The first description of repolarization consequences of fever was in LQT2 where repeated episodes of fever-induced TdP occurred in two related LQT2 patients (father and son) with the A558P mutation in KCNH2. 10 The A558P mutant proteins were further characterized as having a dominant-negative effect on intracellular trafficking of normal Kv11.1 proteins and in reducing the temperature-dependent increases in normal Kv11.1 current, further upsetting the balance between depolarizing and repolarizing currents in favor of depolarization.2 Here, KCNH2 is linked to torsades de pointes.