Short QT Syndrome
There is controversy whether short QT intervals are associated with sudden death. One trial found QTc intervals < 300ms to be associated with sudden death. However, a recent Finnish study in a random selection of healthy subjects (n=10 822) did not find an increased incidence of sudden death in patients with short QTc intervals. They defined QTc < 320ms as 'very short' and QTc < 340ms as 'short'. In total, 15 deaths occured in the group with QTc <340ms, with only one possible sudden death (cause of death unknown). They used Friderica's method for QTc correction: . They conclude that the ECG is not a good screening tool to find patients with a short QTc interval at risk of sudden death.
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