林 真見子, 大木 崇, 井内 新, 内田 知行, 河野 智彦, 小川 聡, 影治 好美, 恵美 滋文, 細井 憲三, 福田 信夫, 森 博愛

Mamiko HAYASHI, Takashi OKI, Arata IUCHI, Tomoyuki UCHIDA, Tomohiko KAWANO, Satoru OGAWA, Yoshimi KAGEJI, Shigefumi EMI, Kenzo HOSOI, Nobuo FUKUDA, Hiroyoshi MORI

徳島大学医学部第2内科

The Second Department of Internal Medicine, School of Medicine, University of Tokushima

キーワード : Atrial septal defect, Shunt flow, Transesophageal echocardiography

Transesophageal pulsed (TEE-PD) and color Doppler (TEE-CD) echocardiography were performed to evaluate the shunt and right atrial flow patterns in 22 patients with atrial septal defect (ASD) of secundum type, 4 with endocardial cushion defect (ECD) of incomplete type, 4 with patent foramen ovale (PFO) and 30 normal subjects. Various results obtained by TEE were compared with those from cardiac catheterization.
1) In ASD and ECD, the basic contour of left to right (L-R) shunt flow signal by TEE-PD was characterized by a triphasic pattern: mid- to end-systolic (S), early to mid-diastolic (D) and atrial contraction (AC) waves. With the elevation of pulmonary artery pressure, the shunt flow showed a "spiky" pattern due to the shortening of time duration of each wave. In PFO, the shunt flow tended to be a monophasic or dome shaped pattern by fusion of S, D and AC waves.
2) The total L-R shunt flow integral (TSI) of ASD correlated well with systolic pulmonary artery pressure (r=-0.60, p3) Ratio of the peak velocity of the S wave to the AC wave (S/AC) correlated well with age (r=-0.77, p4) Defect area correlated well with right ventricular demension (r=0.55, p5) TEE-CD indicated not only the L-R but also the right to left (R-L) shunt flow signal across the defect in detail. In particular, R-L shunt flow was frequently detected at early phase of atrial contraction period, and appearance of the shunt flow signal was easily influenced by a) tricuspid regurgitation, b) time lag between left and right atrial contraction and c) right atrial flow from vena cava, at the state of severe pulmonary hypertension.
These results suggest that the TEE-PD and -CD are useful for the observations of the shunt and right atrial flow in ASD and ECD, and that information on the shunt flow signal could be used to evaluate the severity of the defect abnormalities.