title: A Review Of The Relevant Embryology, Pathohistology, And Anatomy Of The Left Atrial Appendage For The Invasive Cardiac Electrophysiologist.
abstract: The three-dimensional morphology of the left atrial appendage provides the substrate for thrombus generation, and is a harbinger for embolic material due to its direct connection to the left-sided circulation. Appreciating the development of the appendage from mesodermal layer to its adult form provides the basis to improve exclusion from the atrial circulation, and thereby can lead to a significant reduction in stroke risk. This process also provides insight into the role of the left atrial appendage as an endocrine organ, its involvement in fluid homeostasis, and its connection to the autonomic nervous system. Knowledge of the surrounding structural arrangement is critical to identify landmarks from both an endocardial and epicardial perspective to improve targeted device placement. Furthermore, correlation of the left atrial appendage body, neck, and ostium to the surrounding anatomy can also improve both procedural efficacy and safety. In addition, a working knowledge of the regional anatomy adds a prudent degree of awareness for procedural complications, and allows for early identification and timely intervention as these situations arise. A detailed understanding of the left atrial appendage embryology, histology, and gross anatomy is imperative to identify the correct device and approach for each individual patient. In addition, this increased awareness can identify areas that are in need of further innovation, and thus provide the ability to adapt and refine existing technologies to overcome pitfalls currently facing catheter-based approaches.
authors.affiliation: Mayo Medical School, Mayo Clinic Rochester, Minnesota.
authors.forename: Christopher V
authors.initials: CV
authors.lastname: DeSimone
authors.affiliation: Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Bs Gaba
authors.initials: BG
authors.lastname: Prakriti
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Jason
authors.initials: J
authors.lastname: Tri
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Faisal
authors.initials: F
authors.lastname: Syed
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Amit Noheria
authors.initials: AN
authors.lastname: Sm
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota; Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Asirvatham
keywords: Cardiac Embryology; Embolism, Atrial Fibrillation; Left Atrial Appendage; Left Circumflex Artery; Mesenchymal; Ostium, Stroke; Phrenic Nerve; Pulmonary Vein; Vein Of Marshall, Endocardial Ridge