title: Quantification of the transmural dynamics of atrial fibrillation by simultaneous endocardial and epicardial optical mapping in an acute sheep model.
abstract: BACKGROUND
  Therapy strategies for atrial fibrillation based on electric characterization are becoming viable personalized medicine approaches to treat a notoriously difficult disease. In light of these approaches that rely on high-density surface mapping, this study aims to evaluate the presence of 3-dimensional electric substrate variations within the transmural wall during acute episodes of atrial fibrillation.
  
  
  RESULTS
  Optical signals were simultaneously acquired from the epicardial and endocardial tissue during acute fibrillation in ovine isolated left atria. Dominant frequency, regularity index, propagation angles, and phase dynamics were assessed and correlated across imaging planes to gauge the synchrony of the activation patterns compared with paced rhythms. Static frequency parameters were well correlated spatially between the endocardium and the epicardium (dominant frequency, 0.79 ± 0.06 and regularity index, 0.93 ± 0.009). However, dynamic tracking of propagation vectors and phase singularity trajectories revealed discordant activity across the transmural wall. The absolute value of the difference in the number, spatial stability, and temporal stability of phase singularities between the epicardial and the endocardial planes was significantly >0 with a median difference of 1.0, 9.27%, and 19.75%, respectively. The number of wavefronts with respect to time was significantly less correlated and the difference in propagation angle was significantly larger in fibrillation compared with paced rhythms.
  
  
  CONCLUSIONS
  Atrial fibrillation substrates are dynamic 3-dimensional structures with a range of discordance between the epicardial and the endocardial tissue. The results of this study suggest that transmural propagation may play a role in atrial fibrillation maintenance mechanisms.
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Sarah R
authors.initials: SR
authors.lastname: Gutbrod
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Richard
authors.initials: R
authors.lastname: Walton
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Stephen
authors.initials: S
authors.lastname: Gilbert
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Valentin
authors.initials: V
authors.lastname: Meillet
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Rémi
authors.initials: R
authors.lastname: Dubois
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.).
authors.forename: Olivier
authors.initials: O
authors.lastname: Bernus
authors.affiliation: From the Department of Biomedical Engineering, Washington University in Saint Louis, MO (S.R.G., I.R.E.); L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Université de Bordeaux, France (S.R.G., R.W., S.G., V.M., P.J., M.H., M.H., R.D., O.B., I.R.E.); Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); Université de Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France (R.W., V.M., P.J., M.H., M.H., R.D., O.B.); CHU de Bordeaux, Hôpital du Haut Lévêque, Pessac, France (V.M., P.J., M.H., M.H.); and Max Delbrück Center for Molecular Medicine, Berlin, Germany (S.G.). efimov@gwu.edu.
authors.forename: Igor R
authors.initials: IR
authors.lastname: Efimov
mesh_terms: D000200:Action Potentials; D000208:Acute Disease; D000818:Animals; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology; D016279:Atrial Function, Left; D004195:Disease Models, Animal; D004699:Endocardium / Q000503:physiopathology*; D056149:Epicardial Mapping; D005240:Feasibility Studies; D006325:Heart Atria / Q000503:physiopathology*; D010496:Pericardium / Q000503:physiopathology*; D011237:Predictive Value of Tests; D012756:Sheep; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors
keywords: atrial fibrillation; electrophysiology; reentry; rotor