Sustained vortex-like waves in normal isolated ventricular muscle.

AUTOR(ES)

Davidenko, J M

RESUMO

Sustained reentrant excitation may be initiated in small (20 x 20 x less than 0.6 mm) preparations of normal ventricular muscle. A single appropriately timed premature electrical stimulus applied perpendicularly to the wake of a propagating quasiplanar wavefront gives rise to circulation of self-sustaining excitation waves, which pivot at high frequency (5-7 Hz) around a relatively small "phaseless" region. Such a region develops only very low amplitude depolarizations. Once initiated, most episodes of reentrant activity last indefinitely but can be interrupted by the application of an appropriately timed electrical stimulus. The entire course of the electrical activity is visualized with high temporal and spatial resolution, as well as high signal-to-noise ratio, using voltage-sensitive dyes and optical mapping. Two- and three-dimensional graphics of the fluorescence changes recorded by a 10 x 10 photodiode array from a surface of 12 x 12 mm provide sequential images (every msec) of voltage distribution during a reentrant vortex. The results suggest that two-dimensional vortex-like reentry in cardiac muscle is analogous to spiral waves in other biological and chemical excitable media.

Documentos Relacionados

• Large vortex-like structure of dipole field in computer models of liquid water and dipole-bridge between biomolecules
• Soluções tipo-vórtice de spins na fita de Möbius
• Vortex shedding as a precursor of turbulent electrical activity in cardiac muscle.
• Monoclonal antibodies detect a spectrin-like protein in normal and dystrophic human skeletal muscle.
• The consequences of simulated ischaemia on intracellular Ca2+ and tension in isolated ferret ventricular muscle.