Janeira L F
Section of Cardiac Electrophysiology, St. Mary's Medical Center, Evansville, IN 47714, USA.
Am Fam Physician. 1995 Oct;52(5):1447-53.
Torsades de pointes is a polymorphic form of ventricular tachycardia that is usually associated with prolongation of the QT interval. This QT prolongation may be either congenital or acquired. Etiologies for the acquired form include hypokalemia, hypomagnesemia, hypocalcemia, starvation, sick sinus syndrome, atrioventricular block and drug effects. Medications that have been implicated include most antiarrhythmic agents, some nonsedating histamine blockers, erythromycin and ketoconazole. Accurate and timely recognition of torsades de pointes is critically important because of the risk that traditional antiarrhythmic drug treatment will likely worsen the problem rather than improve it. Effective treatment requires withdrawal of any offending drugs or correction of the underlying cause of the QT prolongation. Beta blockers have been shown to be effective in preventing problems in congenitally at-risk patients. An implantable cardioverter defibrillator should be considered in some patients with recurrent episodes.
尖端扭转型室性心动过速是室性心动过速的一种多形性形式，通常与QT间期延长有关。这种QT间期延长可能是先天性的，也可能是后天获得性的。后天性形式的病因包括低钾血症、低镁血症、低钙血症、饥饿、病态窦房结综合征、房室传导阻滞和药物作用。与之相关的药物包括大多数抗心律失常药物、一些非镇静性组胺阻滞剂、红霉素和酮康唑。由于传统抗心律失常药物治疗可能会使问题恶化而非改善，因此准确及时地识别尖端扭转型室性心动过速至关重要。有效的治疗需要停用任何有问题的药物或纠正QT间期延长的潜在原因。已证明β受体阻滞剂对预防先天性高危患者出现问题有效。对于一些反复发作的患者，应考虑植入式心脏复律除颤器。
