Moderate and deep hypothermia produces hyporesposiveness to phenylephrine in isolated rat aorta.

BACKGROUND: Moderate and severe hypothermia with cardiopulmonary bypass during aortic surgery can cause some complications such as endothelial cell dysfunction or coagulation disorders. This study found out the difference of vascular reactivity by phenylephrine in moderate and severe hypothermia. METHODS: Preserved aortic endothelium by excised rat thoracic aorta was sectioned, and then down the temperature rapidly to 25℃ by 15 minutes at 38℃ and then the vascular tension was measured. The vascular tension was also measured in rewarming at 25℃ for temperatures up to 38℃. To investigate the mechanism of the changes in vascular tension on hypothermia, NG-nitro-L-arginine methyl esther (L-NAME) and indomethacin administered 30 minutes before the phenylephrine administration. And to find out the hypothermic effect can persist after rewarming, endothelium intact vessel and endothelium denuded vessel exposed to hypothermia. The bradykinin dose-response curve was obtained for ascertainment whether endothelium-dependent hyperpolarization factor involves decreasing the phenylnephrine vascular reactivity on hypothermia. RESULTS: Fifteen minutes of the moderate hypothermia blocked the maximum contractile response of phenylephrine about 95%. The vasorelaxation induced by hypothermia was significantly reduced with L-NAME and indomethacin administration together. There was a significant decreasing in phenylephrine susceptibility and maximum contractility after 2 hours rewarming from moderate and severe hypothermia in the endothelium intact vessel compared with contrast group. CONCLUSION: The vasoplegic syndrome after cardiac surgery might be caused by hypothermia when considering the vascular reactivity to phenylephrine was decreased in the endothelium-dependent mechanism.

Haemodynamic alterations in cerebral blood vessels after carotid artery revascularisation: quantitative analysis using 2D phase-contrast MRI.

OBJECTIVES: This study was conducted to evaluate the effect of revascularisation, whether revascularisation improves total cerebral blood flow volume (FVTCBF), and how cerebral veins would respond to altered FVTCBF. METHODS: The 39 carotid artery stenoses in 37 patients who underwent revascularisation including 32 stentings and 7 endarterectomies were included in this prospective study. From the two-dimensional phase-contrast (2D-PC) MRI acquired before and after revascularisation, the flow volumes (FVs) of the arteries and veins were compared using paired t-test. The relationships between these parameters were correlated using Pearson's correlation coefficient. RESULTS: The mean FV in the treated carotid artery (proportion of treated artery among total FV) increased from 162.06 ml/min (25.80 %) to 267.71 ml/min (37.21 %; P < 0.001). Revascularisation increased the FVTCBF of patients from 638.66 ml/min to 716.72 ml/min (P < 0.001). The FV of the internal jugular veins, superior sagittal and straight sinuses (FVSS + SSS), and transverse sinuses increased after revascularisation (P < 0.05). Positive relationships were shown between the FVTCBF and the FVSS + SSS (r = 0.584-0.741, P < 0.001). CONCLUSIONS: Revascularisation improves the FVTCBF by increasing the FV in the treated carotid artery. The venous drainages are closely linked to FVTCBF. 2D-PC-MRI is a feasible method for evaluating comprehensively the haemodynamic improvement after revascularisation. KEY POINTS: • Revascularisation may be beneficial in ischaemic strokes due to carotid artery stenosis. • Revascularisation of the affected artery increases total cerebral blood flow volume ( FV TCBF). • Cerebral venous drainage, closely linked to FV TCBF, is also improved. • Two-dimensional phase-contrast MRI can comprehensively assess these haemodynamic improvements after carotid revascularisation.

Cystic Mass on Right Atrium of Unusual Form of Chiari's Network: A Case Report.

Chiari's networks are present in 1.5% to 4% of the population. They are a congenital disease characterized by a remnant of the right valve of sinus venosus and rarely have clinical significance. Chiari's network, as the name implies, has network-like shape, but there are other forms of appearance. We have experienced a case of a 60-year-old woman who had a cystic mass on the right atrium. Surgical treatment was performed forthe mass removal and differential diagnosis of the mass. There was no evidence of other tumor, but Chiari's network. As cystic form of Chiari's network have not been reported before, it is the first report of cystic form of Chiari's network.

Algal fucoidan, unlike heparin, has thrombolytic activity in a murine arterial thrombosis model.

Thrombolytic effects of fucoidans were investigated in the FeCl3-induced arterial thrombus mouse model and compared with heparin and tissue plasminogen activator (t-PA). Thrombosis model was made by applying 5% FeCl3 on the carotid artery of a Balb/c mouse. Twenty minutes after complete occlusion, a couple of test agents including fucoidan were infused into each mouse group with various doses intravenously, before measuring the time to reperfusion. The occluded arteries were reperfused 37.5 ± 12.4 min after administration of unfractionated fucoidan from Undaria pinnatifida sporophylls (UPS-UF) with a dose of 100 mg/kg. In the mice given either a low-molecular-weight UPS fucoidan or fucoidan source from Fucus vesiculosus (FV-UF), reperfusion was delayed at 55.0 ± 8.0 min with a higher reperfusion effective dose (RED) of 1 g/kg or at 63.3 ± 7.2 at RED of 200 mg/kg, respectively. In the control mice given t-PA of 15 mg/kg, reperfusion occurred at 24.8 ± 6.5 min after administration. In contrast, reperfusion was not observed in the occluded mice given heparin (P < 0.001) in the range of 60-1000 mg/kg. Minimal injection of fucoidan in addition to a given t-PA-enabled restoration of blood flow in the blocked artery without reocclusion at 17.2 ± 2.3 min postinjection (P < 0.002). In conclusion, algal fucoidan has both thrombolytic activity and a stimulatory effect on the thrombolytic activity of t-PA in a dose-dependent manner at an arterial thrombosis model.

Traumatic Aortic Injury: Single-center Comparison of Open versus Endovascular Repair.

BACKGROUND: Conventional open repair is a suboptimal therapy for blunt traumatic aortic injury (BTAI) due to the high postoperative mortality and morbidity rates. Recent advances in the thoracic endovascular repair technique may improve outcomes so that it becomes an attractive therapeutic option. MATERIALS AND METHODS: From August 2003 to March 2012, 21 patients (mean age, 45.81 years) with BTAI were admitted to our institution. Of these, 18 cases (open repair in 11 patients and endovascular repair in 7 patients) were retrospectively reviewed and the early perioperative results of the two groups were compared. RESULTS: Although not statistically significant, there was a trend toward the reduction of mortality in the endovascular repair group (18.2% vs. 0%). There were no cases of paraplegia or endoleak. Statistically significant reductions in heparin dosage, blood loss, and transfusion amounts during the operations and in procedure duration were observed. CONCLUSION: Compared with open repair, endovascular repair can be performed with favorable mortality and morbidity rates. However, relatively younger patients who have acute aortic arch angulation and a small aortic diameter may be a therapeutic challenge. Improvements in graft design, delivery sheaths, and graft durability are the cornerstone of successful endovascular repair.

Severe Mitral Regurgitation due to Traumatic Anterolateral Papillary Muscle Rupture: A Case Report.

A 29-year-old man was admitted for abrupt dyspnea and hemoptysis. An echocardiogram revealed severe mitral regurgitation due to papillary muscle rupture for which an emergency mitral valve replacement operation was performed 4 days after admission. Herein, we report our experience with this case along with a review of the literature.

An antithrombotic fucoidan, unlike heparin, does not prolong bleeding time in a murine arterial thrombosis model: a comparative study of Undaria pinnatifida sporophylls and Fucus vesiculosus.

The antithrombotic activities and bleeding effects of selected fucoidans (source from either Undaria pinnatifida sporophylls or from Fucus vesiculosus) have been compared with heparin in the ferric chloride-induced arterial thrombus mouse model. Thrombosis was induced by applying 5% ferric chloride for 3 min on the carotid artery region of Balb/c mouse. Five minutes prior to thrombus induction, mice were infused through the tail vein with either saline (control) or polysaccharides. Either fucoidan or heparin was dosed at 0.1, 1.25, 2.5, 5.0, 10, 25, or 50 mg/kg intravenously (i.v.) The carotid blood flow was monitored until more than 60 min post-thrombus induction. Mouse tail transection bleeding time was measured up to 60 min after making a cut in the mouse tail. Both antithrombotic and bleeding effects were observed in a dose-dependent manner for both fucoidans and heparin. Thrombus formation was totally (reflected by Doppler flow meter) inhibited at either 5 or 50 mg/kg of unfractionated Undaria fucoidan or a low-molecular-weight Undaria fucoidan fraction, respectively, without prolonging the time-to-stop bleeding compared with the control (p < 0.01). The total inhibition of thrombus formation was observed for unfractionated Fucus fucoidan at 25 mg/kg where the time-to-stop bleeding was still significantly prolonged, by as much as 8 ± 1.7 min (p < 0.02). In contrast the heparin-treated group showed total inhibition of thrombus formation even at a small dose of 0.8 mg/kg (400 IU) at which bleeding continued until 60 min. In conclusion algal fucoidans are highly antithrombotic without potential haemorrhagic effects compared with heparin in the arterial thrombus model, but this property differs from algal species to species, and from the molecular structure of fucoidans.

Floating Thrombus in the Ascending Aorta of the Patient with Systemic Sclerosis - A case report -.

Aortic thrombi are important because it can cause the central and peripheral embolizations. Aortic thrombi can occur anywhere in the aorta but extremely rare in ascending aorta without atherosclerosis, aneurysm, cardiosurgical or traumatic state. Systemic sclerosis (SSc) is an autoimmune disorder of connective tissue and it can involve multisystem. Enhanced coagulation pathways, decreased fibrinolysis, and endothelial dysfunction probably contribute to vascular events in SSc. We report a case of a highly mobile thrombus in the ascending aorta, presented as an acute embolic stroke in the patient with systemic sclerosis. Surgical removal was performed to prevent recurrent embolic events.

A case of type B dissecting aneurysm involving right sided aorta with Kommerell's diverticulum.

A right-sided aortic arch (RAA) is a rare congenital anomaly, and Stanford type B dissection aneurysms involving this anomaly is also uncommon. Surgical approaches to dealing with an RAA are complicated by the unusual anatomical features of the condition. Here we report the case of a 47-year-old male who had a type B dissecting aneurysm involving an RAA with Kommerell's diverticulum. Graft replacement was successfully performed with an uneventful postoperative course.

Effect of NF-κB decoy oligodeoxynucleotide on LPS/high-fat diet-induced atherosclerosis in an animal model.

Atherosclerosis is a chronic inflammatory process occurring in the walls of arteries, in large part due to the accumulation of inflammatory cells. This study was conducted to determine the effect of nuclear factor (NF)-κB decoy oligodeoxynucleotide (ODN) in an atherosclerosis animal model. The mice received i.p. injections of lipopolysaccharide (LPS, 2 mg/kg) three times a week to induce atherosclerotic change, and fed an atherogenic diet for 12 weeks. NF-κB decoy ODN (0.4 mg/kg) was injected into the tail vein. Treatment with NF-κB decoy ODN decreased pro-inflammatory cytokines, tumour necrosis factor (TNF)-α and interleukin (IL)-1ß and inflammatory markers, vascular adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1, in the LPS/Fat-induced mice. In addition, the expression of proteins related to fibrosis, transforming growth factor (TGF)-ß1 and fibronectin were markedly decreased in the mice treated with NF-κB decoy ODN compared with the LPS/Fat-induced mice without decoy ODN treatment. These data suggest that NF-κB decoy ODN may exert an inhibitory effect on the expression levels of pro-inflammatory cytokines and cell adhesion molecules in atherosclerotic mice.

Fluorescence kinetics of protoporphyrin-IX induced from 5-ALA compounds in rabbit postballoon injury model for ALA-photoangioplasty.

Protoporphyrin IX (PpIX) is one of the photodynamically active substances that are endogenously synthesized in the metabolic pathway for heme as a precursor. Aminolevulinic acid-esters are more lipophilic than conventional 5-aminolevulinic acid (ALA) and some of them are currently being approved as new drugs for photodynamic diagnosis (PDD) and photodynamic therapy (PDT). In order to investigate the pharmacokinetics of ALA and ALA-ethyl ester (ALA-ethyl) in the atheromatous plaque and normal aortic wall of rabbit postballoon injured artery, each 60 mg kg(-1) of ALA or ALA-ethyl was injected intravenously followed by serial detection of PpIX fluorescence of harvested arteries at 0-48 h post-injection. Maximum PpIX build-up in the atheromatous plaque was seen at 2 h after injecting ALA. In contrast, it occurred at 9 h after injecting ALA-ethyl. In addition, the selective build-up of ALA in the atheromatous plaque compared to normal vessel wall was much higher (10 times) than that of ALA-ethyl. The time of maximum fluorescence intensity of PpIX was employed as drug-light-interval for subsequent PDT treatment of the atheromatous plaque with 50-150 J cm(-1) of light dose. Significant reduction in plaque was observed without damage of the medial wall at both groups, but smooth muscle cell (SMC) was still present in the media region below the PDT-treated atheromatous plaque. In conclusion, ALA may be a more effective compound for endovascular PDT treatment of the atheromatous plaque compared with ALA-ethyl based on their pharmacokinetics, but further optimization of PDT methodology remains to remove completely residual SMC in the media for preventing potential restenosis.