Riesenzellarteriitis : Ätiologische Erkenntnisse und diagnostische Herausforderung für den Pathologen [Giant cell arteritis : Etiological knowledge and diagnostic challenge for pathologists].

Giant cell arteritis is a potentially systemic disease of medium-sized and large caliber arteries, showing a preferential manifestation in the extracranial branches of the carotid artery. The diagnosis is oriented to clinical and histomorphological criteria which will be critically reviewed. Particular emphasis is placed on the differentiation from normal aging processes and from healing stages under steroid therapy. In addition, the advances in our understanding of the disease pathomechanism during the last 10 years will be briefly presented as the basis for the hitherto empiric steroid treatment.

The effect of continuous positive airway pressure on total cerebral blood flow in healthy awake volunteers.

PURPOSE: Continuous positive airway pressure (CPAP) is the gold standard treatment for obstructive sleep apnea. However, the physiologic impact of CPAP on cerebral blood flow (CBF) is not well established. Ultrasound can be used to estimate CBF, but there is no widespread accepted protocol. We studied the physiologic influence of CPAP on CBF using a method integrating arterial diameter and flow velocity (FV) measurements obtained for each vessel supplying blood to the brain. METHODS: FV and lumen diameter of the left and right internal carotid, vertebral, and middle cerebral arteries were measured using duplex Doppler ultrasound with and without CPAP at 15 cm H(2)O, applied in a random order. Transcutaneous carbon dioxide (PtcCO(2)), heart rate (HR), blood pressure (BP), and oxygen saturation were monitored. Results were compared with a theoretical prediction of CBF change based on the effect of partial pressure of carbon dioxide on CBF. RESULTS: Data were obtained from 23 healthy volunteers (mean ± SD; 12 male, age 25.1 ± 2.6 years, body mass index 21.8 ± 2.0 kg/m(2)). The mean experimental and theoretical CBF decrease under CPAP was 12.5 % (p < 0.001) and 11.9 % (p < 0.001), respectively. The difference between experimental and theoretical CBF reduction was not statistically significant (3.84 ± 79 ml/min, p = 0.40). There was a significant reduction in PtcCO(2) with CPAP (p = <0.001) and a significant increase in mean BP (p = 0.0017). No significant change was observed in SaO(2) (p = 0.21) and HR (p = 0.62). CONCLUSION: Duplex Doppler ultrasound measurements of arterial diameter and FV allow for a noninvasive bedside estimation of CBF. CPAP at 15 cm H(2)O significantly decreased CBF in healthy awake volunteers. This effect appeared to be mediated predominately through the hypocapnic vasoconstriction coinciding with PCO(2) level reduction. The results suggest that CPAP should be used cautiously in patients with unstable cerebral hemodynamics.

Secondhand smoke exposure in children is associated with common carotid artery intima-media thickness

Objective: To investigate the association between common carotid artery intima-media thickness (cIMT) and exposure to secondhand smoke (SHS) in children. Methods: Data were available at baseline in the Quebec Adiposity and Lifestyle investigation in Youth (QUALITY) study, an ongoing longitudinal investigation of Caucasian children aged 8e10 years at cohort inception, who had at least one obese parent. Data on exposure to parents, siblings and friends smoking were collected in interviewer-administered child, and self-report parent questionnaires. Blood cotinine was measured with a high sensitivity ELISA. cIMTwas measured by ultrasound. The association between blood cotinine and cIMT was investigated in multivariable linear regression analyses controlling for age, body mass index, and child smoking status. Results: Mean (SD) cIMT (0.5803 (0.04602)) did not differ across age or sex. Overall 26%, 6% and 3% of children were exposed to parents, siblings and friends smoking, respectively. Cotinine ranged from 0.13 ng/ml to 7.38 ng/ml (median (IQR)¼0.18 ng/ml)). Multivariately, a 1 ng/ml increase in cotinine was associated with a 0.090 mm increase in cIMT (p¼0.034). Conclusion: In children as young as age 8e10 years, exposure to SHS relates to cIMT, a marker of pre-clinical atherosclerosis. Given the wide range of health effects of SHS, increased public health efforts are needed to reduced exposure among children in homes an private vehicles.

Effect of selective phosphodiesterase inhibitors on response of ovine pulmonary arteries to prostaglandin E2.

Several adenosine 3',5'-cyclic monophosphate (cAMP)-hydrolyzing phosphodiesterase isozymes are present in the pulmonary vasculature. The present study was designed to determine the effect of selective inhibitors of phosphodiesterase subtypes on prostaglandin E2 (PGE2)-induced relaxation of isolated fourth-generation pulmonary arteries of newborn lambs. PGE2 and forskolin caused pulmonary arteries to relax and induced an increase in the intracellular cAMP content in the vessels. The relaxation and change in cAMP content were augmented by milrinone and rolipram, inhibitors of phosphodiesterase type 3 (PDE3) and type 4 (PDE4), respectively. The augmentation in relaxation and the increase in cAMP content caused by milrinone plus rolipram was greater than the sum of the responses caused by either of the inhibitors alone. 8-Methoxymethyl-1-methyl-3-(2-methylpropyl)xanthine, an inhibitor of phosphodiesterase type 1, had no effect on relaxation and change in cAMP induced by PGE2 and forskolin. Acetylcholine alone had no effect on cAMP content in the vessels but augmented the relaxation and the increase in cAMP induced by PGE2 and forskolin in arteries with endothelium. This effect was not observed in arteries without endothelium or in arteries with endothelium treated with NG-nitro-L-arginine. These results suggest that PDE3 and PDE4 are the primary enzymes hydrolyzing cAMP of pulmonary arteries of newborn lambs and that an inhibition of both PDE3 and PDE4 would result in a greater effect than that caused by inhibition of either one of the subtype isozymes alone. Furthermore, endothelium-derived nitric oxide may enhance cAMP-mediated relaxation by inhibition of PDE3.

How to improve flow during cardiopulmonary bypass in an acardia experimental model.

OBJECTIVES In extreme scenarios, such as hyperacute rejection of heart transplant, an urgent heart explantation might be necessary. The aim of this experimental study was to determine the feasibility and to improve the haemodynamics of a venoarterial cardiopulmonary bypass after cardiectomy. METHODS A venoarterial cardiopulmonary bypass was established in seven calves (56.4 ± 7 kg) by the transjugular insertion to the caval axis of a self-expanding cannula, with a carotid artery return. After baseline measurements (A), ventricular fibrillation was induced (B), great arteries were clamped (C), the heart was excised and the right and left atria remnants, containing the pulmonary veins, were sutured together leaving an atrial septal defect over the cannula in the caval axis (D). Measurements were taken with the pulmonary artery clamped and declamped. RESULTS Initial pump flow was 4.16 ± 0.75 l/min dropping to 2.9 ± 0.63 l/min (P(AB )< 0.001) 10 min after induction of ventricular fibrillation. After cardiectomy with the pulmonary artery clamped, the pump flow increased non-significantly to 3.20 ± 0.78 l/min. After declamping, the flow significantly increased close to baseline levels (3.61 ± 0.73 l/min, P(DB )= 0.009, P(DC )= 0.017), supporting the notion that full cardiopulmonary bypass in acardia is feasible only if adequate drainage of pulmonary circulation is assured to avoid pulmonary congestion and loss of volume from the left-to-right shunt of bronchial vessels.

The "open" chimney graft technique for juxtarenal aortic aneurysms with discrepant renal arteries.

OBJECTIVES: A straightforward original Chimney Graft (CG) protocol has been developed at our institution in selected cases of juxtarenal aortic aneurysm (JRAA). The aim of this study was to present our clinical experience of consecutive series with use of uncovered self-expanding stent (SES) as "Open Chimney" (OCh) in the endovascular repair (EVAR) of JRAA. METHODS: A standard endograft with suprarenal fixation struts is delivered with its proximal covered edge just below the highest RA in JRAA presenting the ostium of the two renal arteries at a different aortic level and the distance between the highest renal artery and the beginning of the aneurysm (improved landing zone) ≥10 mm. The low-lying renal artery is maintained patent by the OCh graft (standard SES) delivered from left brachial access (6 Fr). All clinical, anatomical, and operative data were prospectively collected and retrieved for the study analysis. RESULTS: From July 2010 to November 2012, OCh EVAR was offered to 22 consecutive patients considered unfit for JRAA open repair. All procedures were technically successful with aneurysm exclusion and patent OCh graft. One small perioperative type Ia endoleak spontaneously disappeared at the 3-month CT control. One patient died because of acute decompensated heart failure. One patient presented a left hemispheric stroke. The median follow-up of 18 months (range 7-35) showed aneurysm exclusion in all patients without type I and III endoleaks, SES stenosis, and/or renal impairment. CONCLUSIONS: OCh-EVAR is a straightforward technique that can be employed in selected cases of JRAA, avoiding the more complex and expensive fenestrated EVAR.

CT angiography helps to differentiate acute from chronic carotid occlusion: "carotid ring sign".

INTRODUCTION: Currently, there is no reliable method to differentiate acute from chronic carotid occlusion. We propose a novel CTA-based method to differentiate acute from chronic carotid occlusions that could potentially aid clinical management of patients. METHODS: We examined 72 patients with 89 spontaneously occluded extracranial internal carotids with CT angiography (CTA). All occlusions were confirmed by another imaging modality and classified as acute (imaging <1 week of presumed occlusion) orchronic (imaging >4 weeks), based on circumstantial clinical and radiological evidence. A neuroradiologist and a neurologist blinded to clinical information determined the site of occlusion on axial sections of CTA. They also looked for (a) hypodensity in the carotid artery (thrombus), (b) contrast within the carotid wall (vasa vasorum), (c) the site of the occluded carotid, and (d) the "carotid ring sign" (defined as presence of a and/or b). RESULTS: Of 89 occluded carotids, 24 were excluded because of insufficient circumstantial evidence to determine timing of occlusion, 4 because of insufficient image quality, and 3 because of subacute timing of occlusion. Among the remaining 45 acute and 13 chronic occlusions, inter-rater agreement (kappa) for the site of proximal occlusion was 0.88, 0.45 for distal occlusion, 0.78 for luminal hypodensity, 0.82 for wall contrast, and 0.90 for carotid ring sign. The carotid ring sign had 88.9% sensitivity, 69.2% specificity, and 84.5% accuracy to diagnose acute occlusion. CONCLUSION: The carotid ring sign helps to differentiate acute from chronic carotid occlusion. If further confirmed, this information may be helpful in studying ischemic symptoms and selecting treatment strategies in patients with carotid occlusions.

Prise en charge des sténoses carotidiennes [Management of the carotid artery stenosis].

In the western world, the carotid-artery stenosis is one of the major causes of ischemic stroke in elderly people. The principal therapeutic indication is a symptomatic stenosis > 50% in the first two weeks and the surgical approach has shown the best results. Despite inferior results to carotid endarterectomy in terms of post-operative rate of stroke and/or death, except for young patients, carotid stenting remains the best choice in patients at high surgical risk. The best medical treatment, consisting in correction of cardiovascular risk factors, statin therapy and anti-aggregation led to a drastic reduction in the annual rate of stroke associated to carotid stenosis and thus limited the surgical intervention in asymptomatic patient to men with a life expectancy of at least 5 years and a stenosis > 70%.

Conduit artery compliance and distensibility are not necessarily reduced in hypertension.

The goal of this study was to investigate whether the elastic behavior of conduit arteries of humans or rats is altered as a result of concomitant hypertension. Forearm arterial cross-sectional compliance-pressure curves were determined noninvasively by means of a high precision ultrasonic echo-tracking device coupled to a photoplethysmograph (Finapres system) allowing simultaneous arterial diameter and finger blood pressure monitoring. Seventeen newly diagnosed hypertensive patients with a humeral blood pressure of 163/103 +/- 4.4/2.2 mm Hg (mean +/- SEM) and 17 age- and sex-matched normotensive controls with a humeral blood pressure of 121/77 +/- 3.2/1.9 mm Hg were included in the study. Compliance-pressure curves were also established at the carotid artery of 16-week-old anesthetized spontaneously hypertensive rats (n = 14) as well as Wistar-Kyoto normotensive animals (n = 15) using the same echo-tracking device. In these animals, intra-arterial pressure was monitored in the contralateral carotid artery. Mean blood pressures averaged 197 +/- 4 and 140 +/- 3 mm Hg in the hypertensive and normotensive rats, respectively. Despite the considerable differences in blood pressure, the diameter-pressure and cross-sectional compliance-pressure and distensibility-pressure curves were not different when hypertensive patients or animals were compared with their respective controls. These results suggest that the elastic behavior of a medium size muscular artery (radial) in humans and of an elastic artery (carotid) in rats is not necessarily altered by an increase in blood pressure.

Carotid sparing in t1-t2 no glottic cancer using helical tomotherapy

Objective: To study the dosimetric properties and clinical implementation of a carotid dose sparing irradiation protocol using helical Tomotherapy in early stage laryngeal cancer.Materials and Methods: We have developed a simple treatment planning algorithm for carotid sparing. We have compared carotid and critical organ doses and planned target volume (PTV) dose with our standard laryngeal irradiation protocol. Dose constraints were the following: maximum point dose to the carotids <35 Gy, to the spinal cord <30 Gy, and PTV was covered at >95% of the prescribed dose (70 Gy in 2 Gy per fraction). A daily megavoltage CT was done to account for patient movement and anatomy modification. To date, 7 patients have been treated with this protocol in our department.Results: Our early results showed a significant reduction in the carotid dose with an average maximum dose of 35.8 Gy. The average maximum spinal cord dose was 25.8 Gy. PTV was covered without important "hot spots". Average maximum dose in the PTV was 74.1 Gy with an average absolute maximum dose of 75.2 Gy. To date, the clinical outcomes have been excellent.Conclusion: Helical Tomotherapy allows a significant decrease of carotid dose without dangerous spinal cord overdose. There was no important overdose in the PTV that can potentially increase the late complication risks. Daily control imaging brings added security especially when working with such high-dose gradients. We think further studies and longer follow-up are needed to investigate the clinical outcomes such as the local control rate and the vascular late toxicities.

Biomedical risk assessment as an aid for smoking cessation.

BACKGROUND: A possible strategy for increasing smoking cessation rates could be to provide smokers who have contact with healthcare systems with feedback on the biomedical or potential future effects of smoking, e.g. measurement of exhaled carbon monoxide (CO), lung function, or genetic susceptibility to lung cancer. We reviewed systematically data on smoking cessation rates from controlled trials that used biomedical risk assessment and feedback. OBJECTIVES: To determine the efficacy of biomedical risk assessment provided in addition to various levels of counselling, as a contributing aid to smoking cessation. SEARCH STRATEGY: We systematically searched he Cochrane Collaboration Tobacco Addiction Group Specialized Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (1966 to 2004), and EMBASE (1980 to 2004). We combined methodological terms with terms related to smoking cessation counselling and biomedical measurements. SELECTION CRITERIA: Inclusion criteria were: a randomized controlled trial design; subjects participating in smoking cessation interventions; interventions based on a biomedical test to increase motivation to quit; control groups receiving all other components of intervention; an outcome of smoking cessation rate at least six months after the start of the intervention. DATA COLLECTION AND ANALYSIS: Two assessors independently conducted data extraction on each paper, with disagreements resolved by consensus. MAIN RESULTS: From 4049 retrieved references, we selected 170 for full text assessment. We retained eight trials for data extraction and analysis. One of the eight used CO alone and CO + Genetic Susceptibility as two different intervention groups, giving rise to three possible comparisons. Three of the trials isolated the effect of exhaled CO on smoking cessation rates resulting in the following odds ratios (ORs) and 95% confidence intervals (95% CI): 0.73 (0.38 to 1.39), 0.93 (0.62 to 1.41), and 1.18 (0.84 to 1.64). Combining CO measurement with genetic susceptibility gave an OR of 0.58 (0.29 to 1.19). Exhaled CO measurement and spirometry were used together in three trials, resulting in the following ORs (95% CI): 0.6 (0.25 to 1.46), 2.45 (0.73 to 8.25), and 3.50 (0.88 to 13.92). Spirometry results alone were used in one other trial with an OR of 1.21 (0.60 to 2.42).Two trials used other motivational feedback measures, with an OR of 0.80 (0.39 to 1.65) for genetic susceptibility to lung cancer alone, and 3.15 (1.06 to 9.31) for ultrasonography of carotid and femoral arteries performed in light smokers (average 10 to 12 cigarettes a day). AUTHORS' CONCLUSIONS: Due to the scarcity of evidence of sufficient quality, we can make no definitive statements about the effectiveness of biomedical risk assessment as an aid for smoking cessation. Current evidence of lower quality does not however support the hypothesis that biomedical risk assessment increases smoking cessation in comparison with standard treatment. Only two studies were similar enough in term of recruitment, setting, and intervention to allow pooling of data and meta-analysis.

Redistribution of gastric blood flow by embolization of gastric arteries before esophagectomy.

Background. Anastomotic leak remains a common and potentially deleterious complication after esophagectomy. Preoperative embolization of the left gastric artery and splenic artery (PAE) has been suggested to lower anastomotic leak rates. We present the results of our 5-year experience with this technique.Methods. All patients undergoing PAE before esophagectomy since introduction of this technique in 2004 were compared in a 1: 2 matched-pair analysis with patients without PAE. Matching criteria were type of anastomosis, neoadjuvant treatment, comorbidity, and age. Data were derived from a retrospective chart review from 2000 to 2006 that was perpetuated as a prospective database up to date. Outcome measures were anastomotic leak, overall complications, and hospital stay.Results. Between 2000 and 2009, 102 patients underwent esophagectomy for cancer in our institution with an overall leak rate of 19% and a mortality of 8%. All 19 patients having PAE since 2004 were successfully matched 1: 2 to 38 control patients without PAE; both groups were similar regarding demographics and operation characteristics. Two PAE (11%) and 8 control patients (21%) had an anastomotic leak, but the difference was statistically not significant (p = 0.469). Overall and major complication rates for PAE and control group were 89% versus 79% (p = 0.469) and 37% versus 34% (p = 1.000), respectively. Median intensive care unit and hospital stay were 3 versus 3 days (p = 1.000) and 22 versus 17 days (p = 0.321), respectively.Conclusions. In our experience, PAE has no significant impact on complications and anastomotic leak in particular after esophagectomy. (Ann Thorac Surg 2011;91:1556-61) (C) 2011 by The Society of Thoracic Surgeons