Author + information
- Received March 16, 2016
- Revision received July 25, 2016
- Accepted July 28, 2016
- Published online January 2, 2017.
- Akshay Goel, MDa,
- Christopher D. Maroules, MDa,
- Gary F. Mitchell, MDb,
- Ronald Peshock, MDa,c,
- Colby Ayers, MSd,
- Roderick McColl, PhDa,
- Wanpen Vongpatanasin, MDc,∗∗ ( and )
- Kevin S. King, MDe,∗ ()
- aDepartment of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas
- bCardiovascular Engineering, Inc., Norwood, Massachusetts
- cCardiology Division, University of Texas Southwestern Medical Center, Dallas, Texas
- dDepartment of Clinical Science, University of Texas Southwestern Medical Center, Dallas, Texas
- eHuntington Medical Research Institutes, Pasadena, California
Objectives This study aims to compare ethnic difference in proximal aortic pulse wave velocity (PWV) and characteristic impedance (Zc).
Background Increased aortic stiffness is an independent predictor of target organ damage, incident hypertension, and all-cause mortality. However, previous studies have not directly assessed proximal aortic function in Blacks, the ethnic population with disproportionately high risk for incident hypertension and target organ complications.
Methods We evaluated the multiethnic, population-based DHS (Dallas Heart Study) participants (N = 2,544, 54.2% women, 49.7% Black) who underwent cardiac magnetic resonance at 1.5-T. Aortic stiffness and Zc were determined from aortic arch PWV and lumen area measurements. Linear regression was used to evaluate ethnic differences in proximal aortic wall stiffness using aortic arch PWV and Zc as dependent variables with and without adjustment for traditional cardiovascular risk factors. Because cardiac output was significantly higher in Blacks compared to Whites and Hispanics, additional comparisons of PWV and Zc were performed after adjustment for cardiac output and peripheral vascular resistance.
Results Compared with Whites, both Blacks and Hispanics had higher levels of aortic arch PWV (4.25, 95% confidence interval [CI]: 4.15 to 4.35 m/s, vs. 4.72, 95% CI: 4.64 to 4.81 m/s, vs. 4.48, 95% CI: 4.33 to 4.63 m/s, respectively, both p < 0.05 vs. White), and Zc (64.9, 95% CI: 63.3 to 66.6 dyne·s/cm5, vs. 75.6, 95% CI: 74.0 to 77.2 dyne·s/cm5, vs. 70.1, 95% CI: 67.6 to 72.8 dyne·s/cm5, respectively, both p < 0.01 vs. White) after adjustment for age, age squared, sex, body mass index, height, mean arterial blood pressure, antihypertensive treatment, heart rate, total cholesterol, diabetes mellitus, and smoking. Compared with Hispanics, Blacks also had higher level of both PWV and Zc (both p < 0.01). Ethnic differences in PWV and Zc persisted after adjustment for cardiac output and peripheral vascular resistance.
Conclusions In a multiethnic population-based-sample, Blacks and Hispanics had higher proximal aortic stiffness compared with Whites independent of blood pressure and relevant risk factors.
This study was supported by a grant from the Doris Duke Charitable Foundation to UT Southwestern to fund Research Fellow Akshay Goel. It was also supported by a grant UL1TR000451 from the National Center for Advancing Translational Sciences, National Institutes of Health, and UT Southwestern O’Brien Kidney Center grant P30 DK079328.
Dr. Mitchell is the owner of Cardiovascular Engineering, Inc., a company that develops and manufactures devices to measure vascular stiffness; serves as a consultant to and receives honoraria from Novartis, Merck, and Servier; and is funded by research grants HL094898, DK082447, HL107385, and HL104184 from the National Institutes of Health. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
Drs. King and Vongpatanasin are joint senior authors.
- Received March 16, 2016.
- Revision received July 25, 2016.
- Accepted July 28, 2016.
- American College of Cardiology Foundation