To evaluate viability and severity of ischemically damaged myocardium, myocardial single emission tomography (SPECT) using 123I-BMIPP (BMIPP), a new tracer of myocardial metabolism of fatty acid, was performed before and after coronary artery bypass grafting (CABG). 201Tl myocardial SPECT (Tl) and left ventriculography (LVG) were also used. Thirty-three revascularized areas in eight patients were investigated. (1) Areas showing good redistribution on Tl and normal uptake on BMIPP indicated good viability and simple ischemic myocardium. Postoperative uptake of both tracers returned to normal levels. (2) Areas showing good redistribution on Tl and severely decreased uptake on BMIPP indicated jeopardized myocardium with severe ischemia. All such areas were seen in patients with unstable angina. Postoperative uptake of both tracers returned to normal levels. (3) Areas showing poor redistributionor severely decreased uptake on Tl and slight uptake on BMIPP indicating hibernating areas. Postoperative uptake became normal or better than preoperative uptake on Tl necrosis. However on BMIPP, the uptake was unchanged or recovered slightly. (4) Areas showing complete defect in Tl and BMIPP indicated necrosis and had no viability. Postoperatively the defect in both tracers were unchanged. Therefore, these areas required no revascularization. The ischemic state of myocardium could be assessed by evaluation of uptake patterns of BMIPP and Tl using myocardial SPECT. Therefore, using this new tracer of myocardial fatty acid metabolism “BMIPP”is useful for deciding culprit and viable lesions requiring coronary revascularization and evaluating therapeutical effects.

Combined surgery for left Subclavian artery revascularization and CABG was performed in a 74-year-old man with diabetes mellitus. The preoperative coronary angiogram showed critical stenoses in all three major branches, and arteriography revealed obstruction at the left proximal subclavian artery. Severe atherosclerotic calcification was acknowledged circumferentially in the ascending aorta and in the aortic arch. For this patient axillo-axillary crossover bypass grafting was performed first using and expanded PTFE graft, followed subsequently by off-pump CABG using all in situ grafts (right internal thoracic artery-left anterior descending artery (RITA-LAD), left internal thoracic artery-diagonal branch (LITA-diagonal branch), gastroepiploic artery-right coronary artery (GEA-RCA)). Postoperative recovery was smooth, with disappearance of significant pressure difference between both arms (preoperatively, 46mmHg). An angiogram on the 7th postoperative day showed a widely patent axillo-axillary bypass graft along with good flow of all three coronary grafts, in which LITA was visualized well through the axillo-axillary bypass graft. For complex atherosclerotic disease of the proximal aorta and incipient portion of neck vessels associated with severe coronary sclerosis, this technique is a suitable option.

This report describes 5 patients in whom extensive graft replacement was performed using a combination of median sternotomy with antero- or postero-lateral thoracotomy: 3 of them received replacement from the ascending to the descending thoracic aorta through the transverse aortic arch, and 2 of them received replacement from the transverse aortic arch to the descending thoracic aorta. Four of the 5 patients had catastrophic pulmonary bleeding during surgery and died immediately after the surgery. Histological investigations on 3 of the 5 patients revealed the presence of bleeding in bilateral alveola; edema in the pulmonary parenchymal tissues; and heavy bleeding extensively in the lung which was especially intensive in the pulmonary hilum and caused necrosis of that region in one case. We presume that long periods of total heparinization (extracorporeal circulation time>240min) performed during lateral thoracotomy, were the most important cause of the pulmonary bleeding. Other factors that could cause pulmonary bleeding are (i) avoidance of use of a double lumen endotracheal tube, (ii) pulmonary congestion due to heart failure during surgery, and (iii) pulmonary injury caused by surgical manipulation. We therefore consider that extensive graft replacement of the thoracic aorta through lateral thoracotomy using a pump-oxygenator, is associated with a high risk of pulmonary bleeding when it takes longer than 240min, and it is essential to perform the graft replacement in the possible shortest time.

The surgical results of 9 patients (group II) who were treated for thoracoabdominal aneurysm using left heart bypass combined with oxygenation were compared to those of 16 patients (group I) using left heart bypass without oxygenation. The left heart bypass time in group II was longer than that in group I, and the operations performed in group II were more extensive with more intercostal and lumbar arteries being reconstructed than those in group I. Nevertheless, bleeding associated with transfusion was less in group II than in group I. Intraoperatively, hypothermia and hypoxemia developed in 44% and 31%, respectively of group I, whereas neither of these conditions occurred in group II. There were three operative deaths in group I, compared with one in group II. Paraplegia was encountered in one patient of group I, but in none of the patients in group II. There were a few patients with respiratory failure or other organ failures in both groups. Our results showed that left heart bypass combined with oxygenation offered more stable and effective respiratory as well as circulatory support for a long duration compared to conventional left heart bypass without oxygenation in the surgical treatment of thoracoabdominal aortic aneurysm.

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.

Forty-four cases of ruptured abdominal aortic aneurysm were treated between January 1980 and December 1995. We classified the cases into three groups: Group I, 1980-1984; Group II, 1985-1989; and Group III, 1990-1995 and evaluated the surgical results, the preoperative states, the bleeding and blood transfusion volume and so on. The surgical results have improved every year and there were no surgical deaths during the past seven years. Most of the causes of previous surgical deaths were DIC (4 cases) and renal failure (3 cases). The volume of intraoperative bleeding was 7227.3±3293.4ml in Group I, 4176.0±2577.9ml in Group II and 1781.9±1877.0ml in Group III. The volume of intraoperative blood transfusion was 6975.5±2711.6ml in Group I, 4826.7±2596.6ml in Group II and 3542.4±1561.5ml in Group III. We decreased the volume of intraoperative blood transfusion significantly in Group III by using a Cell Saver. The surgical results have improved significantly due to the decrease of bleeding and blood transfusion under the rapid control of bleeding and the autotransfusion of shed blood using the Cell Saver. The technique of postoperative care also contributed to the more satisfactory results.

A 29-year-old man, who had undergone valvotomy for pure pulmonary stenosis at 6 months of age, was admitted to our institution for surgical treatment of a giant ascending aortic aneurysm and annuloaortic ectasia. Chest MRI revealed a 14-cm ascending aneurysm in contact with the sternum. After establishing femoro-femoral bypass for hypothermia, a left lateral thoracotomy was perfomed at the 4th intercostal space. Pulmonary artery cannulation was performed for left heart venting, and the proximal aortic arch was dissected for aortic cross-clamping. Median sternotomy was performed under circulatory arrest at 18°C and the aortic arch was opened. Under retrograde cerebral perfusion, the proximal arch was replaced by an artificial graft, and then aortic root replacement was completed using a composite graft under CPB. The postoperative course was uneventful, and the patient was discharged on the 37th postoperative day. He has been well without any complications. This case suggests that our method of approach to the giant aortic aneurysm with sternal adhesion and aortic regurgitation, and the use of extracorporeal circulation in view of the annuloaortic ectasia is effective and safe in case of reoperation.

We encountered two cases of infected aortic abdominal aneurysm with spondylodiskitis. Both cases were diagnosed on the basis of fever, back pain and pulsatile abdominal mass. A 69-year-old man, case 1, underwent in situ reconstruction 1 year from the onset, because the infection was controllable by antibiotics and he had diabetes mellitus. A 68-year-old man, case 2, underwent operation while his infection was still active, because of paralysis of the bilateral lower extremities, aggravated by invasion of the vertebrae by the abscess. To prevent artificial graft infection, he underwent axillo-femoral bypass, which was extra-anatomical reconstruction, after the infected aneurysm and vertebrae were removed during aortic clamping above the aneurysm and bilateral common iliac arteries. Each stump was sutured and anterior fixation of the vertebrae was performed using an iliac bone graft. The postoperative course of both patients was successful. These cases suggest that the timing and procedure of the operation for infected aortic abdominal aneurysm with spondylodiskitis should be decided depending on the activity of infection, complications, age and activity of daily life of patients.

Although sequential bypass with in situ arterial conduits (the left and right internal thoracic arteries; LITA and RITA, the right gastroepiploic artery; GEA) in coronary artery bypass grafting (CABG) is technically demanding, it is one of the most important procedures using a limited number of in situ arterial conduits to revascularize a wide area. In this report, we retrospectively investigated the clinical outcome of CABG with 4 or more distal anastomoses using only in situ arterial conduits. From December 1990 to May 1999, 62 patients underwent CABG with in situ arterial conduits, with at least one sequential bypass. There were 59 men and 3 women patients with mean age of 59.6 years (41 to 82 years). Mean postoperative follow-up period was 32 months (1 to 101 months). The total number of distal anastomoses was 4 (1 sequential bypass) in 54 patients, 4 (2 sequential bypasses) in 6 patients, 5 (1 sequential bypass) in 1 patient and 6 (3 sequential bypasses) in 1 patient. There were 5 emergency operations (8%), 37 patients (60%) had a history of myocardial infarction, 30 patients (48%) had diabetes mellitus and 6 patients (10%) had chronic renal failure and were on hemodialysis. Left ventricular ejection fraction was 40% or less in 15 patients (24%). There were no early deaths. Angiographic patency was satisfactory for each graft (sequential: individual, LITA 96.7%: 100%, RITA 100%: 100%, GEA 89.5%: 97.4%). Patency of a distal anastomoses of GEA was rather poorer than that of proximal (p=0.03). Three patients died during the follow-up period (all of them due to malignancy). The 5-year actuarial survival and cardiac event-free rate was 94.6% and 87.2%, respectively. In conclusion, although an indication of GEA sequential grafting needs further study, in situ arterial grafting with at least one sequential arterial conduit was associated with excellent results and achieved more complete revascularization with exclusive use of in situ arterial conduits in patients with diffuse coronary artery disease.