DETERMINATION OF AORTIC PULSE WAVE VELOCITY USING THE METHOD OF ULTRASOUND DUPLEX SCANNING
Aim: the development of the measurement of the regional aortic stiffness protocol (pulse wave velocity (PWVus)) using ultrasound duplex scanning and the due age values of PWV for identifying the patients with a higher aortic stiffness. Sabjects and methods: the study is included 200 subjects: 75 healthy volunteers, 125 patients with cardiac profile, including: 17 patients with coronary heart disease, 68 patients with arterial hypertension, 40 patients with combined coronary artery disease and hypertension. All the patients got the aortic PWV measurement by the ultrasound duplex scanning and carotid-femoral pulse wave velocity (cfPWV) measurement by the sphygmographic method. The detailed methodology of the research is presented in the article. Results: the feasibility of the method of ultrasound duplex scanning was 95%. The variation coefficient was equal to 7.6% in the study of intra-operator reproducibility and 9.3% in the study of inter-operator reproducibility. According to the data of ultrasonic method PWVus 6.5 (5,2;7,8) m/s; and was significantly lower than cfPWV according to classical methods, which was 8.0 (6,6;9,4) m/s, p<0,05. However, there was a close correlation between the two values of PWV, r=0.85, p< 0,0001. The strong dependence between PWVus and age was showed. The correlation coefficient was r=0,66 (p=0.0001). Due values for PWVus were developed above which it is concluded that «increased stiffness» of the aorta: in subjects under 30 years - 5.9 m/s, 30-39 years - 6.6 m/s, 40-49 years - 7.0 m/s, 50-59 years - 8,0m/s, 60-69 years - 10.3 m/s, with over 70 years of age 11,4m/s. PWVus more than 8 m/s was recommended as the universal criterion of the increased aortic stiffness. Sensitivity 83% and specificity 89% were obtained when the diagnostic accuracy estimate of PWVus took place. The degree of coincidence with the results of diagnostics of high aortic stiffness by sphygmographic method amounted 0.75±0,086; 95% CI = 0,58-0,92, indicating a high consistency of results between the two methods. Conclusion: the technique of the aortic pulse wave velocity measuring by ultrasound duplex scanning is presented. The method is characterized by the high feasibility, reproducibility, accuracy. The PWVus values correlates with cfPWV values measured with the using of the methods recommended in the clinical practice. Due age values of PWVus in the aorta, obtained using the proposed Protocol of ultrasound research are developed.