Abstract

FUENMAYOR, Abdel J.; MILLAN, Miguel A.  and  FUENMAYOR P., Abdel M.. Variabilidad del intervalo de ciclo de las taquicardias ventriculares con igual morfología inducidas en estudio electrofisiológico. Rev. costarric. cardiol [online]. 2004, vol.6, n.1, pp.23-25. ISSN 1409-4142.

Introduction: Th e spontaneous variability in ventricular tachycardia cycle length should be known for the proper assessment of pharmacological treatment and anti-tachycardia devices programming. Objective: To assess the ventricular tachycardia (VT) rate variability of patients with re-entrant VTs induced in the electrophysiology laboratory. Methods: We included 22 patients (12 male) 52 + 18 years old, in whom 121 sustained monomorphic VTs could be induced (5.5 VT by patient). All VTs had the same ECG morphology in each patient and reentry was the mechanism of the VT. The majority of patients had idiopathic or chagasic dilated myocardiopathy. Results: Mean VT cycle length was 318 + 39 milliseconds (msec). The mean standard deviation of cycle length for all measured VT in one patient (inter-tachycardia variability) was 10.91 + 9.63. The average maximal - minimal cycle length of all VTs recorded in one patient (inter-tachycardia variability) was 26.15 msec. The mean standard deviation of the cycle length for one tachycardia (intra-tachycardia variability) was 5.78 + 2.4. No significant difference was found when cycle length variability was analyzed according to gender, etiology or patient’s age. Conclusion: VT rate variability is low in reentrants VTs induced in the same patient. The values should be taken into account when considering antiarrhythmic agent effects, antitachycardia pacing programming, and VT rate variability studies.

Keywords : Ventricular tachycardia; Cycle length; Variability.