High prevalence of exercise-induced arrhythmias in catecholaminergic polymorphic ventricular tachycardia mutation-positive family members diagnosed by cascade genetic screening.
Europace
; 12(3): 417-23, 2010 Mar.
Article
en En
| MEDLINE
| ID: mdl-20106799
ABSTRACT
AIM:
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited cardiac disease predisposing to life-threatening arrhythmias. We aimed to determine the prevalence of arrhythmias and efficacy of beta-blocker treatment in mutation-positive family members diagnosed by cascade genetic screening. METHODS ANDRESULTS:
Relatives of six unrelated CPVT patients were tested for the relevant mutation in the ryanodine receptor-2 gene. Mutation carriers underwent an exercise test at inclusion time and 3 months after the initiation of beta-blocker therapy in the highest tolerable dose. The occurrence of ventricular premature beats, couplets, and non-sustained ventricular arrhythmias (nsVT) were recorded in addition to the heart rate at which they occurred. Thirty family members were mutation carriers and were followed for 22 (13-288) months. Previous undiagnosed CPVT-related symptoms were reported by eight subjects. Exercise test induced ventricular arrhythmias in 23 of the 30 mutation carriers. On beta-blocker treatment, exercise-induced arrhythmias occurred at a lower heart rate (117 +/- 17 vs. 135 +/- 34 beats/min, P = 0.02) but at similar workload (P = 0.78). Beta-blocker treatment suppressed the occurrence of exercise-induced nsVT in three of the four patients, while less severe arrhythmias were unchanged. One patient died during follow-up.CONCLUSION:
Exercise test revealed a high prevalence of arrhythmias in CPVT mutation carriers diagnosed by cascade genetic screening. beta-Blocker therapy appeared to suppress the most severe exercise-induced arrhythmias, while less severe arrhythmias occurred at a lower heart rate.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Ejercicio Físico
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Catecolaminas
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Taquicardia Ventricular
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Canal Liberador de Calcio Receptor de Rianodina
Tipo de estudio:
Diagnostic_studies
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Prevalence_studies
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Risk_factors_studies
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Screening_studies
Límite:
Adolescent
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Adult
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Aged
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Child
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Año:
2010
Tipo del documento:
Article