神田 章弘, 森内 正人, 谷川 直, 斉藤 穎, 鎌田 智彦, 小沢 友紀雄

Akihiro KANDA, Masahito MORIUCHI, Naoshi TANIGAWA, Satoshi SAITO, Tomohiko KAMATA, Yukio OZAWA

日本大学医学部第2内科

Nihon University School of Medicine, Second Department of Internal Medicine

キーワード : Transvenous Intracardiac Echocardiography, Endomyocardial biopsy, Catheter Ablation

Intracardiac catheter interventions such as catheter ablation and endomyocardial biopsy have been performed under fluoroscopic guidance; however, precise recognition of the catheter position is not possible. Transvenous intracardiac echocardiography (TVE) provides high-quality images of the heart and great vessels. We therefore assessed the usefulness of TVE as a guide during endomyocardial biopsy or catheter ablation experimentally. A 5 MHz transesophageal catheter (6.8 mm in diameter, Aloka Inc.) was introduced via the right femoral vein and positioned in the right atrium in 6 anesthetized dogs. A cardiac bioptome catheter or radiofrequency current electrode catheter (6Fr. large tip) was introduced via the left femoral vein or the left femoral artery and advanced into the right or left ventricle. An echo probe was hand-rotated to seek the bioptome catheter or ablation catheter. Endomyocardial biopsy (n=9) or catheter ablation (n=5) was then performed at various sites under echo guidance. Following these procedures, the heart was exercised, and biopsy and ablation sites were determined by macroscopic observation. The results showed that TVE could clearly demonstrate the inflow, outflow, free wall and septum of both ventricles, and successfully followed the course of the catheters in all dogs. Endomyocardial biopsy and catheter ablation sites were correctly identified in most cases (7/9=78% and 5/5=100%) when compared to those determined by macroscopic observation. Our preliminary data indicates that TVE may be useful as a guide during endomyocardial biopsy and catheter ablation, and may contribute to the improvement of the accuracy of these procedures.