Yoshio Yokota

Postoperative Size of the Right Ventricular Outflow Tract and Optimal Age in Complete Repair of Tetralogy of Fallot

Abstract One hundred forty-three patients underwent complete repair of tetralogy of Fallot with an overall mortality of 14.7%. The mortality rate correlated with the preoperative pulmonary artery to aorta (PA/Ao) diameter ratio but not with age. A retrospective study revealed that for success, the postoperative pulmonary annulus should be over 1.75 cm 2 per square meter of body surface area (BSA) in patients with a BSA of less than 0.6 m 2 at operation. The younger the patient, the lower was the ratio of right ventricular to aortic systolic pressure, even when the cross-sectional area index (CSAI) of the pulmonary annulus was the same. Even with application of an outflow patch, pulmonary regurgitation was negligible when the CSAI was less than 2.6 cm 2 /m 2 . The pulmonary vascular response to increased blood flow was excellent in younger patients. Residual ventricular septal defect and recurrent pulmonary stenosis were unrelated to age. Thus, for symptomatic patients, even infants, we recommend that complete repair be attempted when the PA/Ao diameter ratio is over 0.3. For patients in whom this ratio is less than 0.3, operation should be undertaken when the average diameter index of the arterial pathway to the right upper lobe is above 4 mm/m 2 . Should this index be less than 4 mm/m 2 , a two-stage operation is recommended.

Successful surgical repair of truncus arteriosus with interrupted aortic arch in infancy by an anterior approach

A 98-day-old infant was successfully operated on for truncus arteriosus (type I) with interrupted aortic arch (type B) using a one-stage anterior approach. The interrupted aortic arch was reconstructed by direct anastomosis between the ascending and descending aorta. The ventricular septal defect was closed, and a 12-mm porcine valved conduit was placed on the right side of the ascending aorta to establish continuity between the right ventricle and pulmonary artery. Surgical procedures for the repair of this malformation are the focus of discussion.

New modification of the Damus-Kaye-Stansel operation

We report a successful modification of the Damus-Kaye-Stansel operation for transposition of the great arteries when the coronary arteries are unsuitable for transfer. The procedure includes creation of a neoaorta with end-to-end anastomosis of the proximal pulmonary artery to the distal ascending aorta and creation of an aortopulmonary window between the proximal great arteries. A valved conduit is interposed between the right ventricle and the distal pulmonary artery.

Pulmonary stenosis after arterial switch operation for complete transposition of the great arteries(TGA).

近年,完全大血管転位症に対する動脈側スイッチ手術後,最も多くみられる合併症として肺動脈狭窄の発生が報告されている.われわれも12例の遠隔生存中4例に対し,進行性の肺動脈狭窄のため再手術を施行した.初回手術から再手術までの期間は平均2年6ヵ月であった.吻合部の狭小化または肺動脈絞扼部の発育不全による弁上狭窄を全例に認め,分岐部狭窄,弁狭窄を各1例に認めた.再手術は2例においてtransannular patchによる右室流出路再建,他の2例では主肺動脈,分岐部のパッチ拡大を行った.再手術による死亡はないが,再手術後も全例,軽度～中等度の圧較差が残存した.遠隔期の肺動脈狭窄は初回手術時の術式に起因する部分が大きいと思われ,最近では大血管の吻合を全周外面からのU字縫合とすること,冠動脈の移植に際しては,Valsalva洞の組織を可及的に温存したうえ,補綴には自己心膜を用いること,など術式の改良を試みている.