Electrocardiographic QT interval prolongation and risk of primary cardiac arrest in diabetic patients.

Sudden cardiac death, also known as primary cardiac arrest (PCA), is a major cause of mortality among diabetic patients and typically occurs in the setting of coronary heart disease. Because it can occur as the first clinical manifestation of coronary heart disease, identifying diabetic patients at risk of PCA remains challenging. Interrelated sequelae of diabetes, including QT prolongation and autonomic failure (1,2), have been repeatedly implicated in the pathophysiology of PCA (3–6). However, it remains unknown whether the QT interval on a 12-lead electrocardiogram (ECG) has potential utility in risk stratification of diabetic patients without prior physiciandiagnosed heart disease for PCA (7–12).