Non-invasive quantification of aortic regurgitation by Doppler echocardiography.

Abstract

SUMMARY This study was undertaken to assess the contribution of Doppler echocardiography to the quantification of aortic valve regurgitation. Ultrasound examination was performed by recording aortic arch blood flow from the suprasternal notch. A non-invasive index of valve regurgitation was obtained by calculating the ratio between the maximal amplitude of forward flow during systole and the amplitude of retrograde flow during diastole measured at the onset of the R wave of the electrocardiogram. This index was compared with semiquantitative data derived from supravalvular aortography in 93 patients. In pure aortic regurgitation (67 patients) the results showed a high correlation coefficient between Doppler and angiographic estimates. In cases of associated aortic valve stenosis there were problems in the accurate estimation of systolic blood flow which led to global overestimation in general of the degree of regurgitation and considerable lack of precision in individual patients. But in general Doppler echocardiography appeared to be a successful technique to quantify pure aortic regurgitation. tion,5 6 ventricular septal defect,7 8 atrial septal defect,9 pulmonary hypertension and persistent ductus arteriosus,10 aortic stenosis," and aortic regurgitation. 2-14The present study compares the degree of aortic regurgitation estimated by supravalvular aortography with quantitative measurements derived from Doppler echocardiography. Subjects and methods PRINCIPLESDoppler echocardiography has been adapted to the study of blood flow from techniques developed in radar systems.2-4 Curves are obtained by comparing the frequencies of emitted and back scattered ultrasound. These curves are related to the velocity of red cells by a factor that depends in particular on the angle between the ultrasound beam and the axis along which the target cells are moving. Pulsed emission provides echocardiographic data and allows selection of the depth and thickness of the sample volume.

Assessment of the severity of aortic regurgitation with pulsed wave Doppler velocity profile in the descending aorta

“…According to Pearson correlation analysis their correlation was very significant (r=0.69, p<0.001). Previous studies showed that forward and reverse flow profiles in the ascending aorta can be irregular and unreliable (12,13). However, there are other studies showing that descending aorta velocity profile was more reliable (14,15).…”

“…Previous studies have reported a good correlation between severity of aortic regurgitation and Doppler assessment of flow velocity at the end of diastole in the descending aorta just beneath the aortic isthmus (11)(12)(13)(14). Also descending aorta velocity profile was more reliable than ascending aorta (15).…”

“…Furthermore, movement during cardiac cycle is much less in the aortic isthmus than the ascending aorta, allowing better positioning of the sample volume (15). The measurements in early diastole were affected by the aortic wall compliance, so they were not used in identification (13).…”

Multigate Quality Doppler Profiles Technology in Vascular, Obstetrics and Cardiology Applications

“…In Adult Cardiology, QDP was used for the evaluation of the retrograde diastolic flow in aortic arch as an indirect method for the evaluation of the severity of aortic insufficiency [3]. The QDP was of help regarding the PW SVP for the reflux evaluation and analysis of the turbulent flow.…”

“…In the present work, this technology was tested in vitro as well as in different clinical applications and in different vessels, with a variety of transducer typologies. The considered clinical studies were: Vascular, regarding both arteries and veins at the neck district level (Common Carotid Artery -CCA, Internal Jugular Vein -IJV and Vertebral Vein VV) [1] Cardiology, regarding both Adult and Pediatric (Aorta and Inferior Vena Cava -IVC) [2][3] Obstetrics, about the study of uterine arteries in pregnancy [4][5] In all cases, QDP was used together with classic Doppler technologies such as PW and Color Doppler (CD), as well as a stand-alone Doppler tool. Longitudinal scanning of the examined vessels was considered with linear and convex transducers.…”