Diagnostic and prognostic value of the electrocardiogram in stable outpatients with type 2 diabetes

Abstract

Aims. The European Society of Cardiology guidelines on diabetes and cardiovascular disease (CVD) recommend an electrocardiogram (ECG) in patients with diabetes and hypertension or with suspected CVD. We investigated whether ECG abnormalities can be used as a diagnostic and prognostic marker of heart failure (HF) in patients with type-2 diabetes (T2D) in secondary care diabetes-clinics. Methods. We included 722 patients with T2D in sinus rhythm. HF with preserved ejection fraction (HFpEF) was defined according to the European Society of Cardiology guidelines. Heart failure with mid-range ejection fraction (HFmrEF) was patients with dyspnoea and an LVEF 41–49%. Heart failure with reduced ejection fraction (HFrEF) or asymptomatic left ventricular systolic dysfunction (ALVSD) was defined as a LVEF ≤40%. Results. Overall, 24% patients had ECG abnormalities. A total of 15% had HF whereof 48% had ECG abnormalities. A normal ECG had a 99.3% negative predictive value (NPV) of ruling out HFrEF/ALVSD. In a sub-group with 0-1 simple clinical risk markers, the ECG ruled out both HFrEF/ALVSD, HFmrEF, and HFpEF with an NPV of 96.6%. The hazard-ratio (HR) of incident CVD or death in patients with HF and a normal ECG compared with patients without HF was 1.85 [95%CI 1.01–3.39], p =.05, while an abnormal ECG increased the HR to 3.84 [2.33–6.33], p 99%.