Infrared imaging of subcutaneous veins Zharov, Vladimir P.; Ferguson, Scott; Eidt, John F. ...
Lasers in surgery and medicine,
01/2004, Letnik:
34, Številka:
1
Journal Article
Purpose: This preliminary study investigated the ability to elevate the serum homocysteine (He) levels and investigated the increases in postoperative neointimal hyperplasia (IH) in an environment ...with hyperhomocysteinemia and the resultant restenosis in a rat carotid endarterectomy (CEA) model.
Method: The 9 rats for the control group were fed rat chow, and the 8 rats for the H(e) group were fed H(e)-supplemented rat chow for 2 weeks before and after CEA. The animals underwent anesthesia, and a left common CEA was performed. After 14 days, the serum H(e) levels were measured and the left carotid artery was harvested and elastin stained. Morphometric measurements were used to calculate the area of stenosis of the lumen. The mean and the standard deviation of the mean were determined. The 2 groups were compared with the Mann-Whitney test and a linear regression model. Three additional rats per group were studied, with carotid artery sectioning with double immunohistochemical staining for 5-bromodeoxyuridine (BrdU) and α–smooth muscle (α-SM) actin.
Results: The serum H(e) level in the H(e) group was 36.32 μmol/L ± 15.28, and in the control group the level was 5.53 μmol/L ± 2.06 (
P = .0007). IH presented as percent lumen stenosis was 21.89% ± 4.82% in the H(e) group and 4.82% ± 1.64% in the control group (
P = .0007). The linear regression model of the serum H(e) levels and the percent stenosis showed a linear relationship (
r
2 = .72). The α-SM actin staining revealed that nearly all of the cells in the IH area were of smooth muscle or myofibroblast origin and that 10.1% ± 2.6% of the cells were stained for BrdU in the control group versus 23% ± 7.1% in the H(e) group. Also, 9.3% ± 2.6% of the cells in the IH area were stained for BrdU and for α-SM actin versus 19.1% ± 5.6% stained for both BrdU and α-SM actin in the H(e) group.
Conclusion: This is the first study to examine IH after CEA and hyperhomocysteinemia in rats. The study shows that the elevation of serum H(e) levels can be obtained by feeding rats modified diets with added H(e). The consistent elevation of serum H(e) levels was associated with more than 4 times the amount of IH after a CEA in a rat model. (J Vasc Surg 1998;28:909-18.)
We have speculated previously that the abrupt conversion from chronic stable to unstable angina and the continuum to acute myocardial infarction may result from myocardial ischemia caused by ...progressive platelet aggregation and dynamic vasoconstriction themselves caused by local increases in thromboxane and serotonin at sites of coronary artery stenosis and endothelial injury. Platelet aggregation and dynamic coronary artery vasoconstriction probably result from the local accumulation of thromboxane and serotonin and also relative decreases in the local concentrations of endothelially derived vasodilators and inhibitors of platelet aggregation, such as endothelium-derived relaxing factor (EDRF) and prostacyclin. With severe reductions in coronary blood flow caused by these mechanisms, platelet aggregates may increase, and an occlusive thrombus composed of platelets and white and red blood cells in a fibrin mesh may develop. When coronary arteries are occluded or narrowed for a sufficient period of time by these mechanisms, myocardial necrosis, electrical instability, or sudden death may occur. We believe that unstable angina and acute myocardial infarction are a continuum in relation to the process of coronary artery thrombosis and vasoconstriction. When the period of platelet aggregation or dynamic vasoconstriction at sites of endothelial injury and coronary artery stenosis is brief, unstable angina or non-Q wave infarction may occur. However, when the coronary artery obstruction by these mechanisms is prolonged for several hours, Q wave myocardial infarction results. Chronic endothelial injury and coronary artery stenosis are probably associated with the accumulation of platelets, white and red blood cells, and a fibrin mesh at the site of stenosis and endothelial injury.
Background: For securing immediate hemostasis following percutaneous arterial catheterization, the Food and Drug Administration has approved three hemostatic puncture closure devices. We reviewed our ...institutional experience with one device (Angio-Seal).
Methods: A retrospective, single-center, nonrandomized observational study was made of all vascular complications following femoral cardiac catheterization.
Results: An immediate mechanical failure of the device was experienced in 34 (8%) patients. Surgical repair was required in 1.6% (7 of 425) of patients following Angio-Seal versus 0.3% (5 of 1662) following routine manual compression (P = 0.004). In 5 patients, the device caused either complete occlusion or stenosis of the femoral artery. The polymer anchor embolized in 1 patient and was retrieved with a balloon catheter at surgery.
Conclusion: During the first year of utilization of a percutaneous hemostatic closure device following cardiac catheterization, we observed a marked increase in arterial occlusive complications requiring surgical repair. Surgeons must be familiar with the design of these devices to achieve precise repair of surgical complications.
Cyclic variations in coronary blood flow (CFVs) in dogs with experimental coronary artery stenosis and endothelial injury appear to result primarily from the aggregation of platelets at the site of ...stenosis followed by dislodgement and distal embolization. Using this canine model, we tested the hypotheses: (a) that thrombin is an important mediator of CFVs in dogs with coronary stenoses and endothelial injury; (b) that inhibition of thrombin with heparin, or MCI-9038, a selective thrombin inhibitor, abolishes CFVs in this model; and (c) that abolition of CFVs by thrombin inhibition is time dependent. CFVs, produced in open-chest dogs by placing a flow-reducing plastic constrictor around the left anterior coronary artery, were monitored for either 30 min (group I) or 3 h (group II) before treatment with either heparin or 4-methyl-1-(N2-(3-methyl-1,2,3,4-tetrahydro-8-quinolinyl (MCI-9038). In group I, cyclic flow variations were abolished by heparin in 12 of 18 dogs and by MCI-9038 in 5 of 7 dogs. In group II, cyclic flow variations were not abolished by heparin in any of seven dogs and were abolished by MCI-9038 in only one of seven dogs. Thus, (a) thrombin appears to be an important mediator of cyclic flow variations in dogs with coronary artery stenosis and endothelial injury and (b) inhibition of thrombin abolishes CFVs after short but not prolonged periods of CFVs.
Purpose: This multicenter, randomized, double-blinded, active sham-controlled pivotal study was designed to assess the efficacy and safety of high-frequency nerve block treatment for chronic ...post-amputation and phantom limb pain. Patients and Methods: QUEST enrolled 180 unilateral lower-limb amputees with severe post-amputation pain, 170 of whom were implanted with the Altius device, were randomized 1:1 to active-sham or treatment groups and reached the primary endpoint. Responders were those subjects who received greater than or equal to50% pain relief 30 min after treatment in greater than or equal to50% of their self-initiated treatment sessions within the 3-month randomized period. Differences between the active treatment and sham control groups as well as numerous secondary outcomes were determined. Results: At 30-min, (primary outcome), 24.7% of the treatment group were responders compared to 7.1% of the control group (p=0.002). At 120-minutes following treatment, responder rates were 46.8% in the Treatment group and 22.2% in the Control group (p=0.001). Improvement in Brief Pain Inventory interference score of 2.3 + or - 0.29 was significantly greater in treatment group than the 1.3 + or - 0.26-point change in the Control group (p = 0.01). Opioid usage, although not significantly different, trended towards a greater reduction in the treatment group than in the control group. The incidence of adverse events did not differ significantly between the treatment and control groups. Conclusion: The primary outcomes of the study were met, and the majority of Treatment patients experienced a substantial improvement in PAP (regardless of meeting the study definition of a responder). The significant in PAP was associated with significantly improved QOL metrics, and a trend towards reduced opioid utilization compared to Control. These data indicate that Altius treatment represents a significant therapeutic advancement for lower-limb amputees suffering from chronic PAP. Keywords: post-amputation pain, phantom limb pain, neuromodulation, peripheral nerve stimulation, high-frequency nerve block
Background: Femoral access site complications have increased as the fields of invasive cardiology, radiology, and endovascular surgery have emerged. In order to address one of these complications, ...hemorrhage, the hemostatic puncture closure devices were developed.
Methods: Retrospective review of cardiac catheterizations performed at a single institution to investigate infectious groin complications related to use of the Perclose Prostar and Techstar devices.
Results: Infectious groin complications were significantly higher in the Perclose group as compared with manual compression. Three patients had clinical and laboratory evidence of arterial infection whereas 2 had soft tissue infections. All 5 required operative intervention ranging from incision and drainage to arterial reconstruction. Hemorrhagic complications were not significantly different between the two groups.
Conclusions: The Perclose devices provide hemostasis after femoral artery catheterization similar to manual compression. However, infectious groin complications appear to be more common with these devices.
To determine if intra-arterial stent placement can adequately treat lesions producing microemboli to the lower extremities.
During a 6.5-year period, 15 patients presenting with blue toe syndrome had ...16 presumed embolic lesions treated with intra-arterial stents. These patients were evaluated during routine clinical follow-up during a 6-month period. This evaluation included physical and noninvasive arterial examinations. When patients could not return for follow-up, hospital, clinical, vascular laboratory, and radiology records were reviewed to assemble the appropriate information. Outcomes included symptoms of recurrent emboli, amputation, and death.
Treated embolic lesions included two aortic stenoses, three bilateral iliac artery stenoses, nine unilateral iliac artery stenoses (one patient received separate treatment of unilateral iliac lesions), and two superficial femoral artery stenoses. Patients were followed-up for a mean of 18 months. Eight of 15 patients (53%) were improved or stable without complications. There were eight negative outcomes experienced in seven patients. Three patients (20%) were deceased at follow-up. Four patients (27%) had undergone amputation; one transmetatarsal amputation and three below-the-knee amputations. Only one of these was related to progressive disease in the treated extremity (7%). One patient (7%) experienced recurrent embolic symptoms. Stents were patent in all patients.
Patients with blue toe syndrome are at high risk of limb loss and mortality despite treatment. Intra-arterial stent placement provides an alternative to standard surgical treatment. Further studies are needed to define the optimum therapy.
A 74-year old woman sought medical attention for general symptoms of nausea, vomiting, and back pain. A computed tomographic scan showed gas in the wall of the descending thoracic and suprarenal ...aortas. Emergency thoracoabdominal exploration revealed a necrotizing infection of the thoracic aorta extending to the origin of the celiac axis. After surgery Clostridium septicum was identified in tissue culture. Surgical management consisted of in-situ graft replacement of the thoracoabdominal aorta. Three months later, a pseudoaneurysm developed at the distal anastomosis. The patient refused further surgery and died 3 days later. The cause of death was presumed to be a ruptured mycotic aneurysm as a result of recurrent C. septicum infection. The relationship of C. septicum with occult gastrointestinal and hematologic malignancy has been documented. This patient represents the 10th reported case of C. septicum arteritis. Including the nine previous case reports of C. septicum arteritis, the mortality rate is 70%. When evaluating a patient with a mycotic aneurysm or aortitis, C. septicum should be considered. If it is found, a search should be carried out for an associated gastrointestinal or hematologic malignancy. Surgical repair should include extraanatomic revascularization and wide debridement of the infected field. Consideration should be given to lifelong antimicrobial therapy for this potentially fatal infection.
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