Mechanical Thrombectomy for Postoperative Stroke in a Patient with Acute Aortic Dissection Type A.

Mechanical thrombectomy has been proposed to expand the treatment time window and enhance revascularization. However, it is unclear whether its use can be extended to patients with occlusions in acute aortic dissection, especially the thoracic aorta. A 55-year-old man underwent graft replacement for acute aortic dissection type A. On postoperative day 2, he developed stroke and computed tomography showed occlusion of the right middle cerebral artery. Mechanical thrombectomy was performed by transbrachial approach. Although successful recanalization was achieved, he suffered hemorrhagic stroke. Since there is no other effective treatment and the neurologic outcome with conservative management is poor, we consider mechanical thrombectomy to be a viable therapeutic option for the treatment of postoperative stroke in patients with acute aortic dissection type A. However, further study is warranted regarding the safety of this technique.

Concomitant Resection of Left Ventricular Hemangioma and Lung Cancer With Ground-Glass Opacity.

We report a case of concomitant left ventricular tumor and lung lesion with ground-glass opacity without preoperative confirmation of malignancy. To obtain definitive diagnosis, a wedge lung resection was performed through a median sternotomy. After confirmation of a negative margin by frozen section, the cardiac tumor was resected through a left anterior ventriculotomy. Histopathologic analysis identified a rare cardiac hemangioma and an adenocarcinoma with pTis, N0, M0, stage 0. Postoperative recovery was uneventful with intact cardiopulmonary functions despite the risk of low cardiac output attributable to ventriculotomy.

A Case of Acute Type A Aortic Dissection with Double Aortic Arch.

Double aortic arch (DAA) is extremely rare in adults. A 71-year-old woman suffered from syncope, and an acute-type aortic dissection with a DAA accompanied by a massive pericardial effusion was shown in a non-enhanced computed tomography (CT). Enhanced CT was not performed because of her hemodynamic instability. She was rushed to the operating theater after immediate pericardiocentesis without more precise morphological evaluation. Ascending aortic replacement was performed by clamping both aortic arches without systemic circulatory arrest. She survived the operation, but her respiratory function was affected by tracheomalacia and remaining DAA with residual dissection.

A Case of Traumatic Retrograde Type A Aortic Dissection Accompanied by Multiorgan Injuries.

A 75-year-old woman was involved in a traffic accident and suffered retrograde type A aortic dissection, multiple rib fractures, and grade II hepatic injury accompanied by intraperitoneal bleeding. We performed total arch replacement using an open stent graft with cardiopulmonary bypass and circulatory arrest. This procedure requires anticoagulation and hypothermia, which are principally contraindicated in severe trauma patients. However, this situation was resolved by managing the patient non-operatively for 7 days, confirming the stabilization of other injured organs, and then performing the surgery. She required prolonged postoperative rehabilitation; however, she recovered steadily.

[Successful Repair of Chronic Expanding Hematoma after Coronary Artery Bypass Grafting by Lower Partial Sternotomy Approach;Report of a Case].

Chronic expanding hematoma (CEH) after coronary artery bypass grafting (CABG) is extremely rare. We reported a case of successful surgical repair of CEH through lower partial sternotomy approach. The patient was a 73-year-old man who underwent CABG. Fifteen years after the operation, he was admitted to referral hospital because of dyspnea on exertion. Echocardiography and computed tomography revealed a giant intrapericardial mass, which was pressing on the inferior wall of the ventricle. To avoid injury of the aorta and the patent bypass graft in the reentry of the chest, we selected lower partial sternotomy approach. The mass was encapsulated with thick fibrous membrane containing old degenerated coagula and was histopathologically diagnosed as CEH. Postoperative course was uneventful and diastolic heart failure was relieved.

[Successful Emergency Pulmonary Embolectomy in a Patient with Shock；Report of a Case].

The patient was a 48-year-old man, who had hemodynamic shock after orthopedic surgery. He was then diagnosed with right pulmonary artery embolism. Circulatory collapse remained, despite cardiac resuscitation. Therefore, he was treated with percutaneous cardiopulmonary support (PCPS) and intra-aortic balloon pumping (IABP). He was then transferred to our hospital and emergency pulmonary embolectomy was performed under cardiopulmonary bypass. The postoperative course was uneventful, and he was discharged without complications. Early diagnosis and early placement of PCPS and IABP allows safe transfer of patients and successful performance of emergency pulmonary embolectomy.

Mycotic Iliac Artery Aneurysm Caused by Clostridium difficile in a Patient with Axillobifemoral Bypass for Leriche Syndrome.

A 74-year old man on hemodialysis developed a mycotic aneurysm caused by Clostridium difficile. To the best of our knowledge, this is only the second case of such an aneurysm reported in the literature. He had previously undergone axillobifemoral bypass grafting because of symptomatic infrarenal aortic stenosis. Although no blood flow was detected in his occluded right common iliac artery, it expanded rapidly despite intensive antibiotic therapy. As the blood supply to the lower limbs was already secured, only resection of the infected arteries was performed.

Quadricuspid aortic valve with ascending aortic aneurysm: a case report and histopathological investigation.

We describe the case of a 69 year-old woman with a dilated ascending aorta, who presented with aortic valve regurgitation due to a quadricuspid aortic valve (QAV). There are only a few reports in the literature describing aortic replacement and subsequent aortic valve replacement for a malfunctioning QAV. We discuss the pathogenesis of the dilated ascending aorta in this patient and the indication for ascending aorta replacement in such cases.

A case of inferior mesenteric artery aneurysm with an occlusive disease in superior mesenteric artery and the celiac artery.

A 72 year-old man was referred to our hospital for treatment of a gradually expanding inferior mesenteric artery (IMA) aneurysm associated with an occluded superior mesenteric artery (SMA) and a severely stenosed celiac artery (CA). Using 64-slice computer tomography (CT), we were able to accurately define a precise collateral visceral circulation from the IMA to the SMA and the CA, greatly clarifying preoperative strategy. The aneurysm was subsequently removed, with revascularization of the SMA and the CA accomplished through grafts from the abdominal aorta using 6 mm polytetrafluoroethylene (PTFE) grafts.

Suppression of acute and chronic rejection by hepatocyte growth factor in a murine model of cardiac transplantation: induction of tolerance and prevention of cardiac allograft vasculopathy.

BACKGROUND: Although treatment with immunosuppressive agents has contributed to overcoming acute rejection and improving the midterm survival of transplanted hearts, cardiac allograft vasculopathy (CAV) has remained the main cause of primary graft failure. Recent approaches have shown that hepatocyte growth factor (HGF) exhibits cardiotrophic functions. We therefore addressed whether HGF would regulate acute and chronic rejection in cardiac transplantation. METHODS AND RESULTS: We used a murine heterotopic cardiac transplantation model between fully incompatible strains and administered 500 microg x kg(-1) x d(-1) HGF during the initial 14 days after transplantation. The HGF-treated allografts showed significantly prolonged survival (42.3+/-4.1 days, P<0.001) compared with the controls (11.1+/-0.6 days), with tolerance induction in 47.4%. Histopathologically, the number of infiltrating cells was significantly decreased and myocardial necrosis was less prominent with a reduction of apoptosis in the allografts by HGF treatment during acute rejection. In the long-term surviving allografts, HGF significantly inhibited the development of CAV and interstitial fibrosis. With respect to intragraft cytokine mRNA expression, HGF treatment reduced the early expression of interferon-gamma and enhanced the expression of transforming growth factor-beta1 during the acute phase and of interleukin-10 continuously through the acute phase to the chronic phase. CONCLUSIONS: Our findings demonstrate that HGF can prolong the survival of allografts by its cardioprotective and immunomodulative potencies. Thus, HGF administration may constitute a new therapeutic approach to preventing cardiac graft failure that has not been overcome by conventional immunosuppressive agents.

Egr-1 in vascular smooth muscle cell proliferation in response to allo-antigen.

BACKGROUND: Early growth response factor-1 (Egr-1) plays an important role in regulating multiple factors involved in the progression of vascular lesions. This study examined our hypothesis that Egr-1 plays a critical role in the early stage of chronic cardiac allograft rejection and in the proliferation of the smooth muscle cell response to alloantigen. MATERIALS AND METHODS: Antisense Egr-1 oligodeoxynucleotide (ODN) was ex vivo gene transfected into the donor hearts from DBA/2 mice, followed by heterotopic allografting into B10.D2 recipients. The allografts were harvested on day 30. Egr-1 and its target molecules, such as platelet-derived growth factor (PDGF)-A, basic fibroblastic growth factor (bFGF), vascular cell adhesion molecule (VCAM)-1, transforming growth factor (TGF)-beta and nonmuscle myosin heavy chain B (SMemb), were identified immunohistochemically, and the percentage of the lumen occluded by the intima was calculated. For the cell proliferation assay, sensitized T cells were harvested from B10.D2 recipients as stimulator and then added to the SMCs, which were harvested from DBA/2 mouse aorta. Cellular proliferation was measured and Egr-1 and its target gene expression were examined by real-time RT-PCR. RESULTS: Egr-1 and its target genes were expressed in the thickened intima from untreated recipients. Egr-1 antisense ODN inhibited not only Egr-1 expression but also its target genes and significantly suppressed intimal thickening of coronary arteries. Egr-1 antisense ODN also significantly inhibited cell proliferation and expressions of Egr-1 and Egr-1 target genes in a mixed cell culture model. CONCLUSION: We conclude that Egr-1 plays an important role in the formation of the cardiac allograft vasculopathy responding to alloantigens.

Significance of monocyte chemotactic protein-1 and thymidine phosphorylase in angiogenesis of human cardiac myxoma.

Angiogenesis is indispensable to tumor development and proliferation. The aim of this study was to investigate whether the expression of monocyte chemotactic protein-1 (MCP-1) and of thymidine phosphorylase (TP) correlates with the angiogenesis and clinicopathologic features in cardiac myxoma. Paraffin-embedded specimens of 17 resected cardiac myxomas were immunohistochemically stained for MCP-1, CC chemokine receptor-2 (CCR-2), TP, CD31, and CD68. Correlations among MCP-1 expression, TP expression, microvessel count (determined by CD31 staining), macrophage count (determined by CD68 staining), and the clinicopathologic features of the patients were analyzed statistically. Immunohistochemical analysis revealed that MCP-1 and TP were expressed in myxoma cells, as well as in stromal cells such as infiltrating cells, fibroblast-like cells and endothelial cells. CCR-2 was abundantly expressed in stromal infiltrating cells in all myxomas and occasionally in the endothelial cells. In the tumor stroma, the major source of MCP-1, TP and CCR-2 was macrophages, and the sites of positive staining for MCP-1, TP and CCR-2 matched in most of the myxomas. Statistical analysis revealed that the proportions of MCP-1-positive myxoma and stromal cells, and TP-positive myxoma and stromal cells significantly correlated with increased microvessel count. The proportions of MCP-1-positive myxoma and stromal cells significantly correlated with the proportion of TP-positive stromal cells. The mean microvessel count in myxomas with both high tumor and high stromal MCP-1 or TP expression was significantly higher than that in myxomas with low tumor and low stromal MCP-1 or TP expression. Small tumors (< or =55 mm in diameter) exhibited high MCP-1 or TP expression, and the microvessel count in small tumors was significantly higher than in large myxomas. Although the difference was not significant, myxomas with both high tumor and high stromal MCP-1 expression had a higher macrophage count than other myxomas. These results indicate that in cardiac myxoma, MCP-1 and TP may be regarded as important angiogenic signals accompanying growth.

Expression of matrix metalloproteinases in cardiac allograft vasculopathy and its attenuation by anti MMP-2 ribozyme gene transfection.

OBJECTIVE: Proliferation and migration of vascular smooth muscle cells (SMCs) causes intimal thickening during cardiac allograft vasculopathy (CAV). This process requires the degradation or remodeling of extracellular matrix (ECM) surrounding the cells. Imbalance between degradation and accumulation of ECM also contributes to the development of CAV. In this study, we investigated the contribution of matrix metalloprotenases (MMPs), enzymes regulating ECM turnover, to the development of CAV. METHODS: Donor hearts from male DBA mice were heterotopically transplanted to male B10.D2 recipient mice, and harvested at days 15 and 30 post transplantation. We examined expression MMP-2, -3, -9 and -13 of graft vessels using immunohistochemistry. To clarify the role of MMP-2 in CAV, anti MMP-2 ribozyme was delivered into donor hearts just before transplantation, mediated by a hemagglutinating virus of Japan-liposome complex to specifically suppress MMP-2 activity. RESULTS: All MMPs were immunopositive in SMCs from the slightly thickened neointima at day 15. In the advanced stage of intimal thickening at day 30, in addition to increased number of SMCs, accumulation of collagenous fibers was observed; expression of MMP-3, -9 and -13 was decreased. In contrast, MMP-2 expression remained distinctly positive throughout the progression of the vascular remodeling. After the gene transfer of MMP-2 ribozyme, luminal occlusion was significantly decreased compared to non-treated allografts [25.0+/-6.5 vs. 55.1+/-7.0% (P<0.05)] at day 30 post transplantation. CONCLUSION: MMP-2 is a principle MMP throughout the progression of the vascular remodeling in CAV. Anti MMP-2 therapy could therefore be one of the candidates for a supplemental therapy for CAV.