Acute endovascular reperfusion treatment in patients with ischaemic stroke and large-vessel occlusion (Denmark 2011-2017).

BACKGROUND AND PURPOSE: Acute endovascular reperfusion treatment (aERT) of stroke patients with large-vessel occlusions is efficacious and safe according to several clinical trials. Data on outcome and safety of aERT in daily clinical routine are warranted and, in this study, we present national data from Denmark during 2011-2017. METHODS: National data for Denmark from 2011 to 2017 on all aERT procedures in patients with acute ischaemic stroke and computed tomography angiography/magnetic resonance angiography-verified large-vessel occlusion were derived from the Danish Stroke Registry, a national clinical quality registry to which reporting is mandatory for all hospitals treating stroke patients. Outcome (modified Rankin Scale score) after 3 months, including time of death, was assessed prospectively based on clinical examination or the Danish Civil Registration System. RESULTS: During the 7 years of observation, a total of 1720 patients were treated with aERT. The annual number of procedures increased from 128 in 2011 to 409 in 2017. The median age was 70 years, 58% were males and median National Institutes of Health Stroke Scale score at baseline was 16. Median time from symptom onset to groin puncture was 238 min with a decreasing trend during the years. Successful recanalization was reported in 1306 (76%) patients. At 3-month follow-up, an modified Rankin Scale score of 0-2 was reported in 46% of patients, whereas 14% of patients had died. CONCLUSION: Routine data on aERT in acute ischaemic stroke in Denmark from 2011 to 2017 suggest that the procedure is safe and efficacious.

RAAS and stress markers in acute ischemic stroke: preliminary findings.

OBJECTIVES: Angiotensin II type 1 receptor blockade has neuroprotective effects in animal stroke models, but no effects in clinical stroke trials. We evaluated cerebral and peripheral changes in the renin angiotensin aldosterone system (RAAS) and stress responses in acute ischemic stroke patients. MATERIALS AND METHODS: Blood from a jugular and cubital vein was collected within 48 h of stroke onset, after 24 and 48 h, and renin, angiotensin I, angiotensin II, aldosterone, norepinephrine, epinephrine, and cortisol were measured. Post-stroke cubital vein samples were collected after 8 (4.7-10) months. RESULTS: The acute systolic blood pressure was significantly increased, 148 (141-168) vs 140 (130-147) mmHg post-stroke. Angiotensin I, renin and aldosterone levels were significantly lower, angiotensin II was unchanged, and ACE activity was higher in the acute phase compared to post-stroke. No differences in RAAS were detected between jugular and cubital plasma levels. Jugular venous plasma levels of epinephrine and cortisol were elevated in the acute phase compared to cubital levels (P < 0.05). CONCLUSION: Increased epinephrine and cortisol levels in the jugular vein blood may reflect a higher peripheral turnover. The observed changes in RAAS in the acute stroke phase are consistent with responses to increased blood pressure.

The effect of pelvic floor muscle training on sexual function in men with lower urinary tract symptoms after stroke.

BACKGROUND: Erectile dysfunction and lower urinary tract symptoms (LUTS) are common sequelae in men after stroke. OBJECTIVE: The objective of this study was to evaluate the effect of pelvic floor muscle training (PFMT) on measured erectile function as an indicator of sexuality in men with LUTS after stroke. METHOD: A sample of 516 men with stroke was invited to participate in this single-blinded, randomized controlled trial according to in- and exclusion criteria. This resulted in 31 participants who were randomized to either a Treatment Group (n = 16) or a Control Group (n = 15). The intervention included 12♣weeks of PFMT. The effect was measured on the International Index of Erectile Function (IIEF-5) questionnaire. RESULTS: Thirty participants (median age: 68 years; interquartile range: 60-74 years) completed the study, 15 in each group. The results of the IIEF-5 sum score showed a significant improvement (P < 0.04) from pre-test to post-test in the Treatment Group, but not in the Control Group. Within pre-test and 6-month follow-up, the median sum score decreased in both groups, worsened in the Control Group [Treatment Group, 3 (17%) versus Control Group, 5 (31%)]. There were differences between the groups at post-test and at follow-up, but they were not statistically significant. CONCLUSION: The results showed that, as measured by erectile function in men with LUTS after stroke, PFMT may have short-term and long-term effect, although no statistically significant effect was demonstrated between the groups.

Impact of the circadian clock on fibrinolysis and coagulation in healthy individuals and cardiovascular patients - A systematic review.

INTRODUCTION: Human body functions exhibit a circadian rhythm generated in peripheral cells and synchronized by the suprachiasmatic nucleus (SCN), which mostly is entrained by the daily light/dark cycles. Activity, meals and posture are capable of interfering with the endogenous circadian rhythm of coagulation parameters. An increasing number of human disorders show a circadian component, and epidemiological studies find cardiovascular events to peak in the morning hours. The aim was to review the circadian rhythms impact on fibrinolysis and coagulation in healthy individuals and cardiovascular patients. MATERIALS AND METHODS: A total number of 25 studies were identified where 8 enrolled cardiovascular patients with or without healthy individuals. Using a MeSH-search in MEDLINE PubMed. Only original peer-reviewed papers were included. RESULTS: Results showed substantial variance with respect to exhibition of circadian rhythms and/or peak/trough times. Circadian rhythms of fibrinolysis were less pronounced in cardiovascular patients than in healthy individuals with decreased levels in the morning hours compared to healthy inducing higher risk of blood clotting. CONCLUSIONS: Because of small studied group sizes and failure to control for entraining factors, larger studies are needed to fully establish the effects of the circadian rhythm on especially coagulation. The findings of chronobiologic rhythms in coagulation and fibrinolysis could suggest a need for a chrono-pharmacological approach when treating/preventing cardiovascular diseases.

Specialized Outpatient Clinic vs Stroke Unit for TIA and Minor Stroke: A Cohort Study.

Objective: To evaluate the effects of an outpatient clinic set-up for minor stroke/TIA using subsequent admission of patients at 'high risk' of re-stroke.Methods: A cohort study of all patients with suspected minor stroke/TIA seen in an outpatient clinic at Aarhus University Hospital, Denmark, between September 2013 and August 2014. Stroke patients were compared to historic (same hospital) and contemporary (another comparable hospital) matched, hospitalized controls on the non-prioritized outcomes: Length-of-stay, re-admissions, care quality (10 process-performance measures) and mortality. TIA patients were compared to contemporary matched, hospitalized controls.Following complete diagnostic work-up, patients with stroke/TIA were classified into 'low'/high risk' of re-stroke ≤7 days. RESULTS: We analyzed 1,076 consecutive patients of whom 253 (23.5%) were subsequently admitted to the stroke ward. Stroke/TIA was diagnosed in 215/171 patients, respectively. Fifty-six percent (121/215) of the stroke patients were subsequently admitted to the stroke ward. Comparison with the historic stroke cohort (n=191) showed a shorter acute hospital stay for the strokes (median 1 vs 3 days); adjusted length-of-stay ratio 0.49 (95% CI 0.33-0.71). Furthermore, 30-day readmission rate was 3.2% vs 11.6%; adjusted hazard ratio 0.23 (0.09-0.59); and care quality was higher with a risk ratio of 1.30 (1.15-1.47). The comparison of stroke and TIAs to contemporary controls showed similar results. Only one patient in the 'low risk' category and not admitted experienced stroke within 7 days (0.6%). CONCLUSIONS: An outpatient clinic set-up for patients with minor stroke/TIA yields shorter acute hospital stay, lower re-admissions rates, and better quality than hospitalization in stroke units. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that a neurovascular specialist driven outpatient clinic for minor stroke/TIA patients with the ability of subsequent admission is safe and yields shorter acute hospital stay, lower re-admissions rates, and better quality than hospitalization in stroke units.

Calcitonin gene-related peptide (CGRP) levels during glyceryl trinitrate (GTN)-induced headache in healthy volunteers.

The role of nitric oxide (NO) in migraine has been studied in the experimental glyceryl trinitrate (GTN)-infusion headache model. We hypothesized that GTN-induced headache may activate the trigeminovascular system and be associated with increased levels of sensory neuropeptides, including calcitonin gene-related peptide (CGRP). CGRP, vasoactive intestinal peptide (VIP), neuropeptide Y (NPY) and somatostatin plasma levels were measured before and after placebo/sumatriptan injection and during GTN-induced headache. Following a double-blind randomized cross-over design, 10 healthy volunteers received subcutaneous sumatriptan 6 mg or placebo. This was succeeded by 20 min of GTN (0.12 µg kg(-1) min(-1)) infusion. At baseline no subject reported headache (using verbal rating scale from 0 to 10) and the jugular CGRP-like immunoreactivity (-LI) level was 18.6 ± 2.5 pmol/l. After a 20-min intravenous infusion of GTN 0.12 µg kg(-1) min(-1), median peak headache intensity was 4 (range 2-6) (P < 0.05), while jugular CGRP-LI levels were unchanged (19.0 ± 2.8 pmol/l; P > 0.05). There were no changes in VIP-, NPY- or somatostatin-LI. In conclusion, the NO donor GTN appears not to induce headache via immediate CGRP release.

Nitroglycerin provocation in normal subjects is not a useful human migraine model?

Provoking delayed migraine with nitroglycerin in migraine sufferers is a cumbersome model. Patients are difficult to recruit, migraine comes on late and variably and only 50-80% of patients develop an attack. A model using normal volunteers would be much more useful, but it should be validated by testing the response to drugs of known efficacy in acute migraine. Furthermore, treatment during headache rather than pretreatment is the most naturalist method. To fulfil these requirements we used continuous long-lasting infusion of glyceryl trinitrate (GTN) 0.2 microg kg-1 min-1 for 140 min and gave aspirin 1000 mg, zolmitriptan 5 mg or placebo to normal healthy volunteers. The design was double-blind, placebo-controlled three-way crossover. Our hypothesis was that these drugs would be effective in the treatment of the mild constant headache induced by long-lasting GTN infusion. The headaches did not fulfil the International Headache Society diagnostic criteria for migraine without aura. Moreover, there was no effect on headache of either zolmitriptan or aspirin. Thus our hypothesis was disproved and we conclude that our model is not valid for the testing of new acute antimigraine drugs. Our experiment suggests that headache caused by direct nitric oxide (NO) action in the continued presence of NO is very resistance to analgesics and to specific acute migraine treatments. This suggests that NO works very deep in the cascade of events associated with vascular headache, whereas tested drugs work higher in the cascade. The model suggested here should therefore be tested with other headache/migraine-provoking agents that supposedly work higher in the cascade of events. The need for human models persists, but the solution to this problem is still pending.

Delayed migraine-like headache in healthy volunteers after a combination of acetazolamide and glyceryl trinitrate.

Glyceryl trinitrate (GTN) is a pro-drug dissociating nitric oxide throughout the body. It dilates cephalic arteries without increasing cerebral blood flow (CBF). GTN induces headache in healthy volunteers and migraine attacks in migraineurs. Acetazolamide (Az) increases CBF but does not dilate cerebral arteries. The hypothesis tested here was that Az, by dilating cerebral arterioles but not arteries and thereby decreasing pulsatile stretching of the wall of the large arteries and their perivascular sensory nerves, would reduce or prevent the GTN-induced headache We tested this hypothesis in 14 healthy volunteers. In a randomized, double-blind, cross-over study, they were pretreated with Az or placebo followed on both study days by a GTN infusion of 0.5 microg kg(-1) min(-1) for 20 min. Headache was scored on a verbal rating scale and a headache diary was kept for 12 h. Mean blood velocity of the middle cerebral artery was measured (transcranial Doppler). Our hypothesis was disproved, as Az did not decrease GTN-induced headache. Unexpectedly but interestingly, GTN combined with Az induced more delayed headache than GTN alone. Furthermore, a migraine-like headache was observed in three volunteers, who did not develop migraine after GTN alone. The fact that a suitable pharmacological intervention may trigger migraine in individuals with no prior migraine may suggest that the ability to develop migraine without aura is a quantitative genetic trait.

Lack of effect of norepinephrine on cranial haemodynamics and headache in healthy volunteers.

Stress is a provoking factor for both tension-type headache and migraine attacks. In the present single-blind study, we investigated if stress induced by norepinephrine (NE) could elicit delayed headache in 10 healthy subjects and recorded the cranial arterial responses. NE at a dose of 0.025 microg kg(-1) min(-1) or placebo was infused for 90 min and the headache was followed for 14 h. Blood flow velocity in the middle cerebral artery (measured with transcranial Doppler) and diameters of the temporal artery and the radial artery (measured with ultrasound) were followed for 2 h. There were no changes in these arterial parameters after NE. In both treatment groups three subjects developed delayed headaches. Thus, stress by NE infusion did not result in delayed headache.

Prednisolone reduces nitric oxide-induced migraine.

BACKGROUND AND PURPOSE: Glyceryl trinitrate (GTN) induces delayed migraine attacks in migraine patients. The purpose of this study was to investigate whether pre-treatment with prednisolon could decrease this effect of GTN. METHODS: In this double-blind, randomized and placebo-controlled, crossover study 15 migraineurs with migraine without aura were pre-treated with 150 mg of prednisolone or placebo followed by a 20-min infusion of GTN (0.5 ug/kg/min). One hour after the GTN-infusion, the participants were sent home, but continued to rate headache and possible associated symptoms by filling out a headache diary every hour for 12 h. There were two equal primary efficacy end-points: frequency of delayed migraine and intensity of delayed headache. RESULTS: Nine patients experienced a GTN headache fulfilling the diagnostic criteria for migraine without aura on the placebo day compared with four patients on the prednisolone day (P = 0.14). Prednisolone pre-treatment did not alter the summed or peak immediate headache responses to GTN significantly (P = 0.08, P = 0.07), whereas the peak headache scores during the following 12 h were significantly lower after prednisolone pre-treatment (median peak score = 1, range 0-8) compared with placebo (median = 4, range 0-8) (P < 0.01). There was no difference between the two treatment days in the effect of GTN on blood flow velocity of the middle cerebral artery (a decrease) or on the dilation of the superficial temporal artery or the radial artery. CONCLUSION: Pre-treatment with prednisolone did not reduce the immediate GTN-induced headache, did not inhibit the frequency of delayed headache but significantly decreased the intensity of delayed GTN-induced headache. These findings suggest that GTN causes induction of inflammatory mediators, and that this is the mechanism of delayed GTN-induced migraine. They also support a role of inflammatory mediators in spontaneous migraine attacks.

Mechanical Thrombectomy with the Embolus Retriever with Interlinked Cages in Acute Ischemic Stroke: ERIC, the New Boy in the Class.

BACKGROUND AND PURPOSE: The Embolus Retriever with Interlinked Cages (ERIC) device is a novel stent retriever for mechanical thrombectomy. It consists of interlinked cages and could improve procedural benchmarks and clinical outcome compared with classic stent retrievers. This study compares the rates of recanalization, favorable clinical outcome, procedural adverse events, and benchmarks between the ERIC device and classic stent retrievers. MATERIALS AND METHODS: From 545 patients treated with thrombectomy between 2012 and 2015, 316 patients were included. The mean age was 69 ±13 years, the mean baseline NIHSS score was 17 ± 5, and 174 (55%) were men. The ERIC was used as the primary thrombectomy device in 59 (19%) patients. In a propensity score matched analysis including the NIHSS score, clot location, delay to groin puncture, neurointerventionalist, and anesthetic management, 57 matched pairs were identified. RESULTS: Patients treated with the ERIC device compared with classic stent retrievers showed equal rates of recanalization (86% versus 81%, P = .61), equal favorable 3-month clinical outcome (mRS 0-2: 46% versus 40%, P = .71), and procedural adverse events (28% versus 30%, P = 1.00). However, in patients treated with the ERIC device, thrombectomy procedures were less time-consuming (67 versus 98 minutes, P = .009) and a rescue device was needed less often (18% versus 39%, P = .02) compared with classic stent retrievers. CONCLUSIONS: Mechanical thrombectomy with the ERIC device is effective and safe. Rates of favorable procedural and clinical outcomes are at least as good as those with classic stent retrievers. Of note, the ERIC device might be time-saving and decrease the need for rescue devices. These promising results call for replication in larger prospective clinical trials.

Visual attention in posterior stroke and relations to alexia.

Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere, while attentional effects of more posterior lesions are less clear. Commonly, such deficits are investigated in relation to specific syndromes like visual agnosia or pure alexia. The aim of this study was to characterize visual processing speed and apprehension span following posterior cerebral artery (PCA) stroke. In addition, the relationship between these attentional parameters and single word reading is investigated, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Eight patients with unilateral PCA strokes (four left hemisphere, four right hemisphere) were selected on the basis of lesion location, rather than the presence of any visual symptoms. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific measurements of processing speed and apprehension span. All patients showed reductions in visual span contralateral to the lesion site, and four patients showed bilateral reductions in visual span despite unilateral lesions (2L; 2R). Six patients showed selective deficits in visual span, though processing speed was unaffected in the same field (ipsi- or contralesionally). Only patients with right hemifield reductions in visual span were impaired in reading, and this could follow either right or left lateralized stroke and was irrespective of visual field impairments. In conclusion, visual span may be affected bilaterally by unilateral PCA-lesions. Reductions in visual span may also be confined to one hemifield, and may be affected in spite of preserved visual processing speed. Furthermore, reduced span in the right visual field seems to be related to reading impairment in this group, regardless of lesion lateralization.

Altered peripheral vasodilator profile of nitroglycerin during long-term infusion of N-acetylcysteine.

OBJECTIVES: The aim of this study was to compare the short- and long-term effects of intravenous nitroglycerin plus placebo and nitroglycerin plus N-acetylcysteine on peripheral arteries, veins and microcirculation in humans. BACKGROUND: The thiol donor N-acetylcysteine may potentiate the hemodynamic response to nitrates in nitrate-tolerant and nontolerant patients. The vascular changes responsible for this effect are not clear. METHODS: Eight male volunteers were treated with nitroglycerin (0.1 microgram/kg per min) combined with N-acetylcysteine (2 g intravenously, followed by 5 mg/kg per h) or placebo for 23 h in a double-blind, randomized, crossover study. Venous volume, the diameter of the radial and temporal arteries, calf blood flow and subcutaneous blood flow were measured at baseline and repeated after 1 and 23 h of infusion. RESULTS: Prolonged coadministration of N-acetylcysteine and nitroglycerin potentiated the acute venodilator effect of nitroglycerin as estimated by changes in venous volume (nitroglycerin plus N-acetylcysteine, 4.45 +/- 0.36 ml/100 g; nitroglycerin plus placebo, 3.65 +/- 0.46 ml/100 g, mean +/- SEM, p < 0.05) and prevented development of tolerance as seen after 23 h of treatment with nitroglycerin plus placebo (4.35 +/- 0.25 vs. 3.47 +/- 0.41 ml/100 g, p < 0.05). N-acetylcysteine had no effect on nitroglycerin-induced changes in arterial diameters (p > 0.05) but significantly increased microcirculatory subcutaneous blood flow after 1 h (nitroglycerin plus N-acetylcysteine: 6.3 +/- 1.3 ml/100 g per min vs. nitroglycerin plus placebo: 3.5 +/- 0.3 ml/100 g per min, p < 0.05) and after 23 h (4.4 +/- 0.6 vs. 3.1 +/- 0.5 ml/100 g per min, p < 0.05). CONCLUSIONS: The results suggest that coadministration of nitroglycerin and N-acetylcysteine in humans 1) potentiates and preserves nitroglycerin-induced venodilation and 2) augments the effect of nitroglycerin on small resistance vessels (regulating subcutaneous blood flow) without affecting the response to nitroglycerin in middle-sized arteries. Both the development of nitrate tolerance and the administration of N-acetylcysteine significantly change the normal vasodilator profile of nitroglycerin in humans.

N-acetylcysteine enhances nitroglycerin-induced headache and cranial arterial responses.

The effects of N-acetylcysteine, a sulfhydryl group donor, on nitroglycerin-induced headache and dilation of temporal and radial arteries were investigated in 11 healthy volunteers. Nitroglycerin, 0.06 microgram/kg/min, was infused for 20 minutes immediately after and 120 minutes after pretreatment with N-acetylcysteine (100 mg/kg) or placebo. Arterial diameters were measured with high frequency ultrasound, and pain was scored by use of a previously evaluated 10-point scale. Plasma levels of free (n = 2) and total (n = 11) N-acetylcysteine were determined. N-Acetylcysteine potentiated the headache response (median headache score, 3 versus 1), and the headache retained its vascular characteristics. Temporal artery dilation was also potentiated by N-acetylcysteine, 139% +/- 3% versus 127% +/- 3% of baseline, whereas the radial artery was unaffected. The potentiation was most pronounced after the first nitroglycerin infusion (12% versus 4.5% compared with placebo). A prolonged dilation of the temporal artery was observed only after the first nitroglycerin infusion, when high levels of N-acetylcysteine were present.

Nitric oxide supersensitivity: a possible molecular mechanism of migraine pain.

Nitroglycerin, which may be regarded as a prodrug for nitric oxide, induces a mild to moderate headache in healthy subjects. In order to study whether migraine patients are more sensitive to nitric oxide than non-migrainous subjects, four different doses of intravenous nitroglycerin were given in a double blind design to 17 migraine patients, 17 age and sex matched healthy controls and 9 subjects with tension-type headache. The nitroglycerin-induced headache was significantly more severe in migraine sufferers, lasted longer and fulfilled diagnostic criteria for migraine more often. We have previously shown a similar supersensitivity to histamine which in human cerebral arteries activates endothelial H1 receptors and causes endothelial production of nitric oxide. Migraine patients are thus supersensitive to exogenous nitric oxide from nitroglycerin as well as to endothelially produced nitric oxide. It is suggested that nitric oxide may be partially or completely responsible for migraine pain.

Experimental and biological variation of three-dimensional transcranial Doppler measurements.

A new transcranial Doppler system (3-D Transscan, Eden Medizinische Elektronik) was evaluated in relation to sex, age, intersubject, interobserver, side-to-side, and day-to-day variation. Fifty-eight healthy volunteers participated (aged 18-80 yr). Mean velocity was higher in females than in males and decreased with age. The coefficient of variation in the middle cerebral artery was 26% between subjects, 20% between sides, 16% between days, 13% between observers, and 7% during 5 min. The coefficient of variation was higher in the anterior and posterior cerebral arteries. Bruits were heard in 35 subjects, 24 females and 11 males (P = 0.002). When middle cerebral artery velocity was monitored, high- and low-frequency oscillations were found, with a mean frequency of 5 and 1.6/min, respectively. These variations underline the necessity of standardized conditions and very carefully matched control groups in studies using transcranial Doppler. This is especially important when expected changes are small and easy to overlook, as in studies of normal physiological responses and migraine.

Small arteries can be accurately studied in vivo, using high frequency ultrasound.

We have validated measurements of diameters of the superficial temporal artery and other small arteries in man with a newly developed 20 MHz ultrasound scanner with A, B and M-mode imaging. The diameter of a reference object was 1.202 mm vs. 1.205 mm as measured by stereomicroscopy (nonsignificant). In vitro measurements of porcine carotid arteries could be reproduced with a mean interobserver difference of 0.008 mm, and the repeatability coefficient was 0.04 mm (1.4%). The frontal branch of the human superficial temporal artery (mean 1.24 mm) was measured with intraobserver repeatability coefficients of 0.18 mm (13.8%) to 0.31 mm (23.4%). The interobserver mean difference was 0.01 mm (0.69%) and the interobserver repeatability coefficient was 0.16 mm (11.1%). Pulsatile changes of the cross sectional area of the radial plus the ulnar artery averaged 0.93 mm2 compared to 0.63 mm2 by strain-gauge plethysmography (nonsignificant). Pulsations were 4.6% in the radial artery. We conclude that high frequency ultrasound provides an accurate and reproducible measure of the diameter of small and medium sized human arteries in vivo.

Determination of the luminal diameter of the radial artery in man by high frequency ultrasound: a methodological study.

The validity and reproducibility of measurements of the luminal diameter of the radial artery in man were investigated with Dermascan A, a 20 MHz ultrasound scanner. The luminal diameter of a reference object, a plastic tube, was measured with ultrasound to be 99.0% of stereomicroscopic measurements. By comparing the diameter of the reference object either filled with water or blood at 37 degrees C, the ultrasound velocity in human blood at 37 degrees C was calculated to be 1605 m/s. The intraobserver repeatability coefficients of in-vivo measurements of the radial artery in man were in the same range, whether measurements were repeated after 30 min (14%) or from day to day (12%). The interobserver repeatability coefficient was acceptable (15%) when the site of measurements was marked, whereas measurements without a mark resulted in a repeatability coefficient of 24%. The intravenous administration of 0.5 mg ergotamine tartrate to 5 subjects caused a decrease in the mean luminal diameter of the radial artery from 2.94 mm to 2.42 mm 1 h after ergotamine (p less than 0.05). This ultrasound method for measurements of the luminal diameter should thus be suitable for investigating the effects of physiological and pharmacological stimuli on the arteries per se.

[Effects of nitrogen oxide donor glyceryl trinitrate on pressure pain threshold in humans]. / Effekten af nitrogenoxiddonoren glyceryltrinitrat på humane smertetaerskler for tryk.

The purpose of the present study was to examine the effect of the nitric oxide (NO) donor glyceryl trinitrate (GTN) on nociceptive thresholds in man. On two different study days twelve healthy subjects received a stair case infusion of GTN (0.015, 0.25, 1.0, 2.0 micrograms/kg/min 20 min each dose) or placebo in a randomized double-blind cross-over design. Before the infusion and after 15 min of infusion on each dose, pressure pain detection- and tolerance thresholds were determined by pressure algometry in three different anatomic regions (finger, a temporal region with interposed myofascial tissue and a temporal region without interposed myofascial tissue). Relative to placebo the three higher GTN doses induced a decrease in both detection- and tolerance-thresholds in the temporal region with interposed myofascial tissue. No such changes were observed in the two other stimulated regions. These results could reflect central facilitation of nociception by NO. However, convergence of nociceptive input from pericranial myofascial tissue and from cephalic blood vessels dilated by NO may provide a more likely explanation.

Thrombolysis outcomes in acute ischemic stroke patients with prior stroke and diabetes mellitus.

BACKGROUND: Patients with concomitant diabetes mellitus (DM) and prior stroke (PS) were excluded from European approval of alteplase in stroke. We examined the influence of DM and PS on the outcomes of patients who received thrombolytic therapy (T; data from Safe Implementation of Thrombolysis in Stroke-International Stroke Thrombolysis Register) compared to nonthrombolyzed controls (C; data from Virtual International Stroke Trials Archive). METHODS: We selected ischemic stroke patients on whom we held data on age, baseline NIH Stroke Scale score (NIHSS), and 90-day modified Rankin Scale score (mRS). We compared the distribution of mRS between T and C by Cochran-Mantel-Haenszel (CMH) test and proportional odds logistic regression, after adjustment for age and baseline NIHSS, in patients with and without DM, PS, or the combination. We report odds ratios (OR) for improved distribution of mRS with 95% confidence interval (CI) and CMH p value. RESULTS: Data were available for 29,500 patients: 5,411 (18.5%) had DM, 5,019 had PS (17.1%), and 1,141 (5.5%) had both. Adjusted mRS outcomes were better for T vs C among patients with DM (OR 1.45 [1.30-1.62], n = 5,354), PS (OR 1.55 [1.40-1.72], n = 4,986), or concomitant DM and PS (OR 1.23 [0.996-1.52], p = 0.05, n = 1,136), all CMH p < 0.0001. These are comparable to outcomes between T and C among patients with neither DM nor PS: OR = 1.53 (1.42-1.63), p < 0.0001, n = 19,339. There was no interaction on outcome between DM and PS with alteplase treatment (tissue plasminogen activator × DM × PS, p = 0.5). Age ≤80 years or >80 years did not influence our findings. CONCLUSIONS: Outcomes from thrombolysis are better than the controls among patients with DM, PS, or both. We find no statistical justification for the exclusion of these patients from receiving thrombolytic therapy.