Aortic Arch Replacement for Arch Aneurysm with a Porcelain Aorta Using Transapical Aortic Cannulation / 日本心臓血管外科学会雑誌

Porcelain aorta entails a high risk of cerebral as well as systemic embolism. We describe a case of aortic arch aneurysm with a circumferentially calcified aorta. The patient was a 61-year-old man on chronic hemodialysis who received aortic arch replacement. However, since chest CT scan revealed a totally calcified porcelain aorta and heavily calcified axillary artery, axillary artery cannulation was deemed to be contraindicated. On the other hand, possible complications caused by femoral artery cannulation are also well known, such as cerebral embolization. Therefore, transapical aortic cannula was used and aortic arch replacement was performed under deep hypothermic circulatory arrest. The patient was weaned from cardiopulmonary bypass without difficulty and had an uneventful recovery without any neurologic complications.

Lower Mini-Sternotomy for Direct Coronary Artery Bypass on the Beating Heart / 日本心臓血管外科学会雑誌

Although left anterior descending coronary artery (LAD) grafting with a left internal thoracic artery (ITA) on a beating heart via a small left anterior thoracotomy (LAST) has become widely accepted, significant limitations exist due to the limited surgeon experience, smallness of exposure, thus making harvesting of the ITA, visualization of the surgical field and anastomosis quite difficult. Patients often have significant pain and wound complications postoperatively. A lower mini-sternotomy approach in 4 patients was performed from December 1998 through January 1999. Results: The length of mini-sternotomy incision is 7 to 14cm. These operations were accomplished without morbidity or mortality. No patients required intraoperative conversion to conventional bypass. Postoperative angiography showed patency of graft without stenosis of the anastomosis in all 4 patients. The patients did not complain of significant pain and their postoperative hospital stay was 5 to 11 days. The lower mini-sternotomy approach or“xyphoid” approach proposed by Benetti seems to be an excellent novel approach giving the freedom of extension of the incision if needed with satisfactory exposure for left ITA harvest and access to LAD as well as the distal RCA, and causes less postoperative incisional pain.

Operative and Late Results of Conventional CABG / 日本心臓血管外科学会雑誌

This study reviewed the operative results in patients who underwent elective isolated coronary artery bypass grafting (CABG) from 1991 to 1997 and the long-term outcome in patients who received an internal thoracic artery (ITA) to left anterior descending artery graft from 1984 to 1995. The morbidity rates were as follows: low output syndrome (LOS), 19 (2.6%); perioperative myocardial infarction (PMI), 14 (1.9%); IABP required, 9 (1.2%); respiratory insufficiency, 32 (4.4%); acute renal failure, 28 (3.8%); mediastinitis, 9 (1.2%); stroke, 13 (1.8%); and reoperation for bleeding, 9 (1.2%). Operative mortality was 0.7%. Patients with moderate or severe impairment of left ventricular function (ejection fraction≤40) or chronic renal failure had high incidences of arrthythmia and respiratory insufficiency; those who were 75 or older at operation had a higher incidence of arrhythmia than those who were 50 or under (<i>p</i>=0.033). Patients who received four or five grafts needed a longer duration of hospitalization than those who received a single graft (<i>p</i>=0.0147). The 10-year actuarial survival rate, cardiac death-free rate and cardiac event-free rate in the entire series were 89.4%, 96.7%, and 80.9%, respectively. Among patients who underwent complete revascularization, the 10-year cardiac event-free rate and catheter intervention-free rate were 82.7% and 91.7%, respectively, compared with 77.5% and 84.2% in patients who underwent incomplete revascularization (<i>p</i>=0.0428, 0.0343). Since this study demonstrated that CABG with cardiopulmonary bypass contributed to favorable operative and long-term results, the indications for minimally invasive direct coronary artery bypass (MIDCAB) and off-pump CABG should be considered carefully and perhaps limited to elderly patients and/or those with major co-morbidities, until the long-term benefits have been clarified.

A Multicenter Trial of Anticoagulant Therapy after Cardiac Valve Replacement / 日本心臓血管外科学会雑誌

The authors examined the frequency of thromboembolism and bleeding complications in cases of mechanical valve replacement during the past 5 years in the Tokyo area. There were 21 cases of thromboembolism and 15 cases of bleeding complications. Analyzing these cases with regard to anticoagulant therapy, 71% of the thromboembolism cases and 47% of the bleeding complication cases had 10∼25% result on the thrombotest at the time of the event. Consequently, in cases of mechanical valve replacement it is necessary to reevaluate the therapeutic range of the thrombotest results. This was a retrospective study of a TAS (The Tokyo area anticoagulation study for cardiac valve replacement by using PT-INR) trial and we intend to carry out a prospective study on the therapeutic range of the thrombotest and PT-INR.

A Case Report of Aortic Arch Replacement for Acute Dissection of Stanford Type A under 135 Minutes of Deep Hypothermic Circulatory Arrest Employing Retrograde Cerebral Perfusion / 日本心臓血管外科学会雑誌

A 54-year-old male with sudden back pain was diagnosed as having acute aortic dissection of Stanford type A. He underwent an aortic arch replacement under the deep hypothermic circulatory arrest and retrograde cerebral perfusion. During retrograde cerebral perfusion, the central venous pressure was maintained at 20mmHg, the perfusion flow rate was 400ml/min and the lowest rectal temperature was 19°C. The duration of retrograde cerebral perfusion was 135 min, but the patient recovered successfully without any evidence of neurological complications. This report suggests that retrograde cerebral perfusion associated with deep hypothermic circulatory arrest has the possibility to prolong the safety time limit of antegrade cerebral circulatory arrest up to 135min.

Surgical Treatment of Aortic Aneurysms in Hemodialysis Patients / 日本心臓血管外科学会雑誌

Surgical treatment of two abdominal and two thoracic aneurysms in hemodialysis patients were performed from 1991 to 1993. Two elective cases survived, but two emergency cases died. The causes of death were PMI and respiratory failure. Ruptured aneurysms are critical and probably result in higher mortality and morbidity than elective replacement of aneurysms. In view of the documented risk of rupture and current operative risk, we believe that elective surgical treatment of aneurysm is a much better treatment than following the aneurysms until they produce symptoms or significantly enlarge.

Coronary Artery Revascularization in Chronic Hemodialysis Patients / 日本心臓血管外科学会雑誌

We controlled the hemodilution and electrolyte levels during coronary artery revascularization in chronic hemodialysis patients by hemofiltration during the period of extracorporeal circulation. Subjects comprised 7 chronic hemodialysis patients (males, average age 53) undergoing coronary artery revascularization in our department from January 1988 to December 1989. All patients had been undergoing hemodialysis for chronic renal failure and in one patient, after admission, continuous ambulatory peritoneal dialysis (CAPD) was additionally performed. During surgery, the dialyzer was equipped with an extracorporeal circulation circuit and the electrolyte level and hemodilution were adjusted using transfusion (1, 270±372ml). A large infusion volume (12, 657± 3, 966ml) was maintained and removal of water was carried out by ultrafiltration. After surgery, all patients underwent hemodialysis twice or more by the 3rd day of recovery. Concentrations of electrolytes were maintained at appropriate levels throughout the day of surgery except for one case of postoperative hypokalemia, but no marked changes in hemodynamics were observed during and after surgery. Hemofiltration during extracorporeal circulation is safe and useful in coronary surgery because it is simpler and requires less time than hemodialysis.