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A 68-year-old woman exhibited an increasingly protruding mass on the left heart border on chest X-ray. Transthoracic echocardiography revealed an echo-free mass in the anterior pericardial space. Transesophageal echocardiography revealed blood flow from the proximal left anterior descending coronary into a large coronary artery aneurysm measuring 61 mm × 51 mm in diameter and a quadricuspid aortic valve with a small cusp between the left and right coronary cusps. Coronary angiography demonstrated the presence of a coronary aneurysm connected to the proximal left coronary anterior descending artery. A giant coronary artery aneurysm and pulmonary artery fistulas extending from the left and right coronary arteries were confirmed by surgeons and successfully treated with surgery.

Purpose Extracorporeal circulation circuits used in cardiopulmonary bypass surgeries are increasingly being coated with polymer materials to reduce the thrombogenicity of extracorporeal devices. However, a haemoconcentrator, which corrects haematocrit and electrolyte imbalances, is not coated with polymers. In this study, we sought to assess the filtration performance of polymer-coated haemoconcentrators in order to obtain insight into their prospects for use in clinical applications. Methods In vitro experiments were performed to evaluate the water pressure and flow properties of polymer-coated haemoconcentrators by comparing 3 polymer-coated haemoconcentrators with 3 non-coated haemoconcentrators. The cross-sectional surfaces of both types of haemoconcentrators were observed using a scanning electron microscope (SEM). Results The slopes of the regression lines for estimating the filtrated fluid flow as a function of the transmembrane pressure were 6.286 ± 0.320 for polymer-coated haemoconcentrators and 3.712 ± 0.170 for non-coated haemoconcentrators. These slopes were found to be significantly different and indicate that the filtration velocity is enhanced in polymer-coated haemoconcentrators over that in non-coated haemoconcentrators. However, the hollow fibre damage observed by SEM was not shown to contribute to higher filtration flow in the polymer-coated haemoconcentrator. Taking these results into consideration, we hypothesise that a polymer coating makes a foreign surface on a hollow fibre slippery, owing to the hydrophobicity of the polymer, thereby enhancing the velocity of the filtration. Conclusions The results of this preliminary investigation suggest that a polymer coating can enhance the filtration performance of a haemoconcentrator and that polymer-coated haemoconcentrators might be useful in clinical applications.

Objective: In order to determine whether critical intercostal artery is present in the aneurysm during descending thoracic or thoracoabdominal aortic surgery, changes of transcranial motor-evoked potentials (Tc-MEPs) were monitored following infusion of cold blood into the aorta as an adjunct 'on-site assessment'. Accuracy of this method was evaluated. Methods: Fourteen patients were examined for Tc-MEPs changes following infusion of cold blood (4 °C, 300-450 ml) into the aneurysm. The intercostal arteries in the aneurysm were reconstructed when the Tc-MEPs amplitude decreased to below 50% of the baseline within 3 min after cold blood infusion. When the amplitude did not decrease, every intercostal artery in the aneurysm was ligated. Results: The Tc-MEPs amplitude did not decrease in eight cases (57%), while it decreased in six cases (43%). In the former, no case presented with paraplegia despite every intercostal artery being ligated. In the latter, the amplitude recovered after reconstruction in four patients, who had no paraplegia postoperatively. In the remaining two cases, however, the amplitude did not recover: one died of multiple organ failure with postoperative assessment unfeasible; the other developed paraplegia following surgery. Except one case with operative death, both sensitivity and specificity of our criteria with cold blood infusion was 100% in this series. Conclusions: Cold blood infusion into the clamped segment of aorta accelerates Tc-MEPs changes and can possibly reduce ischemic insults of spinal cord during diagnostic process, while it accurately detects presence of critical intercostal artery in the segment. This method appears to be promising adjunct on-site assessment.

MIDCABと大腸癌の一期手術を行い良好な経過を得たので報告する. 症例は81歳. 女性. 労作時胸痛と血便を主訴とし, 大腸内視鏡検査で横行結腸に出血を伴ったボールマン2型の大腸癌を認め, 冠動脈造影検査でLAD Seg 6の just proxymal から long lesion の狭窄を認めた. LADの吻合予定部位は蛇行し, 心筋内走行でないと推測されたため, MIDCAB可能と判断し, 大腸癌手術との一期手術を行った. まず左前胸部小切開で左内胸動脈をLADにバイパスし, ついで上腹部正中開腹で横行結腸切除およびリンパ節郭清を行った. 手術時間は, MIDCABに2時間10分, 大腸癌手術に1時間20分で, 計3時間30分であった. 術後翌日にICUから一般病棟に転棟し, 術後冠動脈造影検査でLITAの開存を確認した. 横行結腸切除の病理組織検査は, moderate differenciated adenocarcinoma, ss, n1, Po, Mo stage 3a であった. 術後15日目に退院となった.

ObjectiveThis study tested to see if trehalose, a cytoprotective disaccharide, protects against spinal cord ischemia in a rabbit model.MethodsThe infrarenal aorta was mobilized in four groups of 10 rabbits. In groups I, II, and III, it was clamped proximally and distally for 20 minutes. In group I, the clamped aorta was infused at 2.5 L/min for 2 hours with lactated Ringer's (LR) solution. In group II, the clamped aorta was infused with 5% trehalose in LR. LR was administered intravenously (2.0 mL/min) in groups I and II starting 30 minutes before clamping. In group III, 5% trehalose in LR was infused intravenously only. Group IV was a sham-operated control group without aortic clamping. At 8, 24, and 48 hours after reperfusion, hind limb function was scored using the Tarlov score (paralysis = 0, perceptible joint movement = 1, good joint movement but unable to stand = 2, able to walk = 3, normal = 4). Histologic analysis and electron microscopy were performed on anterior horn cells.ResultsThe Tarlov scores in groups I, II, and III were, respectively, 1.1 ± 1.4, 3.5 ± 0.5, and 2.9 ± 0.9 at 8 hours; 0.8 ± 1.2, 3.9 ± 0.3, and 2.9 ± 0.9 at 24 hours; and 0.6 ± 0.7, 3.9 ± 0.3, and 2.7 ± 0.9 at 48 hours after reperfusion. Group IV scores were normal (4 ± 0) at all assessments. These scores were higher in groups II and III than in group I (P < .01) at all assessments. Scores at 24 and 48 hours were higher in group II than in group III (P < .05). In group III, delayed paraparesis developed in one rabbit at 24 hours and in two more at 48 hours. Histopathologic analysis showed the number of normal neurons was higher in groups II (P < .0001), III (P = .006), and IV (P < .0001) vs group I. Electron microscopy confirmed preserved neuronal cell ultrastructure in rabbits with normal limb function.ConclusionsTransaortic trehalose infusion was protective against paraplegia, whereas intravenous trehalose reduced spinal cord ischemia. This study was preliminary and further studies are needed.Clinical RelevanceSpinal cord injury after surgical repair of the thoracic or thoracoabdominal aorta is a disastrous complication. Recently, many kinds of adjunctive therapy have been reported to be successful, including our previous reports of cold saline and free-radical scavengers in a rabbit model of spinal cord ischemia; however, some rabbits still became paraplegic. The total prevention of paraplegia due to spinal cord ischemia may require the development of a more effective adjunct. Trehalose, a unique nonreducing disaccharide, stabilizes cell membranes under various stressful conditions such as heat, freezing, osmotic shock, and dehydration. Trehalose has been used clinically as a solution for lung preservation in transplantation. This study demonstrated the protective effect of a trehalose infusion into the clamped segment of the aorta or transvenously to prevent spinal cord damage after spinal cord ischemia in an animal model. Further research is needed, but the results of this study may be applicable not only to open surgery but also to thoracoabdominal endovascular repair.

ObjectiveDelayed paraplegia after operation on the thoracoabdominal aorta is considered to be related to vulnerability of motor neurons to ischemia. Previous studies have demonstrated the relationship between neuronal vulnerability and endoplasmic reticulum (ER) stress after transient ischemia in the spinal cord. The aim of this study was to investigate whether sodium 4-phenylbutyrate (PBA), a chemical chaperone that reduces the load of mutant or unfolded proteins retained in the ER during cellular stress, can protect against ischemic spinal cord damage.MethodsSpinal cord ischemia was induced in rabbits by direct aortic cross-clamping (below the renal artery and above the bifurcation) for 15 minutes at normothermia. Group A (n = 6) was a sham operation control group. In group B (n = 6) and group C (n = 6), vehicle or 15 mg/kg/h of sodium 4-PBA was infused intravenously, respectively, from 30 minutes before the induction of ischemia until 30 minutes after reperfusion. Neurologic function was assessed at 8 hours, and 2 and 7 days after reperfusion with a Tarlov score. Histologic changes were studied with hematoxylin-eosin staining. Immunohistochemistry analysis for ER stress-related molecules, including caspase12 and GRP78 were examined.ResultsThe mean Tarlov scores were 4.0 in every group at 8 hours, but were 4.0, 2.5, and 3.9 at 2 days; and 4.0, 0.7, and 4.0 at 7 days in groups A, B, and C, respectively. The numbers of intact motor neurons at 7 days after reperfusion were 47.4, 21.5, and 44.9 in groups A, B, and C, respectively. There was no significant difference in terms of viable neurons between groups A and C. Caspase12 and GRP78 immunoreactivities were induced in motor neurons in group B, whereas they were not observed in groups A and C.ConclusionReduction in ER stress-induced spinal cord injury was achieved by the administration of 4-PBA. 4-PBA may be a strong candidate for use as a therapeutic agent in the treatment of ischemic spinal cord injury.Clinical RelevanceSpinal cord injury following surgical repair of thoracic or thoracoabdominal aorta is a disastrous complication. Previous studies have demonstrated the relationship between neuronal vulnerability and endoplasmic reticulum (ER) stress after transient ischemia of spinal cord. Sodium 4-phenylbutyrate (4-PBA) is a low molecular weight fatty acid that has been approved for clinical use as an ammonia scavenger in children with urea cycle disorders and for treatment of sickle cell disease and thalassemia. A number of investigators have recently reported utilization of 4-PBA as a chemical chaperone to reverse the mislocalization and/or aggregation of proteins associated with human disease. The 4-PBA of therapeutic dose has low toxicity and uniquely penetrates well into cerebrospinal fluid. In this study, we investigated whether intravenous administration of 4-PBA is beneficial to protecting the spinal cord against ischemic damage in a rabbit model. Spinal cord ischemia was induced by direct aortic cross-clamping while 4-PBA of therapeutic dose was infused intravenously. In this simple and less invasive model, reduction in ER stress-induced spinal cord damage was achieved by intravenous 4-PBA. Our results indicate that 4-PBA of therapeutic dose can be a promising strategy, which is clinically feasible without significant adverse effects. Although further investigations are mandatory before it is applied to the clinical practice, such as optimal timing or route for administration 4-PBA, intravenous administration of 4-PBA may be a new candidate as a therapeutic agent for protecting the spinal card against ischemic damage in thoracoabdominal aortic surgery.