超音波検査技術

ISSN: 1881-4506
一般社団法人日本超音波検査学会
〒162-0801 東京都新宿区山吹町358-5
Japanese Journal of Medical Ultrasound Technology 43(4): 440-449 (2018)
doi:10.11272/jss.43.440

原著Original Article

右室流出路波形を用いた肺高血圧評価における描出断面による影響Analysis of the Influence by Visualized Direction on the Right Ventricular Outflow Doppler Waveform in Patients with Pulmonary Hypertension

1鹿児島大学病院臨床技術部検査部門Division of Clinical Laboratory, Kagoshima University Hospital

2鹿児島大学大学院医歯学総合研究科心臓血管・高血圧内科学Department of Cardiovasucular Medicine and Hypertension, Graduate School of Medical and Dental Sciences, Kagoshima University

3鹿児島大学医学部保健学科Faculty of Medicine School of Health Sciences, Kagoshima University

受付日:2018年1月10日Received: January 10, 2018
受理日:2018年4月13日Accepted: April 13, 2018
発行日:2018年8月1日Published: August 1, 2018
HTMLPDFEPUB3

目的:心エコー法による肺高血圧の評価では,肺動脈圧上昇に伴い,右室流出路血流速波形(RVOF)は2相性波形を呈し,加速時間の短縮がみられるようになる.また,RVOFのパターンの違いが,肺血管抵抗(PVR)の上昇と相関があるとの報告もあり,RVOFを解析することは,肺高血圧の評価において重要であると考えらえる.しかし,実際の症例では,RVOFのパターンが描出方向で一致しないこともあり,2相性の有無の判断や計測に迷う例も多い.そこで,今回,我々は,RVOFの描出断面による波形の違いと,肺高血圧評価に対する影響について検討を行った.

対象と方法:対象は,肺高血圧疑いで心エコーを施行した連続69例(男性12例,女性57例),平均年齢59±15歳.同一症例において,RVOFを大動脈弁短軸断面,右室流出路長軸断面,心窩部断面の3方向からパルスドプラ法にて記録した.右心カテーテル検査を施行した40例に関しては,PVRとRVOFの比較を行った.

結果と考察: 3方向から記録したRVOFは,心窩部断面で有意に記録不可例が多く(p<0.01),2相性波の検出率も低値であった(p<0.05).また,大動脈弁短軸断面,右室流出路長軸断面では2相性波を認めた群では,2相性波を認めなかった群に対し有意にPVRが高値を示したが(p<0.05),心窩部断面では2相性波の有無でPVR値に有意差は認めず,心窩部断面では,2相性波の有無で,PVR上昇を推定することは困難であると考えられた.一方,RVOFの時間速度積分値(VTI)は3方向いずれの断面でも,PVRとの相関がみられ(大動脈弁短軸断面r=-0.47, 右室流出路長軸断面r=-0.52,心窩部断面r=-0.56),流量を反映するVTIはPVRの推定に有用であると考えられた.

結論:心窩部断面からのアプローチでは,流量を反映するVTIは,PVRと良好な相関を示したが,PVR上昇を反映する2相性波パターンの検出には限界があり,注意が必要であると考えられた.

Background: In evaluating pulmonary hypertension by echocardiography, the biphasic waveform and shortening of acceleration time of the right ventricular outflow tract Doppler flow (RVOF) are frequently seen in accordance with increasing of pulmonary artery pressure. In addition, it has been reported that the biphasic waveform of RVOF relates to the highly elevated pulmonary vascular resistance (PVR). Therefore, it is important to analyze the RVOF waveform in evaluation of pulmonary hypertension. However, the RVOF waveform often varies, depending on the visualized direction. The purpose of this study was to analyze the influence by the visualized direction on the RVOF Doppler waveform in patients with pulmonary hypertension.

Subjects and Methods: Sixty-nine consecutive patients (12 males, 57 females, average age 59±15 years) who underwent echocardiographic examination for evaluation of pulmonary hypertension were in the study. RVOF was acquired by the pulsed wave Doppler method from three directions: the aortic valve short-axis view, the right ventricular outflow tract view, and the epigastrium view. In 40 patients who underwent right heart catheterization (RHC), the RVOF was compared with the PVR calculated by the RHC.

Results and Discussion: Impossible evaluation rate of RVOF and was significantly high for the epigastric view (p<0.01). The detection rate of the biphasic waveform reflecting the increasing PVR was significantly low for the epigastric view (p<0.05). In patients with the biphasic waveform of the RVOF from all directions except the epigastric view, PVR significantly increased compared to the patients without the biphasic waveform of the RVOF (p<0.05). Therefore, it was difficult to estimate the increasing of PVR by the RVOF from the epigastric view. On the other hand, the velocity time integral (VTI) of the RVOF reflecting the flow volume from all three directions correlated with the PVR calculated by the RHC (aortic valve short-axis view r=-0.47, right ventricular outflow tract view r=-0.52, epigastric view r=-0.56). Therefore, independent of the visualized direction, the VTI of the RVOF was considered to be useful for an index to reflect PVR.

Conclusion: In RVOF from the epigastric view, the VTI reflecting the flow volume was shown to have a good correlation with the PVR, but there was a limitation to detect the biphasic waveform reflecting the increasing PVR.

Key words: pulmonary hypertention; right ventricular outflow tract Doppler flow; biphasic wave form; pulmonary vascular resistance

This page was created on 2018-06-13T11:07:53.185+09:00
This page was last modified on 2018-08-01T15:16:24.930+09:00


このサイトは(株)国際文献社によって運用されています。