Double irregular ventricular parasystole: rate-dependent entrance block and "supernormal" exit conduction.
نویسندگان
چکیده
An analysis of electrocardiograms from a patient with spontaneous double irregular ventricular parasystole is presented. Irregularity in one of the two parasystoles was produced by intermittence based on rate-dependent (phase 3) entrance block, and in the other parasystole it was attributed to "supernormal" exist conduction. Critical analysis of electrocardiograms revealed that first degree block, rate-dependent block, and "supernormal" conduction in the exit pathway may account for the alterations in the arrangement and manifestation of the parasystolic beats. An electrocardiographic approach to these properties of the parasystolic structure and demonstration of double ventricular parasystole with irregularity in both parasystoles has not previously been found in the literature.
منابع مشابه
Concealed ventricular parasystole uncovered in the form of ventricular escapes of variable coupling.
Exit block from a parasystolic focus is recognized when automatic discharges fail to become manifest during the excitable phase of the ventricular cycle. In the present study, an apparently complete exit block and a persistently concealed ventricular parasystole (VP) resulted from an exit refractory period (ExRP) longer than the sinus cycle length. Slowing of the heart rate caused the concealed...
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ورودعنوان ژورنال:
- Circulation
دوره 58 4 شماره
صفحات -
تاریخ انتشار 1978