新しい経カテーテル治療と麻酔

Structural Heart Disease Interventions and Anesthesia

はじめに

　大動脈弁狭窄に対する経カテーテル大動脈弁留置術（transcatheter aortic valve implantation：TAVI）の成功を受けて，構造的心疾患（structural heart disease：SHD）のカテーテル治療は近年急速な発展を遂げている。これらの治療は開胸や体外循環・心停止を必要としないため低侵襲で行うことができるが，別の言い方をすれば外科手術のリスクが高い患者が治療対象になる，ということでもある。安全な麻酔管理のためには患者の病態を正しく把握することはもちろん，手技内容を理解し合併症に備えることが必要である。

　本論文では新しいカテーテル治療として，広がりつつある経皮的僧帽弁接合不全修復術（transcatheter mitral edge-to-edge repair：M-TEER），今後の導入が期待されている三尖弁に対するカテーテル治療，そして心房細動患者に脳塞栓予防のため行われている経皮的左心耳閉鎖（percutaneous left atrial appendage occlusion：LAAO）について解説する。

　The applications of transcatheter therapies for structural heart disease are growing rapidly. Although these therapies are minimally invasive, the appropriate patients are typically frail, older, and have coexisting conditions；careful perioperative management is therefore essential.

　Patients with mitral regurgitation（MR）or tricuspid regurgitation（TR）have various degrees of pulmonary hypertension（PH）and right ventricular（RV）dysfunction.

　There is a risk that changes in patients’ respiratory patterns due to general anesthesia may increase the RV afterload and decrease cardiac output. It is thus necessary to determine the status of each patient’s RV function and PH, as well as left ventricular（LV）function, during preoperative testing such as echocardiography or right-heart catheterization.

　In Japan, transcatheter mitral edge-to-edge repair（M-TEER）is currently in clinical use for MR. For TR, transcatheter edge-to-edge repair（T-TEER）and transcatheter tricuspid valve replacement（TTVR）are expected to be introduced in Japan in the future.

　Cerebral embolization, a serious potential complication for patients with atrial fibrillation, are caused by thrombus that form in the left atrial appendage. Anticoagulation drugs are indicated for such patients, but percutaneous left atrial appendage occlusion is performed when the risk of bleeding complication is high.

　With the advent of these new treatments, we anesthesiologist are required to manage high-risk patients.