Long QT interval and CHD

Long QT interval related to high risk of CHD mortality

A long QT interval in the resting ECG was associated with a 4-fold 15-year CHD mortality risk in middle-aged men and a 3-fold 5-year risk in the elderly men of Zutphen. These associations could not be attributed to prevalent heart disease and were independent of other cardiovascular risk factors.

Interpretation

Middle-aged men in the general population having long QT syndrome were at greater risk of fatal CHD. Though few men in Zutphen had a clearly abnormal QT interval, risk increased gradually within the range of usual or normal values in the population.

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Smoking and cardiovascular disease

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