Transpulmonary contrast-enhanced Doppler technique for the analysis ofpulmonary venous retrograde flow at atrial contraction

418

19th Meeting of the Japanese Society of Biorheolo~

MECHANICAL

Vol.

33, Nos. 4, 5

PROPERTIES OF DOG ARTERY

T. Takigawa, K. Nishimura, S. Katsuya, T Masuda, T. Nakamura*, and Y. Shimizu* Division of Material Chemistry and *Research Center for Biomedical engineering, Kyoto University, Kyoto, Japan Mechanical properties of carotid artery and abdominal aorta of adult dogs were investigated. The stress-straincurves in the logitudinal and circumferential directions, as well as pressure-volume curves were measured for the specimens. The stress-strain curves for both carotid artery and abdominal aorta in the longitudinal direction did not show hysteresis loops, and the shape sof the curves remained almost unchanged as the number of repeated stress-strain cycles increased. On the other hand, the hysteresis behavior was observed on the stress-strain curves for both specimens stretched in the circumferential direction. The hysteresisloop became smaller with increasing the number of repeating cycles. It was also found that the stress-strain curve of abdomial aorta in the longitudinal direction showed a rapid increase of stressaround extension ratio of 1.4.

Transpulmonary Contrast-Enhanced Pulmonary Venous Retrograde Flow

Doppler at Atria1

Technique Contraction

for

the

Analysis

of

K.Nariyama, M.Lee, T.Aoyama, H.Takahashi, T.Masuyama*, M.Hori* Department of Internal Medicine, Kaizuka Municipal Hospital, *The First Department of Internal Medicine, Osaka University School of Medicine, Kaizuka & Suita, JAPAN. Objectives: The aim of this study was to demonstrate the clinical usefulness of transpulmonary contrast enhanced Doppler technique in the analysis of the pulmonary venous retrograde flow at atria1 contraction (Apv) by comparing with transesophageal (TE) echocardiographic measurements. Background: Analysis of the peak flow velocity and/or duration of Apv is useful in the estimation of left ventricular diastolic pressure. However, poor signal-to-noise ratio often limits transthoracic (TT) study of this wave. Methods: Thirty-seven pts with various heart diseases were enrolled for the TE and TT echocardiographic study. Apv was sampled in the right upper pulmonary vein. The peak velocity and duration of Apv were determined in the TT recordings before and after intravenous injection of Albunex@ (2.5 ml) for comparison with TE measurements at the same location. Nine pts (24%) in whom TE Apv was very small or absent were excluded from this study, considering the limitation of TT resolution ability. Results: (1) In 11 pts (39%), Apv was not enhanced by peripheral venous contrast injection. (2) In the remaining 17 pts Apv was enhanced by contrast injection, Apv by control and enhanced TT study were compared with TE study. ADV TE vs control TT TE vs enhanced TT Peak velocity : y=.5x+12, r=.61, pc.01 y=.8x+4, r=.88, pc.01 Duration : NS v=.6x+58. r=.67. uc.01 Conclusions: The parameters of enhanced TT Apv showed a good correspondence to those of TE Apv. The transpulmonary contrast enhanced Doppler technique using Albunex@ enhances the value of transthoracic quantitative assessmentof Apv in pts.