1. Volume 6, Issue 4, Pages 512-519 (April 2009)
Cardiac fatigue in long-distance runners is associated with ventricular repolarization abnormalities 
Anders Sahlén, MD, MRCP, Aigars Rubulis, MD, PhD, Reidar Winter, MD, PhD, Per-Herman Jacobsen, MD, Marcus Ståhlberg, MD, Per Tornvall, MD, PhD, FESC, Lennart Bergfeldt, MD, PhD, FESC, Frieder Braunschweig, MD, PhD, FESC 
Heart Rhythm 
Volume 6, Issue 4, Pages (April 2009)
DOI: /j.hrthm
Copyright © 2009 Heart Rhythm Society Terms and Conditions

2. Figure 1
Vectorcardiographic parameters. A: Televation describes the angle between the maximum T vector and a cranio-caudal axis perpendicular to the transverse (horizontal) plane, which is depicted by the rectangle (also in panel B). At 0° the vector points downward (caudally), and at 180° it points upward (cranially). B: Tazimuth describes the angle between the maximum T vector projected on the transverse plane and the left extreme of the X-axis. At 0° the vector points to the left. Forward motions of the vector (left-front-right) are defined as 0° to 180°, and backward motions of the vector (left-back-right) are defined as 0° to −180°. C: Tavplan (in μV) expresses the distortion (bulginess) of the T loop or its deviation from the preferential plane and is measured as the mean distance between the periphery of the loop and this plane. A “healthy” loop deviates little and therefore has a small Tavplan. D: Teigenvalue (dimensionless) expresses the shape and geometry of the T loop and is calculated as the ratio between the two highest diameters (d1/d2)2; d1 > d2. A “healthy” loop is elongated and has a high Teigenvalue. The figures in panels A, B, and D are reproduced from reference 9 with permission from Elsevier. The figure in panel C is reproduced with permission from Liliane Wecke, MD, PhD, Cardiac Memory in Two Human Models, doctoral thesis, Karolinska Institutet, Stockholm 2006.
Heart Rhythm 2009 6, DOI: ( /j.hrthm )
Copyright © 2009 Heart Rhythm Society Terms and Conditions

3. Figure 2
Electrical, biochemical and functional manifestations of cardiac fatigue. A: illustrates vectorcardiographic changes (ST-VM [solid line] and Tarea [interrupted line]). B: Biochemistry (NT-proBNP [solid line] and TnT [interrupted line]). C: Changes detected using echocardiography (stroke volume [solid line] and global strain [interrupted line]). *P <.05; **P <.01 from baseline.
Heart Rhythm 2009 6, DOI: ( /j.hrthm )
Copyright © 2009 Heart Rhythm Society Terms and Conditions

4. Figure 3
Cardiac electrical activity before and immediately after a 30-km race. A: Precordial activity based on vectorcardiographic data. B: T loops projected on the three orthogonal planes.
Heart Rhythm 2009 6, DOI: ( /j.hrthm )
Copyright © 2009 Heart Rhythm Society Terms and Conditions