967 resultados para mesenteric artery


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BACKGROUND: Despite recent advances in acute stroke treatment, basilar artery occlusion (BAO) is associated with a death or disability rate of close to 70%. Randomised trials have shown the safety and efficacy of intravenous thrombolysis (IVT) given within 4.5 h and have shown promising results of intra-arterial thrombolysis given within 6 h of symptom onset of acute ischaemic stroke, but these results do not directly apply to patients with an acute BAO because only few, if any, of these patients were included in randomised acute stroke trials.Recently the results of the Basilar Artery International Cooperation Study (BASICS), a prospective registry of patients with acute symptomatic BAO challenged the often-held assumption that intra-arterial treatment (IAT) is superior to IVT. Our observations in the BASICS registry underscore that we continue to lack a proven treatment modality for patients with an acute BAO and that current clinical practice varies widely. DESIGN: BASICS is a randomised controlled, multicentre, open label, phase III intervention trial with blinded outcome assessment, investigating the efficacy and safety of additional IAT after IVT in patients with BAO. The trial targets to include 750 patients, aged 18 to 85 years, with CT angiography or MR angiography confirmed BAO treated with IVT. Patients will be randomised between additional IAT followed by optimal medical care versus optimal medical care alone. IVT has to be initiated within 4.5 h from estimated time of BAO and IAT within 6 h. The primary outcome parameter will be favourable outcome at day 90 defined as a modified Rankin Scale score of 0-3. DISCUSSION: The BASICS registry was observational and has all the limitations of a non-randomised study. As the IAT approach becomes increasingly available and frequently utilised an adequately powered randomised controlled phase III trial investigating the added value of this therapy in patients with an acute symptomatic BAO is needed (clinicaltrials.gov: NCT01717755).

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Purpose: To analyse prospectively the long-term results of Gamma Knife surgery (GKS) in patients with trigeminal neuralgia secondary to megadolichobasilar artery (MBA). Methods: Between December 1992 and November 2010, 33 consecutive patients presenting with ITN secondary to MBA were operated by GKS and followed prospectively in Timone University Hospital. The follow up is at least of 1 year in 29 patients. The median age was 74.90 years (range 51 to 90). The GKS typically was performed using MR and CT imaging guidance and a single 4 mm isocenter. The median of the prescription dose (at the 100%) was 90 Gy (range 80 to 90). The target was placed on the cisternal portion of the Vth nerve. Clinical and dosimetric parameters were analyzed. GKS was the first surgical procedure in 23 patients (79.31%). Results: The median follow- up period was 46.12 months (range 12.95 to 157.93). All the 29 patients (100%) were initially pain free in a median time of 13.5 days (range 0 to 240). The probability of remaining pain free at 0.5, 1, 2 years was 93.1%, 79.3% and 75.7% respectively, reaching at this time the flat part of the curve. Seven patients (24.13%) experienced a recurrence with a median delay of 10.75 months (range 3.77 to 12.62). The actuarial rate of recurrence was not higher than in our population with essential TN although atypical pain was associated with a much higher risk of recurrence (HR= 6.92, p= 0.0117). The hypoesthesia actuarial rates at 0.5 years was 4.3% and at 1 year reach 13% and remains stable till 12 years with a median delay of onset of 7 (5, 12) months. Female patients had a statistically much lower probability of developing a facial numbness (p of 0.03). No patient reported a bothersome hypoesthesia. Conclusion: Retrogaserian, high dose GKS, turned out to be very safe with only 13.04% hypoesthesia, which was never disabling (0%), while achieving high quality pain control. The majority of the patients demonstrated a prolonged effect of radiosurgery in absence of any trigeminal nerve disturbance.

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BACKGROUND: Treatment strategies for acute basilar artery occlusion (BAO) are based on case series and data that have been extrapolated from stroke intervention trials in other cerebrovascular territories, and information on the efficacy of different treatments in unselected patients with BAO is scarce. We therefore assessed outcomes and differences in treatment response after BAO. METHODS: The Basilar Artery International Cooperation Study (BASICS) is a prospective, observational registry of consecutive patients who presented with an acute symptomatic and radiologically confirmed BAO between November 1, 2002, and October 1, 2007. Stroke severity at time of treatment was dichotomised as severe (coma, locked-in state, or tetraplegia) or mild to moderate (any deficit that was less than severe). Outcome was assessed at 1 month. Poor outcome was defined as a modified Rankin scale score of 4 or 5, or death. Patients were divided into three groups according to the treatment they received: antithrombotic treatment only (AT), which comprised antiplatelet drugs or systemic anticoagulation; primary intravenous thrombolysis (IVT), including subsequent intra-arterial thrombolysis; or intra-arterial therapy (IAT), which comprised thrombolysis, mechanical thrombectomy, stenting, or a combination of these approaches. Risk ratios (RR) for treatment effects were adjusted for age, the severity of neurological deficits at the time of treatment, time to treatment, prodromal minor stroke, location of the occlusion, and diabetes. FINDINGS: 619 patients were entered in the registry. 27 patients were excluded from the analyses because they did not receive AT, IVT, or IAT, and all had a poor outcome. Of the 592 patients who were analysed, 183 were treated with only AT, 121 with IVT, and 288 with IAT. Overall, 402 (68%) of the analysed patients had a poor outcome. No statistically significant superiority was found for any treatment strategy. Compared with outcome after AT, patients with a mild-to-moderate deficit (n=245) had about the same risk of poor outcome after IVT (adjusted RR 0.94, 95% CI 0.60-1.45) or after IAT (adjusted RR 1.29, 0.97-1.72) but had a worse outcome after IAT compared with IVT (adjusted RR 1.49, 1.00-2.23). Compared with AT, patients with a severe deficit (n=347) had a lower risk of poor outcome after IVT (adjusted RR 0.88, 0.76-1.01) or IAT (adjusted RR 0.94, 0.86-1.02), whereas outcomes were similar after treatment with IAT or IVT (adjusted RR 1.06, 0.91-1.22). INTERPRETATION: Most patients in the BASICS registry received IAT. Our results do not support unequivocal superiority of IAT over IVT, and the efficacy of IAT versus IVT in patients with an acute BAO needs to be assessed in a randomised controlled trial. FUNDING: Department of Neurology, University Medical Center Utrecht.

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The acute effects of various vasopressor agents on the diameter of the common carotid artery were studied in halothane-anesthetized normotensive rats. The animals were infused intravenously for 60 min with equipressor doses of angiotensin II (10 ng/min), the alpha1-stimulant methoxamine (5 microg/min), lysine vasopressin (5 mU/min), or vehicle. The arterial diameter was measured by using a high-resolution ultrasonic echo-tracking device. The three vasoconstrictors increased the carotid artery diameter, but this effect was significantly more pronounced with lysine vasopressin. Even a nonpressor dose of lysine vasopressin (1 mU/min) caused a significant increase in the arterial diameter. The lysine vasopressin-induced vasodilatation could be prevented by the administration of d(CH2)5Tyr(Me)AVP (10 microg, i.v.), a selective V1-vasopressinergic receptor antagonist. These data therefore suggest that a short-term increase in blood pressure induces in rats a distention of the carotid artery. The increase in arterial diameter seems to involve an active mechanism with lysine vasopressin caused by the stimulation of V1-vasopressinergic receptors.

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Introduction: According to guidelines, patients with coronary artery disease (CAD) should undergo revascularization if myocardial ischemia is present. While coronary angiography (CXA) allows the morphological assessment of CAD, the fractional flow reserve (FFR) has proved to be a complementary invasive test to assess the functional significance of CAD, i.e. to detect ischemia. Perfusion Cardiac Magnetic Resonance (CMR) has turned out to be a robust non-invasive technique to assess myocardial ischemia. The objective: is to compare the cost-effectiveness ratio - defined as the costs per patient correctly diagnosed - of two algorithms used to diagnose hemodynamically significant CAD in relation to the pretest likelihood of CAD: 1) aCMRto assess ischemia before referring positive patients to CXA (CMR + CXA), 2) a CXA in all patients combined with a FFR test in patients with angiographically positive stenoses (CXA + FFR). Methods: The costs, evaluated from the health care system perspective in the Swiss, German, the United Kingdom (UK) and the United States (US) contexts, included public prices of the different tests considered as outpatient procedures, complications' costs and costs induced by diagnosis errors (false negative). The effectiveness criterion wasthe ability to accurately identify apatient with significantCAD.Test performancesused in the model were based on the clinical literature. Using a mathematical model, we compared the cost-effectiveness ratio for both algorithms for hypothetical patient cohorts with different pretest likelihood of CAD. Results: The cost-effectiveness ratio decreased hyperbolically with increasing pretest likelihood of CAD for both strategies. CMR + CXA and CXA + FFR were equally costeffective at a pretest likelihood of CAD of 62% in Switzerland, 67% in Germany, 83% in the UK and 84% in the US with costs of CHF 5'794, Euros 1'472, £ 2'685 and $ 2'126 per patient correctly diagnosed. Below these thresholds, CMR + CXA showed lower costs per patient correctly diagnosed than CXA + FFR. Implications for the health care system/professionals/patients/society These results facilitate decision making for the clinical use of new generations of imaging procedures to detect ischemia. They show to what extent the cost-effectiveness to diagnose CAD depends on the prevalence of the disease.

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Triglycerides are transported in plasma by specific triglyceride-rich lipoproteins; in epidemiological studies, increased triglyceride levels correlate with higher risk for coronary artery disease (CAD). However, it is unclear whether this association reflects causal processes. We used 185 common variants recently mapped for plasma lipids (P < 5 × 10(-8) for each) to examine the role of triglycerides in risk for CAD. First, we highlight loci associated with both low-density lipoprotein cholesterol (LDL-C) and triglyceride levels, and we show that the direction and magnitude of the associations with both traits are factors in determining CAD risk. Second, we consider loci with only a strong association with triglycerides and show that these loci are also associated with CAD. Finally, in a model accounting for effects on LDL-C and/or high-density lipoprotein cholesterol (HDL-C) levels, the strength of a polymorphism's effect on triglyceride levels is correlated with the magnitude of its effect on CAD risk. These results suggest that triglyceride-rich lipoproteins causally influence risk for CAD.

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BACKGROUND: Temporal arteritis is a very serious form of vasculitis. Early treatment is essential to avoid blindness. Surgical biopsy of the temporal artery is the gold standard for the diagnosis, but facial nerve injuries may occur. OBJECTIVE: To describe a simple and safe procedure for temporal artery biopsy. METHODS: Case report. RESULTS: A 62-year-old-woman with presumed temporal arteritis was referred. Precise localization of temporal arteries and its branches was obtained with color duplex ultrasonography. Arterial wall thickening (halo sign) was observed in the affected arterial segments. A frontal branch was precisely localized and infiltrated with 1% lidocaine. About 1 cm was removed for histopathologic examination. Thirty minutes was required to perform this outpatient procedure. The diagnosis of temporal arteritis was confirmed, and the patient was rapidly and successfully treated with prednisone. CONCLUSIONS: Color duplex ultrasonography allows precise localization of temporal arteries and its branches. This echocardiography-guided surgical procedure is easy and safe. Most dermatologic surgeons can perform it.

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In endoscopic sinus surgery, knowledge of the course of the internal ethmoida and orbital arteries is crucial.The maxillary and the internal carotid arteries of cadavers were injected with radio-opaque , red colorede silicone. The ethmoidal regions were perpared and plastinated using the standard S10 technique. On some specimens, the ophtalmic and ethmoidal arteries were dissected prior to plastination. The plastinated specimens of the ethmoidal blocks were successfullyintroduced into clinical teaching of sinus anatomy and surgery as an aid to study vaascularization an dits relationship to surgical procedures. Among the advantages of this method are the long-lasting preservation of dissected tissue, visualization of arteries during endoscopic and radiological examinations, and invaluable teachjing and training resources for endoscopic sinus surgery.

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OBJECTIVES: This study was designed to assess the prevalence of major cardiovascular risk factors in familial premature coronary artery disease (P-CAD), affecting two or more siblings within one sibship. BACKGROUND: Premature CAD has a genetic component. It remains to be established whether familial P-CAD is due to genes acting independently from major cardiovascular risk factors. METHODS: We recruited 213 P-CAD survivors from 103 sibships diagnosed before age <or=50 (men) or <or=55 (women) years old. Hypertension, hypercholesterolemia, obesity, and smoking were documented at the time of the event in 163 patients (145 men and 18 women). Each patient was compared with two individuals of the same age and gender, diagnosed with sporadic (nonfamilial) P-CAD, and three individuals randomly sampled from the general population. RESULTS: Compared with the general population, patients with sporadic P-CAD had a higher prevalence of hypertension (29% vs. 14%, p < 0.001), hypercholesterolemia (54% vs. 33%, p < 0.001), obesity (20% vs. 13%, p < 0.01), and smoking (76% vs. 39%, p < 0.001). These risk factors were equally or even more prevalent in patients with familial P-CAD (43% [p < 0.05 vs. sporadic P-CAD], 58% [p = 0.07], 21% and 72%, respectively). Overall, only 7 (4%) of 163 of patients with familial P-CAD and 22 (7%) of 326 of patients with sporadic P-CAD had none of these conditions, as compared with 167 (34%) of 489 patients in the general population. CONCLUSIONS: Classic, remediable risk factors are highly prevalent in patients with familial P-CAD. Accordingly, a major contribution of genes acting in the absence of these risk factors is unlikely.

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PURPOSE: To evaluate accuracy and reproducibility of flow velocity and volume measurements in a phantom and in human coronary arteries using breathhold velocity-encoded (VE) MRI with spiral k-space sampling at 3 Tesla. MATERIALS AND METHODS: Flow velocity assessment was performed using VE MRI with spiral k-space sampling. Accuracy of VE MRI was tested in vitro at five constant flow rates. Reproducibility was investigated in 19 healthy subjects (mean age 25.4 +/- 1.2 years, 11 men) by repeated acquisition in the right coronary artery (RCA). RESULTS: MRI-measured flow rates correlated strongly with volumetric collection (Pearson correlation r = 0.99; P < 0.01). Due to limited sample resolution, VE MRI overestimated the flow rate by 47% on average when nonconstricted region-of-interest segmentation was used. Using constricted region-of-interest segmentation with lumen size equal to ground-truth luminal size, less than 13% error in flow rate was found. In vivo RCA flow velocity assessment was successful in 82% of the applied studies. High interscan, intra- and inter-observer agreement was found for almost all indices describing coronary flow velocity. Reproducibility for repeated acquisitions varied by less than 16% for peak velocity values and by less than 24% for flow volumes. CONCLUSION: 3T breathhold VE MRI with spiral k-space sampling enables accurate and reproducible assessment of RCA flow velocity.

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We describe a simple method to achieve both hemostasis and stabilization of the left anterior descending coronary artery during minimally invasive coronary artery bypass grafting. This technique allows the surgeon to perform a precise anastomosis of the left internal mammary artery to the target vessel on a beating heart.

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Instead of standard rigid thoracoscopes, we used a modified gastroscope for video assistance during 12 minimally invasive left internal mammary harvesting. Flexibility and remote control of its last centimeters give to the gastroscope a total freedom of movements, and perfect positioning in every direction. The scope is equipped with cold light, a suction canal and an irrigation canal, which allow for in situ washing without needing to remove it from the thoracic cavity. Thanks to these advantages, vision and lighting are always perfect.

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OBJECTIVES: The goal was to test 2 hypotheses: first, that coronary endothelial function can be measured noninvasively and abnormal function detected using clinical 3.0-T magnetic resonance imaging (MRI); and second, that the extent of local coronary artery disease (CAD), in a given patient, is related to the degree of local abnormal coronary endothelial function. BACKGROUND: Abnormal endothelial function mediates the initiation and progression of atherosclerosis and predicts cardiovascular events. However, direct measures of coronary endothelial function have required invasive assessment. METHODS: The MRI was performed in 20 healthy adults and 17 patients with CAD. Cross-sectional coronary area and blood flow were quantified before and during isometric handgrip exercise, an endothelial-dependent stressor. In 10 severe, single-vessel CAD patients, paired endothelial function was measured in the artery with severe stenosis and the contralateral artery with minimal disease. RESULTS: In healthy adults, coronary arteries dilated and flow increased with stress. In CAD patients, coronary artery area and blood flow decreased with stress (both p </= 0.02). In the paired study, coronary artery area and blood flow failed to increase during exercise in the mildly diseased vessel, but both area (p = 0.01) and blood flow (p = 0.02) decreased significantly in the severely diseased, contralateral artery. CONCLUSIONS: Endothelial-dependent coronary artery dilation and increased blood flow in healthy subjects, and their absence in CAD patients, can now be directly visualized and quantified noninvasively. Local coronary endothelial function differs between severely and mildly diseased arteries in a given CAD patient. This novel, safe method may offer new insights regarding the importance of local coronary endothelial function and improved risk stratification in patients at risk for and with known CAD.