Abstract 14417: Association of QRS Duration with MRI Measures of Left Ventricular Structure and Function and Risk of Heart Failure in Middle-Aged and Older Adults: the Multi-Ethnic Study of Atherosclerosis (MESA)
Background: Prolonged QRS duration (QRSd) on the resting 12-lead ECG has been associated with incident heart failure (HF). Left ventricular (LV) structural and functional measures also are associated with incident HF. Whether QRSd, a marker of electrical and myocardial impulse propagation, is associated with incident HF independent of LV structure and function is unknown.
Methods: We included participants who were 45-84 year old men and women free of cardiovascular disease from 4 race/ethnic groups in the NHLBI-funded MESA Study, and who had baseline ECG and cardiac MRI data available. We examined the association of QRSd with incident hospitalized HF over 5.5 years, unadjusted and after adjustment for demographic and clinical variables and each MRI LV measure of structure and function (separately).
Results: A total of 4,621 participants were included (50.9% women; 26.2% black, 22.3% Hispanic, 12.5% Chinese; mean age 61.3 years); 84 participants developed incident HF. QRSd ≥ 100 msec was associated with incident HF (unadjusted hazards ratio 2.44, p<0.001; see Table). The association of QRSd with incident HF was attenuated to non-significance by adjustment for MRI measures of LV structure (LVEDV, LVESV, LV mass), but not by LV functional measures (EF, stroke volume), or demographic and clinical risk factors. Findings were similar when we considered QRSd as a continuous variable.
Conclusion: Prolonged QRS duration was associated with incident HF in this middle-aged and older multiracial cohort. The association was substantially attenuated by adjustment for MRI measures of LV structure, but not by measures of LV function or demographic or clinical risk factors. Prolonged QRS duration may thus be a useful marker of subclinical LV structural remodeling and risk for HF. Further research is warranted to elucidate the mechanisms underlying these associations.
- © 2010 by American Heart Association, Inc.