High central blood pressure, augmentation index and pulse wave velocity are independent cardiovascular risk factors. Little is known of the effect of baroreflex activation therapy on central hemodynamics.
In this prospective clinical trial, radial artery applanation tonometry and pulse wave analysis were used to derive central aortic pressure and hemodynamic indices (i.e. augmentation pressure, augmentation index, pulse wave velocity, systolic and diastolic pressure time integral, subendocardial viability index) at baseline and 6 months after starting baroreflex activation therapy in 25 patients with resistant hypertension.
Apart from peripheral blood pressure reduction, 6 months of baroreflex activation therapy significantly reduced mean central aortic blood pressure from 109.7 ± 20.5 to 97.4 ± 18.8 mmHg (P < 0.01) and aortic pulse pressure from 62.9 ± 18.6 to 55.2 ± 16.0 mmHg (P < 0.01). Aortic augmentation pressure and augmentation index at a heart rate of 75 b.p.m. were significantly reduced by 4.3 ± 7.9 mmHg (P = 0.01) and 3.5 ± 6.8% (P = 0.02). Additionally, pulse wave velocity decreased from 10.3 ± 2.6 to 8.6 ± 1.3 m/s (P < 0.01) 6 months after starting baroreflex activation therapy. Systolic pressure time integral was significantly reduced (P = 0.03), whereas subendocardial viability index remained unchanged.
Apart from peripheral blood pressure, baroreflex activation therapy reduces central blood pressure, augmentation index at a heart rate of 75 b.p.m. and pulse wave velocity in patients with resistant hypertension, suggesting strong potential to reduce cardiovascular risk.
aDepartment of Nephrology and Rheumatology
bDepartment of Cardiology and Pneumology
cDepartment of Medical Statistics, University of Göttingen
dSt Josefs Hospital, Cloppenburg, Germany
Correspondence to Michael J. Koziolek, MD, Department of Nephrology and Rheumatology, Georg-August-University Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen, Germany. Tel: +49 551 39 6331; fax: +49 551 39 8906; e-mail: email@example.com
Abbreviations: ABPM, ambulatory blood pressure monitoring; AIx, augmentation index; AIx@75, augmentation index at a heart rate of 75 b.p.m.; BAT, baroreflex activation therapy; BP, blood pressure; CKD, chronic kidney disease; DPTI, diastolic pressure time integral; MBP, mean arterial blood pressure; PP, pulse pressure; PWA, pulse wave analysis; PWV, pulse wave velocity; PWVcf, carotid-to-femoral pulse wave velocity; SEVR, subendocardial viability ratio; SPTI, systolic pressure time integral
Received 9 April, 2014
Revised 25 July, 2014
Accepted 25 July, 2014