Figure 7.
An example of an irregular tachygastria defined by HR mapping, due to unstable ectopic events arising at multiple locations (stars; duration >200 seconds). The activity was mapped from the same patient and in the same location as that shown in Figure 6. Isochronal maps of 5 representative cycles (isochronal intervals = 1 s) showing chaotic tissue activation and wave collisions, resulting in a range or frequencies across the mapped field (1.4 –5.7 cpm). From O’Grady G, Angeli T, Du P et al. Abnormal initiation and conduction of slow wave activity in gastroparesis, defined by high-resolution electrical mapping. Gastroenterology. 2012;143:589–598; with permission.