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Síndrome do QT longo

Última revisión: 4 Feb 2026
Última actualización: 29 Aug 2023

Resumen

Definición

Anamnesis y examen

Principales factores de diagnóstico

  • história de mutação genética conhecida
  • uso de medicamentos ou circunstâncias conhecidos por aumentar o intervalo QT
  • síncope durante elevações do tônus adrenérgico
  • síncope durante excitação ou surpresa
  • sintomas arrítmicos pós-parto
  • síncope no repouso e durante bradicardia
  • síncope cardíaca
  • palpitações
  • paralisia periódica
  • características dismórficas
  • surdez neurossensorial
Todos los datos

Otros factores de diagnóstico

  • tontura
  • angina
  • fadiga
  • oligúria
  • fraqueza muscular
  • tetania
  • dormência
  • sinal de Chvostek
  • sinal de Trousseau
  • membros frios e pálidos
  • hipotensão
  • confusão
Todos los datos

Factores de riesgo

  • mutações no gene KCNQ1
  • mutações no gene KCNH2
  • mutações no gene SCN5A
  • medicamentos que prolongam o intervalo QT
  • hipocalemia
  • hipomagnesemia
  • hipocalcemia
  • bradiarritmias
  • lesões no sistema nervoso central
  • sexo feminino
  • desnutrição
Todos los datos

Pruebas diagnósticas

Primeras pruebas diagnósticas para solicitar

  • eletrocardiograma (ECG) para QTL1
  • eletrocardiograma (ECG) para QTL2
  • eletrocardiograma (ECG) para QTL3
  • eletrocardiograma (ECG) para hipocalemia e hipomagnesemia
  • eletrocardiograma (ECG) para hipocalcemia
  • Eletrocardiograma para bloqueio atrioventricular (AV) total
  • potássio sérico
  • magnésio sérico
  • cálcio sérico
Todos los datos

Pruebas diagnósticas que deben considerarse

  • monitor Holter
  • teste de tolerância ao exercício
  • ecocardiografia
  • teste genético
  • teste de adrenalina
Todos los datos

Algoritmo de tratamiento

Agudo

SQTL adquirida

síndrome do QT longo (SQTL) congênita sem evento cardíaco prévio

síndrome do QT longo (SQTL) congênita com evento cardíaco prévio

Colaboradores

Autores

Mehmet K. Aktas, MD, MBA

Associate Professor of Medicine

University of Rochester Medical Center

Rochester

NY

Divulgaciones

MKA declares that he has received research grants from Astra Zeneca, Medtronic, and Boston Scientific. MKA has served as consultant for Abbott and Huxley Medical. MKA holds a patent for ‘ECG Clock Electrocardiogram Based Diagnostic Device and Method’ (US patent #10,085,667). He is the author of a reference cited in this topic.

James P. Daubert, MD

Professor of Medicine

Duke University Medical Center

Duke Clinical Research Institute

Durham

NC

Divulgaciones

JPD declares that he has received honoraria for advisory boards, steering committees, data safety monitoring boards, events committees, and lecture fees from Abbott, Acutus Medical, Affera Inc., Biosense Webster, Biotronik, Boston Scientific, Farapulse, Gilead Sciences Inc., Medtronic, Microport, Phillips, and Vytronus; and research grants from Abbott, Biosense Webster, Boston Scientific, Farapulse, and Medtronic. He receives royalty payments from Wiley, Springboard and McGraw Hill for textbook authorship and educational materials. JPD declares that he has no stock, stock options, or other forms of ownership. He is the author of a reference cited in this topic.

Revisores por pares

Sami Viskin, MD

Director of Cardiac Hospitalization

Department of Cardiology

Tel Aviv Medical Center

Tel Aviv

Israel

Divulgaciones

SV declares that he has no competing interests.

Elizabeth S. Kaufman, MD

Associate Professor

Heart and Vascular Center

MetroHealth Campus

Case Western Reserve University

Cleveland

OH

Divulgaciones

ESK declares that she has no competing interests.

Agradecimiento de los revisores por pares

Los temas de BMJ Best Practice se actualizan de forma continua de acuerdo con los desarrollos en la evidencia y en las guías. Los revisores por pares listados aquí han revisado el contenido al menos una vez durante la historia del tema.

Divulgaciones

Las afiliaciones y divulgaciones de los revisores por pares se refieren al momento de la revisión.

Referencias

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Artículos principales

Zeppenfeld K, Tfelt-Hansen J, de Riva M, et al. 2022 ESC guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. Eur Heart J. 2022 Oct 21;43(40):3997-4126.Texto completo  Resumen

Priori SG, Wilde AA, Horie M, et al. HRS/EHRA/APHRS expert consensus statement on the diagnosis and management of patients with inherited primary arrhythmia syndromes. Heart Rhythm. 2013 Dec;10(12):1932-63.Texto completo  Resumen

Wilde AAM, Semsarian C, Márquez MF, et al. European Heart Rhythm Association (EHRA)/Heart Rhythm Society (HRS)/Asia Pacific Heart Rhythm Society (APHRS)/Latin American Heart Rhythm Society (LAHRS) expert consensus statement on the state of genetic testing for cardiac diseases. Europace. 2022 Sep 1;24(8):1307-67.Texto completo  Resumen

Roden DM. Clinical practice. Long-QT syndrome. N Engl J Med. 2008 Jan 10;358(2):169-76. Resumen

Al-Khatib SM, Stevenson WG, Ackerman MJ, et al. 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: a report of the American College of Cardiology/American Heart Association Task Force on clinical practice guidelines and the Heart Rhythm Society. Circulation. 2018 Sep 25;138(13):e272-391.Texto completo  Resumen

Sauer AJ, Moss AJ, McNitt S, et al. Long QT syndrome in adults. J Am Coll Cardiol. 2007 Jan 23;49(3):329-37. Resumen

Schwartz PJ, Moss AJ, Vincent GM, et al. Diagnostic criteria for the long QT syndrome. An update. Circulation. 1993 Aug;88(2):782-4. Resumen

Schwartz PJ, Crotti L. QTc behavior during exercise and genetic testing for the long-QT syndrome. Circulation. 2011 Nov 15;124(20):2181-4.Texto completo  Resumen

Artículos de referencia

Una lista completa de las fuentes a las que se hace referencia en este tema está disponible para los usuarios con acceso a todo BMJ Best Practice.
  • Síndrome do QT longo images
  • Diagnósticos diferenciais

    • Cardiopatia estrutural adquirida
    • Síncope neurocardiogênica (vasovagal)
    • Síncope neurológica
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  • Diretrizes

    • European Heart Rhythm Association (EHRA)/Heart Rhythm Society (HRS)/Asia Pacific Heart Rhythm Society (APHRS)/Latin American Heart Rhythm Society (LAHRS) Expert Consensus Statement on the state of genetic testing for cardiac diseases
    • 2022 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death
    Más Diretrizes
  • Folhetos informativos para os pacientes

    Ataque cardíaco: o que é?

    Ataque cardíaco: perguntas a fazer ao seu médico

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  • Calculadoras

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