Ultrasonic bicycle exercises diagnostics of early cerebrovascular dysfunction at patients with an arterial hypertension

Abstract

Purpose. To estimate early decrease of cerebrovascular function in the course of ultrasonic bicycle exercise dynamic change of peak velocity and resistant index of brain blood circulation at patients with an arterial hypertension.Methods: The group of patients with an arterial hypertension of the I–II degree (No. 1, n=23) and group of conditionally healthy faces (No. 2, n=27) comparable age is examined 53 [47–58] years. In the course of the Doppler research of the middle brain artery the peak velocity (Vps) and resistant index (RI) in a supine position was registered, sitting also during bicycle exercise.Results: In a supine position of Vps was equal 79 [77–82] cm/s and 82 [79,5–85] cm/s, respectively, RI was identical — 0,62 [0,58–0,64]. In a sitting position on the stationary bicycle Vps decreased in the main group by 13,5% [11,2–15,5], and in group of control — for 5% [3,8–7,2]. In the course of bicycle exercise of average intensity, which corresponded to 70% of threshold power, growth of Vps at patients with AG was 30% [27,4–32,6] of reference orthostatic values, and in group of control — 44% [38–48,2] (p<0,0001). Similarly also peripheral vascular resistance increased, RI increased by 15,8% [13,9–20,8] and for 18,8% [15–22,6], respectively. At peak of bicycle exercise reduction of Vps in the main group for 15% [7,2–10] of the maximum values, and in group of control — for 11% [8,4–12,2] was observed, at this RI significantly did not change. Conclusion. Adequate increase peak velocity in an middle brain artery not less than 30% in the course of exercises, unproductive increase peak velocity at patients with an arterial hypertension of the I–II degree indicates decrease in vasomotor cerebrovascular function> <0,0001). Similarly also peripheral vascular resistance increased, RI increased by 15,8% [13,9–20,8] and for 18,8% [15–22,6], respectively. At peak of bicycle exercise reduction of Vps in the main group for 15% [7,2–10] of the maximum values, and in group of control — for 11% [8,4–12,2] was observed, at this RI significantly did not change.Conclusion. Adequate increase peak velocity in an middle brain artery not less than 30% in the course of exercises, unproductive increase peak velocity at patients with an arterial hypertension of the I–II degree indicates decrease in vasomotor cerebrovascular function.