NOAF occurred in 44 patients at a median time of 48 hours following TAVI, and its incidence was increased in patients with larger left atrial size and those undergoing transapical TAVI.  Up to 40% of the NOAF episodes occurred either during or within the 24 h following the procedure (figure 1).  NOAF was associated with a higher rate of stroke/systemic embolism, but not a higher mortality, at 30 days and at 1-year follow-up.

Figure 1. Timing of first atrial fibrillation (AF) episodes following transcatheter aortic valve implantation in 44 patients with new-onset AF. Adapted from original

Figure 2. Duration of new-onset atrial fibrillation episodes following transcatheter aortic valve implantation. Adapted from original

The authors say the increase in cardioembolic events associated with NOAF offers an  “important new insight into the mechanisms of cerebrovascular events following TAVI. Indeed, some…events seemed to be related to the no initiation of anticoagulant therapy upon documentation of the AF episode, which further emphasizes the clinical relevance of optimizing antithrombotic treatment in this high-risk subset of patients”.

They add that “future studies will have to determine the potential usefulness of implementing preventive strategies to reduce the occurrence of NOAF and its potentially devastating consequences in the setting of TAVI”.

References

1 Amat-Santos IJ, Rodés-Cabau J, Urena M, et al. Incidence, predictive factors, and prognostic value of new-onset atrial fibrillation following transcatheter aortic valve implantation. JACC 2012;59. doi:10.1016/j.jacc.2011.09.061.

The figures showed significant improvements both in the number of new cases of stroke and in subsequent survival.

  The prevalence of stroke rose by 12.5%, but the number of new cases fell by almost a third (30%) over the decade – from 1.48 per 1,000 person years in 1999 to 1.04 in 2008.  

Among those aged 80 and over, who are at the highest risk of stroke, the fall was even greater, at 42%.  

The rate of deaths within 56 days of a first stroke almost halved, falling from one in five (21%) in 1999 to nearly one in 10 (12%) in 2008.

These improvements were paralleled by a consistent rise in prescriptions for preventive drugs, particularly those used to lower cholesterol and high blood pressure, both of which are risk factors for stroke.

  But doctors undertreated patients with AF, the findings showed.

Around one in 10 patients had been diagnosed with AF before their first stroke, and this group were at significantly higher risk of death from stroke than those who did not have AF.

  But only one in four of all those with AF were prescribed preventive anticoagulant treatment, with no sign that more serious AF was being targeted.

Women were significantly more likely to have serious AF than men, but they were less likely to be given anticoagulant therapy. This was prescribed for 29% of men with AF, but only 22% of women.

Both men and women with AF were more likely to be prescribed anticoagulants after a first stroke, but while this rose from 29% to 48% of men, it only rose from 22% to 35% of women.

  The authors conclude that primary care doctors are tackling the risk factors for stroke much more effectively. “However, there is a clear suggestion that risk stratification is not yet optimal, particularly in relation to patients with AF,” they write.

References

1 Lee S, Shafe ACE, Cowie MR.  UK stroke incidence, mortality and cardiovascular risk management 1999-2008: time-trend analysis from the General Practice Research Database. BMJ Open 2011;2:e000269. doi: 10.1136/bmjopen-2011-000269

There are now more than one million strokes per year in Europe. Global predictions indicate that the incidence of fatal stroke (along with heart disease and cancers) will continue to rise, from around 6 million per year in 2010 to almost 8 million per year by 2030.

The European Society of Cardiology emphasises that most of these same risks for stroke are also the major risks for coronary heart disease. Moreover, atrial fibrillation has also been clearly associated with an increased risk of stroke.

Professor Freek Verheugt, from the Onze Lieve Vrouwe Gasthuis in Amsterdam and speaking on behalf of the ESC, says: “Stroke is not an inevitable consequence of ageing, so by identifying and modifying risk factors there are opportunities to reduce the incidence and mortality rate of this devastating condition.”

According to the World Stroke Organization, there are six steps anyone can take to reduce their risk of stroke :

• Know your personal risk factors: high blood pressure, diabetes, and high blood cholesterol.

• Be physically active and exercise regularly.

• Avoid obesity by keeping to a healthy diet.

• Limit your alcohol consumption.

• Avoid cigarette smoke. If you smoke, seek help to stop.

• Learn to recognise the warning signs of a stroke.

The WSO also emphasises the importance of time if any of the warning signs are apparent: a sudden numbness, especially at one side of the body; sudden trouble speaking or seeing; loss of balance or sudden vertigo; and a sudden severe headache with no apparent cause. Any of these signs are a cause for alarm, because, says Professor Verheugt, stroke is a medical emergency and any minutes saved now can make a big difference to survival. “Time lost is brain function lost,” says the WSO. It is also now clear that stroke survivors will do better if they are admitted to dedicated stroke units staffed by multidisciplinary teams. Hospital care, medication, vascular surgery and rehabilitation are the cornerstones of treatment.

ESC Clinical Practice Guidelines on Cardiovascular Disease Prevention, which were updated in 2007, list stroke alongside coronary artery disease, heart failure and peripheral artery disease as cardiovascular diseases within the scope of prevention initiatives. The ESC Clinical Practice Guidelines distinguish between haemorrhagic stroke (around 15% of cases) and ischaemic stroke, but add that the cause of many strokes remains undetermined. The Guidelines note that “antihypertensive treatment reduces risk of both ischaemic and haemorrhagic stroke”, and that “stroke prevention is still the most important effect of antihypertensive treatment”.

The Interstroke study¹, which was reported in 2010 following an analysis of stroke data from 22 countries, indicates that ten risk factors are associated with 90% of the risk of stroke.² The highest attributable effect of individual risk factors was 35% from hypertension, 26.5% for waist-to-hip ratio, and 19% for current smoking.

Moreover, a study of activity in the reduction of stroke risk in almost 50,000 people in Finland (and followed up for almost 20 years) found that “high physical activity” was associated with a lower risk of stroke than low physical activity. Similar reductions in risk were found with “daily active commuting”.²

As defined in the European Heart Health Charter,³ the ESC’s declared targets for cardiovascular health throughout the European Union are :

• Zero smoking

• Three kilometres daily walking

• Five portions of fruit and vegetables per day

• <140/90 mmHg blood pressure

• <5 mmol/l total cholesterol

• <3 mmol/l LDL-cholesterol

• Zero diabetes

References

1 O’Donnell MJ, Xavier D, Liu L, et al. Risk factors for ischaemic and intracerebral haemorrhagic stroke in 22 countries (the INTERSTROKE study): a case-control study. Lancet 2010;376:112–23. (Available at http://media.ne.cision.com/l/uikfxxvg/www.lancet.com/journals/lancet/article/PIIS0140-6736%2810%2960834-3/abstract)

2 Hu G, Sarti C, Jousilahti P, et al. Leisure time, occupational, and commuting physical activity and the risk of stroke. Stroke 2005;36:1994–9.

3 European Heart Health Charter, European Society of Cardiology (Available at: http://media.ne.cision.com/l/uikfxxvg/www.escardio.org/about/what/advocacy/Pages/health-charter.aspx)

A single therapeutic antibody injection in mice was found sufficient by Schwaeble and colleagues to produce significantly smaller infarct volumes than were found in another group, suggesting the therapeutic effects of MASP-2 inhibition and the utility of anti–MASP-2 antibody therapy in reperfusion injury and other lectin pathway-mediated disorders.

“This is a fascinating new achievement in the search for novel treatments to significantly reduce the tissue damage and impaired organ function that occur following ischaemia in widespread and serious conditions such as heart attacks and strokes,” said Professor Schwaeble. “This new potential therapy was also shown in animals to significantly improve outcomes of transplant surgery and may be applicable to any surgical procedure where tissue viability is at risk due to temporary interruption of blood flow”.

The University of Leicester team has been working with Omeros Corporation in Seattle, which holds exclusive worldwide intellectual property rights to the MASP-2 protein, all therapeutic antibodies targeting MASP-2 and all methods for treating complement-mediated disorders by inhibiting MASP-2. It is anticipated that the first clinical trials evaluating Omeros’ human antibody in MI patients will be conducted in the Leicester Biomedical Research Unit, Glenfield Hospital, Leicester.

References

1 Schwaeblea WJ, Lyncha NJ, Clark JE, et al. Targeting of mannan-binding lectin-associated serine protease-2 (Masp2) confers a significant degree of protection from myocardial and gastrointestinal ischemia/reperfusion injury. Proceedings of the National Academy of Sciences of the United States of America 2011; doi: 10.1073/pnas.110174810

The impact of inhaling smoke second hand is shown by the results of a study[3] which examined 1,218 nonsmokers, aged 50 and over, who participated in the Swiss Cohort Study on Air Pollution and Lung Disease in Adults (2001-2003). Those exposed to secondhand smoke for more than 2 hours a day had lower heart-rate variability and a 2.7% higher heart rate (95% CI, -0.01 to 5.34%) than those not exposed.

The capacity of second-hand smoke to increase the danger of stroke in those susceptible is the subject of a mounting scientific consensus. In 2006 the American Heart Association’s guidelines for the prevention of stroke[4], as well as highlighting smoking itself as a high risk factor, cited “growing evidence that exposure to environmental tobacco smoke (or passive smoke) increases the risk of cardiovascular disease, including stroke” (p.583).

The document identified the damaging effects of smoking as involving changes in blood dynamics and vascular stenosis. Asserting that the impact of secondhand smoke constitutes a considerable danger in its own right, the guidelines insist that “exposure to environmental smoke needs consideration in overall risk assessment”.

The CDC-commissioned report takes full advantage of hindsight, surveying the results of the widespread and increasingly severe restrictions placed on smoking in Europe and the United States over the last decade. The committee has compiled numerous studies which correlate a reduction in local hospital admissions for acute coronary events with the enforcement of anti-smoking legislation in various locations.

The text also provides a comprehensive history of the past research which has informed this debate, drawing on the body of evidence it has provided to echo and amplify the scientific consensus that there exists a causal link between secondhand smoke inhalation and cardiovascular disease.

References

1. Goldman et al, Secondhand Smoke Exposure and Cardiovascular Effects: Making Sense of the Evidence, Goldman et al, (The National Academies Press, 2010)
2. Haass, M., and W. Kubler. 1997. Nicotine and sympathetic neurotransmission (Cardiovascular Drugs and Therapy 10(6):657-665, 1997)
3. Dietrich, D. F., et al, Effects of passive smoking on heart rate variability, heart rate and blood pressure: An observational study (International Journal of Epidemiology 26(4):834-840, 2007)
4. Sacco et al, Guidelines for Prevention of Stroke in Patients With Ischemic Stroke or Transient Ischemic Attack: A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association Council on Stroke (Stroke;37;577-617, 2006)

• To ensure that primary healthcare professionals (predominantly GPs and practice nurses) are screening, diagnosing and treating AF to optimum levels.
• To raise awareness of AF as a risk factor for stroke amongst the public.
• To lobby national policy makers for improvement in and better implementation of guidance around AF detection/treatment.

Efforts will also include an organised advertising campaign on the dangers of AF, targeting the public, and a parliamentary reception in June to spread awareness amongst and gain support from policymakers. The Stroke Association has also carried out a survey of 1000 GPs to gauge clinical awareness levels of the link between the two conditions, and to ascertain their concerns over the current diagnosis, treatment and management of AF – the results will be published early in the new year.

The Stroke Association’s planned campaign will follow on the heels of a report it published recently with the Atrial Fibrillation Association[1] analysing widespread weaknesses in management of the AF/stroke problem. Their report highlights the general under-diagnosis and under-treatment of AF by clinicians, as well as the scant attention given to it by policymakers.

Its authors suggest that despite the dangers and great economic toll of the condition, AF rarely attracts the attention its severity and epidemiology warrants. Based on the results of a clinician survey, they claim that “clinicians do not regard AF as especially life threatening”, despite the immediate, well-recognised dangers posed by stroke itself, indicating that clinicians “may not fully appreciate the strength of the association between stroke and AF” [1] (p.15).

The report refers to a survey conducted by the AF Aware group[2] which found that 31% of UK patients with AF had never seen a cardiologist, a further 24% saw their cardiologist less than once a year, and 35% of patients only saw their GP once a year or less. The report’s authors recommend more thorough scrutiny in AF care, including specialist nurses and clinics for dedicated treatment.

It also evaluates the presence of AF within the NHS’ Quality and Outcomes Framework (QOF) for GPs, stating the need for greater encouragement of monitoring and treatment. The QOF currently rewards practices for producing a register of AF patients and for the percentages, firstly, diagnosed by ECG or a specialist and, secondly, treated with anticoagulants or anti-platelet therapy. However, the report’s authors point out that QOF indicators do not encourage active identification of AF in patients with associated risk factors, such as age or obesity, who may benefit from additional treatment to anticoagulation alone.

The Stroke Association, in collaboration with Stroke Alliance for Europe (SAFE), Atrial Fibrillation Association (AFA) and Sanofi-Aventis, have commissioned two research studies around AF in the past two years. Initially, the Sanofi-sponsored ‘AF Aware’ campaign was launched to highlight differences in information provision for AF patients in Europe. Patients were surveyed about their treatment and the amount and quality of information about AF they were offered, the results of which were then compared with the perceptions of AF healthcare professionals.[3]

As a result of the survey, SAFE and The Stroke Association obtained a larger grant from Sanofi to commission a health economics based study in 2010 about the provision of AF services across Europe, and how they compared, with a particular emphasis on Eastern Europe. The results from this study were very recently presented to the SAFE annual conference in Slovenia. They are also planning further research commissions around AF in 2011, and are currently beginning the process of identifying further gaps and areas of AF research needing further study on a Europe-wide basis.

According to Dr Peter Coleman, Deputy Director of Research, the Association is particularly interested in recent Lancet publications from Professor Peter Rothwell[4, 5, 6, 7] and colleagues in Oxford, who have shown in the OXVASC cohort that patients exhibiting significant variability in their blood pressure may be at significantly higher risk of stroke than patients who have stable hypertension, and that certain blood pressure medications actually promote and increase blood pressure variability. Coleman tells Arrhythmia Watch that the findings “are particularly applicable to people suffering from AF, as it may be that individuals suffering the combination of variable blood pressure and AF could be hugely at risk of stroke”.

The Association also recognises that the fast and reliable diagnosis of AF is a key area for future developments, and have had recent talks with a medical devices manufacturer regarding their wearable ECG monitors. The Stroke Association carries out regular testing of the public in their ‘Know Your Blood Pressure’ campaign, emphasising the importance of getting any palpitations checked by a healthcare professional, but appreciate that infrequent blood pressure monitoring and ECG is unlikely to pick up idiosyncratic AF and that a more focused intervention is required in people who suspect they have AF.

References

1. ‘Keeping Our Finger on the Pulse: Why Wales Must Address the Personal, Clinical and Economic Impact of Atrial Fibrillation’, Atrial Fibrillation Association & Stroke Association in Wales (2010) http://www.stroke.org.uk/media_centre/press_releases/wales/keeping_our_finger.html
2. Close the Gap, AF Aware survey (2009)
3. An international survey of physician and patient understanding, perception, and attitudes to atrial fibrillation and its contribution to cardiovascular disease morbidity and mortality, European Society of Cardiology (2009)
4. Blood pressure variability and risk of new-onset atrial fibrillation: a systematic review of randomized trials of antihypertensive drugs, Webb AJ, Rothwell PM., (Stroke. 2010 Sep;41(9):2091-3. Epub 2010 Jul 22)
5. Effects of beta blockers and calcium-channel blockers on within-individual variability in blood pressure and risk of stroke, Rothwell PM, Howard SC, Dolan E, O’Brien E, Dobson JE, Dahlöf B, Poulter NR, Sever PS; ASCOT-BPLA and MRC Trial Investigators, (Lancet Neurol. 2010 May;9(5):469-80. Epub 2010 Mar 11)
6. Effects of antihypertensive-drug class on interindividual variation in blood pressure and risk of stroke: a systematic review and meta-analysis, Webb AJ, Fischer U, Mehta Z, Rothwell PM., (Lancet. 2010 Mar 13;375(9718):906-15)
7. Prognostic significance of visit-to-visit variability, maximum systolic blood pressure, and episodic hypertension, Rothwell PM, Howard SC, Dolan E, O’Brien E, Dobson JE, Dahlöf B, Sever PS, Poulter NR., (Lancet. 2010 Mar 13;375(9718):895-905)

Anticoagulants can reduce the risk of stroke by up to 80% here,“ says  Prof. Einhäupl. New substances such as dabigatran and rivaroxaban which can be taken orally, and overcome the need for INR monitoring, should make life easier for doctors and patients once they are approved, in his view.

Fewer side effects  – equal effectiveness

The effects of dabigatran were tested in the  RE-LY study on 18,000 participants, and its findings were discussed at the neurology congress in Berlin. “In general, the substance proved to be well tolerated. With the same efficacy, dabigatran had fewer side effects, and with higher efficacy approximately the same side effects as standard drugs,“ says Prof. Einhäupl. However it is too early for euphoria. „”We still don’t know enough about the long term effects of the drugs. Dabigatran has yet to be approved and is expected to be on the market by year’s end. The effects of  rivaroxaban are now being tested on patients with atrial fibrillation. There is of course always some level of risk „that a patient becomes a ‘bleeder’ as a result of the drugs,“  says Prof. Einhäupl. „Each individual case must be carefully weighed up. But as soon as an additional risk factor arises, when atrial fibrillation is already present, these measures should be employed.“ Among patients at risk are those over 60, diabetics and heavy smokers.

Stroke prevention through rhythm control in AF

A new antiarrhythmic drug (dronedarone) could be of great importance in future in treating atrial fibrillation. A major international study (ATHENA) demonstrated that stroke risk was reduced relatively by 34%. Because stroke was not the primary objective of the study, further investigations are now necessary to confirm this surprising result. „And the mechanisms by which this effect is achieved are still unclear,“ says Prof. Einhäupl. The lower rate of side effects observed, compared to the precursor chemical amiodarone, is also a benefit.

Secondary prevention in stroke patients

Further study results on the theme of operative secondary prevention of stroke were also presented. The German Stroke Society compared carotid endarterectomy with the insertion of stents in the carotid artery. Our suspicions were confirmed. Stent implantation offers no advantage over a well conducted carotid operation, but probably carries disadvantages,“ says Prof. Einhäupl. “The mortality risk or the risk of a further stroke are  marginally higher for patients with stents. “I would then, other than in a  few exceptions, always give preference to a well conducted carotid operation“, he said.

Longer therapeutic window for thrombolysis

Studies on thrombolysis presented at the neurology congress also demonstrate improved prospects for stroke victims. Medical guidelines until now have stipulated that thrombolysis should be carried out only within three hours of a stroke. “For this reason, and others, this treatment has been available to only a few patients,“ says Prof. Einhäupl. A large scale European study has now demonstrated that thrombolysis can be used safely and effectively up to four and a half hours later.

Experience at the Berlin Charité has shown that comprehensive rapidly conducted MRI examinations on acute stroke patients can offer new treatment options. In the course of clinical observation of 11 stroke patients with ischaemia, after MRI examination thrombolysis was safely conducted. This was done although it was unclear when the patient had suffered the stroke. “The results show that those patients in whom the course of the stroke is unclear can also receive  thrombolysis. The precondition is that the decision be made on the basis of precise MRT results,“ says Prof. Einhäupl. Further examinations show that thrombolysis can also be carried out on patients with acute stroke but mild symptoms.

“This study provides excellent ammunition both to convince patients about the benefits of reducing their individual salt intakes and also to persuade the EU of the urgent need to introduce legislation to restrict the salt content of  processed foods,” said ESC spokesman Professor Frank Ruschitzka, a cardiologist and hypertension specialist from the University of Zurich, Switzerland.

“This study represents the evidence that a reduction of salt intake not only lowers blood pressure but also prevents cardiovascular events. The case for population-wide salt reduction is now compelling,” he added.

In the paper, Kirsten Bibbins-Domingo and colleagues, from the University of California, San Francisco, USA, undertook a computer simulation showing the effects of population wide reductions of dietary salt intakes in all adults aged 35 to 85 years in the USA.   Reducing  dietary salt intake by 3 g per day (1200mg less sodium per day) could result in 60,000 to 120,000 fewer cases of heart disease , 32,000 to 66,000 fewer strokes and 54,000 to 100,000  fewer heart attacks.

A reduction in dietary salt of 3g per day, the authors went on to say, would have approximately the same effect on reducing cardiac events as a 50 % reduction in tobacco use, a 5% reduction in body mass index among obese adults or the use of statins to treat people at low or intermediate risk for CHD events.  Furthermore, reducing dietary salt intakes by 3g per day would save  $10 billion to $ 24 billion in annual health care costs.

ESC spokesperson Professor Giuseppe Mancia,  from the University of Milano-Bicocca, St. Gerardo Hospital (Milan, Italy), said the annual health cost savings outlined in the study would be likely to prove a persuasive argument for both the EU and individual European governments.

Recent studies clearly show that salt reduction reduces cardiovascular deaths.⁴ Epidemiological studies have also firmly established that increased intakes of salt directly increase blood pressure.  High salt intakes are believed to exert their detrimental effects by influencing fluid retention, which in turn increases blood pressure. “But it’s important for patients to appreciate that not all cardiovascular problems relating to salt are mediated through hypertension. Salt can have an adverse effect on cardiovascular health, even among people with normal blood pressure,” said Ruschitzka.

Salt intakes across Europe are known to vary widely, ranging from 8.6 g of salt per day  in the UK, to around 12 g salt in Croatia. Even the best intakes, however, are falling  widely short of the  ESC Clinical Practice Guidelines for the Management of Arterial Hypertension (2) , based on WHO data, that recommend that only 5g of salt should be consumed  per day. This amounts to just one teaspoonful.

While individuals may use salt sparingly at home, around 75 % of the salt we eat is already in the food we buy. This, says the ESC, underlines the need for legislation to lay down guidelines. “The reality of international food production in Europe means that such public health initiatives need to be tackled on a European wide basis, rather than an individual country basis,” said Ruschitzka.

Furthermore, added Mancia, concerted action is usually more effective. “It has the advantage of preventing country to country inequalities and furthermore prevents the reinvention of the wheel in each individual country,” he said.

But calls for legislation do not mean that physicians should stop their efforts to  persuade patients to introduce individual changes in lifestyle. Patients, they stress, need to be taught about the importance of reducing salt in their cooking and also for the need to check food labels. People need to learn to appreciate that the salt contents can vary widely even in the same product. Take bread, for example. Recent research from Consensus Action on Salt and Health (CASH, a charity lobbying food manufacturers in the UK) has shown that the highest salt content was 3g salt per 100 g of bread, while the lowest was 0.7 g salt per 100g.

To improve cardiovascular health, salt reduction cannot be undertaken in isolation. “It needs to be remembered that lifestyle measures such as smoking cessation, weight reduction, increased physical exercise, and eating plenty of fruit and vegetables are also important for reducing cardiovascular disease,” said Mancia.

Salt was again on the agenda with World Salt Awareness Week 2010 , (February 1- 7) (3).  The week was run by World Action on Salt and Health (WASH), a global group that works with governments  to highlight the need for widespread introduction of population based salt reduction strategies.

Much can be done to reduce salt intakes through public health policy, say WASH.  They cite the success of Consensus Action on Salt and Health (CASH),  launched in 1996 to encourage  food manufacturing companies in the UK to make voluntary reductions in their  salt content. Since the start of the policy salt intakes among UK adults (calculated from 24-hour urine samples) have fallen from 9.5 to 8.6 g per day.

In July 2009, WASH surveyed over 260 food products available around the world from food manufacturers such as KFC, McDonalds, Kellogg’s, Nestle, Burger King and Subway, finding surprisingly wide spread variations. For example, Kellogg’s All Bran for sale in France, Norway, Sweden and the Netherlands contains 1.30 g salt per 100 g compared to salt levels of 0.65 g per 100g for the product in the US. Such data underlines the urgent need to eradicate country to country inequalities, and bring everyone up to the highest possible standards.

“The paper by Bibbins-Domingo and colleagues is an urgent call to action. Policy makers in the European Community need to implement public health interventions that result in reductions in salt intake now. Reducing the salt content of our unneccesarily oversalted ,processed food is an inexpensive, yet highly effective public health intervention that we can’t afford to miss,“ concluded Ruschitzka.

References

1. Bibbins-Domingo K, Glenn CC, Coxson PG et al. Projected Effect of Dietary Salt Reductions on Future Cardiovascular Disease.  New Engl J Med. 2010 published on line on 20 January 2010 (10.1056/NEJMoa0907355)
2. http://www.escardio.org/guidelines-surveys/esc-guidelines/Pages/arterial-hypertension.aspx
3. www.worldactiononsalt.com
4. Pasquale Strazzullo, Lanfranco D’Elia, Ngianga-Bakwin Kandala, and Francesco P Cappuccio.  Salt intake, stroke, and cardiovascular disease: meta-analysis of prospective studies. BMJ 2009;339:b4567, doi: 10.1136/bmj.b4567 (Published 24 November 2009)

Physicians are often hesitant to refer patients with CKD to undergo carotid endarterectomy—because these patients have a high risk of complications and death after undergoing invasive surgeries.

Drs Amit Garg and Anna Mathew, MD (Lawson Health Research Institute and The University of Western Ontario, Canada), and their colleagues wondered about the role of surgery in preventing strokes in CKD patients. They analyzed data from the North American Symptomatic Carotid Endarterectomy Trial (NASCET), and found that carotid endarterectomy dramatically reduces a CKD patient’s risk of future strokes. Dr. Garg, Dr. Mathew, and colleagues examined the benefits and risks of carotid endarterectomy in CKD patients by analyzing the NASCET kidney function data (gathered during the course of the trial but unpublished). They examined information from 524 CKD patients and compared it with information from 966 individuals with normal kidney function.

The analysis revealed that when patients with mild to moderate CKD underwent carotid endarterectomy, their risk of stroke was greatly reduced while their risk of death was not increased. The risk of experiencing a stroke over a two-year period was reduced by 82%.

“We hope the results of our important study inform physicians about the appropriateness of carotid endarterectomy surgery for their patients with kidney disease,” said Dr. Garg.

Reference

1. “Benefit of Carotid Endarterectomy in Patients with Chronic Kidney Disease,”  appears online at http://jasn.asnjournals.org/ from December 10, 2009, doi 10.1681/ASN.2009030287.

The Report warns of a stroke epidemic across Europe, if actions are not taken now to slow the rising tide of preventable strokes occurring every year (Table 1). Linda McAvan, Member of the European Parliament (MEP), commented, “It is important that government and healthcare policy makers take action to address the unmet medical needs in stroke prevention. I support the recommendations made in the Report by Action for Stroke Prevention, and believe that their implementation will contribute to the prevention of stroke in patients with AF and, in turn, reduce the dramatically increasing clinical, economic and social burden of stroke in Europe.”

Table 1. Atrial fibrillation and stroke risk in Europe

• A report launched today by experts from medical and patient communities calls on Europe’s policy makers to take urgent action against preventable strokes that strike thousands of atrial fibrillation (AF) patients each year
• Affecting over six million people in Europe , AF, the most common, sustained abnormal heart rhythm, increases the risk of stroke five-fold and is responsible for 15-20% of all strokes caused by blood clots (ischaemic stroke)2,
• The consequences of stroke can devastate not only a patient’s quality of life , but also that of families and carers
• The economic burden of stroke on the European economy is estimated at a staggering €38 billion per annum
• The impact of stroke is predicted to rise dramatically as the number of individuals affected by AF is expected to increase 2.5 fold by 2050 , due to an ageing population7 and improved survival of patients with conditions which predispose AF (e.g.myocardial infarction)
• Many AF-related strokes could be prevented by earlier detection and improved treatment of AF

Recommendations made by the Report include: improving patient education, AF diagnosis and stroke risk assessment, taking new approaches to prevention, facilitating the exchange of best practice between Member States, developing strategies to support adherence to guidelines, and the provision of equal and adequate administration of therapy for patients with AF.

Unmet medical need to prevent stroke in atrial fibrillation patients

“It is clear that there is an unmet medical need for stroke prevention in atrial fibrillation patients,” said Professor Gregory Lip, Professor of Cardiovascular Medicine, from the University of Birmingham Centre for Cardiovascular Sciences, City Hospital Birmingham, UK. “The majority of such strokes are preventable but the under-diagnosis and poor management of AF patients, as well as suboptimal use of anticoagulation and side-effects of current treatments, mean that an unnecessary and heavy burden is placed on patients, their families and carers, as well as our healthcare systems.”

Stroke is the most common cardiovascular disorder after heart disease. Current trends predict that the number of strokes in the EU will rise from 1.1 million per year in 2000 to 1.5 million per year by 2025. Furthermore, AF related strokes are more severe, cause greater disability and have a worse outcome than strokes in patients without AF. People who have a stroke caused by AF are more likely to remain in hospital for longer, are less likely to be discharged to their home and are 50% more likely to remain disabled³.

“The impact of the physical, emotional and cognitive disability on patients following a stroke can be considerable,” said Eve Knight, CEO, AntiCoagulation Europe. “In turn, this can also have a profound impact on the quality of life for the carer and family, who can suffer emotional problems such as depression and anxiety.”

The impact of stroke also stretches our healthcare systems. The economic burden it creates accounts for 2-3% of total healthcare expenditure in the European Union6. Healthcare costs associated with stroke are higher for patients with AF than for patients without AF. AF is a strong independent risk factor for stroke and accounts for 15-20% of all ischaemic strokes (strokes caused by blood clots)^2,3.

The number of people suffering from AF is around six million in Europe alone¹. People with AF are an important target population for reducing the overall burden of stroke, which has been identified by the Heart Health Charter and European Union policy as a key need in Europe.

About AF and stroke

AF is the most common, sustained abnormal heart rhythm1. It causes the two upper chambers of the heart (the atria) to quiver instead of beating effectively, resulting in blood not being completely pumped out, which in turn causes pooling and can lead to clotting in the atria. If a blood clot leaves the atria, it can become lodged in an artery in the brain blocking the blood supply and causing the patient to suffer from an ischaemic stroke . Approximately one in five ischaemic strokes are due to AF³.

AF-related strokes are more severe, cause greater disability and have a worse prognosis than strokes in patients without AF³. Although the current treatment for stroke–vitamin K antagonists such as warfarin–can be effective, they are also associated with a number of drawbacks and are currently underused in Europe, especially in elderly patients at greatest risk of stroke .

Preventing AF in patients at risk of arrhythmia, diagnosing AF before the first stroke occurs and following recommendations regarding the use of anticoagulation therapies, including potential new treatment options, are critical for effective prevention of AF-related strokes¹⁰.

About the Report

The authors are global leaders in cardiology, neurology, health economics, policy and patient advocacy.

The Report’s call to action and recommendations are endorsed by:

• ADKA (The German Society of Hospital Pharmacists)
• AntiCoagulation Europe (ACE)
• Arrhythmia Alliance (A-A)
• Atrial Fibrillation Association (AFA)
• European Society of Cardiology (ESC) Working Group on Thrombosis
• European Association of Hospital Pharmacists (EAHP)
• European Brain Council (EBC)
• European Heart Rhythm Association (EHRA)
• European Primary Care Cardiovascular Society (EPCCS)
• European Stroke Organisation (ESO)
• European Stroke Conference
• German Competence Network on Atrial Fibrillation (AFNET)
• International Council of Nurses (ICN)
• Italian Atherosclerosis, Thrombosis and Vascular Biology (ATBV) Working Group
• Sociedad Española de Neurologia (Spanish Neurological Association)
• StopAfib.org
• World Stroke Organization (WSO)

The Action for Stroke Prevention alliance is financially supported by Bayer Schering Pharma AG.

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