Epileptic seizures after a first stroke: the Oxfordshire Community Stroke Project.

OBJECTIVE: To describe the immediate and long term risk of epileptic seizures after a first ever stroke. DESIGN: Cohort study following up stroke survivors for 2 to 6.5 years; comparison with age specific incidence rates of epileptic seizures in the general population. SETTING: Community based stroke register. SUBJECTS: 675 patients with a first stroke, followed up for a minimum of 2 years. MAIN OUTCOME MEASURES: Occurrence of single and recurrent seizures. RESULTS: 52 patients had one or more post stroke seizures; in 25 the seizures were recurrent. The 5 year actuarial risk of a post stroke seizure in survivors (excluding 19 patients with a history of epilepsy and 3 patients in whom the seizure occurred shortly before death from another cause) was 11.5% (95% confidence interval 4.8% to 18.2%). The relative risk of seizures, in comparison with the general population, was estimated at 35.2 in the first year after stroke and 19.0 in year 2. The risk of seizures was increased in survivors of subarachnoid and intracerebral haemorrhage (hazard ratio for intracranial haemorrhage v cerebral infarction 10.2 (3.7 to 27.9)). The risk of seizures after ischaemic stroke was substantial only in patients presenting with severe strokes due to total anterior circulation infarction. Only 9 of 295 patients (3%) independent one month after stroke suffered a seizure between 1 month and 5 years (actuarial risk 4.2% (0.1% to 8.3%)). CONCLUSION: Stroke patients have about an 11.5% risk of single or recurrent seizures in the first 5 years after a stroke. Patients with more severe strokes or haemorrhagic strokes are at higher risk.     

Incidence of stroke in Oxfordshire: first year's experience of a community stroke register.

The Oxfordshire Community Stroke Project is a prospective study of all new cases of stroke and transient ischaemic attack in a defined population of about 103 000 patients registered with 49 general practitioners; every case is assessed by a neurologist and most patients undergo a CT scan or are examined post mortem, or both, to ensure accurate diagnosis. Out of 404 cases registered in the first year, 168 patients had suffered a first stroke, 52 a recurrent stroke, and 41 a transient ischaemic attack; 143 were excluded. Of the 168 patients with their first stroke, 153 (91%) were seen by a neurologist and 149 (89%) had a CT scan or came to necropsy. The pathological diagnosis was cerebral infarction in 127 cases (76%), intracranial haemorrhage in 22 (13%), and unknown in 19 (11%). The estimated yearly incidence of first stroke was 1.95/1000 population (age adjusted to 1981 population of England and Wales).     

Diurnal variation in incidence of stroke: Oxfordshire community stroke project.

OBJECTIVE--To determine whether diurnal variation occurs in the onset of stroke. DESIGN--Community based study over four years. SETTING--Oxfordshire, United Kingdom. SUBJECTS--105,000 people, of whom 675 had a first ever stroke. 545 had a cerebral infarction, 66 had primary intracerebral haemorrhage, 33 had subarachnoid haemorrhage, and in 31 the type of stroke was not known. MAIN OUTCOME MEASURES--Time of stroke and degree of activity at onset. RESULTS--In the 578 patients for whom it was known whether onset occurred while asleep or awake, the proportion with onset during sleep was 25% (135/545) for cerebral infarction, 17% (11/66) for primary intracerebral haemorrhage, and 0% (0/33) for subarachnoid haemorrhage. This difference persisted if patients in whom it was not known whether they were asleep or awake at onset were classed as asleep. For all stroke types together there was a significant (chi 2 = 218.7, p less than 0.001) diurnal variation with a morning peak between 0800 and 1000, which persisted even after allowing for strokes first noted on waking by redistributing the hour of onset through the preceding eight hours (chi 2 = 47, p less than 0.001). A significant diurnal variation was also found in the onset of cerebral infarction (peak 0800-1000, chi 2 = 208.4, p less than 0.001). Fewer patients had other forms of stroke and the diurnal variations for primary intracerebral haemorrhage (peak 1000-1200) and subarachnoid haemorrhage (peaks 0800-1000 and 1800-2000) were not significant. There seemed to be a second smaller peak for all types of stroke. CONCLUSIONS--All types of stroke are most likely to occur after waking in the morning. The cause of the circadian variation requires further study.     

Cardioversion and Risk of Adverse Events with Dabigatran versus Warfarin—A Nationwide Cohort Study

Aim

Cardioversion can rapidly and effectively restore sinus rhythm in patients with persistent atrial fibrillation. Since 2011 dabigatran has been available as an alternative to warfarin to prevent thromboembolic events in patients with non-valvular atrial fibrillation undergoing cardioversion. We studied time to cardioversion, risk of adverse events, and risk of readmission with atrial fibrillation after cardioversion according to anticoagulation therapy.

Methods and Results

Through the nationwide Danish registries we included 1,230 oral anticoagulation naïve patients with first time non-valvular atrial fibrillation and first time cardioversion from 2011 to 2012; 37% in the dabigatran group (n = 456), and 63% in the warfarin group (n = 774). Median time to cardioversion was 4.0 (interquartile range [IQR] 2.9 to 6.5) and 6.9 (IQR 3.9 to 12.1) weeks in the dabigatran and warfarin groups respectively, and the adjusted odds ratio of cardioversion within the first 4 weeks was 2.3 (95% confidence interval [CI] 1.7 to 3.1) in favor of dabigatran. The cumulative incidence of composite endpoint of stroke, bleeding or death were 2.0% and 1.0% at 30 weeks in the warfarin and dabigatran groups respectively, with an adjusted hazard ratio of 1.33 (95% CI 0.33 to 5.42). Cumulative incidence of readmission with atrial fibrillation after 30 weeks were 9% and 11% in the warfarin and dabigatran groups, respectively, and an adjusted hazard ratio of 0.66 (95% CI 0.41 to 1.08).

Conclusion

Anticoagulation treatment with dabigatran allows shorter time to cardioversion for atrial fibrillation than warfarin, and appears to be an effective and safe alternative treatment strategy to warfarin.     

Rate-control or rhythm-control: where do we stand?

Atrial fibrillation is the most common sustained rhythm disturbance and its prevalence is increasing worldwide due to the progressive aging of the population. Current guidelines clearly depict the gold standard management of acute symptomatic atrial fibrillation but the best-long term approach for first or recurrent atrial fibrillation is still debated with regard to quality of life, risk of new hospitalizations, and possible disabling complications, such as thromboembolic stroke, major bleeds and death. Some authors propose that regaining sinus rhythm in all cases, thus re-establishing a physiologic cardiac function not requiring a prolonged antithrombotic therapy, avoids the threat of intracranial or extracranial haemorrhages due to Vitamin K antagonists or aspirin. On the contrary, advocates of a rate control approach with an accurate antithrombotic prophylaxis propose that such a strategy may avoid the risk of cardiovascular and non cardiovascular side effects related to antiarrhythmic drugs. This review aims to explore the state of our knowledge in order to summarize evidences and issues that need to be furthermore clarified.     

Cost effectiveness of primary stroke prevention in atrial fibrillation: Swedish national perspective.

OBJECTIVE--To assess the potential effects of primary prevention with anticoagulants or aspirin in atrial fibrillation on Swedish population. DESIGN--Analysis of cost effectiveness based on the following assumptions: about 83,000 people have atrial fibrillation in Sweden, of whom 22,000 would be potential candidates for treatment with anticoagulants and 55,000 for aspirin treatment; the annual 5% stroke rate is reduced by 64% (with anticoagulants) and 25% (with aspirin); incidence of intracranial haemorrhage of 0.3%, 1.3%, or 2.0% per year; direct and indirect costs of a stroke of Kr180,000 and Kr90,000; estimated annual cost of treatment is Kr5030 for anticoagulants and Kr100 for aspirin. SETTING--Total Swedish population. MAIN OUTCOME MEASURES--Direct and indirect costs of stroke saved, number of strokes prevented, and cost of preventive treatment. RESULTS--Depending on the rate of haemorrhagic complications 34 to 83 patients would need to be treated annually with anticoagulants to prevent one stroke; 83 patients would need to be treated with aspirin. Giving anticoagulant treatment only would reduce costs by Kr60 million if the incidence of intracranial haemorrhage were 0.3% but would imply a net expense if the complication rate exceeded 1.3%. The total savings from giving anticoagulant (22,000 patients) and aspirin (55,000 patients) treatment would be Kr175 million per year corresponding to 2 million pounds per million inhabitants each year. CONCLUSIONS--Treatment with anticoagulants and, if contraindications exist, with aspirin is cost effective provided that the risk of serious haemorrhage complications due to anticoagulants is kept low.     

Arterial embolism in thyrotoxicosis with atrial fibrillation.

In 262 patients with thyrotoxicosis and atrial fibrillation there were 26 episodes of arterial embolism (17 cerebral and nine elsewhere) in 21 patients. Twelve incidents occurred with active thyrotoxicosis, three on reversion to sinus rhythm, and 11 after the patients were euthyroid. This important complication is more common than is realised, and most patients should be put on prophylactic anticoagulants when first seen with atrial fibrillation.     

Cooperative study on the value of long term anticoagulation in patients with stroke and non-rheumatic atrial fibrillation

The benefits of long term anticoagulant treatment of patients with non-rheumatic atrial fibrillation and cerebral infarction were studied by comparing two series of patients with stroke from centres with different policies on anticoagulant treatment. The long term prognosis of 50 patients from the Oxfordshire community stroke project, who did not receive anticoagulants, was compared with that of 70 similar patients from Maastricht, who were treated with anticoagulants. After a mean follow up of 27 months there was no significant difference in either the rate of survival or the rate of recurrent stroke between the two groups.These data suggest that any benefit of anticoagulation is modest. A large randomised trial is planned to establish whether long term anticoagulant treatment is of value and, if so, to what extent.     

Value of computed tomography in patients with stroke: Oxfordshire Community Stroke Project.

The usefulness of computed tomography (CT) was assessed in 325 consecutive patients with a "clinically definite first stroke" from a community stroke register. CT detected five "non-stroke" lesions (two cerebral gliomas, one cerebral metastasis, and two subdural haematomas), a frequency of 1.5%. Five patients were identified with cerebellar haemorrhage, but only one survived long enough to have a CT scan. CT was useful in excluding intracranial haemorrhage as the cause of the stroke in four patients receiving anticoagulants and seven receiving antiplatelet treatment; it showed intracranial haemorrhage in one patient taking aspirin. Forty six patients were in atrial fibrillation at the time of their stroke; four had intracranial haemorrhages and three had haemorrhagic cerebral infarcts. Nineteen patients with presumed ischaemic minor stroke were considered suitable for carotid endarterectomy; CT showed small haemorrhages in two. The CT scan provides very useful information in a minority (up to 28%) of patients with first stroke, who can be selected on quite simple criteria: (a) doubt (usually because of an inadequate history) whether the patient has stroke or a treatable intracranial lesion; (b) the possibility of cerebellar haemorrhage or infarction; (c) the exclusion of intracranial haemorrhage in patients who either are already taking or likely to need antihaemostatic drugs or are being considered for carotid endarterectomy; (d) if the patient deteriorates in a fashion atypical of stroke.     

Ablation surgery for atrial fibrillation: "freeze it or buzz it; just do it and cure it"

Patients in normal sinus rhythm have lesser stroke rate, better functional class and quality of life than those in atrial fibrillation. Adding a surgical procedure to cure atrial fibrillation in patients needing correction of structural heart disease has been shown to be a safe option, which benefits the majority in restoration of sinus rhythm. Age is no bar to implement this option. The same does not hold true for lone atrial fibrillation. The affirm trial has shown that there is need for improved treatment strategies for patients in atrial fibrillation, although young patients were not represented in sizable proportion. There is need to develop curative treatment for patients with lone atrial fibrillation. And there are technological advances in the form of ablative energy sources and hardware for applying these with minimal invasion. "Between tomorrow's dream and yesterday's regret is today's opportunity". Let's make the best of it!     

Treatment of Cardiac Arrhythmias with Synchronized Electrical Counter-shock

Synchronized electrical countershock is an intriguing new method for the treatment of ectopic tachycardias. The authors applied this treatment to 20 patients with chronic atrial fibrillation and, in 17 patients, sinus rhythm was restored immediately. An additional four patients with atrial flutter were successfully converted to sinus rhythm. One patient developed a hemiplegia two weeks after cardioversion. No other untoward side effects were observed. In two patients with ventricular fibrillation electrical countershock terminated the arrhythmia. After successful cardioversion of atrial fibrillation, a maintenance dose of quinidine is given to help maintain sinus rhythm. In spite of this precaution, one-half of the patients reverted to atrial fibrillation within a month. The quinidine was administered for two to three days in advance of cardioversion; on this regimen, 10 of 34 patients reverted to sinus rhythm on quinidine alone and did not require countershock. The exact place of this treatment of cardiac arrhythmias has not yet been clearly defined.     

Graves' disease and atrial fibrillation: the case for even higher doses of therapeutic iodine-131.

Seventy five consecutive patients with Graves'' disease complicated by atrial fibrillation were given a large single therapeutic dose of 600 MBq (16.2 mCi) iodine-131 in an effort to control their hyperthyroidism rapidly and thus restore sinus rhythm. Patients were initially followed up every three months after treatment and then at yearly intervals. The mean period of follow up was 3.1 years. A total of 44 of the patients became hypothyroid and 31 euthyroid, and 33 (75%) and 14 (45%) of these patients, respectively, reverted to sinus rhythm (p less than 0.01). Of the 33 who became hypothyroid and reverted to sinus rhythm, 30 had developed the hypothyroidism within six months after treatment. These results are a strong case for increasing the dose of radioiodine in patients with Graves'' disease complicated by atrial fibrillation in an effort to speed the onset of thyroid failure and thus maximise the rate of reversion to sinus rhythm.     

Predictors of early and late stroke following cardiac surgery

Background:

Much is known about the short-term risks of stroke following cardiac surgery. We examined the rate and predictors of long-term stroke in a cohort of patients who underwent cardiac surgery.

Methods:

We obtained linked data for patients who underwent cardiac surgery in the province of Ontario between 1996 and 2006. We analyzed the incidence of stroke and death up to 2 years postoperatively.

Results:

Of 108 711 patients, 1.8% (95% confidence interval [CI] 1.7%–1.9%) had a stroke perioperatively, and 3.6% (95% CI 3.5%–3.7%) had a stroke within the ensuing 2 years. The strongest predictors of both early and late stroke were advanced age (≥ 65 year; adjusted hazard ratio [HR] for all stroke 1.9, 95% CI 1.8–2.0), a history of stroke or transient ischemic attack (adjusted HR 2.1, 95% CI 1.9–2.3), peripheral vascular disease (adjusted HR 1.6, 95% CI 1.5–1.7), combined coronary bypass grafting and valve surgery (adjusted HR 1.7, 95% CI 1.5–1.8) and valve surgery alone (adjusted HR 1.4, 95% CI 1.2–1.5). Preoperative need for dialysis (adjusted odds ratio [OR] 2.1, 95% CI 1.6–2.8) and new-onset postoperative atrial fibrillation (adjusted OR 1.5, 95% CI 1.3–1.6) were predictors of only early stroke. A CHADS₂ score of 2 or higher was associated with an increased risk of stroke or death compared with a score of 0 or 1 (19.9% v. 9.3% among patients with a history of atrial fibrillation, 16.8% v. 7.8% among those with new-onset postoperative atrial fibrillation and 14.8% v. 5.8% among those without this condition).

Interpretation:

Patients who had cardiac surgery were at highest risk of stroke in the early postoperative period and had continued risk over the ensuing 2 years, with similar risk factors over these periods. New-onset postoperative atrial fibrillation was a predictor of only early stroke. The CHADS₂ score predicted stroke risk among patients with and without atrial fibrillation.Stroke remains a devastating complication following cardiac surgery, with substantial functional and economic impact.^1–3 Stroke research in cardiac surgery has focused on the immediate postoperative period;^4–9 however, most patients undergoing cardiac surgery have conditions such as hypertension, diabetes and atrial fibrillation, which place them at long-term risk of stroke.Early and late outcomes among patients undergoing cardiac surgery could be improved if the risk of postoperative stroke was defined and predictors of stroke identified. With this information, clinicians could optimize medical therapy for stroke risk factors such as hypertension,^10,11 improve the evidence-based use of oral anticoagulation in patients with atrial fibrillation and evaluate intraoperative surgical strategies (e.g., removal of the left atrial appendage¹²) in patients whose clinical characteristics predict an increased risk of stroke. We examined the rate and predictors of long-term stroke within 2 years after cardiac surgery.     

慢性心力衰竭合并心房颤动发病的相关机制研究

目的:慢性心力衰竭(Chronic Heart Failure,CHF)是心血管系统常见的疾病,威胁患者的生存周期及生活质量。本研究针对慢性心力衰竭合并房颤的临床特征,进一步探讨其发病机制,为临床治疗提供依据。方法:将80例慢性心力衰竭患者平均分为两组,心律正常的为窦性心律组,伴有心房颤动的作为房颤组。观察并比较两组的左心室射血分数(LVEF)和二尖瓣口舒张期流速(E/A)等心脏功能指标。结果:房颤组左心室射血分数(LVEF)为(0.42±0.08);二尖瓣口舒张期流速(E/A)为(0.65±0.22);左心房内径(LAD)为(53.4±8.2)mm。窦律组左心室射血分数(LVEF)为(0.45±0.09);二尖瓣口舒张期流速(E/A)为(0.72±0.17);左心房内径(LAD)为(46.7±7.9)mm。房颤组患者的LVEF和E/A值均低于窦律组,而LAD则明显高于窦律组,差异具有统计学意义(P0.05)。房颤组醛固酮、血管紧张素(AngII)、脑钠肽(BNP)及超敏C反应蛋白(hs-CRP)均高于窦律组,差异具有统计学意义(P0.05)。结论:慢性心力衰竭合并房颤的发病与患者体内神经内分泌体液系统水平和心脏结构功能有关,具体发病机制需进一步深入研究。     

Predisposing factors for cerebral infarction: the Oxfordshire community stroke project.

The frequency of known causative factors of cerebral infarction was studied in 244 cases of first ever stroke due to cerebral infarction proved by computed tomography or at necropsy who were registered in the first two years of a prospective community based study. Risk factors for cerebral infarction were present in 196 (80%) cases; hypertension in 126 (52%); ischaemic heart disease in 92 (38%); peripheral vascular disease in 60 (25%); a cardiac lesion that was a major potential source of embolism to the brain in 50 (20%); transient ischaemic attacks in 35 (14%); cervical arterial bruit in 33 (14%); and diabetes mellitus in 24 (10%). Thirty one patients (13%) were in atrial fibrillation. Of the 48 patients who were free of risk factors or a major potential cardiac source of embolism at the time of the stroke, 18 were found to have hypertension after the stroke and 10 to have non-atheromatous non-embolic conditions (migrainous cerebral infarction (three), arteritis (two), inflammatory bowel disease (one), arterial trauma (one), autoimmune disease (one), carcinoma of the thyroid (one), and major operation (one). In 20 patients no causative factors could be identified. In this unselected series of patients with first ever stroke due to cerebral infarction most of the strokes were presumed to be due to either atheromatous arterial disease or embolism from the heart, and only 4% (95% confidence interval 2 to 7%) were probably due to non-atheromatous non-embolic causes. This has implications for research into strokes and allocation of public health expenditure.     

Diagnostic value of thyrotrophin releasing hormone tests in elderly patients with atrial fibrillation.

A prospective study was carried out to compare clinical and biochemical thyroid states with responses of thyroid stimulating hormone (TSH) to thyrotrophin releasing hormone (TRH) in elderly patients with either atrial fibrillation (n = 75; mean age (SD) 79.3 (6.0) years) or sinus rhythm (n = 73; mean age 78.4 (5.6) years) admitted consecutively to the department of geriatric medicine. No patient in either group had symptoms or signs of hyperthyroidism. Overall, the TSH responses to TRH did not differ significantly between the two groups. Ten (13%) of the patients with atrial fibrillation (of whom four had raised thyroid hormone concentrations) and five (7%) of the patients with sinus rhythm showed no TSH response to TRH while 26% of each group (20 and 19 patients, respectively) showed a much reduced response. Only one of 13 patients with apparently isolated atrial fibrillation showed no TSH response to TRH, and none of these 13 patients was hyperthyroid. In particular, three patients (two with atrial fibrillation and one with sinus rhythm) who showed no TSH response to TRH at presentation exhibited a return of TSH response to TRH at follow up six weeks later. In conclusion, reduced or absent TSH responses to TRH are common in sick elderly patients whether they have atrial fibrillation or sinus rhythm and whether they are euthyroid or hyperthyroid biochemically. An absence of response is therefore an uncertain marker of hyperthyroidism in these groups of patients, and diagnosis and ablative treatment should be based at least on the presence of raised circulating free triiodothyronine or free thyroxine concentrations, or both.     

46例甲状腺功能亢进性心脏病临床分析

目的：探讨甲状腺功能亢进性心脏病的防治措施。方法：回顾性分析2003年6月至2009年6月收治的46例甲状腺功能抗进性心脏病患者的临床资料。其中男20例,女26例,年龄15-78岁,病程7月-30年;伴心功能衰竭28例（60.9%）,心房纤颤30例（65.2%）,和病态窦房结综合征1例（2.2%）。结果：46例患者均服用甲状腺药物治疗后,甲亢病情缓解,心力衰竭好转。30例心房纤颤患者中,19例恢复窦性心律,剩余11例平均心室率控制在70-100次/min。结论：甲亢性心脏病治疗的关键在于早期诊断,甲亢病情控制后,绝大部分心脏异常可减轻或消失。     

Increased tissue plasminogen activator levels in patients with nonvalvular atrial fibrillation

OBJECTIVE: To determine whether plasma tissue plasminogen activator (tPA) levels (a) are higher in patients with novalvular atrial fibrillation (NVAF) than in control subjects in sinus rhythm; (b) differ between NVAF patients with and without a history of an embolic event (transient ischemic attack or embolic stroke); and (c) differ in control subjects with and without a history of thrombotic stroke. DESIGN: Cross-sectional study. SETTING: Internal medicine outpatient group practice and anticoagulation clinic in 2 teaching hospitals. PATIENTS: Seventy-four NVAF patients (24 with and 50 without a history of an embolic event), separated into 3 groups: no prior embolic event and no warfarin use (group 1), no prior embolic event and warfarin use (group 2), and prior embolic event and warfarin use (group 3). Forty control subjects in sinus rhythm (29 without and 11 with prior thrombotic stroke). OUTCOME MEASURES: Plasma tPA levels. RESULTS: The age-adjusted mean tPA levels exceeded the upper limit of normal in all 3 NVAF groups but not in the control groups. The NVAF patients had significantly higher mean tPA levels than the control subjects (p = 0.015). The levels did not differ significantly between the NVAF patients with a history of an embolic event and those without such a history. The control subjects with a history of thrombotic stroke had significantly higher mean tPA levels than the other control subjects (p = 0.03). CONCLUSIONS: NVAF patients, regardless of their history of embolic events, and control patients with a history of thrombotic stroke have higher tPA levels than subjects in sinus rhythm without a history of stroke. A prospective, longitudinal study involving NVAF patients is required to determine whether high baseline tPA levels are associated with, and perhaps causally related to, an increased risk of stroke.