Jalife J

Language: Spanish
References: 11
Page: 175-177
PDF size: 87.39 Kb.

ABSTRACT

The hereditary disease known as polymorphic catecholaminergic ventricular tachycardia (PCVT) is highly lethal. Almost 30% of the affected patients die before 40 years old, mainly due to sudden cardiac death. We have used isolated hearts from mutant mice (type 2 ryanodine receptors, RyR2/RyR2^R4496C) to investigate arrhythmia mechanisms that are adrenergic- and intracellular calcium ([Ca²⁺]_o) levels-dependent. Our results corroborate that polymorphic and bidirectional ventricular arrhythmias, as well as ventricular fibrillation, occurs in 50% of RyR2/RyR2^R4496C mice, and in less than 12% of the non-affected mice. Our hypothesis suggests that the origin of catecholaminergic arrhythmias in animals, and possibly in humans, is conditioned by the focal activity that begins by late post-potentials in the Purkinje fibers.

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