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Standardized Review of Atrial Anatomy for Cardiac Electrophysiologists See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/235416273 Standardized Review of Atrial Anatomy for Cardiac Electrophysiologists Article in Journal of Cardiovascular Translational Research · February 2013 DOI: 10.1007/s12265-013-9447-2 · Source: PubMed CITATIONS READS 7 57 5 authors, including: Damián Sánchez-Quintana Gonzalo Pizarro Universidad de Extremadura Spanish National Centre for Cardiovascular R… 167 PUBLICATIONS 3,792 CITATIONS 43 PUBLICATIONS 416 CITATIONS SEE PROFILE SEE PROFILE Jose Ramon Lopez Minguez José Angel Cabrera Hospital Universitario Infanta Cristina de Bad… European University of Madrid 107 PUBLICATIONS 1,174 CITATIONS 100 PUBLICATIONS 2,865 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: REPARA View project Interventional cardiology View project All content following this page was uploaded by Damián Sánchez-Quintana on 11 October 2016. The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately. Standardized Review of Atrial Anatomy for Cardiac Electrophysiologists Damián Sánchez-Quintana, Gonzalo Pizarro, José Ramón López-Mínguez, Siew Yen Ho & José Angel Cabrera Journal of Cardiovascular Translational Research ISSN 1937-5387 Volume 6 Number 2 J. of Cardiovasc. Trans. Res. (2013) 6:124-144 DOI 10.1007/s12265-013-9447-2 1 23 Your article is protected by copyright and all rights are held exclusively by Springer Science +Business Media New York. This e-offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self-archive your work, please use the accepted author’s version for posting to your own website or your institution’s repository. You may further deposit the accepted author’s version on a funder’s repository at a funder’s request, provided it is not made publicly available until 12 months after publication. 1 23 Author's personal copy J. of Cardiovasc. Trans. Res. (2013) 6:124–144 DOI 10.1007/s12265-013-9447-2 Standardized Review of Atrial Anatomy for Cardiac Electrophysiologists Damián Sánchez-Quintana & Gonzalo Pizarro & José Ramón López-Mínguez & Siew Yen Ho & José Angel Cabrera Received: 23 October 2012 /Accepted: 22 January 2013 /Published online: 7 February 2013 # Springer Science+Business Media New York 2013 Abstract Catheter ablation of cardiac arrhythmias has rap- relationship to other structures. This article is part of a JCTR idly evolved from a highly experimental procedure to a special issue on Cardiac Anatomy. standard form of therapy for various tachyarrhythmias. The advances in this field have included, first, the develop- Keywords Morphological substrate . Atrial fibrillation . ment of techniques of catheter ablation that often requires Atrial flutter . Pulmonary vein . Myoarchitecture the precise destruction of minute amounts of arrhythmo- genic tissues and, second, techniques of resynchronization therapy that require pacing different parts of the ventricles. Introduction A detailed prepocedural knowledge of cardiac anatomy can improve the safety of the procedure and its rate success. It The adoption of percutaneous interventional procedures for helps the electrophysiologist to choose the appropiate region the treatment of both structural heart defects and tachyarrhyth- for ablation, shortening the procedural time. The atrial anat- mias in humans has increased the interest in cardiac anatomy. omy structures are usually localized before ablation by Although new diagnostic techniques are now permitting the different imaging techniques such as fluoroscopy, electro- shape of the atrial cavities to be reconstructed with exquisite anatomic mapping, intracardiac echocardiography or multi- accuracy, and are revealing remarkably variable arrangements detector computed tomography. In this review, we describe of structures such as the pulmonary veins, it is helpful if the the normal anatomy of the atria, highlighting the landmarks interventional cardiologist can comprehend the morphologic of interest to intervencional cardiologist, stressing their and architectural features of the atrial chambers as seen in the autopsied heart. In addition, a new investigational wave has D. Sánchez-Quintana (*) emerged leading to revisitation of anatomic topics within the Departamento de Anatomía y Biología Celular, heart for which the information was incomplete or simply Facultad de Medicina, Universidad de Extremadura, wrong. As a result, recent studies have unraveled anatomic Avenida de Elvas s/n, 06071 Badajoz, Spain features, architectural aspects, and histological details of cer- e-mail: [email protected] tain components of the heart that are of fundamental impor- tance to those seeking to understand the substrates of D. Sánchez-Quintana tachycardias and their ablation [1–3]. It is also necessary to e-mail: [email protected] understand the arrangement of the cardiomyocytes aggregated : G. Pizarro J. A. Cabrera together to form the atrial walls, since this information can Hospital Universitario Quirón-Madrid, provide us with a better understanding of the preferential European University of Madrid, Madrid, Spain routes of conduction from one part of the atrium to the other J. R. López-Mínguez [4]. At the same time, it is important to know how the Servicio de Cardiología, Sección de Hemodinámica, myocardial walls of the two atrial chambers are joined togeth- Hospital Infanta Cristina, Badajoz, Spain er, and to recognize the location of the sinus node, the initiator of atrial activation. Our current purpose, therefore, is to review S. Y. Ho Cardiac Morphology Unit, Royal Brompton Hospital, the gross morphological and structural details of the right and Imperial College, London, UK left atria, concentrating of features such as the terminal crest, Author's personal copy J. of Cardiovasc. Trans. Res. (2013) 6:124–144 125 the cavotricuspid isthmus, Koch’s triangle and its content, the sagittal plane. Instead, it is orientated obliquely from ante- Eustachian ridge and valve, the pulmonary venous orifices riorly to posteriorly rightward at an angle of around 65° to and their neighboring left atrial landmarks, and the architec- the sagittal plane [5]. Owing to the obliquity of this septal ture of the venoatrial junctions. We also discuss the anatom- plane and the difference between the levels of the mitral and ical features of important structures in the neighborhood of the tricuspid valvar orifices, the left atrial chamber is situated atria and the pulmonary veins, such as the esophagus and more posteriorly and superiorly than its right-sided counter- phrenic nerves. part. The pulmonary veins enter the posterior part of the left atrium, with the left veins located more superiorly than the right veins. The orifices of the right pulmonary veins are Location of the Atria directly adjacent to the plane of the atrial septum. The transverse pericardial sinus lies anterior to the left atrium, Both the right and left atrial chambers lie to the right of their and in front of this sinus is the root of the aorta. The tracheal respective ventricular chambers. Viewed from the front, the bifurcation, the esophagus, and descending thoracic aorta cavity of the right atrium is rightward and anterior, while are immediately behind the pericardium, being directly re- that of the left atrium is mainly positioned posteriorly lated to the posterior wall of the left atrium (Fig. 1). Further (Fig. 1). The plane of the atrial septum does not run in the behind is the vertebral column. Fig. 1 a This picture of an endocast from a normal heart photographed tilted right superior and left perspectives, respectively, to show the in attitudinally appropriate position, with the so-called “right heart” in courses of the esophagus (Eso) and descending aorta relative to the blue and the “left heart” in red. As can be seen, the right atrium lies left atrium. CS coronary sinus, ICV inferior caval vein, LAA left atrial anterior to its alleged left-sided counterpart. Note the arrangement of appendage, LIPV left inferior pulmonary vein, LPA left pulmonary the terminal crest (white broken line). b External appearance of the artery, LSPV left superior pulmonary vein, OF oval fossa, RAA right right and left atriums viewed from superior view. Note the location of atrial appendage, RIPV right inferior pulmonary vein, RPA right the transverse sinus (yellow dotted line) and its relationship to the aorta, pulmonary artery, RS right superior pulmonary vein, SCV superior pulmonary trunk (PT) and atrial walls. c, d Specimens viewed from the caval vein Author's personal copy 126 J. of Cardiovasc. Trans. Res. (2013) 6:124–144 Spatial Location of the Atrial Chambers (Fig. 2), an inconstant and rudimentary valve seen as a During an Electrophysiological Study crescentic fold. The left atrium has an obvious smooth-walled body Two or more fluoroscopic views are usually needed to (Figs. 1 and 2), interposed between the vestibular and pul- define the anatomic position in the heart and to estimate monary venous components, with the pulmonary veins en- more accurately the location of the exploring electrode. The tering at the four corners of the venous part, enclosing a frontal view is used to introduce and position catheters in the prominent atrial dome (Fig. 1). Typically, two veins, posi- apex and outflow tract of the
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