eMedicine Specialties > Cardiology > Arrhythmias

Torsade de Pointes: Differential Diagnoses & Workup

Author: Jatin Dave, MD, MPH, Instructor, Department of Medicine, Department of Internal Medicine, Division of Aging, Harvard Medical School; Staff Physician, Brigham and Women's Hospital
Coauthor(s): Revat Lakhia, MD, Visiting Staff, Department of Internal Medicine, Brigham and Women's Hospital; Graduate Student in Public Health, Department of Health Science, West Chester University of Pennsylvania
Contributor Information and Disclosures

Updated: Jul 30, 2009

Differential Diagnoses

Sudden Cardiac Death
Syncope
Ventricular Fibrillation
Ventricular Tachycardia

Other Problems to Be Considered

Acquired long QT syndrome versus congenital long QT syndrome

Torsade should be differentiated from polymorphic ventricular tachycardia, rarely monomorphic ventricular tachycardia, and supraventricular tachycardia with aberrant conduction. Hint: Atrial fibrillation may be intermixed with narrower and typical QRS complexes.

Workup

Laboratory Studies

  • Electrolytes: Check for hypokalemia, hypomagnesemia, and hypocalcemia.
  • Cardiac enzymes: Rule out myocardial ischemia, especially in patients without QT prolongation.

Imaging Studies

Chest radiographs and echocardiography should be performed to rule out structural heart disease if any clinical suggestion is present.

Other Tests

  • Electrocardiogram: Torsade is an electrocardiographic diagnosis, and obtaining an ECG is mandatory. The electrocardiographic features helpful in diagnosing torsade include its typical mode of onset and its morphology, as follows:
    • Patients have paroxysms of 5-20 beats, with a heart rate faster than 200 bpm; sustained episodes occasionally can be seen.
    • Progressive change in polarity of QRS about the isoelectric line occurs.
    • Complete 180° twist of QRS complexes in 10-12 beats is present.
    • Usually, a prolonged QT interval and pathological U waves are present, reflecting abnormal ventricular repolarization. The most consistent indicator of QT prolongation is a QT of 0.60 s or longer or a QTc (corrected for heart rate) of 0.45 s or longer.
    • A short-long-short sequence between the R-R interval occurs before the trigger response.
    • Patients may revert spontaneously or convert to a nonpolymorphic ventricular tachycardia or ventricular fibrillation.
    • Occasionally, T-wave alternans may be seen before torsade.
    • Torsade occurring in the setting of acquired long QT syndrome is preceded by pauses in almost all cases.
    • In congenital long QT syndrome (adrenergic-dependent), pause dependence is found in most of the adult cases while onset of torsade is not pause-dependent in children.
    • Failure to identify this rhythm may occur for various reasons. During very short runs of torsade, the typical twisting of the QRS complexes around the isoelectric line may not be apparent. Early events usually are short-lived.
    • In the case of a single-lead recording, the typical morphology of torsade may not be obvious.
    • The diagnosis of torsade should be considered in any patient with pause-dependent ventricular tachycardia, and ventricular bigeminy in a patient with long QT interval may be a sign of an impending torsade.
  • Findings from electrophysiological studies usually are negative in torsade.
  • Other tests should be ordered depending on the etiological factors being considered (see Causes).

More on Torsade de Pointes

Overview: Torsade de Pointes
Differential Diagnoses & Workup: Torsade de Pointes
Treatment & Medication: Torsade de Pointes
Follow-up: Torsade de Pointes
Multimedia: Torsade de Pointes
References
Further Reading
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References

  1. Noda T, Shimizu W, Satomi K, Suyama K, Kurita T, Aihara N. Classification and mechanism of Torsade de Pointes initiation in patients with congenital long QT syndrome. Eur Heart J. Dec 2004;25(23):2149-54. [Medline].

  2. Antzelevitch C, Sicouri S. Clinical relevance of cardiac arrhythmias generated by afterdepolarizations. Role of M cells in the generation of U waves, triggered activity and torsade de pointes. J Am Coll Cardiol. Jan 1994;23(1):259-77. [Medline].

  3. Nikolic G, Bishop RL, Singh JB. Sudden death recorded during Holter monitoring. Circulation. Jul 1982;66(1):218-25. [Medline].

  4. Lehmann MH, Timothy KW, Frankovich D, et al. Age-gender influence on the rate-corrected QT interval and the QT-heart rate relation in families with genotypically characterized long QT syndrome. J Am Coll Cardiol. Jan 1997;29(1):93-9. [Medline].

  5. Nguyen PT, Scheinman MM, Seger J. Polymorphous ventricular tachycardia: clinical characterization, therapy, and the QT interval. Circulation. Aug 1986;74(2):340-9. [Medline].

  6. Tzivoni D, Banai S, Schuger C, et al. Treatment of torsade de pointes with magnesium sulfate. Circulation. Feb 1988;77(2):392-7. [Medline].

  7. Kurita T, Ohe T, Shimizu W, et al. Early afterdepolarization in a patient with complete atrioventricular block and torsades de pointes. Pacing Clin Electrophysiol. Jan 1993;16(1 Pt 1):33-8. [Medline].

  8. Kocheril AG, Bokhari SA, Batsford WP, Sinusas AJ. Long QTc and torsades de pointes in human immunodeficiency virus disease. Pacing Clin Electrophysiol. Nov 1997;20(11):2810-6. [Medline].

  9. Attwell D, Cohen I, Eisner D, et al. The steady state TTX-sensitive ("window") sodium current in cardiac Purkinje fibres. Pflugers Arch. Mar 16 1979;379(2):137-42. [Medline].

  10. el-Sherif N, Caref EB, Yin H, Restivo M. The electrophysiological mechanism of ventricular arrhythmias in the long QT syndrome. Tridimensional mapping of activation and recovery patterns. Circ Res. Sep 1996;79(3):474-92. [Medline].

  11. Gintant GA, Datyner NB, Cohen IS. Slow inactivation of a tetrodotoxin-sensitive current in canine cardiac Purkinje fibers. Biophys J. Mar 1984;45(3):509-12. [Medline].

  12. Jackman WM, Friday KJ, Anderson JL, et al. The long QT syndromes: a critical review, new clinical observations and a unifying hypothesis. Prog Cardiovasc Dis. Sep-Oct 1988;31(2):115-72. [Medline].

  13. Justo D, Prokhorov V, Heller K, Zeltser D. Torsade de pointes induced by psychotropic drugs and the prevalence of its risk factors. Acta Psychiatr Scand. Mar 2005;111(3):171-6. [Medline].

  14. Kaplinsky E, Yahini JH, Barzilai J, Neufeld HN. Quinidine syncope; report of a case successfully treated with lidocaine. Chest. Dec 1972;62(6):764-6. [Medline].

  15. Kay GN, Plumb VJ, Arciniegas JG, et al. Torsade de pointes: the long-short initiating sequence and other clinical features: observations in 32 patients. J Am Coll Cardiol. Nov 1983;2(5):806-17. [Medline].

  16. Locati EH, Maison-Blanche P, Dejode P, et al. Spontaneous sequences of onset of torsade de pointes in patients with acquired prolonged repolarization: quantitative analysis of Holter recordings. J Am Coll Cardiol. Jun 1995;25(7):1564-75. [Medline].

  17. Roden DM. Drug-induced prolongation of the QT interval. N Engl J Med. Mar 4 2004;350(10):1013-22. [Medline].

  18. Roden DM, Lazzara R, Rosen M, et al. Multiple mechanisms in the long-QT syndrome. Current knowledge, gaps, and future directions. The SADS Foundation Task Force on LQTS. Circulation. Oct 15 1996;94(8):1996-2012. [Medline].

  19. Salle P, Rey JL, Bernasconi P, et al. [Torsades de pointe. Apropos of 60 cases]. Ann Cardiol Angeiol (Paris). Jun 1985;34(6):381-8. [Medline].

  20. Tan HL, Hou CJ, Lauer MR, Sung RJ. Electrophysiologic mechanisms of the long QT interval syndromes and torsade de pointes. Ann Intern Med. May 1 1995;122(9):701-14. [Medline].

  21. Taylor D. Psychotropic drugs, torsade de pointes and sudden death. Acta Psychiatr Scand. Mar 2005;111(3):169-70. [Medline].

  22. Vitelli LL, Crow RS, Shahar E, et al. Electrocardiographic findings in a healthy biracial population. Atherosclerosis Risk in Communities (ARIC) Study Investigators. Am J Cardiol. Feb 15 1998;81(4):453-9. [Medline].

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Further Reading

Related guidelines

ACC/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices).

(1) ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to revise the 1999 guidelines for the Management of Acute Myocardial Infarction). (2) 2007 focused update of the ACC/AHA 2004 guidelines for the management of patients with ST-elevation myocardial infarction. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.

Practice standards for electrocardiographic monitoring in hospital settings: an American Heart Association scientific statement from the Councils on Cardiovascular Nursing, Clinical Cardiology, and Cardiovascular Disease in the Young.

ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation).

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Keywords

torsade de pointes, quinidine syncope, polymorphic ventricular tachycardia, VT, prolonged QT interval, arrhythmia, TdP, torsade de pointes ventricular tachycardia, TdPVT, ventricular fibrillation, early after depolarization, EAD, afterdepolarization, arrhythmia, torsades de pointes, torsades, torsade, sudden cardiac death, SCD, sudden death, ventricular fibrillation, tachyarrhythmia

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Contributor Information and Disclosures

Author

Jatin Dave, MD, MPH, Instructor, Department of Medicine, Department of Internal Medicine, Division of Aging, Harvard Medical School; Staff Physician, Brigham and Women's Hospital
Jatin Dave, MD, MPH is a member of the following medical societies: American College of Physicians-American Society of Internal Medicine, American Geriatrics Society, American Medical Association, and Society of General Internal Medicine
Disclosure: Nothing to disclose.

Coauthor(s)

Revat Lakhia, MD, Visiting Staff, Department of Internal Medicine, Brigham and Women's Hospital; Graduate Student in Public Health, Department of Health Science, West Chester University of Pennsylvania
Revat Lakhia, MD is a member of the following medical societies: Medical Council of India
Disclosure: Nothing to disclose.

Medical Editor

Justin D Pearlman, MD, PhD, ME, MA, Director of Advanced Cardiovascular Imaging, Professor of Medicine, Professor of Radiology, Adjunct Professor, Thayer Bioengineering and Computer Science, Dartmouth-Hitchcock Medical Center
Justin D Pearlman, MD, PhD, ME, MA is a member of the following medical societies: American College of Cardiology, American College of Physicians, American Federation for Medical Research, International Society for Magnetic Resonance in Medicine, and Radiological Society of North America
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Brian Olshansky, MD, Professor of Medicine, Department of Internal Medicine, University of Iowa College of Medicine
Brian Olshansky, MD is a member of the following medical societies: American Autonomic Society, American College of Cardiology, American College of Chest Physicians, American College of Physicians, American College of Sports Medicine, American Federation for Clinical Research, American Heart Association, Cardiac Electrophysiology Society, Heart Rhythm Society, and New York Academy of Sciences
Disclosure: Guidant/Boston Scientific Honoraria Speaking and teaching; Medtronic Honoraria Speaking and teaching; Guidant/Boston Scientific Consulting fee Consulting; Reliant Grant/research funds Other; Novartis Honoraria Speaking and teaching; Novartis Consulting fee Consulting

CME Editor

Amer Suleman, MD, Consultant in Electrophysiology and Cardiovascular Medicine, Department of Internal Medicine, Division of Cardiology, Medical City Dallas Hospital
Amer Suleman, MD is a member of the following medical societies: American College of Physicians, American Heart Association, American Institute of Stress, American Society of Hypertension, Federation of American Societies for Experimental Biology, Royal Society of Medicine, and Society of Cardiac Angiography and Interventions
Disclosure: Nothing to disclose.

Chief Editor

Jeffrey N Rottman, MD, Professor of Medicine and Pharmacology, Director, Clinical Cardiac Electrophysiology Fellowship Program, Vanderbilt University School of Medicine; Chief, Department of Cardiology, Nashville Veterans Affairs Medical Center
Jeffrey N Rottman, MD is a member of the following medical societies: American Heart Association and North American Society of Pacing and Electrophysiology (NASPE)
Disclosure: Nothing to disclose.

 
 
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