瀧聞 浄宏

Kiyohiro TAKIGIKU

長野県立こども病院循環器科

Nagano Children's Hospital, Department of Pediatric Cardiology

キーワード : congenital heart disease, real-time three-dimensional echocardiography, transpericardial real-time three-dimensional echocardiography, spatiotemporal image correlation

実臨床の場において，先天性心疾患に対し，リアルタイム3次元心エコーをどのように使うか．最も有効な活用方法の1つは，複雑な心内形態を3次元表示し，それに基づいて修復術のプランニングとガイドを行うことである．例えば，両大血管右室起始症における心室中隔欠損を用いた心内ルート作成，複雑な房室弁閉鎖不全の形成，心内狭窄病変の解除などである．また，カテーテル治療の適応判断や治療中のモニタリングにも有効である（日本ではまだ心房中隔欠損の経皮的閉鎖だが，欧米では心室中隔欠損にも使用されている）．さらに，経食道の使用できない小児において，心内表示の最も優れたアプローチ法は経心膜であり，直接3次元探触子を当ててvolume dataを収集することでSN比，解像度ともに良質な画像を得ることができる．Surgen’s veiwで内科医と外科医が共通の視点から，手術場で対話することができ，利用価値は高い．近年，胎児心臓超音波検査でも心臓の動きから同期をかけて3次元を再構築し，心臓病のスクリーニングをするというspatiotemporal image correlation（STIC）といわれる心エコー法も臨床応用されてきている．今後は，心機能や弁機能に関する3次元解析が先天性心疾患の分野でも進み，定量評価の結果が疾患のモービリティーやモータリティーの予測および改善に貢献していくことが望まれる．

How can we utilize real-time three-dimensional (3D) echocardiography for diagnosis and treatment of congenital heart diseases? One of the most effective applications is to obtain critical information on complicated intracardiac 3D structures of the heart for planning of cardiac surgery, such as creation of an intracardiac route via a ventricular septal defect in patients with double outlet right ventricle, valvuloplasty for complicated atrioventricular valve regurgitation, or repair of intracardiac stenotic lesions. It is also useful for determining whether catheter intervention is indicated and for monitoring the procedure (while 3D echocardiography is only used for percutaneous atrial septal defect closure in Japan, it is also used for percutaneous ventricular septal defect closure in the US and Europe). Furthermore, transpericardial real-time 3D echocardiography is performed by placing the ultrasound probe directly onto the pericardium enables us to collect volume data with a high SN ratio and image resolution in pediatric patients for whom transesophageal echocardiography cannot be applied. This approach also enables both cardiovascular surgeons and cardiologists to share the ‘surgeon's view’ in the operating room. A new type to fetal echocardiography using the spatiotemporal image correlation (STIC) technique, which can reconstruct 3D fetal heart images by triggering the fetal cardiac motion, has been applied to fetal heart disease screening. Further investigations of 3D cardiac and valvular functions in congenital heart diseases are necessary to predict and improve the morbidity and the mortality of congenital heart diseases.