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Correspondence  |   December 2005
Some Points Regarding Anesthesia for Patients with Congenital Long QT Syndrome
Author Notes
  • State University of New York at Stony Brook, Stony Brook, New York.
Article Information
Correspondence
Correspondence   |   December 2005
Some Points Regarding Anesthesia for Patients with Congenital Long QT Syndrome
Anesthesiology 12 2005, Vol.103, 1315-1316. doi:0000542-200512000-00033
Anesthesiology 12 2005, Vol.103, 1315-1316. doi:0000542-200512000-00033
To The Editor:AMPERSANDNUMBERSIGNx02014;
I read with great interest the article by Kies et al.  in the January 2005 issue of Anesthesiology entitled AMPERSANDNUMBERSIGNx0201C;Anesthesia for Patients with Congenital Long QT Syndrome.AMPERSANDNUMBERSIGNx0201D; The article is a good review of the subject, but it omits a number of important points regarding the perioperative care of patients with this disease. First, it should be noted that no studies exist comparing the safety of anesthetic agents in long QT syndrome (LQTS). The recommendations are therefore extrapolated from case reports and studies from healthy volunteers. Although isoflurane may indeed shorten the QT interval more than other agents, significant arrhythmias in LQTS patients anesthetized with isoflurane have been reported. A number of reports on this subject3, 4  have noted that the most prevalent factor associated with significant arrhythmias during surgery and anesthesia is the lack of control of symptoms before surgery. Although halothane and ketamine should probably be avoided, patients whose arrhythmias are well controlled before surgery rarely have arrhythmias during surgery, regardless of the anesthetic technique chosen.
Second, Kies et al.  do acknowledge that different genetic subtypes of LQTS are known to exist. However, optimal treatments of the various subtypes differ in important and significant ways. LQTS types 1 and 2 (LQT-1 and LQT-2) are defects on chromosomes 11 and 7, respectively, both encoding for potassium transmission. The standard treatment for both has been AMPERSANDNUMBERSIGNx03B2;-blockade. AMPERSANDNUMBERSIGNx03B2;-Blockade may, however, be contraindicated in LQT-3 (a defect in sodium transmission), because bradycardia in these patients can further prolong the QT interval and lead to ventricular arrhythmias. In 1991, Moss et al.  showed that cardiac pacing at a rate sufficient to shorten the QT interval could prove useful in LQTS. This article was written before the genetic subtypes of the condition were known, and the data of Schwartz et al.  suggest that cardiac pacing might be particularly useful in LQT-3.
Kies et al.  do mention the possibility of droperidol prolonging the QT interval. However, numerous drugs do the same and should probably be avoided in patients with LQTS. Those likely to be encountered in the operating room include amiodarone, disopyramide, chlorpromazine, dolasetron, haloperidol, tamoxifen, and many others.
Although genetic testing is still not easily obtainable, it should be noted that it is often possible to distinguish among the various subtypes of LQTS by the electrocardiographic pattern. LQT-1 has a prolonged QT interval with a normal to high T-wave amplitude, a broad-based T wave, and an indistinct T-wave onset. LQT-2 is characterized by a prolonged QT interval, low-amplitude T waves, and bifid T waves in more than 60% of cases. LQT-3 shows a prolonged QT interval with late onset, peaked T waves, and a long, isoelectric ST segment.
Last, despite all efforts, arrhythmic episodes, particularly torsade de pointes, are common in LQTS patients. Kies et al.  do not give specific recommendations for dealing with such arrhythmias when they occur, but intravenous magnesium; intravenous lidocaine; rapid-acting AMPERSANDNUMBERSIGNx03B2;-blocking medications, such as esmolol in LQT-1 and -2; and, in LQT-3 patients, cardiac pacing may be effective, and in all cases, the equipment for emergency electrical defibrillation should be present.
State University of New York at Stony Brook, Stony Brook, New York.
References
Kies SJ, Pabelick CM, Hurley HA, White RD, Ackerman MJ: Anesthesia for patients with congenital long QT syndrome. Anesthesiology 2005; 102:204AMPERSANDNUMBERSIGNx02013;10Kies, SJ Pabelick, CM Hurley, HA White, RD Ackerman, MJ
Peral A, Martinez MV, Garcia del Valle S, Carrera A: Two cases of anesthesia in long-QT syndrome. Rev Esp Anestesiol Reanim 2000; 42:193AMPERSANDNUMBERSIGNx02013;5Peral, A Martinez, MV Garcia del Valle, S Carrera, A
Katz RI, Quijano I, Barcelon N, Biancaniello T: Ventricular tachycardia during general anesthesia in a patient with congenital long QT syndrome. Can J Anaesth 2003; 50:398AMPERSANDNUMBERSIGNx02013;403Katz, RI Quijano, I Barcelon, N Biancaniello, T
O'Callaghan AC, Normandale JP, Morgan M: The prolonged Q-T syndrome: A review with anaesthetic implications and a report of two cases. Anaesth Intensive Care 1982; 10:50AMPERSANDNUMBERSIGNx02013;5O'Callaghan, AC Normandale, JP Morgan, M
Schwartz PJ, Priori SG, Locati EH, Napolitano C, Cantu F, Towbin JA, Keating MT, Hammoude H, Brown AM, Chen LS: Long QT syndrome patients with mutations of the SCN5A and HERG genes have differential responses to NaAMPERSANDNUMBERSIGNx0002B; channel blockade and to increases in heart rate. Circulation 1995; 92:3381AMPERSANDNUMBERSIGNx02013;96Schwartz, PJ Priori, SG Locati, EH Napolitano, C Cantu, F Towbin, JA Keating, MT Hammoude, H Brown, AM Chen, LS
Moss AJ, Liu JE, Gottlieb S, Locati EH, Schwartz PJ, Robinson JL: Efficacy of permanent pacing in the management of high-risk patients with long QT syndrome. Circulation 1991; 84:1524AMPERSANDNUMBERSIGNx02013;9Moss, AJ Liu, JE Gottlieb, S Locati, EH Schwartz, PJ Robinson, JL
Moss AJ: T-wave patterns associated with the hereditary long QT syndrome. Card Electrophysiol Rev 2002; 6:311AMPERSANDNUMBERSIGNx02013;15Moss, AJ