Left Ventricular Function Assessed by One-Point Carotid Wave Intensity in Newly Diagnosed Untreated Hypertensive Patients
To investigate whether newly diagnosed untreated hypertensive patients show higher left ventricular (LV) contractility, as assessed by traditional echocardiographic indices and carotid wave intensity (WI) parameters, including amplitude of the peak during early (W1) and late systole (W2).
A total of 145 untreated hypertensive patients were compared with 145 age- and sex-matched normotensive subjects. They underwent comprehensive echocardiography and WI analysis. WI analysis was performed at the level of the common carotid artery. The diameter changes were the difference between the displacement of the anterior and posterior walls, with the cursors set to track the media-adventitia boundaries 2 cm proximal to the carotid bulb and calibrated by systolic and diastolic BP. Peak acceleration was derived from blood flow velocity measured by Doppler sonography with the range-gate positioned at the center of the vessel diameter. WI was based on the calculation of (dP/dt)×(dU/dt), where dP/dt and dU/dt were the derivatives of BP (P) and velocity (U) with respect to time. One-point pulse wave velocity (PWVβ) and the interval between the R wave on ECG and the first peak of WI (R-W1), using a high definition echo-tracking system implemented in the ultrasound machine (Aloka), were also derived.
After adjustment for body weight, heart rate, and physical activity, the two groups had similar general characteristics and diastolic function. However, hypertensives showed significantly higher LV mass, LV ejection fraction (LVEF), circumferential and LV end-systolic stress, and one-point PWV as well as W1 (13.646 ± 7.368 vs 9.308 ± 4.675 mmHg m/s3, P =.001) and W2 (4.289 ± 2.017 vs 2.995 ± 1.868 mmHg m/s3, P =.001). Hypertensives were divided into tertiles according to LVEF: W1 (11.934 ± 5.836 vs 11.576 ± 5.857 vs 17.227 ± 8.889 mmHg m/s3, P <.0001) was higher in the highest LVEF tertile along with relative wall thickness, midwall fractional shortening, endocardial fractional shortening, and R-W1.
Newly diagnosed hypertensives show increased LVM and LV contractility, including carotid WI parameters and R-W1 values, as compared with normotensive subjects, but no differences in LV diastolic function.