Hiroaki Aida

Long-term results of primary closure for ventricular septal defects in the first year of life

The long-term results of primary closure for large ventricular septal defects (VSDs) in infants under 1 year of age with severe symptoms were studied over a period of more than 10 years. Between January, 1971 and March, 1982, 49 infants underwent primary closure of a VSD through a right ventriculotomy using complete cardiopulmonary bypass with mild hypothermia. There were four hospital deaths but no late deaths. Two of four infants with residual shunts had a left ventricular-right atrial shunt which necessitated reoperation. Surgical heart. block occurred in two infants who recovered sinus rhythm in the late period. The cardiothoracic ratio decreased from 60.5% preoperatively to 50.6% in the late postoperative period. Examination by cardiac catheterization revealed that the pulmonary-to-systemic pressure ratio (Pp/Ps) of 23 patients with a Pp/Ps of over 0.75 fell from 0.89 ± 0.09 preoperatively to 0.42 ± 0.12 by 1 month postoperatively, then to 0.27 ± 0.05 in the late postoperative period. The latest values for the cardiac index and left ventricular ejection fraction were 3.41 /min per m2 and 64.4%, respectively. More than 10 years after their operation, all the survivors were growing normally and maintaining a good quality of life, which supports our recommendation that primary repair should be performed in the first year of life for infants with large VSDs.

Composite graft replacement of the aortic root in patients with Marfan's syndrome

Between October, 1979 and September 1994, 18 consecutive patients with Marfans syndrome underwent replacement of the ascending aorta and aortic valve with a composite graft. There were 11 men and seven women; the mean age was 38.7 years. All patients had annuloaortic ectasia with significant aortic regurgitation. Ten of the 18 patients had aortic dissection. Concomitant procedures were performed in three patients. The hospital mortality rate was 17%, and two patients with concomitant procedures died early after surgery. There were three late deaths, two of which were related to late aortic complications. The actuarial 8-year survival rates in patients with and without aortic dissection were 58.3% and 77.8%, respectively. Since aortic dilatation and its complications are progressive in patients with Marfans syndrome, improved surgical results can be obtained early in the course of the disease before cardiac disturbances and aortic dissections emerge.

Surgical Treatment of Double Aortic Arch and Associated Problems of Tracheomalacia, and Intracardiac Anomalies.

乳幼児期に呼吸器症状にて発症した重複大動脈弓3症例に対し, 大動脈弓離断術を施行した. 2例が気管軟化症を, 全例に心内奇形を合併していた. これが原因で3例ともに術後の長期呼吸管理を要した. 1例は残存するVSD+PHによる心不全, 呼吸不全のために第49病日にVSD閉鎖を必要とした. われわれの経験した気管軟化症合併例はいずれも保存的治療にて抜管可能であった. 気管軟化症に対する外科治療としては Aortopexy, Splinting, ステントなどが試みられているが, 決定的な術式はないのが現実であり, われわれは積極的に同時手術を行ってはいない. しかし, 血管輪解除術後にも呼吸器症状が改善しない症例では症状の主たる原因が何に起因するのかを見極め, 適切な治療方針をたてる必要がある.

Surgical Treatment of Acute Aortic Dissection: Efficacy of Retrograde Cardioplegia for Myocardial Protection

The operative morbidity and mortality of patients with Stanford type A acute aortic dissection undergoing urgent operation using retrograde cadioplegia for myocardial protection were evaluated to assess the efficacy of such surgery. A total of 18 patients (12 men and six women. 19–71 years of age) were operated on 9–137 h after onset of dissection using cardiopulmonary bypass with deep hypothermia and retrograde cardioplegia. Graft replacement was performed in ten patients, primary anastomosis in three, and Cabrol and Bentall operations in five. All patients were weaned from cardiopulmonary bypass, but four died in hospital (mortality rate 22%). Thirteen patients were in good health at follow-up ranging from 3 to 98 months, and the remaining patient died from rectal cancer 5 months after surgery. It is concluded that urgent operation of patients with Stanford type A acute aortic dissection can be performed with reasonable operative and excellent follow-up results. Retrograde cardioplegia is an easy and reliable method of myocardial protection to repair the fragile aortic wall.

Coronary artery bypass grafting in patients with depressed left ventricular function: Operative results and long-term follow-up

Nine consecutive patients with coronary artery disease who had a left ventricular ejection fraction (LVEF) of less than 0.4 and underwent coronary artery bypass grafting (CABG) at our institution were studied. All patients had angina pectoris and six of the nine patients (67%) had a history of congestive heart failure. The mean EF was 0.37±0.03 and the mean LV end-diastolic pressure was 10.1±4.9 mm Hg. An average of 1.56±0.50 grafts per patient were placed and there was no operative death. The graft patency rate was 92.9% and the mean EF rose significantly from 0.37 to 0.53 after surgery (P<0.05). There was one late death, the 4-year actuarial survival rate being 88.9%. Of the eight long-term survivors, six (75%) were totally asymptomatic and only two had mild angina on exertion. This study confirmed that CABG for patients with depressed LV dysfunction can be performed safely with an acceptably low operative mortality, a significant improvement of LV function, and excellent long-term results.

Clinical Study on Peripheral and Visceral Aneurysms.

1975年から1990年までに外科治療を行った四肢および腹部臓器の末梢動脈瘤症例は34例であった. 動脈瘤の発生部位は, ほぼ全身にわたっていたが, 下肢が最も多かった. その成因としては動脈硬化が半数以上を占め, 次いで医原性が24%のほか, 外傷, Behcet 病, aortitis などがあった. 動脈硬化性のものは左右両側に発生する多発例が多かった. 全体の破裂の頻度が26%と高率であるのと, 体表から深い位置にある腹部臓器動脈瘤や内腸骨動脈瘤などが激しい突発症状で発症するのが診断上の問題であった. 末梢動脈瘤の手術成績は良好であるが, 遠隔期に心血管系の続発症が多いので, 術後も注意深い経過観察が必要である.