Correlative Anatomy for the Electrophysiologist, Part II: Cardiac Ganglia, Phrenic Nerve, Coronary Venous System

Abstract

Cardiac Ganglia, Phrenic Nerve, Coronary Venous System. There is an increasing need for invasive electrophysiologists to appreciate the exact anatomy of the epicardial space and the coronary veins. The location of the epicardial fat, the complementary relationship with the main cardiac veins, and the location of sensitive structures (arteries, phrenic nerve, esophagus) have become required knowledge for electrophysiologists, and accessing the epicardial space with this thorough knowledge of the pericardial sinuses and recesses is essential to allow radiographic correlation during catheter manipulation. In this review, we briefly describe the anatomy of the pericardial space and then discuss the specific correlation for the invasive electrophysiologist, highlighting epicardial access, catheter navigation, and avoidance of collateral injury, with specific attention to the important recesses of the pericardial space, their regional anatomy, and radiographic correlation when navigating catheters to these locations. We also discuss the anatomy of the main cardiac veins in the context of catheter mapping and ablation of the epicardial substrate through the venous system and without subxiphoid pericardial access. In part II of this series we discuss the detailed regional anatomy of the cardiac ganglia, phrenic nerve, and coronary venous system.

Exploration of Theoretical Ganglionated Plexi Ablation Technique in Atrial Fibrillation Surgery

“…The anatomic GP in the ILA area was close to the epicardial orifice of the coronary sinus. This area is distinguished from active GP in the inferior left PV in terms of the affected site to atrioventricular node conduction [17].…”

Left Atrial Appendage Exclusion for Atrial Fibrillation

“…15, 16, 19 It rests freely within the confines of the pericardial sac with the left phrenic nerve having a variable superimposed course as part of the pericardiophrenic neurovascular bundle. 26, 27 The ostium shares important relationships with the left superior pulmonary vein endocardially and the coronary vessels epicardially, with the left aortic sinus and main coronary artery lying posterior and medial, and the great cardiac vein and circumflex artery lying inferior. 19 The circumflex artery is usually less than 2mm from the LAA ostium.…”

HRS Policy Statement: Clinical Cardiac Electrophysiology Fellowship Curriculum: Update 2011

“… Anatomic structures, anatomic relationships and vascular supply 2-5 Conduction system (sinus node, intranodal pathways, AV node, His bundle and bundle branches, and Purkinje fibers)Venous anatomy (superior and inferior vena cava, coronary sinus and its branches, pulmonary veins)Anatomy of great vessels (right and left ventricular outflow tracts) including relationship to aortic sinuses of Valsalva and ostia of coronary arteriesAutonomic nervous system, ganglionic plexi, and phrenic nerve Resting membrane potential, action potential and passive membrane properties 2,6-10 Genesis of the resting potential in excitable cellsActive membrane propertiesCardiac action potentials (SA node, internodal tracts, atrial myocardium, AV node, bundle of His, bundle branches, Purkinje fibers, ventricular muscle)Passive membrane propertiesChannels and ionic currents responsible for the action potential (voltage operated, pump and exchange currents, ligand operated, mechanosensitive)Genes encoding for cardiac ion channels, exchangers, and pumpsElectrical heterogeneityMechanisms of automaticity in nodal and Purkinje pacemakersImpact of drugs Determinants of normal conduction 2 Structure and function of gap junctionsPassive membrane properties and electrotonic interactionsAnisotropyModulation of these factors by sympathetic and parasympathetic agonistsExcitability, supernormality and vulnerability Cellular basis for the inscription of the ECG 11,12 P waveQRST wave and ST segmentJ waveU wave Ion channels Voltage-gated ion channels 13 Ligand operated ion channels (include RyR) 14,15 Connexins 16 Regulation of ion channels in health and disease 17,18 Ion channels as targets for genetic arrhythmia syndromesIon channels as anti- and pro-arrhythmic drug targets 19,20 …”