An ultrasonic sound wave equipment will be used (Acuson, Model 128XP System, Mountain View, California, USA), with vascular software for two-dimensional images (2D), color Doppler with an internal electrocardiogram (ECG) monitor and a high-frequency vascular transducer (Acuson, Model L7 7,5-10 MHz, Mountain View, California, USA). After positioned, a segment with anterior and posterior interfaces with the arterial wall will be selected for 2D images. Arterial diameter values will be recorded in super-VHS for subsequent analysis.