Transcatheter pulmonic valve implantation: Techniques, current roles, and future implications

Emerging Transcatheter Therapies for Valvular Heart Disease: Focus on Mitral and Tricuspid Valve Procedures

The emergence of percutaneous treatment options provides novel therapeutic alternatives for older and feeble patients who are at high risk for any surgical procedure. The purpose of our review was to offer an up-to-date analysis of the rapidly expanding field of percutaneous technologies for mitral, tricuspid, and pulmonary procedures. Edge-to-edge repair is an established treatment for secondary mitral regurgitation (MR), while transcatheter mitral valve replacement is a potential and expanding option for managing both secondary and primary MR. However, additional advancements are necessary to enhance the safety and feasibility of this procedure. Transcatheter tricuspid intervention is an emerging option that was conceived after the success of transcatheter procedures in aortic and mitral valves, and it is currently still in the early stages of advancement. This can be attributed, at least in part, to the previously overlooked effect of tricuspid regurgitation on patient outcomes. The development of edge-to-edge repair represents the forefront of innovations in transcatheter procedures. There is a scarcity of data about tricuspid annuloplasty and replacement, and further study is necessary. Transcatheter mitral, tricuspid, and pulmonary procedures show prospects for the future, while their role in clinical practice has not been definitively established.

Transcatheter-Based Interventions for Tetralogy of Fallot Across All Age Groups

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Palliative procedures, either surgical or transcatheter, aim to improve oxygen saturation, affording definitive procedures at a later stage. Transcatheter interventions have been used before and after surgical palliative or definitive repair in children and adults. This review aims to provide an overview of the different catheter-based interventions for TOF across all age groups, with an emphasis on palliative interventions, such as patent arterial duct stenting, right ventricular outflow tract stenting, or balloon pulmonary valvuloplasty in infants and children and transcatheter pulmonary valve replacement in adults with repaired TOF, including the available options for a large, dilated native right ventricular outflow tract.

Standardized Bench Test Evaluation of Biomechanical Characteristics of Stents Used in Right Ventricular Outflow Tract Revalvulation

PURPOSE

Pre-stenting of the right ventricular outflow tract (RVOT) is commonly performed before percutaneous pulmonary valve implantation (PPVI), to relieve obstruction, prevent valved stent fractures, and provide a landing zone. This study aimed to evaluate the biomechanical characteristics of the stents currently used to perform pre-stenting of the RVOT.

METHODS

We assessed five commercially available stents: Cheatham-Platinum Stent ("CP Stent"), AndraStent XL, AndraStent XXL, Optimus XL, and Optimus XXL. Following stent deployment at nominal pressure, radial and longitudinal elastic recoils and radial resistance were measured. The bending stiffness of the stents crimped onto the balloons was also evaluated.

RESULTS

Three samples were tested for each stent. Our study showed no significant difference between the stent platforms in terms of radial elastic recoil, which was relatively low (< 10%). The longitudinal elastic recoil was also low for all the devices (< 5%). Significant differences were observed in radial resistance (P < 0.001). CP Stent and AndraStent XL exhibited the highest radial resistances. The bending stiffnesses of the stents crimped on their balloons were significantly different (P < 0.00001). Optimus XL and XXL were more flexible than the other stents.

CONCLUSION

This study highlights the significant differences between the stents currently used in RVOT pre-stenting. Stents with good radial resistance are preferred, especially for calcified vessels, and flexibility is crucial for tortuous vessels. We proposed an algorithm for selecting the most suitable stent according to the need for radial force and flexibility, which will help inform clinicians considering RVOT revalvulation.

The Role of Palliative Care in Cardiovascular Disease

The American Heart Association has recommended that palliative care be integrated into the care of all patients with advanced cardiac illnesses. Notwithstanding, the number of patients receiving specialist palliative intervention worldwide remains extremely small. This review examines the nature of palliative care and what is known about its delivery to patients with cardiac illness. Most of the published literature on the subject concern advanced heart failure; however, some data also exist regarding patients with heart transplantation, pulmonary hypertension, valvular disease, congenital heart disease, indwelling devices, mechanical circulatory support, and advanced coronary disease. In addition, outcome data, certification requirements, workforce challenges, barriers to implementation, and a potential caveat about palliative care will also be examined. Further work is required regarding appropriate means of implementation, quality control, and timing of intervention.

Multimodality Imaging of the Neglected Valve: Role of Echocardiography, Cardiac Magnetic Resonance and Cardiac Computed Tomography in Pulmonary Stenosis and Regurgitation

The pulmonary valve (PV) is the least imaged among the heart valves. However, pulmonary regurgitation (PR) and pulmonary stenosis (PS) can occur in a variety of patients ranging from fetuses, newborns (e.g., tetralogy of Fallot) to adults (e.g., endocarditis, carcinoid syndrome, complications of operated tetralogy of Fallot). Due to their complexity, PR and PS are studied using multimodality imaging to assess their mechanism, severity, and hemodynamic consequences. Multimodality imaging is crucial to plan the correct management and to follow up patients with pulmonary valvulopathy. Echocardiography remains the first line methodology to assess patients with PR and PS, but the information obtained with this technique are often integrated with cardiac magnetic resonance (CMR) and computed tomography (CT). This state-of-the-art review aims to provide an updated overview of the usefulness, strengths, and limits of multimodality imaging in patients with PR and PS.

Role of computed tomography in transcatheter replacement of 'other valves': a comprehensive review of preprocedural imaging

Transcatheter procedures for heart valve repair or replacement represent a valid alternative for treating patients who are inoperable or at a high risk for open-heart surgery. The transcatheter approach has become predominant over surgical intervention for aortic valve disease, but it is also increasingly utilized for diseases of the 'other valves', that is the mitral and, to a lesser extent, tricuspid and pulmonary valve. Preprocedural imaging is essential for planning the transcatheter intervention and computed tomography has become the main imaging modality by providing information that can guide the type of treatment and choice of device as well as predict outcome and prevent complications. In particular, preprocedural computed tomography is useful for providing anatomic details and simulating the effects of device implantation using 3D models. Transcatheter mitral valve replacement is indicated for the treatment of mitral regurgitation, either primary or secondary, and computed tomography is crucial for the success of the procedure. It allows evaluating the mitral valve apparatus, the surrounding structures and the left heart chambers, identifying the best access route and the landing zone and myocardial shelf, and predicting obstruction of the left ventricular outflow tract, which is the most frequent postprocedural complication. Tricuspid valve regurgitation with or without stenosis and pulmonary valve stenosis and regurgitation can also be treated using a transcatheter approach. Computer tomography provides information on the tricuspid and pulmonary valve apparatus, the structures that are spatially related to it and may be affected by the procedure, the right heart chambers and the right ventricular outflow tract.