages of a totally percutaneous approach, avoids the need to enter the thoracic cavity or pericardial space, and provides superior outcomes compared to a trans-apical approach. In this review, we outline key aspects of patient selection, imaging, procedural techniques, and examine contemporary clinical outcomes of transseptal ViV-TMVR.

Multimodality imaging anatomy of interatrial septum and mitral annulus

The detailed anatomy of the interatrial septum (IAS) and mitral annulus (MA) as observed on cardiac magnetic resonance, computed tomography and two-dimensional/three-dimensional transthoracic and transesophageal echocardiography is reviewed. The IAS comprises of two components: the septum primum that is membrane-like forming the floor of the fossa ovalis (FO) and the septum secundum that is a muscular rim that surrounds the FO. The latter is an enfolding of atrial wall forming an interatrial groove. Named Waterston's groove, it is filled with adipose tissue on the epicardial side. Thus, the safest area for transseptal puncture (TSP) is within the limits of the FO floor, which provides direct interatrial access. While crossing an intact septum is a well-established procedure, TSP is a more complex and time-consuming procedure in the presence of patent foramen ovalis, aneurysmal FO or atrial septal defect closure devices. MA comprises two distinctive segments: an anterior-straight and a posterior-curved segment. The posterior MA is a thin, discontinuous fibrous 'string', interspersed with adipose tissue, where four components converge: the atrial and ventricular musculature, epicardial adipose tissue and the leaflet's hinge line. In parts of where this fibrous string is deficient or absent, the posterior leaflet is inserted directly on ventricular and atrial myocardium rendering the MA less robust and producing an 'asymmetric' dilation. The marked vulnerability of posterior MA to calcifications might be due to its insertion on the crest of ventricular myocardium being subject to friction injury due to the contraction and relaxation of LV.

Transcatheter mitral valve replacement

Transcatheter mitral valve (MV) repair, specifically the edge-to-edge leaflet repair, is a less invasive treatment of symptomatic mitral regurgitation (MR) in patients with high or prohibitive surgical risk. In cases with severe leaflet calcification, small mitral orifice area, and/or extremely wide regurgitation across the entire MV commissure, transcatheter MV repair may rather cause suboptimal or potentially hazardous outcomes. In these cases, MV replacement can be a more suitable option. Recently, percutaneous transcatheter MV replacement has emerged as an acceptable therapeutic option for the treatment of degenerated surgical bioprosthetic disease. Moreover, several transcatheter devices for native MV replacement are under evaluation with a hope to provide more complete and reproducible restoration of MV function. In this article, we will review current status, applications, clinical outcomes, and limitations that need to be overcome for transcatheter MV replacement for both degenerated surgical bioprosthetic disease and native MV disorders.

A novel and easy approach to difficult transseptal puncture during atrial fibrillation ablation

AIMS

Transseptal passage is sometimes difficult to obtain. This study evaluates the feasibility and safety of a novel and easy transseptal puncture (TSP) technique named 2D2G (using two dilators and two guidewires) in patients with difficult TSP.

METHODS AND RESULTS

Forty-four paroxysmal atrial fibrillation patients with difficult TSP were enrolled in this study. They were allocated to the 2D2G group or the conventional group in a 1:1 fashion. The primary endpoint in both groups was successful TSP without changing the puncture site or using auxiliary tools. The secondary endpoints were the safety, total transseptal puncture time, and ablation time. There were no differences in baseline demographic or clinical characteristics between the two groups. Successful LA access in the 2D2G group was 100% (vs. 64%, P < 0.05). The total TSP time (10 ± 3 min vs. 5 ± 1 min, P < 0.05) and ablation time (42 ± 19 min vs. 58 ± 22 min, P < 0.05) in the conventional group were significantly longer than those in the 2D2G group. No major complications occurred in either group, and all the patients underwent successful circumferential pulmonary vein isolation (CPVI).

CONCLUSION

In AF patients with difficult TSP, the 2D2G technique is safe, feasible, and time-saving.

Imaging Guidance for Transcatheter Mitral Valve Intervention on Prosthetic Valves, Rings, and Annular Calcification

Catheter-based interventions to improve mitral valve function are dependent on anatomic and functional information provided by noninvasive imaging to plan, perform, and evaluate each intervention. In this review we highlight the importance of imaging guidance for catheter-based interventions on prosthetic mitral valves, surgical rings, and native valve annular calcification. Both repair and replacement procedures are discussed. We review the general features common to this collection of procedures and discuss specific imaging issues and concerns for each procedure. Figures and intraprocedural videos emphasize central messages using case examples.

3D printing tissue-mimicking materials for realistic transseptal puncture models

Applications of additive manufacturing (commonly referred to as 3D printing) in direct fabrication of models for pre-surgical planning, functional testing, and medical training are on the rise. However, one current limitation to the accuracy of models for cardiovascular procedural training is a lack of printable materials that accurately mimic human tissue. Most of the available elastomeric materials lack mechanical properties representative of human tissues. To address the gap, the authors explore the multi-material capability of material jetting additive manufacturing to combine non-curing and photo-curing inks to achieve material properties that more closely replicate human tissues. The authors explore the impact of relative material concentration on tissue-relevant properties from puncture and tensile testing under submerged conditions. Further, the authors demonstrate the ability to mimic the mechanical properties of the fossa ovalis, which proves beneficial for accurately simulating transseptal punctures. A fossa ovalis mimic was printed and assembled within a full patient-specific heart model for validation, where it exhibited accuracy in both mechanical properties and geometry. The explored material combination provides the opportunity to fabricate future medical models that are more realistic and better suited for pre-surgical planning and medical student training. This will ultimately guide safer, more efficient practices.

Role of 3-dimensional transesophageal echocardiography in guiding transcatheter mitral valve replacement

BACKGROUND

Transcatheter mitral valve replacement technologies have been developed to treat a wide range of mitral valve pathologies including primary and secondary mitral regurgitation, mitral stenosis, in addition to degenerative bioprosthetic valves and failed annuloplasty rings.

OBJECTIVE

Transesophageal echocardiography, particularly with use of 3-dimensional imaging is key in successfully guiding these interventions. In this review, we highlight the key role of 3D transesophageal echocardiography in guiding TMVR, including valve-in-native valve, valve-in-prosthetic valve, valve-in-prosthetic ring, and valve-in-mitral annular calcification interventions.

Acute Decompensated Heart Failure in Patients with Heart Failure with Reduced Ejection Fraction

Acute decompensated heart failure (ADHF) requires immediate treatments because it impairs perfusion to systemic organs and their function. Half of all patients with ADHF are diagnosed with heart failure with reduced left ventricular ejection fraction (HFrEF). The initial goal of management for ADHF is to stabilize hemodynamic status. Pulmonary edema is treated with vasodilators or diuretics. Inhibitors of the renin-angiotensin-aldosterone system and β-blockers should be started and/or increased to meet the maximum dose, ideally the target dose, that the patient can tolerate as a treatment of HFrEF. Patients with severe circulatory failure need inotropic drugs or mechanical circulatory support.

Ridges and Pouches: A Case Series of Anomalous Atrial Septal Fusion

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Left atrial ridge may affect planning of trans-septal approach for interventions.

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Left atrial septal pouch may become a nidus for thrombus and source of embolus.

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Complete interrogation of the atrial septum can identify these anatomic variants.

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.

Predictors of adverse outcomes after transcatheter mitral valve replacement

Introduction: Transcatheter mitral valve replacement (TMVR) is still a recent technology with numerous unknowns but also great promises. The risk of complications reported in observational studies have limited its adoption by interventional cardiology and surgical communities. Areas covered: Some of the major setbacks of TMVR are complications related to the devices and those related to the pathway. Device-related complications include left ventricle outflow tract (LVOT) obstruction, transcatheter heart valve (THV) dislocation or embolization, thrombosis, and stroke. The transapical approach currently remains the main pathway for TMVR but is associated with high risk of major bleeding and residual apical myocardial scarring. Complication prediction and prevention seem possible. Device-related complication prediction is based on pre-operative imaging including multi-slice computed tomography with 3-dimensional reconstructions and echocardiography which allow LVOT obstruction prediction and appropriate sizing aiming at avoiding dislocation. Industry should aim at the development of transfemoral delivery systems. Nevertheless, several recent feasibility observational studies suggested acceptable safety and efficacy of transcatheter mitral valve replacement. Expert opinion: TMVR complications and transapical delivery are some of the main setbacks which need to be addressed for TMVR to be adopted for broad clinical use.

An augmented reality system for image guidance of transcatheter procedures for structural heart disease

The primary mode of visualization during transcatheter procedures for structrural heart disease is fluoroscopy, which suffers from low contrast and lacks any depth perception, thus limiting the ability of an interventionalist to position a catheter accurately. This paper describes a new image guidance system by utilizing augmented reality to provide a 3D visual environment and quantitative feedback of the catheter’s position within the heart of the patient. The real-time 3D position of the catheter is acquired via two fluoroscopic images taken at different angles, and a patient-specific 3D heart rendering is produced pre-operatively from a CT scan. The spine acts as a fiduciary land marker, allowing the position and orientation of the catheter within the heart to be fully registered. The automated registration method is based on Fourier transformation, and has a high success rate (100%), low registration error (0.42 mm), and clinically acceptable computational cost (1.22 second). The 3D renderings are displayed and updated on the augmented reality device (i.e., Microsoft HoloLens), which can provide pre-set views of various angles of the heart using voice-command. This new image-guidance system with augmented reality provides a better visualization to interventionalists and potentially assists them in understanding of complicated cases. Furthermore, this system coupled with the developed 3D printed models can serve as a training tool for the next generation of cardiac interventionalists.

Percutaneous Techniques, Limitations and Challenges for the Failed Surgical Mitral Intervention

The advent of percutaneous therapies has significantly altered therapeutic options for patients with valvular heart disease. Building on the success of transcatheter aortic valve replacement, both expanded indications and purpose-built devices are now being used to address percutaneous approaches for mitral valve pathology. While surgical mitral valve repair remains the gold standard for addressing significant mitral valve pathology, there has been a progressive increase in the utilization of bioprosthetic valves despite their limited lifespan. The risks of reoperation to address mitral valve repair failure or bioprosthetic valve dysfunction is not insignificant. In light of the aging population and the potential for significant associated comorbidities, less invasive alternative techniques hold particular appeal. Utilization of commercially available transcatheter aortic valve replacement valves for failed surgical valves has been shown to have better short-term mortality than would be predicted for open reoperation. As a result, the US Food and Drug Administration approved the utilization of transcatheter mitral valve-in-valve replacement for the failed bioprosthetic valve in high surgical risk patients. Despite the favorable outcomes, transcatheter mitral valve-in-valve is not without procedural challenges and potential complications including malpositioning, embolization, paravalvular leak, and outflow tract obstruction. Awareness of these challenges, mitigation strategies, and therapeutic options is imperative to optimizing outcomes in this high-risk patient population.

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.

Transcatheter Mitral Valve Repair Using the Edge-to-Edge Clip

Percutaneous intervention for mitral valve (MV) disease has been established as an alternative to open surgical MV repair in patients with prohibitive surgical risk. Multiple percutaneous approaches have been described and are in various stages of development. Edge-to-edge leaflet plication with the MitraClip (Abbott, Menlo Park, CA) is currently the only Food and Drug Administration-approved device specifically for primary or degenerative lesions. Use of the edge-to-edge clip for secondary mitral regurgitation is currently under investigation and may result in expanded indications. Echocardiography has significantly increased our understanding of the anatomy of the MV and provided us with the ability to classify and quantify the associated mitral regurgitation. For percutaneous interventions of the MV, transesophageal echocardiography imaging is used for patient screening, intraprocedural guidance, and confirmation of the result. Optimal outcomes require the echocardiographer and the proceduralist to have a thorough understanding of intra-atrial septal and MV anatomy, as well as an appreciation for the key points and potential pitfalls of each of the procedural steps. With increasing experience, more complex valvular pathology can be successfully percutaneously treated. In addition to two-dimensional echocardiography, advances in three-dimensional echocardiography and fusion imaging will continue to support the refinement of current technologies, the expansion of clinical applications, and the development of novel devices.

Mechanical circulatory support in patients with severe aortic stenosis and left ventricular dysfunction undergoing percutaneous coronary intervention

Management of obstructive coronary artery disease in patients with aortic stenosis and severe left ventricular dysfunction is challenging. Mechanical circulatory support at the time of percutaneous coronary interventions may be necessary in these extreme-risk patients. We present a case in which the TandemHeart was used to support a patient with severe aortic stenosis, severe protected left main and circumflex disease, and severe cardiomyopathy and review the literature on this subject.