title: Simultaneous epicardial and noncontact endocardial mapping of the canine right atrium: simulation and experiment.
abstract: Epicardial high-density electrical mapping is a well-established experimental instrument to monitor in vivo the activity of the atria in response to modulations of the autonomic nervous system in sinus rhythm. In regions that are not accessible by epicardial mapping, noncontact endocardial mapping performed through a balloon catheter may provide a more comprehensive description of atrial activity. We developed a computer model of the canine right atrium to compare epicardial and noncontact endocardial mapping. The model was derived from an experiment in which electroanatomical reconstruction, epicardial mapping (103 electrodes), noncontact endocardial mapping (2048 virtual electrodes computed from a 64-channel balloon catheter), and direct-contact endocardial catheter recordings were simultaneously performed in a dog. The recording system was simulated in the computer model. For simulations and experiments (after atrio-ventricular node suppression), activation maps were computed during sinus rhythm. Repolarization was assessed by measuring the area under the atrial T wave (ATa), a marker of repolarization gradients. Results showed an epicardial-endocardial correlation coefficients of 0.80 and 0.63 (two dog experiments) and 0.96 (simulation) between activation times, and a correlation coefficients of 0.57 and 0.46 (two dog experiments) and 0.92 (simulation) between ATa values. Despite distance (balloon-atrial wall) and dimension reduction (64 electrodes), some information about atrial repolarization remained present in noncontact signals.
authors.affiliation: Département de Physiologie, Université de Montréal, Montréal, Québec, Canada; Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada.
authors.forename: Sepideh
authors.initials: S
authors.lastname: Sabouri
authors.affiliation: Département de Physiologie, Université de Montréal, Montréal, Québec, Canada; Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada.
authors.forename: Elhacene
authors.initials: E
authors.lastname: Matene
authors.affiliation: Département de Physiologie, Université de Montréal, Montréal, Québec, Canada; Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada.
authors.forename: Alain
authors.initials: A
authors.lastname: Vinet
authors.affiliation: Conseil National de Recherche Canada, Montréal, Québec, Canada.
authors.forename: Louis-Philippe
authors.initials: LP
authors.lastname: Richer
authors.affiliation: Département de Physiologie, Université de Montréal, Montréal, Québec, Canada; Département de Pharmacologie, Université de Montréal, Montréal, Québec, Canada.
authors.forename: René
authors.initials: R
authors.lastname: Cardinal
authors.affiliation: Department of Pharmacology, East Tennessee State University, Johnson City, Tennessee, United States of America.
authors.forename: J Andrew
authors.initials: JA
authors.lastname: Armour
authors.affiliation: Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada; Département de Chirurgie, Université de Montréal, Montréal, Québec, Canada.
authors.forename: Pierre
authors.initials: P
authors.lastname: Pagé
authors.affiliation: Département de Physiologie, Université de Montréal, Montréal, Québec, Canada; Département de Pharmacologie, Université de Montréal, Montréal, Québec, Canada.
authors.forename: Teresa
authors.initials: T
authors.lastname: Kus
authors.affiliation: Département de Physiologie, Université de Montréal, Montréal, Québec, Canada; Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada.
authors.forename: Vincent
authors.initials: V
authors.lastname: Jacquemet
mesh_terms: D000818:Animals; D016275:Atrial Function / Q000502:physiology*; D003198:Computer Simulation; D004285:Dogs; D004562:Electrocardiography; D004566:Electrodes; D004699:Endocardium / Q000033:anatomy & histology* / Q000502:physiology*; D056149:Epicardial Mapping / Q000379:methods*; D006325:Heart Atria / Q000033:anatomy & histology*; D013997:Time Factors