Prognostic implications of QRS dispersion for major adverse cardiovascular events in asymptomatic women and men: the Multi-Ethnic Study of Atherosclerosis

Background QRS dispersion measured as the difference between maximal and minimal QRS duration in the standard 12-lead electrocardiogram has been shown to be associated with increased mortality in heart failure (HF) patients and increased arrhythmic events in patients with cardiomyopathy. Aims This study sought to examine the prognostic association between baseline QRS dispersion and future cardiovascular events in individuals without known prior cardiovascular disease. Methods The association of QRS dispersion with cardiovascular events was examined in 6510 MESA (Multi-Ethnic Study of Atherosclerosis) participants. Participants with bundle branch block were excluded. Study participants were divided into two groups based on the 95th percentile of QRS dispersion (QRS dispersion < 34 ms [group I] and QRS dispersion >= 34 ms [group II]). Cox proportional hazard models adjusting for demographic and clinical risk factors were used to examine the association of QRS dispersion with incident cardiovascular events (major adverse cardiovascular events [MACE]) and mortality. Analysis was repeated by forcing Framingham risk factors. Results Mean age was 62 +/- 10 years in group I and 63 +/- 10 years in group II (P = 0.02). QRS dispersion >= 34 ms was associated significantly with MACE (HR 1.30; 95% CI 1.04-1.62) and mortality (HR 1.33; 95% CI 1.03-1.73) after adjustment for cardiovascular risk factors and potential cofounders. Similar results were seen for mortality after adjustment for Framingham risk factors. Conclusion QRS dispersion >= 34 ms predicts cardiovascular events and mortality.