Validation of a new index for estimating arterial stiffness: measurement of the QPV interval by Doppler ultrasound.
BACKGROUND
Pulse wave velocity (PWV), a relevant indicator of arterial stiffness, can be measured noninvasively with a variety of automatic devices, but most are complexly equipped. We developed a novel index for estimating arterial stiffness as "QPV interval," which was determined by means of surface electrocardiogram and Doppler ultrasound of the brachial artery simultaneously.


OBJECTIVE
This study aimed to validate the QPV interval as an exact and convenient index for estimation of arterial stiffness.


METHODS
Forty-seven patients with untreated essential hypertension and 19 normotensive subjects were enrolled. Brachial-ankle PWV (baPWV) was measured using an automatic volume-plethysmographic apparatus, and Doppler ultrasound was implemented sequentially to measure the QPV interval in each subject. Clinical biochemistry and echocardiography were performed on the same day.


RESULTS
Mean baPWV was significantly higher in hypertensive patients than in normotensive subjects (p = 0.002), whereas mean QPV interval was significantly shorter in hypertensive patients than in the normotensive group (p = 0.019). A simple regression analysis demonstrated an inverse correlation between the QPV interval and baPWV (r = -0.671, p < 0.001) in all enrolled subjects. In a stepwise regression model that adjusted for age, systolic blood pressure, and other determinants of baPWV, the negative association remained between the QPV interval and baPWV (p < 0.001).


CONCLUSIONS
The QPV interval correlates inversely with baPWV, independent of age and other determinants of baPWV; hence, the QPV interval can serve as a simple and convenient index for assessing arterial stiffness in clinical practice.
Lee
Min-Yi
MY
Division of Cardiology, Department of Internal Medicine, Kaohsiung Municipal United Hospital, Taiwan.
Chu
Chih-Sheng
CS
Lee
Kun-Tai
KT
Wu
Chan-Ming
CM
Su
Ho-Min
HM
Lin
Shin-Jing
SJ
Sheu
Sheng-Hsiung
SH
Lai
Wen-Ter
WT
D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology*; D001916:Brachial Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D005260:Female; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011673:Pulsatile Flow / Q000502:physiology; D012044:Regression Analysis; D018608:Ultrasonography, Doppler