Transcatheter Mitral Valve Therapies

Ron Waksman, Toby Rogers, Dr. Ron Waksman, Dr. Toby Rogers, Dr. Ted Feldman, Ron Waksman, Toby Rogers, Ted Feldman

• Publisher: Wiley-Blackwell
• Year: 2021
• Print ISBN: 9781119490685
• eBook ISBN: 9781119490654
• Edition: 1
• Topic: Medicine
• Subtopic: Cardiology

TRANSCATHETER MITRAL VALVE THERAPIES

An essential survey of the advancing field of transcatheter mitral valve repair and replacement

Minimally invasive transcatheter therapies have revolutionized the treatment of structural heart disease. Greatly improving outcomes for higher-risk patients, transcatheter aortic valve replacement is now established as a safe and effective alternative to invasive surgery. The mitral valve, however, poses further challenges. Contending with one of the heat's most anatomically and pathologically complex components, practitioners and engineers have yet to perfect a stream-lined, widely deliverable therapy—though they are getting closer and closer to this goal.

Transcatheter Mitral Valve Therapies provides a far-reaching survey of the field of mitral interventions in its current state. Highlighting the stumbling blocks preventing transcatheter mitral valve replacement's widespread adoption, the book's international group of contributors discuss the improvements to be made in repair and replacement procedures, as well as the adjunctive use of imaging and pharmacologic therapies. This ground-breaking text:

• Provides detailed explanations of transcatheter repair, transcatheter replacement, and adjunctive procedures
• Features chapters on the use of imaging to aid in patient selection, procedure planning, and intra-operative guidance
• Discusses the importance of minimally invasive approaches for mitral valve repair
• Examines anticoagulation following transcatheter mitral valve interventions
• Outlines the possible future of transcatheter mitral valve therapy

Transcatheter Mitral Valve Therapies is an important, up-to-date resource for interventional cardiologists, as well as all clinical researchers and practitioners seeking information on this vital and developing treatment.

1
The Pathology of Mitral Valve Disease

Maria E. Romero, Sho Torii, and Renu Virmani

CVPath Institute, Inc., Gaithersburg, MD, USA

1.1 Introduction

Mitral valve (MV) insufficiency is a major causation of heart failure and cardiac death, with complications of arrhythmia, endocarditis, and sudden cardiac death [1, 2]. The most common clinical finding in degenerative valve disease is elongation and or rupture of the chordal apparatus resulting in leaflet prolapse, and varying degrees of mitral valve regurgitation due to abnormal leaflet coaptation during ventricular contraction [3]. Up to one third of all patients requiring mitral valve repair/replacement are at high operative risk for surgery [4]. Surgical mitral valve treatment is still the gold standard for treating severe mitral valve insufficiency; however, controversy exists as to whether early surgical intervention in asymptomatic patients before the onset of ventricular changes improves the outcome of patients with severe degenerative mitral valve disease [2, 5–7]. For patients with high surgical risk, transcatheter mitral valve device has become a therapeutic option [8]. This chapter highlights the mitral valve anatomy, pathophysiology of normal mitral valve, mitral stenosis (MS), and mitral regurgitation (MR).

1.2 General Anatomy of the Mitral Valve

The mitral valve is a two‐leaflet valve with a saddle‐shaped annulus and its valvular plane facing anteriorly, inferiorly, and to the left [9–12]. The mitral valve apparatus, both functionally and morphologically, consists of a constellation of individual structures, which consist of the annulus, anterior and posterior leaflets, chordae tendineae, papillary muscles (PMs), and also include the left ventricular wall and the left atrium which are essential for the valve to function normally. The valve is obliquely located in the heart and has a close relation to the aortic valve [13].

1.2.1 Mitral Annulus

The mitral annulus, the hinge line of the valvular leaflets, is “D”‐shaped, unlike the aortic annulus which is circular (Figure 1.1a). The geometric “saddle shape” of the mitral annulus has the highest point of the saddle located in the middle of the anterior leaflet. During ventricular systolic phase, the mitral annulus folds at the intercommissural axis. This folding helps coaptation of the leaflet and prevents leaflet distortion along the lines of annular attachment, and reduces the pressure exerted on the mitral valve leaflets [15]. The normal annular circumference is <10 cm and the normal mitral valve orifice area is 4–6 cm². The anterior annulus spans the left and right fibrous trigones and is anatomically coupled to the aortic annulus (Figure 1.2). The right fibrous trigone is thicker with more fibrous tissue than left fibrous trigone; however, there is significant variability from heart to heart [16]. Both the trigones are extension of the fibrous tissue at the two ends of the aortomitral continuity. The central fibrous body is formed by the membranous septum together with the right trigone. The atrioventricular conduction bundle passes through the right fibrous trigone. There is a close relationship of the coronary sinus to the posterior mitral annulus and the left circumflex artery lies adjacent to the left trigone and passes inferior to continuation of the coronary sinus (Figure 1.3). The annulus opposite the area of valvular fibrous continuity tends to be weaker in terms of lacking a well‐formed fibrous cord. This is the area affected in annular dilatation and also most often involved in calcification of the annulus [13].

Figure 1.1 Normal mitral valve. (a) Gross atrial view of the mitral valve showing anterior and posterior leaflets. (b) The anterior leaflet is larger, and the chordae arise from the ventricular surface at 45° angle. The anterior leaflet is separated from the posterior leaflet by the commissures (*) with fan‐shaped branching commissural chordae. The posterior leaflet has three, often poorly defined, scallops, each with chordal attachments. (c) A histological section of a mitral valve leaflet (Movat pentachrome stain) demonstrates the atrial surface which is rich in elastic fibers and collagen, glycosaminoglycans‐rich spongiosa in the mid portion (green), and dense collagenous tissue (yellow) which is observed on the ventricular surface of the leaflet. Abbreviations: AML, anterior mitral leaflet; PML, posterior mitral leaflet.

Source: Reproduced with permission from Torii et al. [14].

Figure 1.2 Long axis view of the heart demonstrating the fibrous continuity of the anterior leaflet with the non‐coronary sinus. The atrioventricular junction is shown in the longitudinal view; the interatrial septal wall (arrows) is separated by the transverse sinus from the aorta. Note the fibrous continuity of the anterior leaflet with the non‐coronary sinus. Abbreviations: AML, anterior mitral leaflet; NCS, non‐coronary sinus; PML, posterior mitral leaflet; PM, papillary muscle; RCS, right coronary sinus; RV, right ventricle; VS; ventricul...

Table of contents

• Cover
• Table of Contents
• Title Page
• Copyright Page
• List of Contributors
• Introduction—The Mitral Book
• 1 The Pathology of Mitral Valve Disease
• 2 The Importance of Minimally Invasive Approaches for Mitral Valve Repair
• 3 When to Intervene—Should Surgical Guidelines Apply to Transcatheter Techniques in Treating Mitral Regurgitation?
• 4 Transcatheter Mitral Valve Therapies
• 5 CMR Assessment of Mitral Regurgitation
• 6 CT Planning for TMVR and Predicting LVOT Obstruction
• 7 General Principles and State‐of‐the‐Art Echocardiographic Evaluation of the Mitral Valve
• 8 Intraprocedural Echocardiography for MitraClip
• 9 Intraprocedural Echocardiography for Transcatheter Mitral Valve Replacement
• 10 Transcatheter Repair
• 11 MitraClip™ for Secondary Mitral Regurgitation
• 12 The Edwards PASCAL Transcatheter Valve Repair System
• 13 The Development of a Novel Percutaneous Treatment for Secondary Mitral Regurgitation—The Carillon® Mitral Contour System®
• 14 A Fully Percutaneous Mitral Ring
• 15 Transcatheter Mitral Cerclage Annuloplasty
• 16 The Transapical Off‐Pump Mitral Valve Repair with the NeoChord Implantation (TOP‐MINI)
• 17 AltaValve™—A Transcatheter Mitral Valve Regurgitation Treatment Technology
• 18 The ARTO Transcatheter Mitral Valve Repair System
• 19 Transcatheter Mitral Annuloplasty
• 20 Transapical and Transseptal Access for Transcatheter Mitral Valve Replacement
• 21 Mitral Valve‐in‐Valve and Valve‐in‐Ring Therapies
• 22 Edwards SAPIEN in Native Mitral Annular Calcification (MAC)
• 23 Transcatheter Mitral Valve Replacement
• 24 TIARA Transcatheter Mitral Replacement System
• 25 Caisson Transcatheter Mitral Valve Replacement System
• 26 Transcatheter Mitral Valve Replacement with the CardiAQ‐Edwards and EVOQUE Prostheses
• 27 Intrepid
• 28 Laceration of the Anterior Mitral Leaflet to Prevent Outflow Obstruction (LAMPOON)
• 29 Use of Alcohol Septal Reduction Therapy to Facilitate Transcatheter Mitral Valve Replacement
• 30 Direct Transatrial Approach with Resection of the Anterior Mitral Leaflet to Prevent Outflow Tract Obstruction
• 31 Transcatheter Closure of Mitral Paravalvular Leak
• 32 Management of Iatrogenic Interatrial Septal Defect—To Close or not to Close?
• 33 Antithrombotic Therapy in Transcatheter Mitral Valve Intervention
• Index
• End User License Agreement