[Atrial fibrillation in 2010: an increasing morbidity and mortality burden]

Use of Vitamins K antagonists in non-valvular atrial fibrillation thromboembolic risk prevention in Burkina Faso

Introduction

Atrial fibrillation is the commonest cardiac rythm disorder. Thromboembolic accidents are common complications that should be prevented by anticoagulant treatment. The aim of our study is to assess the use of vitamins K antagonists in the prevention of thromboembolic risk in atrial fibrillation.

Methods

It was a descriptive retrospective study of patients folders, performed in the cardiology department from January 1st 2010 to December 31st 2011. The study included all patients with non valvular atrial fibrillation. Thromboembolic risk was assessed through the CHA2DS2VASc score, and hemorrhagic risk through the HAS-BLED score.

Results

Atrial fibrillation accounted for 10.6% of all hospitalizations (103/970). Five patients had contra indication to anticoagulants. Non valvular AF was noticed in 68 cases (66%). The non valvular AF was chronic in 40 cases (59%) and paroxystic in eight cases (12%). The median age of the population was 64.5+13.8 years old. Median CHA2DS2VASc score was 3.9 + 1.6. Two patients had a score < 1. Sex, place of residence, age > 65, and cardiac failure did not interfere with prescription of vitamins K antagonists. Ischemic stroke and intra cavity thrombus were the indications for vitamins K antagonists’ prescriptions. The median HAS-BLED score was 3.5 + 1.5. The rate of vitamins K antagonists use was 35.3%. One case of death due to hemorrhagic stroke was noticed.

Conclusion

Guidelines on thromboembolic risk prevention are poorly used in the cardiology department. But the use of scoring systems allows the assessment of vitamins K antagonists treatment benefit/risk in atrial fibrillation, and minimizes the hemorrhagic risk.

Endoscopic mucosal resection of early oesophageal neoplasia in patients requiring anticoagulation: is it safe?

BACKGROUND AND AIM

Endoscopic mucosal resection (EMR) has become the standard treatment for early oesophageal neoplasia. The mucosal defect caused by EMR usually takes several weeks to heal. Despite guidelines on high-risk endoscopic procedures in patients on anticoagulation, evidence is lacking whether EMR is safe in such patients. We investigated the immediate and delayed bleeding risk in patients undergoing diagnostic or therapeutic oesophageal EMR comparing patients requiring warfarin anticoagulation with a control group.

METHODS

Warfarin was stopped 5 days before the planned EMR and restarted on the evening following the procedure. Patients with high-risk conditions, such as recent pulmonary thromboemboli, received bridging with low molecular weight heparin. All EMRs were performed when the INR was <1.5. Bleeding events on the day of the EMR and within 3 months post-procedure were documented.

RESULTS

One hundred and seventeen consecutive patients with early oesophageal neoplasia were included. Sixty-eight EMRs were performed in 15 patients requiring anticoagulation. One patient on warfarin was readmitted 10 days after EMR with haematemesis and melaena. Out of 400 EMRs in 102 controls, 26 immediate bleeding events occurred requiring endoscopic intervention. One delayed bleeding event (melaena) occurred in the control group. The number of bleeding events did not differ between groups [p = 0.99; odds ratio 1.01 (0.30-3.44)], neither for acute (p = 0.76) nor delayed bleeding (p = 0.24).

CONCLUSION

EMR of early oesophageal neoplasia can be safely performed in patients requiring anticoagulation when warfarin is discontinued 5 days before the endoscopic intervention and reinstituted on the evening of the procedure day.

Direct vitamin K antagonist anticoagulant treatment health care costs in patients with non-valvular atrial fibrillation

Background

There is evidence suggesting that most thromboembolic complications could be prevented with adequate pharmacological anticoagulation. We estimated the direct health care costs of anticoagulant treatment with oral vitamin K antagonists in patients diagnosed with non-valvular atrial fibrillation.

Methods

This observational study examined the clinical records of patients diagnosed with non-valvular atrial fibrillation who received anticoagulant treatment with oral vitamin K antagonists. Data from clinical records were used in the study: international normalized ratio, number of monitoring visits, type of anticoagulant, hospital admissions from complications, and concomitant medication. Drug cost was calculated based on the official Spanish Ministry of Health price list. Monitoring expenses were included the cost of the medical supplies used in the procedures. Hospitalization costs were calculated using the Diagnosis Related Group price for each case. Hospital visits costs were calculated by one of four different scenarios, using either the invoice rates for the regional health care authority or cost per visit as established by analytical accounting methods.

Results

We collected data from 1,257 patients diagnosed with non-valvular atrial fibrillation who were receiving oral anticoagulant therapy. Depending on the scheme used, the direct health care costs for these patients ranged from €423,695 - €1,436,038 per annum. The average cost per patient varied between €392 - €1,341, depending on the approach used. Patients with international normalized ratio values within the therapeutic range on 25% of their visits represented an average cost between €441.70 - €1,592. Those within the therapeutic range on 25%–50% of visits had associated costs of €512.37 - €1,703.91. When international normalized ratio values were within the therapeutic range on 50% - 75% of the visits, the costs ranged between €400.80- €1,375.74. The average cost was €305.23 - €1,049.84 when the values were within the therapeutic range for over 75% of visits.

Conclusions

Most direct health care costs associated with the sampled patients arise from the specialist-care monitoring required for the treatment. Good monitoring is inversely related to direct health care costs.

Protein analysis of atrial fibrosis via label-free proteomics in chronic atrial fibrillation patients with mitral valve disease

Background

Atrial fibrosis, as a hallmark of atrial structure remodeling, plays an important role in maintenance of chronic atrial fibrillation, but interrelationship of atrial fibrosis and atrial fibrillation is uncertain. Label-free proteomics can implement high throughput screening for finding and analyzing pivotal proteins related to the disease.. Therefore, we used label-free proteomics to explore and analyze differentially proteins in chronic atrial fibrillation patients with mitral valve disease.

Methods

Left and right atrial appendages obtained from patients with mitral valve disease were both in chronic atrial fibrillation (CAF, AF≥6 months, n = 6) and in sinus rhythm (SR, n = 6). One part of the sample was used for histological analysis and fibrosis quantification; other part were analyzed by label-free proteomic combining liquid chromatography with mass spectrometry (LC-MS), we utilized bioinformatics analysis to identify differential proteins.

Results

Degree of atrial fibrosis was higher in CAF patients than that of SR patients. 223 differential proteins were detected between two groups. These proteins mainly had vital functions such as cell proliferation, stress response, focal adhesion apoptosis. We evaluated that serine/threonine protein kinase N2 (PKN2), dermatopontin(DP), S100 calcium binding protein B(S100B), protein tyrosine kinase 2(PTK2) and discoidin domain receptor tyrosine kinase 2(DDR2) played important roles in fibrotic process related to atrial fibrillation.

Conclusion

The study presented differential proteins responsible for atrial fibrosis in chronic atrial fibrillation patients through label-free proteomic analysis. We assessed some vital proteins including their characters and roles. These findings may open up new realm for mechanism research of atrial fibrillation.

The predictive value of cardiac biomarkers in prognosis and risk stratification of patients with atrial fibrillation

PURPOSE OF REVIEW

Atrial fibrillation is a significant public health issue considering its high prevalence in the general population, and is associated with an increased risk of cardiovascular mortality and morbidity and thrombo-embolic complications.Asymptomatic paroxysms of atrial fibrillation occur frequently in the first stages of the disease but patients present to the doctor at a relatively late stage when the associated complications have already taken place. It is crucial to identify such patients as early as possible in order to start preventive therapy. Clinical diagnostic tests to identify patients prone to atrial fibrillation complications have not yet been developed as the exact mechanism and substrate of subclinical atrial fibrillation are not known. Further research is necessary to understand the pathophysiology of subclinical atrial fibrillation and to identify potential risk markers that determine the development and prognosis of the disease.

RECENT FINDINGS

Biomarkers have recently been identified which have been shown to be related to the incidence of atrial fibrillation and its prognosis. They reflect inflammation, neurohumoral activation and subclinical heart damage.

SUMMARY

New biomarkers may help to understand the mechanisms of subclinical atrial fibrillation and signal the likelihood of disease progression. Such biomarkers, though subject to further validation, may be of value in predicting the prognosis and guiding the treatment of patients with atrial fibrillation. They may enhance the ability of risk scores to guide anticoagulant treatment strategies.