Papers Published

1. AN Doshi, SF Idriss, Effect of resistive barrier location on the relationship between T-wave alternans and cellular repolarization alternans: a 1-D modeling study., Journal of electrocardiology, vol. 43 no. 6 (March, 2011), pp. 566-71 [doi] .
   (last updated on 2011/07/20)

   Abstract:
   Structural inhomogeneities in cardiac tissue have been associated with increased cellular repolarization alternans in animal experiments and increased T-wave alternans (TWA) in clinical studies. However, the effect of structural inhomogeneities on the relationship between cellular alternans and TWA has not been thoroughly investigated. We created 1-dimensional multicellular fiber models with and without a resistive barrier in various fiber regions and paced each model to induce cellular alternans. The models demonstrate that a resistive barrier in one fiber region substantially alters cellular repolarization alternans throughout the fiber. A midmyocardial or subepicardial barrier increase both TWA amplitude and maximum cellular alternans magnitude, relative to a fiber without a barrier. In addition, a direct relationship exists between TWA amplitude and maximum cellular alternans magnitude, which was highly dependent on barrier location. These results suggest that the position of a structural inhomogeneity within the myocardium may have substantial effects on dynamic repolarization instability and arrhythmogenicity.

   Keywords:
   Action Potentials* • Computer Simulation • Diagnosis, Computer-Assisted • Electrocardiography • Heart Conduction System • Humans • Models, Cardiovascular* • Myocytes, Cardiac* • Tachycardia, Ventricular • diagnosis • methods • methods* • physiopathology*