Saturday, December 30, 2006

 

aspirin plus persantin (dipyridamole)

1: Lancet. 1989 Jul 1;2(8653):1-7. Links
Comment in:
Lancet. 1989 Aug 19;2(8660):443.

Trial of low-dose aspirin plus dipyridamole versus anticoagulants for prevention of aortocoronary vein graft occlusion.

Division of Cardiology, University Hospital, Basel, Switzerland.

In a prospective randomised trial, 249 patients who had aortocoronary vein bypass surgery were assigned either to a platelet inhibitory drug regimen or to standard anticoagulant therapy. Treatment was replaced by placebo in half of the patients in each group after 3 months. The platelet inhibitory drug regimen--very low-dose aspirin combined with dipyridamole--was as effective as standard anticoagulant therapy to prevent early and late graft occlusion. Death, myocardial infarction, and severe bleeding occurred significantly more often in patients receiving anticoagulants, whereas mild drug-related gastrointestinal and cerebral side-effects were more common in patients taking platelet inhibitory drugs. Antithrombotic treatment should be continued for at least 1 year after coronary artery bypass graft surgery.

PMID: 2567792 [PubMed - indexed for MEDLINE]


# posted by roodbont @ 2:58 PM 0 comments
 

as[irin en persantin

1: Eur Heart J. 1994 Aug;15(8):1129-34. Links

Effect of various antithrombotic regimens (aspirin, aspirin plus dipyridamole, anticoagulants) on the functional status of patients and grafts one year after coronary artery bypass grafting.

Department of Cardiology, Academic Medical Centre Amsterdam, The Netherlands.

From 1987 until 1991 a large prospective randomized multicentre study was performed in The Netherlands, Germany and Switzerland entitled CABADAS (Prevention of Coronary Artery Bypass graft occlusion by Aspirin, Dipyridamole, and Acenocoumarol/Phenprocoumon Study). The aim of CABADAS was to evaluate the relative efficacy of (1) aspirin, (2) aspirin plus dipyridamole, and (3) oral anticoagulants in the prevention of vein graft occlusion during the first year after aortocoronary bypass surgery. No significant difference was observed in the incidence of graft occlusion among the three treatment groups. In a subgroup of 127 CABADAS patients, studied in the Academic Medical Centre in Amsterdam, the relationship between treatment and clinical status (i.e. symptoms of angina pectoris and exercise capacity) was assessed, and the relationship between treatment and functional status of the vein grafts was determined by means of thallium-201 exercise scintigraphy. There were no differences in symptoms among the three treatment groups in the 127 patients studied. There were no significant differences either among the treatment groups, as regards exercise capacity and the number or intensity of perfusion defects, in the 81 patients who underwent thallium-201 exercise scintigraphy. The three antithrombotic treatment regimens had a similar effect on the clinical status of patients and on the functional status of venous bypass grafts one year after coronary bypass surgery. This finding underscores the CABADAS results in that aspirin may be the preferred treatment option in patients following venous bypass surgery.

PMID: 7988607 [PubMed - indexed for MEDLINE]


# posted by roodbont @ 2:53 PM 1 comments
 

aspirin en persantin

1: J Am Coll Cardiol. 1994 Nov 1;24(5):1181-8. Links

Effects of low dose aspirin (50 mg/day), low dose aspirin plus dipyridamole, and oral anticoagulant agents after internal mammary artery bypass grafting: patency and clinical outcome at 1 year. CABADAS Research Group of the Interuniversity Cardiology Institute of The Netherlands. Prevention of Coronary Artery Bypass Graft Occlusion by Aspirin, Dipyridamole and Acenocoumarol/Phenprocoumon Study.

Department of Cardiology, University Hospital, Groningen, The Netherlands.

OBJECTIVES. This study was performed to compare the efficacy and safety of aspirin, aspirin plus dipyridamole, and oral anticoagulant agents in the prevention of internal mammary artery graft occlusion. BACKGROUND. Antithrombotic drugs increase vein graft patency after coronary artery bypass surgery. Their benefit after internal mammary artery grafting has not been established. METHODS. Angiographic internal mammary artery graft patency at 1 year was assessed in 494 patients who received both internal mammary artery and vein grafts. These patients were a subgroup of a prospective, randomized vein graft patency study in 948 patients assigned to treatment with aspirin, aspirin plus dipyridamole, or oral anticoagulant agents. The design was double-blind for both aspirin groups and open for oral anticoagulant treatment. Dipyridamole (5 mg/kg body weight per 24 h intravenously, followed by 200 mg twice daily) and oral anticoagulant agents (prothrombin time target range 2.8 to 4.8 international normalized ratio) were started before operation, and low dose aspirin (50 mg/day) after operation. Clinical outcome was assessed by the incidence of myocardial infarction, thrombosis, major bleeding or death. RESULTS. Occlusion rates of distal anastomoses were 4.6% in the aspirin plus dipyridamole group and 6.8% in the oral anticoagulant group versus 5.3% in the aspirin group (p = NS). Overall clinical event rates were 23.3% and 13.3% in the aspirin plus dipyridamole group and the aspirin group, respectively (relative risk 1.75, 95% confidence interval 1.09 to 2.81, p = 0.025), and 17.1% in the oral anticoagulant group. CONCLUSIONS. Internal mammary artery graft patency at 1 year is not improved by aspirin plus dipyridamole or oral anticoagulant agents over that obtained with low dose aspirin alone. However, there is evidence that the overall clinical event rate increases if dipyridamole is added to aspirin.

PMID: 7930237 [PubMed - indexed for MEDLINE]


# posted by roodbont @ 2:48 PM 0 comments
 

combinatie aspirine en persantin

Among patients with recent stroke or transient ischemic attack (TIA), combined therapy with clopidogrel plus aspirin has not been proven better than aspirin alone. But what about dipyridamole plus aspirin? A large trial published in 1996 suggested that this combination was more effective than aspirin alone, but other trials have produced conflicting findings. In the new ESPRIT trial, researchers randomized more than 2700 patients with recent stroke or TIA to receive either aspirin plus dipyridamole (200 mg twice daily) or aspirin alone. No placebo was used. During an average follow-up of 3.5 years, significantly fewer patients assigned to combination therapy than to aspirin alone experienced vascular death, nonfatal stroke, MI, or major bleeding (13% vs. 16%). A meta-analysis of this and five similar dipyridamole-aspirin studies showed an 18% relative risk reduction with combination therapy compared to aspirin alone (Journal Watch Jun 9 2006).

Clopidogrel appears to be a useful adjunct to aspirin therapy in patients with acute coronary ischemia and patients who have undergone percutaneous coronary intervention, but it should not be used with aspirin in other patients at cardiovascular risk. For patients who have had strokes or TIAs, aspirin plus dipyridamole may be the preventive treatment of choice.

— Bruce Soloway, MD

Published in Journal Watch General Medicine December 28, 2006


# posted by roodbont @ 2:33 PM 0 comments

Thursday, December 28, 2006

 

rate and rhythm controle

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Rate vs Rhythm Control

In recent years, physicians have debated whether certain AF patients (eg, those with persistent AF who are older and less symptomatic) are best treated with rate-controlling drugs, such as calcium channel blockers, beta-blockers, and digoxin, or with an approach that aims to restore and maintain sinus rhythm using antiarrhythmic drugs (AADs) and cardioversion. Initially, therapy for AF was guided towards a rhythm-control approach, but the results of the landmark Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM)[11] trial found no significant difference in patient outcomes between the 2 treatment strategies – results that are consistent with the findings of the Pharmacological Intervention in Atrial Fibrillation (PIAF),[12] Strategies of Treatment of Atrial Fibrillation (STAF),[13] and Rate Control vs Electrical Cardioversion for Persistent Atrial Fibrillation (RACE)[14] trials (Table 1).

Table 1. Rate- vs Rhythm-Control Trials

Trial (Year) Patients Studied Results
PIAF[12] (2000) N = 225; persistent AF of 7 to 360 days in duration
  • No difference in symptom improvement
  • Rhythm patients had higher exercise tolerance but significantly higher rate of hospitalizations.
  • Only 23% of patients taking amiodarone were in NSR at follow-up, although 56% of patients who were successfully cardioverted could be maintained in NSR.
  • Amiodarone was discontinued in 25% of the rhythm patients due to drug side effects.
AFFIRM[11] (2002) N = 4060; > 65 years of age or who had other risk factors for stroke or death and had AF that was likely to recur

The study included patients with intermittent self-terminating episodes of AF and those who required cardioversion.
  • At 5-year follow-up, 63% of rhythm patients were in NSR vs 34.6% of rate patients.
  • No significant difference in the rate of death between the 2 groups (23.8% vs 21.3%; P = .08)
  • The number of hospitalizations during follow-up was greater in the rhythm group (P < .001).
  • The stroke rate was low (about 1% per year in both groups); majority of strokes occurred in patients who had stopped taking warfarin or whose INR was subtherapeutic at the time of the stroke.
RACE[14] (2002) N = 522; persistent AF after previous electrical cardioversion; mean age 68 years
  • After mean follow-up of 2.3 years, there was no significant difference in the composite of cardiac death, heart failure, thromboembolic complications, bleeding, implantation of a pacemaker, and severe adverse drug effects.
  • Overall results showed a trend for better outcomes in rate patients (17.2% vs 22.6%).
  • Only 39% of rhythm patients were in NSR, and thromboembolic events were more likely in rhythm patients.
STAF[13] (2003) N = 200; persistent AF; 44.5% were 60-69 years of age and 79% had at least 1 risk factor.
  • No difference in the combination of death, CPR, cerebrovascular event, and systemic embolism after 19.6 mos
  • Rhythm group had significantly more hospitalizations.
  • Rate group showed trend toward higher rate of mortality.
  • Most primary endpoints occurred in AF; only 1 occurred in NSR, shortly after cardioversion.
  • The percentage of patients who were in NSR in the rhythm group after up to 4 cardioversions was 23% at 36 mos.
AF = atrial fibrillation; AFFIRM = Atrial Fibrillation Follow-up Investigation of Rhythm Management; CPR = cardiopulmonary resuscitation; INR = international normalized ratio; NSR = normal sinus rhythm; PIAF = Pharmacological Intervention in Atrial Fibrillation; RACE = Rate Control vs Electrical Cardioversion for Persistent Atrial Fibrillation; STAF = Strategies of Treatment of Atrial Fibrillation

AFFIRM[11] randomized 4060 patients with intermittent (mildly symptomatic) AF and at least 1 risk factor for stroke to a rate-control or rhythm-control strategy. Baseline characteristics were well balanced between the 2 groups; mean age was 69.7 years; and 39.3% and 38.2% of patients had hypertension and coronary artery disease, respectively. In 69.2% of patients, the qualifying episode of AF lasted > 2 minutes and approximately 35% of patients were enrolled following their first episode of AF. At 5-year follow-up, there was no mortality benefit associated with rhythm control (23.8% vs 21.3%; P = .08). However, rhythm-control patients were more likely to be hospitalized than those in the rate-control arm (80.1% vs 73.0%; P < .001), and only 63% of patients in this group were actually able to maintain normal sinus rhythm over the 5-year follow-up. Stroke rates were similar in both rhythm- and rate-control arms (8.9% vs 7.4%; P .93), and strokes occurred most frequently in patients who had stopped their anticoagulation medication altogether or who were on medication but were not adequately anticoagulated (ie, had international normalized ratios [INR] <>

Similar findings were demonstrated in the STAF[13] and RACE[14] randomized studies. However, the results of all of these trials can only be applied to the fairly limited group of patients enrolled -- primarily older AF patients (> 65 years of age) who are mildly symptomatic. Thus, a rate-control strategy may not be the best option for all AF patients, particularly younger patients, those with first-onset AF or poor left ventricular function, or those who are highly symptomatic.



1. Which approach would you use for first-line treatment of your patients with persistent AF?

 Rate control

 Rhythm control

 Ablation
Page 2 of 14

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# posted by roodbont @ 6:39 AM 0 comments
 

atrial fibrilation

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From The American College of Cardiology's Cardiosource
Current Issues in Atrial Fibrillation Management
Posted 12/08/2006
Hein J. J. Wellens, M.D., F.A.C.C.; Sidney C. Smith, Jr., M.D., F.A.C.C.

Abstract and Transcript

Abstract

Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice, accounting for approximately one-third of hospitalizations for cardiac rhythm disturbances. An estimated 2.3 million people in North America and 4.5 million people in the European Union have paroxysmal (self-terminating) or persistent (not self-terminating) AF.1

During the past 20 years, hospital admissions for AF have increased by 66%2 due to the aging of the population, a rising prevalence of chronic heart disease, more frequent diagnosis through use of ambulatory monitoring devices, and other factors.

AF is an extremely expensive public health problem (approximately €3000 [~US $3600] annually per patient)3; the total cost burden approaches €13.5 billion (~US $15.7 billion) in the European Union.

The risk factors for ischemic stroke and systemic embolism in patients with nonvalvular AF are well established (Slide 1). However, while AF is often associated with structural heart disease, a substantial proportion of patients with AF have no detectable heart disease. Hemodynamic impairment and thromboembolic events related to AF result in significant morbidity, mortality, and cost.

In August 2006, the American College of Cardiology (ACC), the American Heart Association (AHA), and the European Society of Cardiology (ESC) published a revision of the 2001 practice guidelines on managing patients with AF.4

The management of this complex and potentially dangerous arrhythmia includes prevention of AF, control of heart rate, prevention of thromboembolism, and conversion to and maintenance of sinus rhythm. The treatment algorithms include pharmacological and nonpharmacological antiarrhythmic approaches, as well as antithrombotic strategies most appropriate for particular clinical conditions.

There are important changes from the 2001 guidelines. The text of the 2006 revision has been reorganized to reflect the implications for patient care, beginning with recognition of AF and its pathogenesis and the general priorities of rate control, prevention of thromboembolism, and methods available for use in selected patients to correct the arrhythmia and maintain normal sinus rhythm.

Advances in catheter-based ablation technologies have been incorporated into expanded sections and recommendations, with the recognition that such vital details as patient selection, optimum catheter positioning, absolute rates of treatment success, and the frequency of complications remain incompletely defined.

Sections on drug therapy have been condensed and confined to human studies with compounds that have been approved for clinical use in North America and/or Europe for pharmacological cardioversion (Slide 2) or maintenance of sinus rhythm (Slide 3) and their recommended doses. There are detailed recommendations, too, relating to antithrombotic therapy in patients with AF (Slide 4).

Accumulating evidence from clinical studies on the emerging role of angiotensin inhibition to reduce the occurrence and complications of AF and information on approaches to the primary prevention of AF are addressed, as these may evolve in the years ahead to form the basis for recommendations affecting patient care.

Finally, data on specific aspects of management of patients who are prone to develop AF in special circumstances have become more robust, allowing formulation of recommendations based on a higher level of evidence than in the first edition of these guidelines.

Overall, the updated guidelines are a consensus document that attempts to reconcile evidence and opinion from both sides of the Atlantic Ocean.

This interview is with Hein Wellens, MD, emeritus professor of cardiology, University of Maastricht. A pioneer in "programmed electrical stimulation of the heart," in the late 1960s he and Rein Schuilenburg, MD, used catheters in a patient with Wolff-Parkinson-White syndrome to locate the origin of the arrhythmia and then a pacing device to initiate and terminate the arrhythmias.

Based on their work, stimulation studies could be combined with analyses of electrocardiograms to provide a noninvasive means of determining the origin of an arrhythmia. This paved the way for new therapeutic approaches, such as antitachycardia pacing, and advances in catheter-based ablation technologies.

The interview was conducted by Sidney C. Smith Jr., MD, FACC, FAHA, FESC, chair of the ACC/AHA Task Force on Practice Guidelines.

Transcripts

Dr. Smith: I am at the 2006 World Congress of Cardiology in Barcelona, Spain. With me is Hein Wellens, professor of cardiology at the University of Maastricht, Netherlands. We're talking about current issues in atrial fibrillation management. Professor Wellens, I've followed your work with great admiration over the years. Can you tell me how you see the field of atrial fibrillation today?

Dr. Wellens: It's a growing problem. The older population is growing and atrial fibrillation is typically a disease that becomes more and more prevalent with age. We have just received the new guidelines for management of atrial fibrillation, and in those guidelines we see - and I am very happy to see this change in emphasis - that the document is concentrating on the individual patient rather than on the electrocardiogram. So many different aspects: rate control versus rhythm control, prevention of thromboembolic situations, how to select antiarrhythmic drug therapy, when is a patient a candidate for catheter ablation of atrial fibrillation? These are very well discussed in the updated guidelines and it's absolutely necessary for any physician looking after a person with atrial fibrillation to read them very, very carefully.

Dr. Smith: I think we ought to point out that these guidelines were produced by the ACC, the European Society of Cardiology, and the American Heart Association. So, they are going to potentially influence the thinking of many cardiologists around the world. What are some of the key changes in the guidelines? Are there any things that are new in terms of patient management?

Dr. Wellens: In recent years, we have read a lot about rate versus rhythm control, and that is one of the aspects of treatment that is very well discussed in the new guidelines. In terms of symptoms, rate control is typically considered for the patient who notices very little of the arrhythmia, while rhythm control is more likely to be applied to the person who notices immediately the arrhythmia and is experiencing consequences of the arrhythmia like shortness of breath, development of heart failure, etc. That's a major point if you are dealing with a patient who is tolerating atrial fibrillation very well; that's a patient for whom you should think about rate control.

Dr. Smith: One of the problems we face frequently with patients is that they have some impairment of ejection fraction - let's say 35% - and they present with new onset atrial fibrillation, they are short of breath, and have some left atrial enlargement. You recognize atrial fibrillation. Do you attempt rate control? Or do you try to go directly to cardioversion? And talk a little here about the remodeling that occurs.

Dr. Wellens: That's a very important point, Sid. As soon as atrial fibrillation occurs, you get electrical changes and contractile changes. The electrical remodeling involves shortening of the refractory period and loss of the relation between heart rate and duration of the refractory period. Also, as you very well know, because of atrial fibrillation the contractile behavior of your atria is lost.

These changes take some time, but they are usually complete after about a week. So the sooner you are able to convert that patient from atrial fibrillation to sinus rhythm the better. It's very important to know that.

Also, pharmacologically, drugs that are able to successfully convert a patient when given within the first 24 hours, like flecainide, no longer work when the arrhythmia has been there for 6 or 7 days. So, the guidelines offer recommendations specific to how long the AF has been present (Slides 5 and 6). Similarly, if you want to convert electrically, the chance that you will be successful is higher when you are able to have that rhythm converted early after the onset of the arrhythmia.

Dr. Smith: Do you move fairly quickly to transesophageal echo? Where do you see the role for that in the time line?

Dr. Wellens: Transesophageal echo is important when you're not sure how long atrial fibrillation has been going on. It's also very important in the patient who has heart disease, because if there is an enlarged atrium, thromboembolic complications are much more common. So, in that situation, esophageal echo is a very important tool.

Dr. Smith: When you make the decision to cardiovert in your practice, do you find more often than not that it's electrical cardioversion? Or do you use drugs in many patients?

Dr. Wellens: You can use drugs if you are able to get the patient on the drug shortly after the onset of the arrhythmia. Like I said, flecainide works well when you give it within the first 24 hours. Other drugs - for example, ibutilide, a class 3 drug - work a little longer so you can still give it 4 or 5 days after the onset of atrial fibrillation. It all depends on the patient you have. Is it a patient who has no cardiac problems apart from the arrhythmia? Or is it a patient who has cardiac disease? What is the time frame from onset of atrial fibrillation to onset of treatment?

Dr. Smith: Let's talk about duration of anticoagulation after cardioversion. Let's say you cardiovert them and they are in normal sinus rhythm. How long do you continue anticoagulation?

Dr. Wellens: That's another important point that's well discussed in the new guidelines. It doesn't make any difference whether you have the paroxysmal form of atrial fibrillation or persistent atrial fibrillation; the risks of thromboembolic complications are similar. So, the duration and incidence of atrial fibrillation are not important in our decision making regarding anticoagulant therapy. That's a very important point.

Dr. Smith: What about the decision to use warfarin versus aspirin? Is this age related? Where do the new guidelines come down on this debate?

Dr. Wellens: Over the years, based on the results of a number of important trials, we have seen a reduction in the number of people we think can be treated with aspirin alone (Slide 7). The new guidelines clearly indicate that you should base the decision on the presence or absence of risk factors. If you have one risk factor, it is possible to put a patient on aspirin, but as soon as you see more risk factors - especially risk factors like a previous stroke or a transient ischemic attack, heart failure, or diabetes - then that patient should be on warfarin.

Dr. Smith: Age should be a consideration at some point too, correct?

Dr. Wellens: Yes, age is also important. If the patient is 75 years or older, you should not put them on anticoagulant therapy unless there is an additional indication, like valve replacement, for example.

Dr. Smith: Very quickly: catheter ablation. What's the role for catheter ablation?

Dr. Wellens: At this point, catheter ablation is very useful in the patient who has no heart disease apart from the arrhythmia and a normal size atrium. The problem is that we don't have long-term data on catheter ablation in sick hearts. That is a major point where we need more data because fibrosis formation is an important player in atrial fibrillation; we don't know how useful catheter ablation is in sick hearts.

Dr. Smith: It's been a real pleasure to have you with us on ACCEL and certainly this topic, atrial fibrillation, is increasing at near epidemic proportions. I suppose your final message would be for us to stay abreast of new developments, and particularly to take a look at the new guidelines that have just been released.

Dr. Wellens: I completely agree, Sid.

Dr. Smith: Thank you very much, Hein.

Guidelines: Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246.

Slides

Slide 1 - Risk Factors for Ischemic Stroke and Systemic Embolism in Patients with Nonvalvular Atrial Fibrillation

Description: Data derived from collaborative analysis of five untreated control groups in primary prevention trials. As a group, patients with nonvalvular atrial fibrillation (AF) carry about a six-fold increased risk of thromboembolism compared with patients in sinus rhythm. Relative risk refers to comparison of patients with AF to patients without these risk factors. TIA = transient ischemic attack.

Slide 1: Risk Factors for Ischemic Stroke and Systemic Embolism in Patients with Nonvalvular Atrial Fibrillation

Citation: Reproduced with permission from Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246. Copyright of the American College of Cardiology.

Slide 2 - Recommended Doses of Drugs Proven Effective for Pharmacological Cardioversion of Atrial Fibrillation

Description: * Dosages given in the table may differ from those recommended by the manufacturers. †Insufficient data are available on which to base specific recommendations for the use of one loading regimen over another for patients with ischemic heart disease or impaired left ventricular function, and these drugs should be used cautiously or not at all in such patients. ‡The use of quinidine loading to achieve pharmacological conversion of atrial fibrillation is controversial, and safer methods are available with the alternative agents listed in the slide. Quinidine should be used with caution. AF = atrial fibrillation; BID = twice a day; GI = gastrointestinal; IV = intravenous. For the full list of references from which these recommendations are derived, please see the full text guidelines.

Slide 2: Recommended Doses of Drugs Proven Effective for Pharmacological Cardioversion of Atrial Fibrillation

Citation: Reproduced with permission from Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246. Copyright of the American College of Cardiology.

Slide 3 - Typical Doses of Drugs Used to Maintain Sinus Rhythm in Patients With Atrial Fibrillation*

Slide 3: Typical Doses of Drugs Used to Maintain Sinus Rhythm in Patients With Atrial Fibrillation*

Citation: Reproduced with permission from Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246. Copyright of the American College of Cardiology.

Slide 4 - Antithrombotic Therapy for Patients with Atrial Fibrillation

Slide 4: Antithrombotic Therapy for Patients with Atrial Fibrillation

Citation: Reproduced with permission from Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246. Copyright of the American College of Cardiology.

Slide 5 - Recommendations for Pharmacological Cardioversion of Atrial Fibrillation of Up to 7-Day Duration

Description: For the full list of references from which these recommendations are derived, please see the full text guidelines.

Slide 5: Recommendations for Pharmacological Cardioversion of Atrial Fibrillation of Up to 7-Day Duration

Citation: Reproduced with permission from Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246. Copyright of the American College of Cardiology.

Slide 6 - Recommendations for Pharmacological Cardioversion of Atrial Fibrillation Present for More Than 7 Days

Slide 6: Recommendations for Pharmacological Cardioversion of Atrial Fibrillation Present for More Than 7 Days

Citation: Reproduced with permission from Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246. Copyright of the American College of Cardiology.

Slide 7 - Aspirin and Warfarin in AF: Results of Major Trials

Description: The image to the right shows the results of trials comparing aspirin versus placebo as antithrombotic therapy to reduce stroke in patients with atrial fibrillation. Although all six trials showed trends toward reduced stroke using aspirin, this result was statistically significant only in the SPAF Study, which was stopped at an interim analysis due to aspirin's efficacy. The graphic on the left compares adjusted-dose warfarin versus aspirin. The effect of warfarin on stroke versus aspirin varied widely among these five trials. No statistically significant heterogeneity was seen (p = 0.09), and meta-analysis showed that adjusted-dose warfarin reduced overall relative risk for all stroke by 36% (95% CI, 14% to 52%) compared with aspirin. Horizontal lines are 95% CIs around the point estimates. AFASAK = Copenhagen Atrial Fibrillation, Aspirin, and Anticoagulation Study (I and II); EAFT = European Atrial Fibrillation Trial; ESPS II = European Stroke Prevention Study II; LASAF = Low-Dose Aspirin, Stroke, and Atrial Fibrillation Pilot Study; PATAF = Prevention of Arterial Thromboembolism in Atrial Fibrillation; SPAF = Stroke Prevention in Atrial Fibrillation Study; UK-TIA = United Kingdom TIA Study.

Slide 7: Aspirin and Warfarin in AF: Results of Major Trials

Citation: Reproduced with permission from ACP-ASIM. Hart RG, Benavente O, McBride R, Pearce LA. Antithrombotic therapy to prevent stroke in patients with atrial fibrillation: a meta-analysis. Ann Intern Med 1999;131:492-501.

References

  1. Go AS, Hylek EM, Phillips KA, et al. Prevalence of diagnosed atrial fibrillation in adults: national implications for rhythm management and stroke prevention: the AnTicoagulation and Risk Factors in Atrial Fibrillation (ATRIA) Study. JAMA 2001;285:2370-5.
  2. Friberg J, Buch P, Scharling H, et al. Rising rates of hospital admissions for atrial fibrillation. Epidemiology 2003;14:666-72.
  3. Le Heuzey JY, Paziaud O, Piot O, et al. Cost of care distribution in atrial fibrillation patients: the COCAF study. Am Heart J 2004;147:121-6.
  4. Fuster V, Ryden LE, Cannon DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. J Am Coll Cardiol 2006;48:e149-246.

Disclosure: The authors have nothing to disclose.

Cardiosource. 2006; ©2006 American College of Cardiology
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# posted by roodbont @ 6:12 AM 0 comments

Wednesday, December 27, 2006

 

anticoagulants

Terutroban and endothelial TP receptors in atherogenesis]
Tony J Verbeuren
Treatment of thrombotic diseases implicates the use of anti-platelet agents, anti-coagulants and pro-fibrinolytic substances. Amongst the anti-platelet drugs, aspirin occupies a unique position. As soon as it became evident that the major action of aspirin is indirect blockade, through inhibition of cyclooxygenase (COX), of the production of thromboxane A2 (TXA2), a powerful vasoconstrictor and platelet activator, research for new anti-thrombotics that interact more specifically with the production and/or the action of TXA2 was started. Terutroban (S 18886) is a selective antagonist of TP receptors, the receptors for TXA2, that are present on platelets and on vascular smooth muscle cells, but also on endothelial cells. The role played by the platelet and smooth muscle cell TP receptors in thrombotic disease is well known, and preclinical and clinical studies with terutroban have illustrated the powerful antithrombotic effects of this agent. The implication of endothelial TP receptors in the development of atherosclerotic disease has only been examined during the past five years and studies with terutroban have been crucial for understanding the role of these endothelial receptors in cardiovascular physiopathology. The goal of the present review is to discuss the arguments in favour of the hypothesis suggesting that activation of endothelial TP receptors, by causing expression of adhesion molecules, favours adhesion and infiltration of monocytes/macrophages in the arterial wall, thereby stimulating the development of atherosclerosis. The review will also highlight the important contribution of the studies performed with terutroban in this research area. The triple activity (anti-thrombotic, anti-vasoconstrictor, anti-atherosclerotic) observed with terutroban in preclinical studies, stressed by the first results in clinical development, places terutroban as an innovative drug with a unique potential for treatment of cardiovascular disorders.



Can J Cardiol. 2006 Feb ;22:149-51

# posted by roodbont @ 7:40 AM 0 comments
 

alendronate (bifosfanaat)

Stopping Alendronate After 5 Years Seems Safe for Most Women

Women who stopped taking alendronate appear after 5 years to maintain bone mineral density compared with those who continue taking the drug, researchers report in JAMA.

Some 1100 women who had been on the drug an average of 5 years were randomized to another 5 years' treatment with the drug or with placebo. Bone mineral density was measured at randomization and then annually thereafter. Total-hip BMD was the primary end point.

The women continuing alendronate maintained a higher BMD, relative to those switching to placebo, but the difference was only 2% to 3%. The risk for nonvertebral fractures did not differ significantly between the two groups, but the risk for vertebral fractures was higher in the women who discontinued alendronate.

Women at high risk for vertebral fractures ought to be considered for continued therapy, the authors suggest. An editorialist agrees that, otherwise, most women "can consider a 'holiday' period of up to 5 years without therapy."

JAMA article (Free abstract; full text requires subscription)

JAMA editorial (Subscription required)


# posted by roodbont @ 5:18 AM 0 comments

Saturday, December 23, 2006

 

melk en colonkanker

In the Cohort of Swedish Men, 45 306 men aged 45 to 79 years and without a history of cancer completed a food-frequency questionnaire in 1997 and were followed up through December 31, 2004.

During a mean follow-up of 6.7 years, 449 incident cases of colorectal cancer occurred. After adjustment for age and other risk factors, the multivariate rate ratio (RR) of colorectal cancer for men in the highest quartile of total calcium intake compared with those in the lowest quartile was 0.68 (95% confidence interval [CI], 0.51 - 0.91; P for trend = .01).

High dairy consumption was also associated with a lower risk for colorectal cancer. Colorectal cancer risk for 7 servings/day or more of total dairy foods was about half that for less than 2 servings/day (multivariate RR, 0.46; 85% CI, 0.30 - 0.71; P for trend = .01). Milk was the dairy food that was most strongly inversely associated with the risk for colorectal cancer.

For cancer subsites, RRs were 0.37 for proximal colon (95% CI, 0.16 - 0.88), 0.43 for distal colon (95% CI, 0.20 - 0.93), and 0.48 for rectum (95% CI, 0.23 - 0.99).

"Our findings provide support for inverse associations between intakes of calcium and dairy foods and the risk of colorectal cancer," the authors write. "The associations did not vary significantly by subsite in the colorectum."

Study limitations include possible misclassification of calcium intake, and the possibility of unmeasured confounders accounting for the observed associations.

"Future studies should examine the relation of other components of dairy foods, such as conjugated linoleic acid, sphingolipids, and milk proteins, with the risk of colorectal cancer," the authors conclude.

The Swedish Cancer Foundation, the Swedish Research Council-Longitudinal Studies, the Swedish Foundation for International Cooperation in Research and Higher Education (STINT), Västmanland County Research Fund against Cancer, Örebro County Council Research Committee, and Örebro Medical Center Research Foundation supported this study. The authors have disclosed no relevant financial relationships.

In an accompanying editorial, James C. Fleet, from Purdue University in West Lafayette, Indiana, calls this a powerful study with a large population linked to well-maintained, complete health records.

"Although this study offers some new insight into the dietary modulation of colon cancer, one is still likely to feel that this story has a lot more to reveal and that [this article] only begins to address these gaps," Dr Fleet writes. "Given that the interaction between vitamin D status and calcium metabolism is well established and that vitamin D status appears to modulate the effect of calcium on colon cancer risk, future studies on calcium or dairy intakes and cancer risk should not ignore it."

Dr Fleet has disclosed no relevant financial relationships.

Am J Clin Nutr. 2006;83:527-528, 667-673

Learning Objectives for This Educational Activity


# posted by roodbont @ 6:32 AM 0 comments

Thursday, December 21, 2006

 

atrial fibrillation apirin atenolol


Atrial Fibrillation

What is atrial fibrillation (AF)?

Atrial fibrillation is a disorder found in about 2.2 million Americans. During atrial fibrillation, the heart's two small upper chambers (the atria) quiver instead of beating effectively. Blood isn't pumped completely out of them, so it may pool and clot. If a piece of a blood clot in the atria leaves the heart and becomes lodged in an artery in the brain, a stroke results. About 15 percent of strokes occur in people with atrial fibrillation.

The likelihood of developing atrial fibrillation increases with age. Three to five percent of people over 65 have atrial fibrillation.

How is atrial fibrillation treated?

Several approaches are used to treat and prevent abnormal beating:

  • Medications are used to slow down rapid heart rate associated with AF. These treatments may include drugs such as digoxin, beta blockers (atenolol, metoprolol, propranolol), amiodarone, disopyramide, calcium antagonists (verapamil, diltiazam), sotalol, flecainide, procainamide, quinidine, propafenone, etc.
  • Electrical cardioversion may be used to restore normal heart rhythm with an electric shock, when medication doesn't improve symptoms.
  • Drugs (such as ibutilide) can sometimes restore the heart's normal rhythm. These drugs are given under medical supervision, and are delivered through an IV tube into a vein, usually in the patient's arm.
  • Radiofrequency ablation may be effective in some patients when medications don't work. In this procedure, thin and flexible tubes are introduced through a blood vessel and directed to the heart muscle. Then a burst of radiofrequency energy is delivered to destroy tissue that triggers abnormal electrical signals or to block abnormal electrical pathways.
  • Surgery can be used to disrupt electrical pathways that generate AF.
  • Atrial pacemakers can be implanted under the skin to regulate the heart rhythm.

AHA Recommendation for Stroke Prevention

Treating atrial fibrillation is an important way to help prevent stroke. That's why the American Heart Association recommends aggressive treatment of this heart arrhythmia.

Drugs are also used to help reduce stroke risk in people with AF. Anticoagulant and antiplatelet medications thin the blood and make it less prone to clotting. Warfarin is the anticoagulant now used for this purpose, and aspirin is the antiplatelet drug most often used. Long-term use of warfarin in patients with AF and other stroke risk factors can reduce stroke by 68 percent.

  • Physicians differ on the choice of drugs to prevent embolic stroke — stroke caused by a blood clot. It's clear that warfarin is more effective against this type of stroke than aspirin. However, warfarin has more side effects than aspirin. Examples include potential bleeding problems or ulcer.
  • Patients at high risk for stroke should probably be treated with warfarin rather than aspirin unless there are clear reasons not to do so.
  • Aspirin is the standard treatment for patients at low risk for stroke and under 75 years of age.

Arrhythmia News

For stroke information, visit StrokeAssociation.org or call the American Stroke Association at 1-888-4-STROKE. For information on life after stroke, ask for the Stroke Family Support Network.

See the Related Items


# posted by roodbont @ 2:51 PM 0 comments
 

arrhythmia

zie voor artikel op Google onder arrhythmia

# posted by roodbont @ 2:33 PM 0 comments
 

warfarin

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New Model Predicts Bleeding Risk in Elderly Warfarin Recipients


Information from Industry
Antibiotic Treatment for Many Outpatient and Inpatient Bacterial InfectionsLearn more about high-dose, short-course therapy, including PK/PD parameters, clinical benefits, and doctor and patient benefits.

By Will Boggs, MD

NEW YORK (Reuters Health) Dec 08 - A research group has developed and validated a contemporary model for bleeding risk in elderly patients with atrial fibrillation receiving warfarin, according to a report in the November issue of Chest.

"Consideration of the variables we have described can help clinicians identify older persons at low risk for bleeding events and improve the prescribing of warfarin in stroke prevention," Dr. Theresa I. Shireman from the University of Kansas Medical Center, Kansas City, told Reuters Health.

Dr. Shireman and colleagues collected data on 26,000 patients with AF from a registry of atrial fibrillation, and used Medicare claims to identify bleeding events requiring hospitalization. Candidate variables related to bleeding were selected for development of their model, incorporating three risk categories.

After a stepwise selection process, the 8 variables remaining in the model included age at least 70 years, female gender, remote bleeding event, recent bleeding event, alcohol or drug abuse, diabetes, anemia, and antiplatelet drug use.

"We were surprised that hepatic and renal failure were not significant and that other medications associated with bleeding risks were also not significant," Dr. Shireman said.

In the validation sample, the team reports, major bleeding events occurred in 0.9% of the low-risk individuals, 2.0% of the moderate-risk individuals, and 5.4% of the high-risk individuals.

Pair-wise comparisons showed all these rates to be significantly different from each other.

Based on Kaplan-Meier curves and c statistics, the new model provided better discrimination than two other currently used models among the bleeding risk groups.

This model also allows the separate quantification of the effects of each risk factor, the researchers note. "Validation of this model in other study populations is warranted," they suggest.

"Risk/benefit stratification schemas are designed to aid management decisions; and for bleeding risk, the new model by Shireman et al. looks very promising," Dr. Puneet Kakar and colleagues from University Department of Medicine, City Hospital, Birmingham, UK write in a related editorial.

"As is often the case, many patients who are at the highest risk of a bleed are also at the highest risk of having a stroke, and this clearly poses problems in management. Ultimately," the editorial concludes, "it may still be up to the patient and treating physician to decide each case on an individual basis."

Chest 2006;130:1390-1396,1296-1299.




# posted by roodbont @ 6:15 AM 0 comments

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