Electropharmacologic effect of a standard dose of intravenous procainamide in patients with sustained ventricular tachycardia.
Clin Cardiol
; 23(3): 171-4, 2000 Mar.
Article
em En
| MEDLINE
| ID: mdl-10761804
BACKGROUND: Patients with inducible sustained ventricular tachycardia (VT) sometimes receive intravenous procainamide during electrophysiologic testing. Unfortunately, the responses to intravenous and subsequent oral drug therapy are variable and may be discordant. HYPOTHESIS: It was the aim of this study to determine whether this variability might be explained by heterogeneity in the electropharmacologic response, even in a homogeneous population. METHODS: We studied 42 patients who had spontaneous malignant ventricular arrhythmia and were inducible to sustained monomorphous VT during electrophysiologic testing. Each received 15 mg/kg of intravenous procainamide followed by a 2 mg/min infusion. Serum levels were drawn immediately following programmed stimulation. The mean procainamide level was 6.7 +/- 1.4 mcg/ml with an N-acetyl procainamide level of 1.0 +/- 0.5 mcg/ml. The 14 procainamide responders (5 of whom were noninducible and 9 whose VT cycle length increased > 100 ms) and the 28 nonresponders had similar procainamide and NAPA levels (6.5 +/- 1.4 vs. 6.7 +/- 1.4 mcg/ml). RESULTS: There was no significant difference in baseline clinical parameters, His to ventricular electrogram (HV) interval, effective refractory period, or VT cycle length. Prolongation of the effective refractory period and infra His conduction time occurred to a similar extent in responders and nonresponders. CONCLUSION: We conclude that procainamide has a consistent dose-response relationship with respect to refractoriness and conduction in patients with malignant arrhythmias. However, acute antiarrhythmic efficacy of procainamide cannot be predicted by clinical factors, drug levels, or drug-induced changes in common electrophysiologic parameters.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Procainamida
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Taquicardia Ventricular
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Sistema de Condução Cardíaco
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Antiarrítmicos
Tipo de estudo:
Prognostic_studies
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Clin Cardiol
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
Estados Unidos