Oral anticoagulation in nonvalvular atrial fibrillation

Detection of paroxysmal atrial fibrillation in 994 patients with a cerebrovascular event by intermittent 21-day ECG-monitoring and 7-day continuous Holter-recording

BACKGROUND

The detection of paroxysmal atrial fibrillation (AF) is of importance in stroke care. The method used is continuous electrocardiogram (ECG)-monitoring or multiple short ECG-recordings during an extended period. Their relative efficiency is a matter of discussion. In a retrospective cohort study on 994 patients with an ischemic stroke or transient ischemic attack (TIA), we have compared continuous 7-day monitoring to intermittent recording 60 sec three times daily with a handheld device during 3 weeks. We related the result to subsequent occurrence of AF as detected in 12-lead ECG recordings.

METHODS

The patients were identified in the local database of cardiovascular investigations. Their clinical profile and vital status during the follow-up were obtained from the Swedish Stroke Register and the Swedish general population registry. For comparison, we used an age- and sex-matched population with no known cerebrovascular event and a population with a cerebrovascular event that was not screened.

RESULTS

AF was detected in 7.1% by continuous screening and in 5.1% by intermittent screening (P = 0.3). During follow-up of 32 months, AF in 12-lead ECG was found in 7.0%. In the subgroup with positive screening, 46.3% had AF compared with 6.7% in the subgroup with negative screening (P < 0.0001).

CONCLUSIONS

The two screening approaches had a similar yield of arrhythmia, in spite of the group with intermittent monitoring having a more favorable clinical profile. A positive screening was highly predictive of AF in ECG during the follow-up.

Prevention of Venous Thromboembolism After Stroke

Venous thromboembolism (VTE) is a common complication following acute ischemic and hemorrhagic stroke. Pulmonary embolism (PE), the most serious consequence of deep vein thrombosis (DVT), can result in significant morbidity and death. Patients with stroke are at particular risk because of limb paralysis, prolonged bed rest, and increased prothrombotic activity. Preventive measures should be taken at all levels of care and can include mechanical calf compression, antiplatelet agents, and the use of anticoagulants such as heparin and low molecular weight heparin. Prevention of VTE should be incorporated into all stroke care pathways.

Atrial fibrillation after isolated coronary surgery affects late survival

BACKGROUND

Atrial fibrillation (AF) after coronary artery bypass graft surgery is a difficult problem and a continuing source of morbidity and mortality. However, the prognostic implications of postoperative AF are still in dispute. Our aim was to ascertain the impact of AF after coronary artery bypass graft on postoperative survival and to assess its prognostic role in cause-specific mortality.

METHODS AND RESULTS

We conducted a prospective observational study of 1832 patients undergoing isolated coronary artery bypass graft between January 2000 and December 2005 at 2 cardiac surgery centers in northern Italy. Patients affected by postoperative AF were identified and followed up until death or study end (April 30, 2007). A total of 570 patients (31%) developed AF after coronary surgery. Patients affected by postoperative AF experienced a longer hospital stay (7 days [25th to 75th percentile, 7 to 10 days] versus 7 days [25th to 75th percentile, 6 to 8 days]; P<0.001). Hospital mortality also was higher in AF patients (3.3% versus 0.5%; P<0.001). On discharge, 1806 patients were alive; 143 were lost to follow-up. The remaining 1663 were followed up for a median of 51 months (25th to 75th percentile, 41 to 63 months); 126 of them died after a median of 14 months (25th to 75th percentile, 5 to 32 months). Long-term mortality rates were significantly higher for patients with postoperative AF (2.99 per 100 person-years; 95% confidence interval, 2.33 to 3.84; 61 deaths) compared with those without the arrhythmia (1.34 per 100 person-years; 95% confidence interval, 1.05 to 1.71; 65 deaths), with an adjusted hazard ratio of 2.13 (P<0.001) and 2.56 (P=0.001) when also accounting for the prescription of warfarin at discharge. With Cox regression, patients with AF were shown to be at higher risk of dying from embolism (adjusted hazard ratio, 4.33; 95% confidence interval, 1.78 to 10.52) but not from other causes.

CONCLUSIONS

Postoperative AF affects early and late mortality after isolated coronary artery bypass graft surgery. Patients affected by AF are at higher risk of fatal embolic events. Careful postoperative surveillance with a specific antiarrhythmic and antithrombotic prophylaxis, aimed at reducing AF and its complications, is recommended.

[Portable coagulometers: a systematic review of the evidence on self-management of oral anticoagulant treatment]

BACKGROUND AND OBJECTIVE

We aimed to systematically review the scientific evidence about the use of portable coagulometers for patient's self-management of oral anticoagulant treatment.

MATERIAL AND METHOD

Systematic review of scientific evidence available from MEDLINE'S, DARE's, HTA-Database's, NHS-EED's and The Cochrane Library' s bibliographic databases, from their origin to March 2003. Randomized control trials (RCT) and Quasi-Experimental trials were selected provided that they compared patients in self-management with patients under usual care. The quality of scientific evidence was elicited using the Scottish Intercollegiate Guideline Network (SIGN) recommendations, whilst efficacy and security were descriptively summarized.

RESULTS

Twelve (7 RCT and 5 quasi-experimental trials) articles were found, and only two of them provided grade A recommendation. Patients under self-management remained the same or more time in the therapeutic range. The incidence of adverse effects in self-management patients was the same or less than that in patients under usual care.

CONCLUSIONS

The quality of the scientific evidence is heterogeneous. For selected patients, patient's self-management is at least as effective and safe as usual care. New oral anticaogulants, which have shown promising results, should be scrutinized for future changes in service provision.

Thromboembolic prophylaxis in nonrheumatic atrial fibrillation: utilization patterns, efficacy, and complications in a long-term follow-up of community patients

OBJECTIVES

To define the incidence, contemporary utilization patterns, efficacy, and complications of thromboembolic prophylactic treatment in patients with chronic (CAF) and paroxysmal atrial fibrillation (PAF).

BACKGROUND

Although recent randomized trials with antithrombotic therapy in nonrheumatic atrial fibrillation (AF) patients emphasized the benefits of warfarin in preventing stroke, warfarin treatment is still far from optimal.

METHODS

A retrospective analysis of the medical records of 506 patients with nonrheumatic PAF or CAF from 23 clinics in the north of Israel, including an interview with the patients' family physician.

RESULTS

(1) The most effective treatment for preventing thromboembolic events (a reduction of 75.9%) was warfarin at an international normalized ratio (INR) intensity of 2-3. (2) After diagnosis, 26.9% of the patients were treated with warfarin. (3) During the follow-up period (not following a thromboembolic event), an additional 26.9% of the patients began treatment with warfarin. (4) Elderly patients (p<0.001), patients with limited activity of daily living (ADL) (p<0.012) or instrumental activity of daily living (IADL) (p<0.001), and patients with PAF (p<0.0001) were less likely to be treated with warfarin. (5) Three new risk factors found for thromboembolic event were limited ADL (p<0.001), limited IADL (p<0.002), and extended duration of AF (p<0.006).

CONCLUSIONS

Less than optimal utilization patterns of thromboembolic prophylactic treatment with anticoagulants were found, especially regarding elderly patients, patients with limited ADL and IADL, and patients with PAF, despite the fact that their thromboembolic risk is as high or higher than that of other patients with AF.

Physician compliance with outpatient oral anticoagulant guidelines in Auvergne, France

OBJECTIVE

Oral anticoagulants (OA) are commonly used, but they can lead to severe bleeding. We studied the indications and monitoring of OA in patients treated by general practitioners.

DESIGN

Retrospective cross-sectional study.

SETTING

Primary care.

PATIENTS

Four hundred thirty-eight randomly selected patients of a population of 2,452 patients treated with OA were studied.

INTERVENTIONS

We compared the indications for OA as reported by general practitioners with indications as defined according to recent guidelines.

MAIN RESULTS

Twenty-five percent of patients should not have been treated with OA. Inappropriate indications (13% of patients) were atrial fibrillation without risk factor (3.9%), prior uncomplicated myocardial infarction (2.7%), peripheral arterial disease (2.7%), superficial thrombophlebitis (2.3%), and atherothrombotic ischemic stroke (1.6%). For 12% of patients, the duration of OA was too long (venous thromboembolism without permanent risk factor in 10%). Frequency of International Normalized Ratio (INR) measurement was insufficient for 14% of patients and target INR was not achieved in 31%.

CONCLUSIONS

Our study demonstrated that clinicians' adherence to recommendations regarding indications for OA and management of this treatment should be improved. Implementation of anticoagulation clinics is probably needed.

Ximelagatran compared with warfarin for prevention of thromboembolism in patients with nonvalvular atrial fibrillation: Rationale, objectives, and design of a pair of clinical studies and baseline patient characteristics (SPORTIF III and V)

BACKGROUND

Ximelagatran is a novel, oral direct thrombin inhibitor under investigation as an alternative to warfarin for prevention of thromboembolism in patients with nonvalvular atrial fibrillation (AF). Two long-term studies in patients with AF and at least one additional risk factor for stroke are underway to compare the safety and efficacy of fixed-dose ximelagatran (36 mg bid) without coagulation monitoring with dose-adjusted warfarin (international normalized ratio 2.0-3.0).

METHODS

SPORTIF III is a randomized, open-label, parallel-group study with blinded event assessment involving 3407 patients at 259 sites in 23 countries. SPORTIF V is similar, but with double-blind treatment allocation involving 3922 patients at 409 North American sites. The primary end point in each study is the incidence of all strokes and systemic embolic events, and the objective is to establish the noninferiority of ximelagatran relative to warfarin. Secondary end point constellations include (1) death, stroke, systemic embolism, and myocardial infarction; (2) ischemic stroke, transient ischemic attack, and systemic embolism; and (3) bleeding and treatment discontinuation. Blinded central committees adjudicate all end points and monitor patient safety. The studies commenced July 2000; enrollment ended in December 2001. Each study will accrue > or =4000 patient-years and > or =80 primary end points with a minimum per-patient exposure of 12 months. Combined analysis of both studies is also planned.

RESULTS

The demographics of the 2 patient populations are similar and should allow the studies to meet the objective.

CONCLUSIONS

The program, the largest conducted in this indication, will determine the safety and antithrombotic efficacy of ximelagatran as an alternative to warfarin for prevention of thromboembolism in patients with AF.

Managing anticoagulation in patients with atrial fibrillation

Patients with nonvalvular atrial fibrillation have an increased risk of cerebral thromboembolism. Oral anticoagulation therapy, however, provides primary and secondary stroke prevention in these patients. Here, update your knowledge of warfarin initiation, titration, monitoring, and adjustment.