Quatrefoil reentry

Quatrefoil reentry is a type of cardiac arrhythmia that consists of two adjacent figure-of-eight reentrant circuits.

Quatrefoil reentry was predicted by bidomain simulations in 1991 [1] and observed experimentally in 1999. [2] Quatrefoil reentry can be induced by stimulating the heart through a single electrode twice, with the second stimulus timed near the end of the refractory period of the first action potential. If the second stimulus is a cathode, the wave fronts propagate initially parallel to the myocardial fibers; if it is an anode, the wave fronts propagate initially perpendicular to the fibers. Quatrefoil reentry can be understood qualitatively using a simple cellular automaton. [3]

References

  1. Roth BJ, Saypol JM (1991). "The formation of a re-entrant action potential wave front in tissue with unequal anisotropy ratios". International Journal of Bifurcation and Chaos 1: 927–928. doi:10.1142/S0218127491000671.
  2. Lin S-F, Roth BJ, Wikswo JP Jr (1999). "Quatrefoil reentry in myocardium: An optical imaging study of the induction mechanism". Journal of Cardiovascular Electrophysiology 10 (4): 574–586. doi:10.1111/j.1540-8167.1999.tb00715.x. PMID 10355700.
  3. Roth BJ (2002). "Virtual electrodes made simple: A cellular excitable medium modified for strong electrical stimuli". The Online Journal of Cardiology.