1. Reentrant and Focal Activations During Atrial Fibrillation in Patients With Atrial Septal Defect 
Takashi Nitta, MD, PhD, Shun-ichiro Sakamoto, MD, PhD, Yasuo Miyagi, MD, PhD, Masahiro Fujii, MD, PhD, Yosuke Ishii, MD, PhD, Masami Ochi, MD, PhD 
The Annals of Thoracic Surgery 
Volume 96, Issue 4, Pages (October 2013)
DOI: /j.athoracsur
Copyright © 2013 The Society of Thoracic Surgeons Terms and Conditions

2. Fig 1
Right atrium (RA) macroreentrant activation. The atrial epicardium was mapped for AF induced by burst pacing from the RA appendage in a 43-year-old man with a secundum atrial septal defect and paroxysmal AF for 3 years. Maps A, B, and C represent activation of lateral RA during time intervals A, B, and C indicated in ECG, respectively. Isochrones are demonstrated by color codes as indicated in lower panel. Repetitive activation appeared in lower RA between IVC and RV and propagated upward. The pattern of activation was unstable, and AF terminated spontaneously. (AF = atrial fibrillation; ECG = electrocardiogram; IVC = inferior vena cava; RPVs = right pulmonary veins; RV = right ventricle; SR = sinus rhythm; SVC = superior vena cava.)
The Annals of Thoracic Surgery  , DOI: ( /j.athoracsur )
Copyright © 2013 The Society of Thoracic Surgeons Terms and Conditions

3. Fig 2
Right atrium (RA) macroreentrant and left atrium (LA) focal activations: atrial activation maps in a 51-year-old man with a secundum ASD and long-standing persistent AF. Electrocardiogram with selected atrial electrograms and activation maps during four consecutive time intervals from A to D as indicated in upper panel. Maps show right posterior view of atria. Arrows indicate propagation of activation. Electrograms recorded at electrode locations from a to f on maps are shown in upper panel. A stable focal activation arose from posterior LA (a in maps) adjacent to the left PVs and, simultaneously, an unstable macroreentrant activation in the RA. Cycle length of posterior LA focal activation ranged from 154 ms to 166 ms (162 ± 5 ms), and activation interval at inferior RA between IVC and RV (e in maps) varied from 144 ms to 166 ms (158 ± 11 ms). RA macroreentrant activation represented a double-loop reentry with a transition between the lower RA reentry around IVC and counterclockwise activation of common atrial flutter. There was no interference between tachycardias during the observational period. (Ao = aorta; ECG = electrocardiogram; IVC = inferior vena cava; LPVs = left pulmonary veins; LV = left ventricle; MSEC = millisecond; RPVs = right pulmonary veins; SVC = superior vena cava.)
The Annals of Thoracic Surgery  , DOI: ( /j.athoracsur )
Copyright © 2013 The Society of Thoracic Surgeons Terms and Conditions

4. Fig 3
Reentrant and focal activations in the left atrium (LA). Atrial activation maps in a 68-year-old man with long-standing persistent AF and a secundum ASD. Maps show posterior view of atria; composition and format of figure are the same as in Figure 2. There was a reentrant activation around the LA appendage and a focal activation originating from the posterior LA. The reentrant activation around the LA appendage was stable, and average cycle length was 136 ± 3 ms (electrograms from a to e). Cycle length of posterior LA focal activation varied from 124 ms to 155 ms (142 ± 10 ms). The wave front of the focal activation propagated toward inferior LA. There was no interference between reentrant and focal activations during the observation period. RA was passively activated by the wave front propagating from LA across Bachmann’s bundle. (Ao = aorta; ECG = electrocardiogram; LAA = left atrial appendage; LPVs = left pulmonary veins; LV = left ventricle; MSEC = millisecond; PA = pulmonary artery; RPVs = right pulmonary veins; SVC = superior vena cava.)
The Annals of Thoracic Surgery  , DOI: ( /j.athoracsur )
Copyright © 2013 The Society of Thoracic Surgeons Terms and Conditions

5. Fig 4
Distribution of left atrium (LA) focal activations. A and B, left-superior and posterior views of atria, respectively. A total of six focal activation sites in LA determined in 5 patients with long-standing persistent atrial fibrillation (AF) are shown. Location of focal activations depicted as circular dots; gray dots indicate locations behind objects (LSPV and LIPV). One patient had two LA foci; no patient with paroxysmal AF had any LA focal activations. (Ao = aorta; IVC = inferior vena cava; LAA = left atrial appendage; LIPV = left inferior pulmonary vein; LSPV = left superior pulmonary vein; LV = left ventricle; PA = pulmonary artery; RAA = right atrial appendage; RIPV = right inferior pulmonary vein; RSPV = right superior pulmonary vein; SVC = superior vena cava.)
The Annals of Thoracic Surgery  , DOI: ( /j.athoracsur )
Copyright © 2013 The Society of Thoracic Surgeons Terms and Conditions