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Ischaemic Events (ischaemic + event)
Selected AbstractsPreconditioning and postconditioning: new strategies for cardioprotectionDIABETES OBESITY & METABOLISM, Issue 6 2008D. J. Hausenloy Despite optimal therapy, the morbidity and mortality of coronary heart disease (CHD) remains significant, particularly in patients with diabetes or the metabolic syndrome. New strategies for cardioprotection are therefore required to improve the clinical outcomes in patients with CHD. Ischaemic preconditioning (IPC) as a cardioprotective strategy has not fulfilled it clinical potential, primarily because of the need to intervene before the index ischaemic event, which is impossible to predict in patients presenting with an acute myocardial infarction (AMI). However, emerging studies suggest that IPC-induced protection is mediated in part by signalling transduction pathways recruited at time of myocardial reperfusion, creating the possibility of harnessing its cardioprotective potential by intervening at time of reperfusion. In this regard, the recently described phenomenon of ischaemic postconditioning (IPost) has attracted great interest, particularly as it represents an intervention, which can be applied at time of myocardial reperfusion for patients presenting with an AMI. Interestingly, the signal transduction pathways, which underlie its protection, are similar to those recruited by IPC, creating a potential common cardioprotective pathway, which can be recruited at time of myocardial reperfusion, through the use of appropriate pharmacological agents given as adjuvant therapy to current myocardial reperfusion strategies such as thrombolysis and primary percutaneous coronary intervention for patients presenting with an AMI. This article provides a brief overview of IPC and IPost and describes the common signal transduction pathway they both appear to recruit at time of myocardial reperfusion, the pharmacological manipulation of which has the potential to generate new strategies for cardioprotection. [source] Stent-protected angioplasty in asymptomatic carotid artery stenosis vs. endarterectomy: SPACE2 , a three-arm randomised-controlled clinical trialINTERNATIONAL JOURNAL OF STROKE, Issue 4 2009T. Reiff Moderate to severe (,70%) asymptomatic stenosis of the extracranial carotid artery leads to an increased rate of stroke of approximately 11% in 5 years. Patients with asymptomatic carotid stenosis, however, are also at a higher risk of nonstroke vascular events. The estimated annual risks of such events in patients with asymptomatic stenosis are 7% for a coronary ischaemic event and 4,7% for overall mortality. The superiority of carotid endarterectomy compared with medical treatment in symptomatic carotid disease is established, provided that the surgical procedure can be performed with a perioperative morbidity and mortality of <6%. The advantage of carotid endarterectomy for asymptomatic patients is less established. An alternative treatment, carotid artery stenting, has been developed. This treatment is used frequently in both symptomatic and asymptomatic patients. In the last decade, major advantages in medical primary prevention of cerebrovascular and cardiovascular disease have been accomplished. The control groups in the large trials for asymptomatic carotid artery disease (ACAS and ACST) originate from more than a decade ago and, for the most part, have not received a medical primary prevention strategy that would now be considered the standard according to current national and international guidelines. For this reason, a three-arm trial (SPACE2; http://www.space-2.de) with a hierarchical design and a recruitment target of 3640 patients is chosen. Firstly, a superior trial of intervention (carotid artery stenting or carotid endarterectomy) vs. state-of-the-art conservative treatment is designed. In case of superiority of the interventions, a noninferiority end-point will be tested between carotid artery stenting and carotid endarterectomy. This trial is registered at Current Controlled Trials ISRCTN 78592017. [source] HYPERBARIC OXYGENATION APPLIED IMMEDIATELY AFTER CORONARY OCCLUSION REDUCES MYOCARDIAL NECROSIS AND ACUTE MORTALITY IN RATSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 5-6 2009Leonardo Dos Santos SUMMARY 1Because in ischaemia there is a critical lack of O2, it has been reasoned that increasing O2 delivery to the ischaemic myocardium could serve as adjunctive therapy for acute myocardial infarction (MI). Accordingly, in the present study, the effect of early hyperbaric oxygenation (HBO) on mortality and MI size after coronary occlusion was examined in rats. 2After coronary occlusion, male Wistar rats were randomly assigned to receive either HBO for 1 h in a hyperbaric chamber (100% O2 at 253 kPa; n = 106) or ambient O2 as the control (n = 111). The extent of myocardial necrosis was assessed (triphenyltetrazolium) immediately after treatment in the HBO (n = 50) and control (n = 47) groups. The remaining rats were evaluated 24 h after occlusion to enable calculation of MI size and mortality. 3Immediately after therapy, the size of the MI was significantly greater in the control group compared with that in the HBO group (40 ± 3 vs 27 ± 2% of the left ventricle (LV), respectively; P < 0.001). The 24 h mortality of control rats was higher than that of HBO rats (34 vs 16%, respectively; P = 0.02). Control rats that survived 24 h had a larger MI than did HBO rats that survived 24 h (40 ± 4 vs 29 ± 3% of the LV, respectively; P = 0.005). Furthermore, large necrotic areas (> 40% of the LV) were more frequent in control than HBO rats (55 vs 27% of infarcted hearts, respectively; P = 0.01). There was less pulmonary congestion observed in HBO rats compared with control rats. 4In conclusion, early therapy with HBO during the onset of an acute ischaemic event decreases the necrotic area and reduces acute mortality. These data support further investigation of HBO as an adjuvant therapy for acute MI. [source] Impaired glucose regulation, elevated glycated haemoglobin and cardiac ischaemic events in vascular surgery patientsDIABETIC MEDICINE, Issue 3 2008H. H. H. Feringa Abstract Aims Cardiac morbidity and mortality is high in patients undergoing high-risk surgery. This study investigated whether impaired glucose regulation and elevated glycated haemoglobin (HbA1c) levels are associated with increased cardiac ischaemic events in vascular surgery patients. Methods Baseline glucose and HbA1c were measured in 401 vascular surgery patients. Glucose < 5.6 mmol/l was defined as normal. Fasting glucose 5.6,7.0 mmol/l or random glucose 5.6,11.1 mmol/l was defined as impaired glucose regulation. Fasting glucose , 7.0 or random glucose , 11.1 mmol/l was defined as diabetes. Perioperative ischaemia was identified by 72-h Holter monitoring. Troponin T was measured on days 1, 3 and 7 and before discharge. Cardiac death or Q-wave myocardial infarction was noted at 30-day and longer-term follow-up (mean 2.5 years). Results Mean (± sd) level for glucose was 6.3 ± 2.3 mmol/l and for HbA1c 6.2 ± 1.3%. Ischaemia, troponin release, 30-day and long-term cardiac events occurred in 27, 22, 6 and 17%, respectively. Using subjects with normal glucose levels as the reference category, multivariate analysis revealed that patients with impaired glucose regulation and diabetes were at 2.2- and 2.6-fold increased risk of ischaemia, 3.8- and 3.9-fold for troponin release, 4.3- and 4.8-fold for 30-day cardiac events and 1.9- and 3.1-fold for long-term cardiac events. Patients with HbA1c > 7.0% (n = 63, 16%) were at 2.8-fold, 2.1-fold, 5.3-fold and 5.6-fold increased risk for ischaemia, troponin release, 30-day and long-term cardiac events, respectively. Conclusions Impaired glucose regulation and elevated HbA1c are risk factors for cardiac ischaemic events in vascular surgery patients. [source] Long-term follow-up of patients with asymptomatic occlusion of the internal carotid artery with good and impaired cerebral vasomotor reactivityEUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2010I. Kimiagar Background:, Cerebral hemodynamic status might be prognostic for either the symptomatic or asymptomatic course of carotid occlusive disease. It is determined by evaluating cerebral vasomotor reactivity (VMR). We assessed VMR in asymptomatic patients with total occlusion of the internal carotid artery (ICA) and followed them to evaluate the role of impaired VMR in predicting ischaemic stroke (IS). Methods:, Thirty-five patients (21 men, mean age ± SD 68 ± 7.5 years) with unilateral asymptomatic ICA occlusion were studied by transcranial Doppler and the Diamox test (intravenous 1.0 g acetazolamide) and followed for 48 months or until reaching the end-points of IS, transient ischaemic attack, or vascular death. VMR% was evaluated by recording the percent differences in peak systolic blood flow velocities in each middle cerebral artery at baseline and after Diamox administration. Results:, Based on VMR% calculations, 14 (40%) patients had good VMRs and 21 (60%) had impaired VMRs. The global annual risk of ipsilateral ischaemic events was 5.7%. The annual ipsilateral ischaemic event risk was 1.8% in patients with good VMRs, whilst it was 7.1% in patients with impaired VMRs. An impaired VMR was significantly correlated with ipsilateral IS (Kaplan,Meier log rank statistic, P = 0.04). Conclusions:, Our results support the value of VMR assessment for identifying asymptomatic patients with carotid occlusion who belong to a high-risk subgroup for IS. New trials using extracranial-to-intracranial bypass surgery in patients with asymptomatic ICA occlusion and impaired VMRs are warranted. [source] Early treatment after a symptomatic event is not associated with an increased risk of stroke in patients undergoing carotid stentingEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2008K. Gröschel A recently symptomatic carotid artery stenosis carries a high risk of subsequent ischaemic events and thus requires rapid treatment. We investigated the influence of the time delay between the last symptomatic event of a carotid stenosis and subsequent carotid artery stenting (CAS) with respect to the combined 30-day outcome of stroke and death. In a group of 320 patients undergoing CAS the median delay before the intervention was 19 days (interquartile range 10,36) and the combined 30-day complication rate was 8.4%. Time delay was not significantly associated with peri-procedural complications, regardless of whether this variable was dichotomized (<14 days and ,14 days), separated into interquartile ranges or analysed as a continuous variable. Our results indicate that early CAS is not associated with an increased complication rate in patients with a recently symptomatic carotid stenosis. Thus, if CAS has been selected as the treatment modality for a patient, it should be performed as soon as possible to maximize the benefit of the intervention in reducing the risk of stroke. [source] Prevalence and outcome of asymptomatic carotid stenosis: a population-based ultrasonographic studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2002P. P. Mineva The aims of this epidemiological population-based cohort study were to examine the prevalence and outcomes of asymptomatic carotid stenosis (ACS) detected by duplex scanning and its relations to other vascular risk factors. A total of 500 volunteers, 200 men and 300 women, without signs and symptoms of cerebrovascular disease, aged 50,79 years, were enrolled in the study. The prevalence of ACS of 50% or greater was 6.4%. Only severe carotid stenosis was detected in 0.4% of the subjects examined. Significant relationships between ACS and coronary heart disease (CHD) [odds ratio (OR)=8.00], peripheral arterial disease (PAD) (OR=3.66), cigarette smoking in men (OR=4.39) and obesity in women (OR=0.31) were found. The biennial incidence rate of cerebral ischaemic events was 9.4%. A progression of ACS was revealed in 14% and a regression in 6.25% of the subjects. The patients with progressing ACS to more than 70% diameter reduction reached the end-points. Follow-up with repeated duplex scans in patients with advancing ACS of 50% or greater, especially smokers with CHD and PAD, is recommended. [source] Which parameters differ in very old patients with chronic atrial fibrillation treated by anticoagulant or aspirin?FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 5 2008Antithrombotic treatment of atrial fibrillation in the elderly Abstract The objective was to determine the main parameters taken into account for the decision of antithrombotic treatment of atrial fibrillation (AF) by vitamin K antagonist or aspirin. This was a prospective clinical study of four clinical services of geriatric medicine. Two hundred and nine inpatients, 84.7 ± 7 years (women 60.8%), with chronic AF were included. The patients were distributed into two groups (anticoagulant or aspirin) according to medical decision. All the decision criteria for treatment were recorded: cardiopathy, conditions of life, clinical examination (nutrition and autonomy, mini-mental state examination (MMSE), walking evaluation, comorbidity), subjective evaluation of risk of falls and glomerular filtration rate. The thromboembolic risk and the bleeding risk, evaluated subjectively for each patient, were compared with two scores of thrombo-embolic risk and bleeding risk. The evolution of the patients was recorded after 3 months. Student's t -test and chi-squared tests were used for statistical analysis. One hundred and two patients (48.8%) received anticoagulant and 107 patients received aspirin. Patients in the aspirin group were significantly older (86.5 ± 6.5 vs. 82.9 ± 7.1 years), with more frequent social isolation, higher systolic blood pressure, and had more important subjective bleeding risk and risk of falls. Patients in the anticoagulant group had significantly more valvulopathies and a more important subjective thromboembolic risk. Thrombo-phlebitis antecedents, dementia, denutrition and walking alterations were only slightly more frequent in patients in the aspirin group. Physicians underestimated thromboembolic risk (one-third of patients) and they overestimated bleeding risk (half of the patients). After 3 months, the two groups did not significantly differ for death, bleeding or ischaemic events. In common practice, the decision of antithrombotic treatment for AF should take into account not only cardiovascular but also geriatric criteria. [source] The challenge of ST-segment elevation myocardial infarctionINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 12 2007M. Cohen Summary Background/introduction:, Acute coronary syndromes (ACS) represent a spectrum of ischaemic myocardial events that share a similar pathophysiology. ST-segment elevation myocardial infarction (STEMI), the most severe form of ACS short of sudden cardiac death, is a significant public health problem with an estimated 500,000 STEMI events every year in the United States. Treatment/therapy:, The mortality and morbidity associated with STEMI is significant. Early reperfusion therapy is the most important aspect of the treatment of STEMI. There are two main methods of reperfusion therapy: percutaneous coronary intervention (PCI) and fibrinolytic therapy, with PCI being the preferred method. In addition to standard reperfusion therapy, antithrombotics (unfractionated heparin and low molecular weight heparins) and antiplatelet agents (aspirin, clopidogrel and glycoprotein IIb/IIIa inhibitors) are critical adjuncts, effective in the treatment of acute STEMI. Conclusions:, The survival of patients with STEMI depends on rapid diagnosis and optimal early treatment. Guidelines for the management of patients with STEMI recommend PCI within 90 min of presentation and that fibrinolytics are administered within 30 min. However, only a fraction of patients undergo reperfusion within the recommended time. Improvements in protocols for identifying STEMI cases are therefore required to allow reperfusion therapy to be initiated sooner. Secondary prevention is another important aspect of STEMI management, and patients should be encouraged to adopt strategies that reduce the risk of subsequent ischaemic events. [source] Guidelines on the management of secondary prophylaxis of vascular events in stable patients in primary careINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2004D.J. Betteridge Summary Atherothrombosis, thrombus formation superimposed on an existing atherosclerotic plaque, is an acute process leading to ischaemic events such as myocardial infarction, stroke and critical limb ischaemia. Patients presenting with clinical conditions associated with atherothrombosis are at increased risk of subsequent vascular events. The beneficial effect of antiplatelet therapies for short-term and long-term secondary prevention of atherothrombotic events has been established. These guidelines aim to provide evidence-based recommendations that will assist in the antiplatelet-mediated secondary prophylaxis of vascular events in patients with stable cardiovascular disease treated in the primary healthcare setting. Medline and the Cochrane library were accessed using free-text strategies in the domains of antiplatelet agents and antithrombotics. Development of the guidelines was driven by a series of Steering Committee meetings, in which the quality of relevant studies was assessed and identified using narrative summary. These guidelines present evidence and recommendations for the treatment of numerous atherothrombotic indications depending on individual patient circumstances. [source] Patient flow to carotid endarterectomy: hastening the patient journeyANZ JOURNAL OF SURGERY, Issue 6 2010Manar Khashram Abstract Background:, Early carotid endarterectomy (CEA) after stroke or transient ischaemic attack is the proposed standard of care to prevent recurrent ischaemic events in selected patients. The aim of this study was to investigate if this standard is achieved in a tertiary vascular unit. Methods:, This was a clinical audit. CEAs performed from 1 January 2006 to 31 December 2008 at Christchurch hospital were identified. The value stream from initial presentation to surgery was mapped in two phases (phase 1; 2006,2007 and phase 2; 2008). Patients who had carotid intervention for asymptomatic carotid lesions were excluded. Results:, The relevant patient journey was documented in 81 patients (55 phase 1; 26 phase 2). Median time from initial presentation to carotid ultrasound was 5 days in phase 1 and 6 days in phase 2. Time from presentation to vascular surgery review was 22 days in phase 1 and 13 days in phase 2. Time from presentation to CEA significantly reduced from 83 to 32 days between phases (P < 0.005). Conclusions:, There has been a significant decrease in time from presentation to operation between phase 1 and 2. The most significant change is reduced delay between vascular surgery review and CEA. There has been no improvement in urgency of referral for imaging or surgical review. This part of the patient journey is a target for improvement. [source] Using diffusion MRI for measuring the temperature of cerebrospinal fluid within the lateral ventriclesACTA PAEDIATRICA, Issue 2 2010LR Kozak Abstract Aim:, Hypothermia is often induced to reduce brain injury in newborns, following perinatal hypoxic,ischaemic events, and in adults following traumatic brain injury, stroke or cardiac arrest. We aimed to devise a method, based on diffusion-weighted MRI, to measure non-invasively the temperature of the cerebrospinal fluid in the lateral ventricles. Methods:, The well-known temperature dependence of the water diffusion constant was used for the estimation of temperature. We carried out diffusion MRI measurements on a 3T Philips Achieva Scanner involving phantoms (filled with water or artificial cerebrospinal fluid while slowly cooling from 41 to 32°C) and healthy adult volunteers. Results:, The estimated temperature of water phantoms followed that measured using a mercury thermometer, but the estimates for artificial cerebrospinal fluid were 1.04°C lower. After correcting for this systematic difference, the estimated temperature within the lateral ventricles of volunteers was 39.9°C. Using diffusion directions less sensitive to cerebrospinal fluid flow, it was 37.7°C, which was in agreement with the literature. Conclusion:, Although further improvements are needed, measuring the temperature within the lateral ventricles using diffusion MRI is a viable method that may be useful for clinical applications. We introduced the method, identified sources of error and offered remedies for each. [source] Clinical characteristics and outcome of current standard management of central retinal artery occlusionCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2010Adam K Rudkin BMBS Abstract Background:, To investigate the visual outcomes in acute central retinal artery occlusion (CRAO) with current standard therapy at two university teaching hospitals. Methods:, Retrospective analysis of two cohorts of CRAO patients from John Hopkins Hospital (JHH; USA), and Flinders Medical Centre (FMC; Australia), treated with current standard therapy. The outcome measures were visual acuity, and subsequent ocular and systemic ischaemic events. Results:, The mean follow-up period was 11.2 ± 13.1 months in the JHH cohort and 35.4 ± 34.9 months in the FMC cohort. The frequency distribution of vascular risk factors and the incidence of subsequent ischaemic events were similar for the patients from both institutions. All patients from JHH were treated as inpatients, whereas 79% of patients from FMC were treated as outpatients. More patients in the JHH cohort underwent paracentesis, ocular massage or were treated with intraocular hypotensive agents (76%) than in the FMC cohort (26%); however, there was no significant difference in visual outcome between the two cohorts (P = 0.114). Conclusion:, Despite differences in management of CRAO between two institutions in different countries, visual outcomes were similar. This suggests a lack of efficacy of current standard treatment in acute CRAO. [source] | |||||||||||||||||||||||||