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Inappropriate sinus tachycardia

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Synonyms and keywords: IST; chronic nonparoxysmal sinus tachycardia

Overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Inappropriate sinus tachycardia is an uncommon form of supraventricular tachycardia (SVT).

Epidemiology and Demographics

The condition was first formally recognized as a veritable syndrome in 1979.

Pathophysiology

The mechanism of the arrhythmia primarily involves the sinus node and peri-nodal tissue[1] and does not require the AV node for maintenance. These patients have no apparent heart disease or other causes of sinus tachycardia. IST is thought to be due to abnormal autonomic control or dysautonomia. An autoimmune mechanism has been suggested as several studies have detected autoantibodies that activate beta adrenoreceptors in a portion of patients.[2][3]

References

  1. Sato, Toshiaki; Mitamura, Hideo; Murata, Mitsushige; Shinagawa, Kaori; Miyoshi, Shunichiro; Kanki, Hideaki; Takatsuki, Seiji; Soejima, Kyoko; Miyazaki, Toshihisa (2000). “Electrophysiologic findings of a patient with inappropriate sinus tachycardia cured by selective radiofrequency catheter ablation”. Journal of Electrocardiology. 33 (4): 381–6. doi:10.1054/jelc.2000.9648. PMID 11099363.
  2. Chiale, Pablo A.; Garro, Hugo A.; Schmidberg, Jorge; Sánchez, Rubén A.; Acunzo, Rafael S.; Lago, Manuel; Levy, Gabriela; Levin, Mariano (2006). “Inappropriate sinus tachycardia may be related to an immunologic disorder involving cardiac β andrenergic receptors”. Heart Rhythm. 3 (10): 1182–6. doi:10.1016/j.hrthm.2006.06.011. PMID 17018348.
  3. Nattel, Stanley (2006). “Inappropriate sinus tachycardia and beta-receptor autoantibodies: A mechanistic breakthrough?”. Heart Rhythm. 3 (10): 1187–8. doi:10.1016/j.hrthm.2006.07.019. PMID 17018349.


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Historical Perspective

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

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Overview

The condition was first formally recognized as a veritable syndrome in 1979.

References


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Pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

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Overview

The mechanism of the arrhythmia primarily involves the sinus node and peri-nodal tissue[1] and does not require the AV node for maintenance. These patients have no apparent heart disease or other causes of sinus tachycardia. IST is thought to be due to abnormal autonomic control or dysautonomia. An autoimmune mechanism has been suggested as several studies have detected autoantibodies that activate beta adrenoreceptors in a portion of patients.[2][3]

References

  1. Sato, Toshiaki; Mitamura, Hideo; Murata, Mitsushige; Shinagawa, Kaori; Miyoshi, Shunichiro; Kanki, Hideaki; Takatsuki, Seiji; Soejima, Kyoko; Miyazaki, Toshihisa (2000). “Electrophysiologic findings of a patient with inappropriate sinus tachycardia cured by selective radiofrequency catheter ablation”. Journal of Electrocardiology. 33 (4): 381–6. doi:10.1054/jelc.2000.9648. PMID 11099363.
  2. Chiale, Pablo A.; Garro, Hugo A.; Schmidberg, Jorge; Sánchez, Rubén A.; Acunzo, Rafael S.; Lago, Manuel; Levy, Gabriela; Levin, Mariano (2006). “Inappropriate sinus tachycardia may be related to an immunologic disorder involving cardiac β andrenergic receptors”. Heart Rhythm. 3 (10): 1182–6. doi:10.1016/j.hrthm.2006.06.011. PMID 17018348.
  3. Nattel, Stanley (2006). “Inappropriate sinus tachycardia and beta-receptor autoantibodies: A mechanistic breakthrough?”. Heart Rhythm. 3 (10): 1187–8. doi:10.1016/j.hrthm.2006.07.019. PMID 17018349.


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Causes

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

The cause of inappropriate sinus tachycardia is unknown. It is a diagnosis of exclusion after all the specific physiological and psychological triggers of sinus tachycardia have been excluded. The diagnosis of IST is based on the presence of a persistent and recurrent sinus tachycardia on EKG that is otherwise unexplainable.

References


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Differentiating Inappropriate Sinus Tachycardia from other Diseases

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

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Differentiating Sinus Tachycardia from other Medical Conditions

The following medical conditions must be excluded as a cause of tachycardia:

References


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Epidemiology and Demographics

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

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Epidemiology and Demographics

The disorder is uncommon.

Age

Most patients are in their late 20s to early 30s.

Gender

More common in women.

References


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Diagnosis

Diagnosis

Diagnostic Criteria | History and Symptoms | Electrocardiogram

Treatment

Treatment

ACC/AHA/ESC Treatment Guidelines | Medical Therapy | Surgery

Case Studies

Case Studies

Case #1

Related Chapters



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