Donitriptan, but not sumatriptan, inhibits capsaicin-induced canine external carotid vasodilatation via 5-HT1B rather than 5-HT1D receptors.
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BACKGROUND AND PURPOSE: It has been suggested that during a migraine attack capsaicin-sensitive trigeminal sensory nerves release calcitonin gene-related peptide (CGRP), resulting in cranial vasodilatation and central nociception; hence, trigeminal inhibition may prevent this vasodilatation and abort migraine headache. This study investigated the effects of the agonists sumatriptan (5-HT(1B/1D) water-soluble), donitriptan (5-HT(1B/1D) lipid-soluble), PNU-142633 (5-HT(1D) water-soluble) and PNU-109291 (5-HT(1D) lipid-soluble) on vasodilator responses to capsaicin, alpha-CGRP and acetylcholine in dog external carotid artery. EXPERIMENTAL APPROACH: 59 vagosympathectomized dogs were anaesthetized with sodium pentobarbitone. Blood pressure and heart rate were recorded with a pressure transducer, connected to a cannula inserted into a femoral artery. A precalibrated flow probe was placed around the common carotid artery, with ligation of the internal carotid and occipital branches, and connected to an ultrasonic flowmeter. The thyroid artery was cannulated for infusion of agonists. KEY RESULTS: Intracarotid infusions of capsaicin, alpha-CGRP and acetylcholine dose-dependently increased blood flow through the carotid artery. These responses remained unaffected after intravenous (i.v.) infusions of sumatriptan, PNU-142633, PNU-109291 or physiological saline; in contrast, donitriptan significantly attenuated the vasodilator responses to capsaicin, but not those to alpha-CGRP or acetylcholine. Only sumatriptan and donitriptan dose-dependently decreased the carotid blood flow. Interestingly, i.v. administration of the antagonist, SB224289 (5-HT(1B)), but not of BRL15572 (5-HT(1D)), abolished the inhibition by donitriptan. CONCLUSIONS AND IMPLICATIONS: Our results suggest that the inhibition produced by donitriptan of capsaicin-induced external carotid vasodilatation is mainly mediated by 5-HT(1B), rather than 5-HT(1D), receptors, probably by a central mechanism. (+info)
Increased prevalence of subclinical atherosclerosis in patients with small-vessel vasculitis.
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BACKGROUND AND OBJECTIVE: Although changes in smaller vessels is the hallmark of medium-sized and small-vessel vasculitis, it has been suggested that large arteries of such patients may also be affected by the early atherosclerotic process because of coexisting risk factors or systemic inflammation. This study aimed to bring additional arguments supporting this hypothesis. DESIGN, SETTING AND PATIENTS: 50 consecutive patients with primary systemic necrotising vasculitis and 100 controls matched for age and sex underwent ultrasonic detection of plaque in three peripheral vessels (carotid and femoral arteries and abdominal aorta). Cardiovascular risk factors and inflammation (C reactive protein (CRP)) were concomitantly measured in all participants, and diagnosis of high-risk status was defined by the presence of known history of cardiovascular disease, type 2 diabetes or 10-year-Framingham Risk Score > or =20%. RESULTS: Patients had higher frequency of plaque than controls in the carotid arteries (p<0.05), in the aorta (p<0.01) and in the three vessels examined (p<0.001), and adjustment for high-risk status did not confound such difference in the aorta and in the three vessels. In the overall population of patients and controls, vasculitis was associated with a higher frequency of three-vessel plaques (p<0.05), independently of high-risk status and CRP. In patients, the higher frequency of three-vessel plaques was associated with high-risk status (p<0.05) but not with CRP, or disease and treatment characteristics. CONCLUSIONS: Small-vessel vasculitis is associated with more frequent subclinical atherosclerosis, especially extended to multiple peripheral vessels, and such association is not entirely explained by cardiovascular risk factors and systemic inflammation. (+info)
Combined open and endovascular treatment of a saccular aneurysm and redundant loop of the internal carotid artery.
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We report the unusual case of a woman with a saccular aneurysm of the distal cervical internal carotid artery arising just distal to a kink and a 360 degrees redundant loop. The retromandibular position of the aneurysm would have mandated a complex surgical procedure. A purely endovascular approach was not possible owing to the difficulty to pass any kind of device beyond the redundant loop. A hybrid approach, in which the kink was surgically straightened and the saccular aneurysm coiled after stenting of its orifice, was therefore used to treat this challenging case. A review of the literature supporting this approach is discussed. (+info)
Safety, feasibility, and short-term follow-up of drug-eluting stent placement in the intracranial and extracranial circulation.
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BACKGROUND AND PURPOSE: The use of bare metal stents to treat symptomatic intracranial stenosis may be associated with significant restenosis rates. The advent of drug-eluting stents (DESs) in the coronary circulation has resulted in a reduction of restenosis rates. We report our technical success rate and short-term restenosis rates after stenting with DESs in the intracranial and extracranial circulation. METHODS: This study was a retrospective review of the period between April 1, 2004, and April 15, 2006, of 59 patients with 62 symptomatic intracranial or extracranial atherosclerotic lesions at 2 medical centers (University of Pittsburgh and Borgess Medical Center). RESULTS: The mean age of our cohort was 61+/-12 years. The location of the 62 lesions was as follows: extracranial vertebral artery 31 (50%), intracranial vertebral artery or basilar artery 18 (29%), extracranial internal carotid artery (ICA) near the petrous bone 5 (8%), and intracranial ICA 8 (13%). There were 2 (3%) periprocedural complications: 1 non-flow-limiting dissection and 1 disabling stroke. Fifty vessels were available for follow-up angiography or computed tomography angiography at a median time of 4.0+/-2 months. A total of 2 of 36 extracranial stents (7%) and 1 of 26 intracranial stents (5%) were found to have restenosis > or = 50% at follow-up. CONCLUSIONS: This report demonstrates that DES delivery in the intracranial and extracranial circulation is technically feasible. A small percentage of patients developed short-term in-stent restenosis. Longer-term follow-up is required in the setting of a prospective study to determine the late restenosis rates for DESs in comparison with bare metal stents. (+info)
Anterior ethmoidal artery aneurysm and intracerebral hemorrhage.
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The association between the formation of intracranial aneurysms and situations of increased blood flow in certain areas of the brain is well accepted today. It has been seen in association with arteriovenous malformations of the brain, carotid occlusion, and Moyamoya disease. The occurrence of aneurysms in small arteries of the skull base, with the exception of the intracavernous carotid artery, however, is rare. We report a case of a 55-year-old woman who presented with an intracerebral hemorrhage caused by a ruptured anterior ethmoidal artery aneurysm. To the best of our knowledge, this is only the second case of documented intracranial bleeding from such a lesion. (+info)
Carotid-compression technique for the insertion of guiding catheters.
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Inserting a guiding catheter into a tortuous artery for neurointerventional procedures can be difficult. In our technique, the carotid artery is manually compressed to stabilize and/or straighten the inserted wire before advancing the guiding catheter. Although this technique is not risk-free and care must be taken to avoid vascular injury by excessive compression, it is useful for the insertion of a guiding catheter into the carotid artery. (+info)
Carotid artery plaque thickness is associated with increased serum calcium levels: the Northern Manhattan study.
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BACKGROUND: Elevated serum calcium concentrations are associated with vascular calcification and cardiovascular disease. It is unknown whether there is a relationship between high-normal serum calcium levels and sub-clinical vascular effects. We investigated the association between serum calcium and carotid plaque thickness, a powerful early predictor of clinical coronary and cerebrovascular events. METHODS: Epidemiological study of 1194 subjects from the Northern Manhattan Study cohort, a prospective community-based study designed to investigate risk factors for vascular disease in different race-ethnic groups. RESULTS: Subjects with carotid plaque had higher corrected serum calcium levels within the normal range than those without carotid plaque (2.21+/-0.09 mmol/L versus 2.19+/-0.09 mmol/L, p<0.002). The relationship between carotid plaque and serum calcium persisted after adjustment for traditional cardiovascular risk factors. Subjects in the top quintile of maximal carotid plaque thickness (>or=1.7 mm) were more likely to be in the highest quintile of serum calcium level (OR=1.64, 95% CI=1.17-2.29, p<0.004). The interaction of age and corrected serum calcium was the most significant predictor of carotid plaque thickness when traditional vascular risk factors were considered (p<0.001). CONCLUSIONS: Serum calcium levels in a multi-ethnic population of older men and women were positively associated with carotid plaque thickness, a powerful early predictor of clinical coronary and cerebrovascular events. (+info)
The fate of the external carotid artery after carotid artery stenting. A follow-up study with duplex ultrasonography.
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OBJECTIVE: To evaluate the long-term effect of carotid angioplasty and stenting (CAS) of the internal carotid artery (ICA) on the ipsilateral external carotid artery (ECA). SUBJECTS AND METHODS: We prospectively registered the pre- and post-interventional duplex scans obtained from 312 patients (mean age 70 years) who underwent CAS. Duplex scans were scheduled the day before CAS, 3 and 12 months post-procedurally and yearly thereafter, to study progression of obstructive disease in the ipsilateral ECA compared to the contralateral ECA. The duplex ultrasound criteria used to identify ECA stenosis >or=50% were Peak Systolic Velocities of >or=125 cm/s. RESULTS: Preprocedural evaluation of the ipsilateral ECA demonstrated >or=50% stenosis in 32.7% of cases vs 30% contralateral. Both ipsilateral and contralateral 3 (1%) ECA occlusions were noted. After stenting 5 (1.8%) occlusions were seen vs 1% contralateral. No additional ipsilateral occlusions and 2 additional contralateral occlusions were noted at extended follow-up. The prevalence of >or=50% stenosis of the ipsilateral ECA (Kaplan-Meier estimates) progressed from 49.1% at 3, to 56.4%, 64.7%, 78.2%, 72.3%, and 74% at 12, 24, 36, 48, and 60 months respectively. Contralateral prevalences were 31.3%, 37.7%, 41.7%, 43.1%, 46.0%, and 47.2% respectively (p<0.001). Progression of stenosis was more pronounced in 234 patients (75%) with overstenting of the carotid bifurcation (p=0.004). CONCLUSION: Our results show that significant progression of >or=50% stenosis in the ipsilateral ECA occurs after CAS. There was greater progression of disease in the ipsilateral compared with the contralateral ECA. Progression of disease in the ECA did not lead to the occurrence of occlusion during follow up. (+info)