Long QT Syndrome

Cardiology

Prolonged ventricular repolarisation → torsades and SCD risk.

Causes

  • Congenital (LQT1-15; LQT1 most common)
  • Acquired: drugs (quinolones, macrolides, antipsychotics, antifungals), electrolytes (↓K, Mg, Ca), hypothyroidism

Diagnosis

  • QTc >460 ms F / >450 ms M (Bazett); >500 high risk
  • Schwartz score for congenital

Management

  • Avoid triggers (LQT1: exercise/swim; LQT2: startle/postpartum; LQT3: rest)
  • β-blocker (nadolol preferred)
  • ICD if aborted SCD/syncope on β-blocker
  • Correct electrolytes; withdraw offending drugs

Related in WardRound

Educational — verify locally.

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