Abstract
Recently, antipsychotic medications of the novel or atypical classes have received increased attention because of concerns with respect to potential lengthening of the QT interval, yet the currently available and commonly prescribed conventional antipsychotics are significantly more cardiotoxic, particularly agents in the butyrophenone and phenothiazine classes. Lengthening of the QT interval can be associated with a fatal paroxysmal ventricular arrhythmia known as torsades de pointes. The specific duration of the QT interval at which the risk of an adverse cardiac event is greatest, is not established. There is not only significant variation in the applied definition of an abnormal interval, but the maximal QT interval in healthy volunteers is greater than the currently accepted standards. The QT interval is influenced by normal physiological and pathologic factors, but the mechanisms remain unclear. Using recombinant technology, haloperidol and sertindole have been demonstrated to be high-affinity antagonists of a human cardiac potassium channel encoded by the human ether-a-go-go-related gene. Pimozide, however, has been shown to act principally through calcium channel antagonism, and chlorpromazine may affect sodium channels. Nevertheless, it is possible that these effects are significant only in the presence of predisposing factors, either genetic or acquired. Despite proven efficacy in clinical trials and subsequent supervised use in Europe, a number of recently developed antipsychotic medications are not available to patients in North America. Yet, conventional antipsychotic medications that would not be approved by current safety standards continue to be widely used.
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Selected References
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- Adamantidis M. M., Kerram P., Dupuis B. A. In vitro electrophysiological detection of iatrogenic arrhythmogenicity. Fundam Clin Pharmacol. 1994;8(5):391–407. doi: 10.1111/j.1472-8206.1994.tb00818.x. [DOI] [PubMed] [Google Scholar]
- Algra A., Tijssen J. G., Roelandt J. R., Pool J., Lubsen J. QT interval variables from 24 hour electrocardiography and the two year risk of sudden death. Br Heart J. 1993 Jul;70(1):43–48. doi: 10.1136/hrt.70.1.43. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bernardi M., Calandra S., Colantoni A., Trevisani F., Raimondo M. L., Sica G., Schepis F., Mandini M., Simoni P., Contin M. Q-T interval prolongation in cirrhosis: prevalence, relationship with severity, and etiology of the disease and possible pathogenetic factors. Hepatology. 1998 Jan;27(1):28–34. doi: 10.1002/hep.510270106. [DOI] [PubMed] [Google Scholar]
- Carella M. J., Mantz S. L., Rovner D. R., Willis P. W., 3rd, Gossain V. V., Bouknight R. R., Ferenchick G. S. Obesity, adiposity, and lengthening of the QT interval: improvement after weight loss. Int J Obes Relat Metab Disord. 1996 Oct;20(10):938–942. [PubMed] [Google Scholar]
- Cooke R. A., Chambers J. B., Singh R., Todd G. J., Smeeton N. C., Treasure J., Treasure T. QT interval in anorexia nervosa. Br Heart J. 1994 Jul;72(1):69–73. doi: 10.1136/hrt.72.1.69. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Drici M. D., Burklow T. R., Haridasse V., Glazer R. I., Woosley R. L. Sex hormones prolong the QT interval and downregulate potassium channel expression in the rabbit heart. Circulation. 1996 Sep 15;94(6):1471–1474. doi: 10.1161/01.cir.94.6.1471. [DOI] [PubMed] [Google Scholar]
- Drici M. D., Wang W. X., Liu X. K., Woosley R. L., Flockhart D. A. Prolongation of QT interval in isolated feline hearts by antipsychotic drugs. J Clin Psychopharmacol. 1998 Dec;18(6):477–481. doi: 10.1097/00004714-199812000-00011. [DOI] [PubMed] [Google Scholar]
- Drugs causing prolongation of QT interval and torsades de pointes. CMAJ. 1998 Jan 13;158(1):103-4, 107-8. [PubMed] [Google Scholar]
- Enyeart J. J., Dirksen R. T., Sharma V. K., Williford D. J., Sheu S. S. Antipsychotic pimozide is a potent Ca2+ channel blocker in heart. Mol Pharmacol. 1990 May;37(5):752–757. [PubMed] [Google Scholar]
- Gray V. S. Syncopal episodes associated with cisapride and concurrent drugs. Ann Pharmacother. 1998 Jun;32(6):648–651. doi: 10.1345/aph.17288. [DOI] [PubMed] [Google Scholar]
- Ishizaki F., Harada T., Yoshinaga H., Nakayama T., Yamamura Y., Nakamura S. [Prolonged QTc intervals in Parkinson's disease--relation to sudden death and autonomic dysfunction]. No To Shinkei. 1996 May;48(5):443–448. [PubMed] [Google Scholar]
- Jackson T., Ditmanson L., Phibbs B. Torsade de pointes and low-dose oral haloperidol. Arch Intern Med. 1997 Sep 22;157(17):2013–2015. [PubMed] [Google Scholar]
- Josefson D. Hay fever drug to be banned by the FDA. BMJ. 1997 Jan 25;314(7076):248–248. doi: 10.1136/bmj.314.7076.247c. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kon K., Krause E., Gögelein H. Inhibition of K+ channels by chlorpromazine in rat ventricular myocytes. J Pharmacol Exp Ther. 1994 Nov;271(2):632–637. [PubMed] [Google Scholar]
- Lawrence K. R., Nasraway S. A. Conduction disturbances associated with administration of butyrophenone antipsychotics in the critically ill: a review of the literature. Pharmacotherapy. 1997 May-Jun;17(3):531–537. [PubMed] [Google Scholar]
- Litherland S. Drug treatment and schizophrenia in the 1990s. Drugs. 1997 Nov;54(5):794–794. doi: 10.2165/00003495-199754050-00012. [DOI] [PubMed] [Google Scholar]
- Litherland S. Drug treatment and schizophrenia in the 1990s. Drugs. 1997 Nov;54(5):794–794. doi: 10.2165/00003495-199754050-00012. [DOI] [PubMed] [Google Scholar]
- Makkar R. R., Fromm B. S., Steinman R. T., Meissner M. D., Lehmann M. H. Female gender as a risk factor for torsades de pointes associated with cardiovascular drugs. JAMA. 1993 Dec 1;270(21):2590–2597. doi: 10.1001/jama.270.21.2590. [DOI] [PubMed] [Google Scholar]
- Molnar J., Zhang F., Weiss J., Ehlert F. A., Rosenthal J. E. Diurnal pattern of QTc interval: how long is prolonged? Possible relation to circadian triggers of cardiovascular events. J Am Coll Cardiol. 1996 Jan;27(1):76–83. doi: 10.1016/0735-1097(95)00426-2. [DOI] [PubMed] [Google Scholar]
- Moss A. J. Measurement of the QT interval and the risk associated with QTc interval prolongation: a review. Am J Cardiol. 1993 Aug 26;72(6):23B–25B. doi: 10.1016/0002-9149(93)90036-c. [DOI] [PubMed] [Google Scholar]
- Moss A. J. Prolonged QT-interval syndromes. JAMA. 1986 Dec 5;256(21):2985–2987. [PubMed] [Google Scholar]
- Nagy D., DeMeersman R., Gallagher D., Pietrobelli A., Zion A. S., Daly D., Heymsfield S. B. QTc interval (cardiac repolarization): lengthening after meals. Obes Res. 1997 Nov;5(6):531–537. doi: 10.1002/j.1550-8528.1997.tb00573.x. [DOI] [PubMed] [Google Scholar]
- Ochiai H., Kashiwagi M., Usui T., Oyama Y., Tokita Y., Ishikawa T. [Torsade de Pointes with T wave alternans in a patient receiving moderate dose of chlorpromazine: report of a case]. Kokyu To Junkan. 1990 Aug;38(8):819–822. [PubMed] [Google Scholar]
- Oka H., Mochio S., Sato H., Katayama K. Prolongation of QTc interval in patients with Parkinson's disease. Eur Neurol. 1997;37(3):186–189. doi: 10.1159/000117432. [DOI] [PubMed] [Google Scholar]
- Paoloni P., Ciliberti D., Blasi N., Capone P. Torsione di punta iatrogena indotta da tioridazina. Minerva Cardioangiol. 1992 Jun;40(6):245–249. [PubMed] [Google Scholar]
- Perkins D. O., Lieberman J. A. Medical complications and selectivity of therapeutic response to atypical antipsychotic drugs. Am J Psychiatry. 1998 Feb;155(2):272–276. doi: 10.1176/ajp.155.2.272. [DOI] [PubMed] [Google Scholar]
- Rampe D., Murawsky M. K., Grau J., Lewis E. W. The antipsychotic agent sertindole is a high affinity antagonist of the human cardiac potassium channel HERG. J Pharmacol Exp Ther. 1998 Aug;286(2):788–793. [PubMed] [Google Scholar]
- Ravin D. S., Levenson J. W. Fatal cardiac event following initiation of risperidone therapy. Ann Pharmacother. 1997 Jul-Aug;31(7-8):867–870. doi: 10.1177/106002809703100712. [DOI] [PubMed] [Google Scholar]
- Roden D. M., Lazzara R., Rosen M., Schwartz P. J., Towbin J., Vincent G. M. Multiple mechanisms in the long-QT syndrome. Current knowledge, gaps, and future directions. The SADS Foundation Task Force on LQTS. Circulation. 1996 Oct 15;94(8):1996–2012. doi: 10.1161/01.cir.94.8.1996. [DOI] [PubMed] [Google Scholar]
- Sawicki P. T., Dähne R., Bender R., Berger M. Prolonged QT interval as a predictor of mortality in diabetic nephropathy. Diabetologia. 1996 Jan;39(1):77–81. doi: 10.1007/BF00400416. [DOI] [PubMed] [Google Scholar]
- Scott J. L., Walls R. M. QT interval prolongation. J Emerg Med. 1985;3(3):221–225. doi: 10.1016/0736-4679(85)90076-9. [DOI] [PubMed] [Google Scholar]
- Sharma N. D., Rosman H. S., Padhi I. D., Tisdale J. E. Torsades de Pointes associated with intravenous haloperidol in critically ill patients. Am J Cardiol. 1998 Jan 15;81(2):238–240. doi: 10.1016/s0002-9149(97)00888-6. [DOI] [PubMed] [Google Scholar]
- Singh B. N. When is QT prolongation antiarrhythmic and when is it proarrhythmic? Am J Cardiol. 1989 Apr 1;63(12):867–869. doi: 10.1016/0002-9149(89)90059-3. [DOI] [PubMed] [Google Scholar]
- SoRelle R. Withdrawal of Posicor from market. Circulation. 1998 Sep 1;98(9):831–832. doi: 10.1161/01.cir.98.9.831. [DOI] [PubMed] [Google Scholar]
- Suessbrich H., Schönherr R., Heinemann S. H., Attali B., Lang F., Busch A. E. The inhibitory effect of the antipsychotic drug haloperidol on HERG potassium channels expressed in Xenopus oocytes. Br J Pharmacol. 1997 Mar;120(5):968–974. doi: 10.1038/sj.bjp.0700989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tentolouris N., Katsilambros N., Papazachos G., Papadogiannis D., Linos A., Stamboulis E., Papageorgiou K. Corrected QT interval in relation to the severity of diabetic autonomic neuropathy. Eur J Clin Invest. 1997 Dec;27(12):1049–1054. doi: 10.1046/j.1365-2362.1997.2300776.x. [DOI] [PubMed] [Google Scholar]
- Tran P. V., Hamilton S. H., Kuntz A. J., Potvin J. H., Andersen S. W., Beasley C., Jr, Tollefson G. D. Double-blind comparison of olanzapine versus risperidone in the treatment of schizophrenia and other psychotic disorders. J Clin Psychopharmacol. 1997 Oct;17(5):407–418. doi: 10.1097/00004714-199710000-00010. [DOI] [PubMed] [Google Scholar]
- Tsuang M. T., Faraone S. V. Genetic heterogeneity of schizophrenia. Seishin Shinkeigaku Zasshi. 1995;97(7):485–501. [PubMed] [Google Scholar]
- Warner J. P., Barnes T. R., Henry J. A. Electrocardiographic changes in patients receiving neuroleptic medication. Acta Psychiatr Scand. 1996 Apr;93(4):311–313. doi: 10.1111/j.1600-0447.1996.tb10653.x. [DOI] [PubMed] [Google Scholar]
- Wible B., Murawsky M. K., Crumb W. J., Jr, Rampe D. Stable expression and characterization of the human brain potassium channel Kv2.1: blockade by antipsychotic agents. Brain Res. 1997 Jun 27;761(1):42–50. doi: 10.1016/s0006-8993(97)00315-6. [DOI] [PubMed] [Google Scholar]
- Wise J. Hay fever drug to become prescription only. BMJ. 1997 May 3;314(7090):1299–1299. [PMC free article] [PubMed] [Google Scholar]
- Woosley R. L., Sale M. QT interval: a measure of drug action. Am J Cardiol. 1993 Aug 26;72(6):36B–43B. doi: 10.1016/0002-9149(93)90039-f. [DOI] [PubMed] [Google Scholar]
- Zareba W., Moss A. J., Schwartz P. J., Vincent G. M., Robinson J. L., Priori S. G., Benhorin J., Locati E. H., Towbin J. A., Keating M. T. Influence of genotype on the clinical course of the long-QT syndrome. International Long-QT Syndrome Registry Research Group. N Engl J Med. 1998 Oct 1;339(14):960–965. doi: 10.1056/NEJM199810013391404. [DOI] [PubMed] [Google Scholar]
- el-Gamal A., Gallagher D., Nawras A., Gandhi P., Gomez J., Allison D. B., Steinberg J. S., Shumacher D., Blank R., Heymsfield S. B. Effects of obesity on QT, RR, and QTc intervals. Am J Cardiol. 1995 May 1;75(14):956–959. doi: 10.1016/s0002-9149(99)80700-0. [DOI] [PubMed] [Google Scholar]
