Tatsuro Asada

Retrograde cerebral perfusion versus selective cerebral perfusion as evaluated by cerebral oxygen saturation during aortic arch reconstruction

BACKGROUND Time limits for neuroprotection by retrograde cerebral perfusion (RCP) and selective cerebral perfusion (SCP) in aortic arch aneurysm repair or dissection are undergoing definition. METHODS Using near-infrared optical spectroscopy, changes in regional cerebrovascular oxygen saturation (rSO2) were compared between the two perfusion methods. RESULTS Immediately before cardiopulmonary bypass, baseline rSO2 was 63.9%+/-6.9% for the RCP and 66.1%+/-5.3% for the SCP group (no significant difference). As patients were core-cooled to 20 degrees C, rSO2 increased to 73.1%+/-8.8% and 74.1%+/-7.9% in the RCP and SCP groups, respectively. With circulatory arrest, rSO2 suddenly decreased. After starting cerebral perfusion, rSO2 returned to prearrest values in the SCP group but continued decreasing steadily in the RCP group, to levels below baseline after about 25 minutes. At the end of perfusion, rSO2 was 57.4%+/-12.2% for the RCP group and 71.7%+/-6.9% for the SCP group, and the ratio of rSO2 to baseline value was 0.89 for RCP and 1.08 for SCP despite a shorter brain perfusion time for RCP (38.8+/-18.0 versus 103.3+/-43.3 minutes). Three of 5 patients whose ratios of rSO2 to baseline at the end of brain protection were 0.7 or less had neurologic deficits. CONCLUSIONS Although SCP showed no clinically important time limitation, rSO2 continued to decrease with time during RCP. An rSO2 ratio less than 0.7 could represent a critical lower limit.

Skeletonization and harvest of the internal thoracic artery with an ultrasonic scalpel.

A new method to skeletonize and harvest the internal thoracic artery using an ultrasonic scalpel is presented. The technique is simple, safe, and minimally invasive. It is possible to obtain sufficient vessel length for anastomosis to most coronary arteries for bypass grafting.

Leriche Syndrome Surgical Procedures and Early and Late Results

During the past thirteen years, 29 patients underwent surgical intervention for Leriche syndrome. Fifteen patients (aged forty-two to seventy-two years, average 60.7 years) underwent anatomical bypass, and 9 of them whose thrombus was confined to the infrarenal aorta received a routine graft insertion. In the other 6 whose thrombus extended to the level of the renal arteries, an open thrombectomy of the juxtarenal aorta was first performed through a transection of the infrarenal aorta under renal ischemia (4-14 minutes, average 7). Twelve elderly or high-risk patients (aged sixty-eight to eighty-four years, average 75.3 years) underwent an axillobifemoral bypass, and another (continued on next page) 2 (fifty-eight and sixty years old, respectively) who had been operated on at an earlier time received an ascending aortobifemoral bypass. In cases of anatomical bypass, no graft has occluded and all patients but 1, who died of cerebral infarction, have an active life now. In cases of extraanatomical bypass, 5 of the 28 grafts occluded and only 6 patients have survived. The other 8 patients died of malignancy, atherosclerotic complications, or unknown causes. The 10-year survival rate was 92.9% and 29.5% in the anatomical bypass and extraanatomical bypass group, respectively. In Leriche syndrome, anatomical bypass is preferred to extraanatomical bypass if conditions permit. In the juxtarenal type, an open thrombectomy under renal ischemia is mandatory for anatomical bypass, and a transection of the infrarenal aorta facilitates this procedure. Because the patients with Leriche syndrome are elderly and harbor arte riosclerotic lesions, a careful follow-up is mandatory.

The problems of surgical treatment for cardiac myxoma and associated lesions

Twenty-four patients with cardiac myxomas consisting of 22 left and 2 right atrial myxomas were operated on. All myxomas were removed with an excision of the attachment walls using a cardiopulmonary bypass. Two myxomas required a partial cardiopulmonary bypass from the femoral vein to the artery prior to operation because they were on the verge of becoming stuck in the atrioventricular valves and potentially causing shock. For embolic complications of myxoma, the embolus of the external carotid artery was extirpated before undergoing cardiac surgery. In a patient with pulmonary infarction, the infarcted lung was resected simultaneously. Another patient with a cerebral infarction received a clipping of an aneurysm which later appeared in the infarcted area. For associated cardiac lesions, two patients underwent a coronary artery bypass graft and one mitral valve replacement with tricuspid annuloplasty. In the former two cases, the myxoma was removed prior to coronary artery bypass grafting because the use of retrograde coronary perfusion was considered to be sufficient to protect the heart. In the latter case, the removal of the myxoma first disclosed a significant mitral lesion which had been masked by the huge myxoma. All patients but one, who died of pneumonia, showed a good recovery. In this series, the problems of surgical treatment for cardiac myxoma and associated lesions are also discussed.

Surgical Treatment of Infective Endocarditis Complicated by Annular Infection and Cerebral Infarction

The surgical treatment of nine patients with infective endocarditis (IE) complicated by annular infection and five with IE complicated by cerebral infarction is described herein. In those with annular infection, after thorough débridement of the infected tissues, valve replacement was performed at the original position in five, at the supraannular position in three, and one underwent a translocation procedure. Aortic valve replacement was able to be performed at the original position in two patients by closing the defect at the aortic annulus with a patch after thorough débridement. The five patients who underwent original valve position replacement recovered well. Of the three who underwent supraannular position replacement, two died of septicemia after a redo operation, and one received pacemaker implantation. The patient undergoing the translocation procedure died of intestinal infarction. In the five patients who suffered cerebral infarction due to embolus of the vegetation, valve replacement was performed between 40 h and 5 months after its onset. Although one patient died of the rapid progression of brain damage, the other four are alive and well, including two who developed mycotic cerebral aneurysm in the infarcted areas. In conclusion, early surgery for IE is mandatory irrespective of active infection, due to the high mortality and morbidity associated with serious sequelae such as annular abscess or cerebral infarction.

Aortic regurgitation caused by rupture of the abnormal fibrous band between the aortic valve and aortic wall

This report documents the sudden onset of aortic regurgitation (AR) by an exceptional cause. A 68-year-old woman suddenly experienced general fatigue, and AR was diagnosed. One year later, we performed aortic valve replacement. At surgery, three aortic cusps with a larger noncoronary cusp had prolapsed along with a free-floating fibrous band that had previously anchored the cusp to the aortic wall. Its rupture had induced the sudden onset of AR. There was no sign of infectious endocarditis. We performed successful aortic valve replacement.

Mitral valve replacement through right thoracotomy after coronary arterial bypass grafting with functioning conduits.

A 67-year-old man who had undergone coronary artery bypass grafting 3 years previously suffered from severe mitral regurgitation associated with Streptococcal infective endocarditis. He was placed in New York Heart Association functional class III. Preoperative angiography demonstrated good opacification of all 3 conduits implanted in the previous operation. We replaced the mitral valve through an anterolateral right thoracotomy, approaching the mitral valve as an alternative to redoing sternotomy to minimize potential injury to patent grafts. His postoperative course was uneventful. After a 1-month course of antibiotics, the patient was discharged as New York Heart Association class II and at present, 3 months after discharge, is doing well. This approach is an effective alternative to redoing sternotomy for mitral valve operation, especially in patients undergoing a previous coronary arterial bypass grafting via median sternotomy.

Surgical removal of an intravascular ultrasonography catheter captured in a stent after percutaneous coronary intervention

A-79-year-old woman underwent percutaneous coronary intervention (PCI) to the right coronary artery (RCA) for effort angina, followed by intravascular ultrasonography (IVUS) to ascertain stent expansion. The IVUS catheter became entangled in the stent and could not be withdrawn from the outside. The patient was transferred to our hospital for its surgical removal. For the emergent surgery, we opened the stent region in the RCA and directly removed the IVUS catheter with the twisted stent. Additional coronary artery bypass grafting (CABG) involving three vessels was performed. She was discharged 42 days after surgery.

Perivalvular leakage 25 years after initial mitral valve replacement with a Björk-Shiley prosthesis

An 80-year-old woman had undergone initial mitral valve replacement using a Björk-Shiley mechanical valve owing to mitral stenosis 25 years earlier. Suddenly, she had anemia and an increased lactic dehydrogenase (LDH) level. Transesophageal echography (TEE) showed perivalvular leakage. In a redo operation, two side-by-side stitches of the valve on the posterior annulus were loosened without cutting and the sewing cuff at that site was floated over the annulus, leading to the perivalvular leakage. The valve was easily removed; and round, hard, degenerative calcified tissue composed of remnant mitral valve in the suture site during the initial operation was found just under the sewing cuff. After resection of this calcified round tissue, a 25-mm bioprosthesis was put in place. Her postoperative recovery was uneventful, and 47 days after surgery she was discharged without perivalvular leakage or anemia.

Surgical Treatment of Abdominal Aortic Aneurysm Due to Vasculo-Behqet's Disease A Case Report

A thirty-two-year-old woman was operated on for abdominal aortic aneurysm due to vasculo-Behqets disease. Her aortography showed an aneurysm of curious eggplant-like configuration. At operation, the aneurysm was found to be adhered to the surrounding organ with the severely thickened wall. The diseased aorta was replaced with Y-shaped Dacron graft. Three anastomosis sites were apart from the inflammation and were rolled up with the Teflon felt for reinforcement. Pathology of the diseased wall showed an infiltration of the inflammatory cells with the small-vessel vasculitis due to Behqets disease. She has had an uneventful postoperative course with a tapering corticosteroid therapy.