What is the classic triad of Andersen-Tawil syndrome?

Andersen-Tawil syndrome triad: (1) periodic paralysis (hypo/hyperkalemic), (2) ventricular arrhythmias (bidirectional VT, PVCs), (3) dysmorphic features (hypertelorism, low-set ears, clinodactyly).

Why is QU prolongation significant?

In Andersen-Tawil, the apparent QT prolongation is largely QU prolongation due to giant U-waves from KCNJ2 (Kir2.1) dysfunction. True QTc may be less prolonged than it appears.

How is Andersen-Tawil treated?

Acetazolamide reduces paralytic episodes. Beta-blockers and flecainide address arrhythmias. KCNJ2 variant-specific therapy is emerging. Potassium supplementation helps during hypokalemic paralysis.

Andersen-Tawil QU Interval

Identify Andersen-Tawil syndrome (LQT7) by characteristic prolonged QU interval, prominent U-waves, bidirectional VT, periodic paralysis, and dysmorphic features.

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