食道心エコー法が有用であった右室梗塞の1例

A case report of right ventricular infarction clearly detected by transesophageal echocardiography

　症例は70歳，女性。平成元年4月13日，午前8時10分頃急に胸痛を生じ全身痙攣を起こしたため緊急入院となった。入院時意識レベルIII−1〜2でショック状態であった。心電図ではII，III，aV_F，V₁〜V₃にST上昇を認め，心房細動に完全房室ブロックを伴っていたため一時ペーシングを施行した。入院時右心カテーテル所見は平均肺動脈模入圧12mmHg，肺動脈圧19／11mmHg，平均右房圧13mmHg，心係数1.33l／min／m²であった。容量負荷，カテコラミン，ニトロプルシッドの併用にて治療を行ったが，第4病日に肺動脈圧47／31mmHgへ急激に上昇したため挿管しPEEP 6 cmH₂Oをかけた。その後右室機能の良好な同復を認め，第7病日には抜管した。第5病日に食道心エコーを行い心基部側では右室後壁にdyskinesisを認め，心尖部側では全周性にakinesisの状態で，経胸壁アプローチでは観察困難であった右室壁運動異常の範囲および程度を詳細に評価できた。

We reported a case of a 70 year-old woman who suffered from right ventricular infarction with car-diogenic shock, detected clearly by transesophageal echocardiography.

On admission, her pulse rate was 31 bpm and her blood pressure was unobtainable. Conscious level was III-1~2 and she was cold and clamy. The ECG showed complete AV block with junctional escape rhythm at a rate of 31 bpm which required tem-porary pacing and ST elevation in leads II, III, aV_F, V_4R, V_3R, V₁. An echocardiogram showed akinesis of RV free wall and paradoxical septal motion. Transesophageal echocardiography was performed safely on the 5th hospital day and detected RV wall motion abnormality clearly. A Swan-Ganz catherter was inserted. Mean PCW was 12mmHg. PA pres-sure was 19/11mmHg. Mean RA pressure was 13mmHg. Cardiac index was 1.33 1/min/m². SvO² was 54%. Volume loading, administration of dopamine, dobutamine and nitroprusside were started. Cardiac index increased to 1.88l/min/m², and SvO² increased to 59%. On the 4th hospital day, mean RA pressure increased to 29 mmHg and PA pressure increased to 47/31mmHg acutely. Endotracheal intubation was done and PEEP 6cmH₂O was used and mean RA pressure and PA pressure decreased. On the 6th hospital day, cardiac index increased 4.08l/min/m². Cardiac catheterizationn done two months after acute myocardial infarction showed 75% stenosis of the proximal right coronary artery.