Retrograde cerebral perfusion has been a useful technique for preventing brain damage during hypothermic circulatory arrest. To determine the optimum conditions for retrograde cerebral perfusion utilizing a fluorescence vital microscope, male Wistar rats weighing 100 to 300g were used for infusing saline with contrast medium (0.01% FITC-albumin) through the external jugular vein. A closed cranial window was prepared over the pial surface of the brain at the medial part of the right parietal cortex in order to observe the blood flow of tributaries from the middle cerebral artery to the superior cerebral vein. Intracranial pressure was controlled at 3±2cmH₂O for comfortable visualization. The observation of retrograde cerebral perfusion was performed under hypothermic conditions. Cerebral blood flow could not be observed under retrograde pressure of 5-15mmHg, mainly due to venovenous shunt flow. But retrograde cerebral perfusion was observed with a driving pressure of 15-30mmHg, and flow velocity measured by the video tracing method (n=5) in arterioles (mean diameter 37±10μm) was -12±5μm/sec, in venules (mean diameter 64±17μm) was -14±9μm/sec, which was 405±92μm/sec and 220±150μm/ sec under hypothermic beating heart conditions respectively. Under retrograde pressure of 30-50mmHg, cerebral microcirculation was deteriorated with increasing cerebral volume, and cerebral blood flow was consequently interrupted. In conclusion, the optimal condition for retrograde cerebral perfusion was determined under retrograde perfusion pressure of 15-30mmHg and intracranial pressure of 3±2cmH₂O, whenever cerebral microcirculation from venule to arterioles was best. Retrograde cerebral perfusion has some advantage for cerebral protection compared with hypothermic circulatory arrest, but might not supply sufficient cerebral blood flow to prevent brain damage.

Infected abdominal aortic aneurysm is uncommon, but it has a grave prognosis. We report a case of infected abdominal aortic aneurysm with localized dissection that was preoperatively given antibiotics for 1 month, followed by an anatomical vascular reconstruction with a prosthetic graft wrapped with a pedicled omental flap. A 48-year-old man with uncontrolled diabetis mellitus was admitted with fever, appetite loss, and pulsating abdominal pain. Abdominal CT revealed a saccular aneurysmal change in the infrarenal aorta and weakly enhanced surrounding soft tissue density. Two lumens were clearly enhanced in the aneurysm. Klebsiella pneumoniae infection was diagnosed on the basis of blood culture. Pathologically, suppurative inflammation was confirmed in the surrounding tissue and dissection of the media of the saccular aneurysmal wall was indicated. After administration of antibiotics for 1 month, both clinical and laboratory indications of inflammatory reaction improved. The aneurysm was then almost completely resected and replaced with a Y-shaped prosthetic graft covered with a pedicled omental flap. The postoperative course was uneventful. After surgery, antibiotics were administered for 3 more months. The patient is now surviving and has no symptoms 6 months after operaion. Complete removal of the infected lesion and long-term follow-up with antibiotic chemotherapy are important for this situation.

We performed surgical correction of a single atrium in a 46-year-old man, who had suffered from congestive heart failure (NYHA II) and pulmonary hypertension (58/23 (36) /mmHg). An intra-atrial shunt (L-R 71%, R-L 14%) due to single atrium and mild mitral and tricuspid regurgitation were detected. The operation consisted of making a new atrial septum with an autologous pericardial patch and direct mitral cleft suture. The post-operative course was uneventful.

Injury to the thoracic aorta is often fatal. We encountered a case of aortic rupture caused by a traffic accident. A 20-year-old man was transferred to our hospital because of right elbow fracture and enlargement of the upper mediastinum on X-ray. We diagnosed aortic isthmus rupture by chest CT with enhancement. He did not have chest pain, but complained of severe pain in the right elbow. His hemodynamic condition was stable, but his right arm become swollen with increasing sensory disturbance. Chest CT and blood cell count showed no interval change between results at a previous hospital and ours. So we decided to operate on his right arm before aortic rupture. After the open reduction of his fractured elbow, pleural effusion increased although his hemodynamic condition was stable. Then the descending aorta was replaced under partial cardio-pulmonary bypass. His post-operative course was uneventful.

We encountered a rare case of aortic regurgitation due to rheumatoid arthritis. A 53-year-old man was admitted with severe heart failure due to aortic regurgitation. He had been treated for rheumatoid arthritis for 5 years with methotrexate. After treatment for heart failure, his aortic valve was successfully replaced with an Omnicarbon prosthetic valve. Histopathological examination of the excised aortic valve showed rheumatoid granuloma. His post-operative course was uneventful.

A 53-year-old man was admitted to Jichi Medical School Hospital because of low back pain and respiratory distress. Echocardiography revealed mitral valve regurgitation and mitral vegetations, and MR imaging showed destructive change in the lumbar vertebrae. The low back pain and inflammatory activity subsided with administration of antibiotics, but regurgitation-induced heart failure was medically intractable. The patient underwent mitral valve replacement with a bicarbon valve. The mitral valve showed destructive change with infective vegetation. Microbiologic study of preoperative blood samples and resected valve did not show any organism. Antibiotics were given for another 6 weeks. As of the last follow-up observation at 18 months, the patient was doing well.

A case of 38-year-old woman with corrected transposition of great arteries is reported. She was admitted for acute cardiac failure caused by not only the left-side atrioventricular regurgitation for the ruptured chordae tendineae, but also the right-side one. We have to perform double valve replacement emergently due to the progression of biventricular failure. Very few reports have described a surgical repair of the right-sided valve replacement. The postoperative course was favorable.

A total of 961 patients underwent coronary artery bypass grafting (CABG) between 1982 and 1991, and we investigated perioperative cerebral infarction. The average age of operation in these case was 65±4 years. There was 9 patients with hypertension, 7 with diabetes mellitus and 5 with hyperlipidemia. Concerning cerebral infarction, there were 3 patients with multiple infarction, 6 with infarction of the mid cerebral artery area, 1 with infarction of posterior cerebral artery area, 1 with infarction of posterior cerebral artery area, 1 with infarction of pons and 1 with infarction of the ophthalmic artery. The courses of infarction involved atherosclerosis, hypoperfusion during cardiopulmonary bypass, thrombosis due to arterial fibrillation and thrombus on the left ventricular wall. Three patients who had critical cerebral infarction died after CABG. We consider that avoid perioperative cerebral infarction preoperative atherosclerosis, thrombus and to choose the proper procedure of the operation.

Coronary artery bypass grafting using hypothermic circulatory arrest and ventricular fibrillation without aortic cross clamping in 6 patients with severely calcified aortas is described. The use of hypothermic circulatory arrest or ventricular fibrillation has not been established in coronary artery bypass grafting. We recently used aortic no-touch technique in 6 patients. All patients were supported and cooled with cardiopulmonary bypass, and circulatory arrest was performed in 3 patients. With the exception of one hemodialysis patient, 5 patients survived without neurological deficit. We think the aortic no-touch technique is safe and reliable in coronary artery bypass grafting with severe calcified aortas.

The effectiveness of recombinant human erythropoietin (rHuEPO) was evaluated in elderly patients who underwent coronary artery bypass grafting. A total of 133 patients were divided into three groups: those who were 70 years of age or older and received rHuEPO (group I; n=32), those who were also 70 years of age or older but did not receive rHuEPO (group II; n=35), and those who were 60 years or younger and received rHuEPO (group III; n=66). In 87.5% of group I, 42.9% of group II, and 98.5% of group III, homologous blood transfusion could be avoided. The percentage of patients without homologous blood transfusion was significantly higher in group I than in group II (p<0.001). The rate of homologous blood transfusion was significantly higher in group I than in group III (p<0.05), but rHuEPO had equal effects in terms of increase in hemoglobin level in the two groups. Furthermore, in patients without anemia, the rate of homologous blood transfusion was almost the same in the two groups. In conclusion, the administration of rHuEPO enables even elderly patients to undergo coronary artery bypass grafting without homologous blood transfusion.