Body surface distribution of T wave alternans is modulated by heart rate and ventricular activation sequence in patients with cardiomyopathy - Fig 7

Illustration of TWA magnitude attenuation (lower panel) associated with increasing atrioventricular pacing rate (upper panel) in a precordial lead of a representative patient. The TWA magnitude decreases by ~1.5 uV with each subsequent 10 bpm increase in rate, causing TWA magnitude to fall below clinical significance at 120 bpm. The red shaded regions indicate V_alt values with a k ≥3. The dotted black line denotes the clinical TWA V_alt cutpoint of 1.9 uV.