Abstract 11036: Arrhythmia Risk Profiles in Patients with Coronary Artery Disease: The Influence of Diabetes

Abstract

Background: Patients with diabetes (DM) are known to have a higher risk of sudden cardiac death. Recently, two non-invasive arrhythmia risk markers, heart rate turbulence (HRT) and T-wave alternans (TWA) measured from Holter recordings and/or exercise ECG, have emerged as powerful predictors of fatal or near-fatal arrhythmia events in patients with coronary artery disease (CAD). We assessed the relationship of DM with abnormal HRT+TWA in two independent CAD patient cohorts.

Methods and Results: HRT & TWA were measured in the ARTEMIS risk stratification study that includes a broad group of CAD patients with (n=526) and without DM (n=475). Risk assessment was performed 3-12 months after coronary angiography. The REFINE-ICD study randomizes post-infarction (MI) patients with ejection fraction (EF) values between 36%-49% and abnormal HRT+TWA measured 2-12 months post-MI to ICD vs. conventional therapy. In the ARTEMIS cohort, abnormal HRT+TWA was more common in DM (125/526, 24%) vs. non-DM patients (63/475, 13%; p<0.001). Similarly, the prevalence of abnormal HRT+TWA in the initial 116 patients screened in REFINE-ICD was more common in DM (21/36, 58%) vs. non-DM patients (19/80, 24%; p=0.001). In ARTEMIS abnormal HRT+TWA was more common in patients with an EF <50% (28%) vs. ≥50% (18%; p<0.001).

Conclusions: An abnormal arrhythmia risk profile was more common in CAD patients with DM, particularly in patients with mild-to moderate impairment of left ventricular function. This observation may explain the higher risk of arrhythmia-related death associated with DM. Ongoing data collection and outcomes assessment in these and other studies will aid in clarifying the role of these non-invasive arrhythmia risk markers.