paroxysmal tachycardia n tachycardia that begins and ends abruptly and that is initiated by a premature supraventricular beat originating in the atrium or in the atrioventricular node or bundle of His or by a premature ventricular beat
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attacks of tachycardia having sudden onset and cessation; it is usually qualified by the locus of impulse origin as either ventricular or supraventricular. Some classifications subdivide the latter into atrial and junctional tachycardias.Medical dictionary. 2011.