Patients With Paroxysmal Atrial Fibrillation Less Likely To Receive Anticoagulants

MedicalResearch.com Interview with:

Dr Nicola Adderley BA, MSci (Cantab), MA, MPhil, PhD Institute of Applied Health Research Research Fellow University of Birmingham

Dr. Adderley

Dr Nicola Adderley BA, MSci (Cantab), MA, MPhil, PhD
Institute of Applied Health Research
Research Fellow
University of Birmingham

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a major global public health problem. It is associated with a five-fold increase in risk of stroke.

There are three types of AF – paroxysmal, persistent or permanent. In paroxysmal AF, episodes come and go, and usually stop without any treatment. With persistent AF episodes can last for periods of more than seven days and are treated with medication or a medical procedure called cardioversion. In permanent AF, the irregular heartbeat is present all the time and cardioversion has failed to restore a normal heart rhythm.

All patients with AF, including paroxysmal AF, are at an increased risk of stroke. UK guidelines recommend anticoagulant treatment, such as the blood-thinning drug warfarin, for patients with all types of AF in order to reduce the risk of stroke.

Our study aimed to determine whether patients with paroxysmal AF are less likely to be treated with anticoagulants than patients with persistent or permanent AF and to investigate trends in treatment between 2000 and 2015.

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Normalizing Testosterone With Replacement Therapy Reduced Atrial Fibrillation Risk

MedicalResearch.com Interview with:

Rajat S. Barua, MD; PhD; FACC; FSCAI Associate Professor of Medicine (Cardiology), University of Kansas School of Medicine Director, Cardiovascular Research, Dept. of Cardiology, Kansas City VA Medical Center Director, Interventional Cardiology & Cardiac Catheterization Laboratory Kansas City VA Medical Center

Dr. Barua

Rajat S. Barua, MD; PhD; FACC; FSCAI
Associate Professor of Medicine (Cardiology), University of Kansas School of Medicine
Director, Cardiovascular Research, Dept. of Cardiology, Kansas City VA Medical Center
Director, Interventional Cardiology & Cardiac Catheterization Laboratory
Kansas City VA Medical Center

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation is the most common cardiac arrhythmia worldwide, with significant morbidity, mortality and financial burden. Atrial fibrillation is known to increase with age and is higher in men than in women. Although the underlying mechanisms of this sex difference are still unclear, one preclinical and several small clinical studies have suggested that testosterone deficiency may play a role in the development of atrial fibrillation. To date, no studies have investigated the effect of testosterone-level normalization on incidence of new atrial fibrillation in men after testosterone replacement therapy.

In this study, we investigated the incidence of atrial fibrillation in hypogonadal men with documented low testosterone levels. We compared the incidence of atrial fibrillation among patients who did not receive any testosterone replacement therapy, those who received testosterone replacement therapy that resulted in normalization of total testosterone, and those who received testosterone replacement therapy but that did not result in normal total testosterone levels.

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Biomarker VCAM-1 Associated With New Onset Atrial Fibrillation

MedicalResearch.com Interview with:
Stefan Kiechl, MD and
Karin Willeit, MD
Department of Neurology
Medical University Innsbruck
Innsbruck, Austria 

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common cardiac arrhythmia and a major contributor to thromboembolic stroke and population morbidity and mortality. Aside from well-established risk factors such as age, heart failure, and hypertension, inflammation has been suggested to play a significant role in the pathogenesis of AF. This is evidenced by histologic studies that found marked inflammatory infiltrates in atrial biopsies of AF patients and by epidemiological studies demonstrating an association of circulatory inflammation markers with incident AF. Of note, an increased endocardial expression of vascular intercellular adhesion molecule 1 (VCAM-1), a mediator of leukocyte trafficking, during rapid atrial pacing was demonstrated which was shown to contribute to an inflammatory and prothrombotic environment within atrial tissue.

Because it is still unclear whether inflammation related to AF is primarily a systemic or localized phenomenon, we sought to examine the association of 13 baseline inflammation markers with incident atrial fibrillation in the prospective population-based Bruneck Study and to replicate key findings in a second cohort, the SAPHIR Study.

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Valvular Heart Disease: Edoxaban vs Warfarin in the ENGAGE AF-TIMI 48 Trial

MedicalResearch.com Interview with:
Raffaele De Caterina MD, PhD

Professor of Cardiology and Director of the University Cardiology Division
‘G d’Annunzio’ University in Chieti

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The widely used term “valvular atrial fibrillation” encompasses a variety of conditions in which atrial fibrillation and valvular heart disease coexist. Since most trials of the non-vitamin K antagonist oral anticoagulants (NOACs) have variably excluded “valvular atrial fibrillation”, in more or less restrictive terms, there has been uncertainty whether NOACs can be used in such varied conditions. While atrial fibrillation in the presence of a mechanical valve or rheumatic mitral stenosis has to be a true contraindication (unfavorable data with one NOAC in the former setting; no data in the latter setting), patients with valvular diseases such as mitral insufficiency, aortic stenosis, aortic insufficiency, or with the presence of a bioprosthesis, have been variably included in the phase III trials of NOACs, but had not been extensively and conclusively studied before.

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Does Stress Raise Risk of Atrial Fibrillation?

MedicalResearch.com Interview with:

Simon Graff MD Department of Public Health Research Unit for General Practice Aarhus University Aarhus C, Denmark

Dr. Simon Graff

Simon Graff MD
Department of Public Health
Research Unit for General Practice
Aarhus University
Aarhus C, Denmark 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The presented study is a continuation of our interest in the role of stress and the possible causes of atrial fibrillation.  We published a study that showed that spousal bereavement were followed by a transiently increased risk of new onset of atrial fibrillation. With spousal bereavement being one of the most stressful life-event, we wanted to know whether minor and differentiated stress exposures had an effect as well. Therefore we used register based data on perceived stress as a new measure of exposure.

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Appropriate Anticoagulation Underutilized in Atrial fibrillation

MedicalResearch.com Interview with:
Dr. Ying Xian
 MD PhD
Department of Neurology,
Duke Clinical Research Institute
Duke University Medical Center
Durham, North Carolina

MedicalResearch.com: What is the background for this study?

Response: Atrial fibrillation (AF) is the most common arrhythmia. AF increases the risk for stroke and accounts for 10% to 15% of all ischemic strokes. While the burden of AF-related stroke is high, AF is a potentially treatable risk factor. Numerous studies have demonstrated that vitamin K antagonists, such as warfarin, or non-vitamin K antagonist oral anticoagulants (NOACs), reduce the risk of ischemic stroke. Based on these data, current guidelines recommend adjusted-dose warfarin or NOACs over aspirin for stroke prevention in high-risk patients with Atrial fibrillation.

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Stopping Warfarin in Dementia Patients with Atrial Fib Associated With Increased Risk of Stroke and Death

MedicalResearch.com Interview with:

Ariela Orkaby, MD, MPH Geriatrics & Preventive Cardiology Associate Epidemiologist Division of Aging, Brigham and Women's Hospital Instructor in Medicine, Harvard Medical School

Dr. Ariela Orkaby

Ariela Orkaby, MD, MPH
Geriatrics & Preventive Cardiology
Associate Epidemiologist
Division of Aging, Brigham and Women’s Hospital
Instructor in Medicine, Harvard Medical School

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Atrial Fibrillation is a common heart rhythm that affects 1 in 25 adults over age 60 and 1 in 10 adults over age 80. The feared consequence of atrial fibrillation is stroke, leading to the prescription of blood thinning medications (anticoagulants such as warfarin) to prevent strokes. However, there is an underutilization of these life-saving medications in older adults, and particularly in those who have dementia. In part, this is due to a lack of research and inclusion of older adults with dementia in prior studies.

In this study, we used clinical Veterans Administration data, linked to Medicare, to follow 2,572 individuals over age 65 who had atrial fibrillation and until a diagnosis of dementia. The average age was 80 years, and 99% were male. We found that only 16% remained on warfarin. We used statistical methods to account for reasons why a patient would or would not be treated with warfarin and found that those who continued to take warfarin had a significantly lower risk of stroke (HR 0.74, 95% Confidence interval 0.54- 0.99, p=0.47) and death (HR 0.72, 95% CI 0.60-0.87, p<0.01) compared to those who did not continue to take warfarin, without an increased risk of bleeding.

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Increase In Subdural Hematomas Associated With Increase Use of Antithrombotic Drugs


MedicalResearch.com Interview with:

David Gaist, MD, PhD</strong> Department of Neurology Odense University Hospital University of Southern Denmark Odense, Denmark

Dr. David Gaist

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The incidence of subdural hematoma (SDH; a bleed located within the skull, but outside the brain) has been reported to be on the increase. Previous studies have shown an association between use of antithrombotic drugs and SDH. However, studies with updated estimates of this risk and with focus on current more complex and aggressive regimens of antithrombotic treatment are scarce.

We therefore performed this study, where we identified 10,010 patients aged 20-89 years that were admitted with SDH in Denmark in 2000 through 2015. Preadmission use of antithrombotic drugs (low-dose aspirin, clopidogrel, vitamin K antagonist, e.g. warfarin, and direct oral anticoagulants) of these cases was compared to that of 400,380 individuals from the general population with no history of SDH (controls).

We found that use of antithrombotic drugs was associated with an increased risk of subdural hematoma . The magnitude of this risk varied by type of antithrombotic, and was, e.g., low for use of low-dose aspirin, and highest for warfarin. Further, with a single exception (low-dose aspirin and dipyridamole), concurrent use of more than one antithrombotic drug was associated with higher risk of SDH, particularly if warfarin was taken along with an antiplatelet drug, e.g., low-dose aspirin or clopidogrel. Increasing use of antithrombotic drugs was observed in the study period. The incidence of subdural hematomas in the Danish population also increased markedly in the years 2000-2015, particularly among those aged 75+ years. Our study indicates that this increased incidence, can, at least partly, be explained by increased use of antithrombotic drugs.

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Which AFib Patients Should Resume Warfarin After Intracranial Hemorrhage?

MedicalResearch.com Interview with:
Peter Brønnum Nielsen MD PhD
Aalborg Thrombosis Research Unit
Department of Clinical Medicine
Faculty of Health
Department of Cardiology, Atrial Fibrillation Study Group
Aalborg University Hospital
Aalborg, Denmark
 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response:   Patients who sustain an intracranial hemorrhage (ICH) event are often excluded from randomized trials investigating stroke prevention in atrial fibrillation (AF) by use of oral anticoagulant treatment.

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Variable Effects of Vitamin C on Post-Operative Atrial Fibrillation

MedicalResearch.com Interview with:

Dr-Harri-Hemilae.jpg

Dr. Harri Hemilae

Harri Hemilä, MD, PhD
Department of Public Health
University of Helsinki

MedicalResearch.com: What is the background for this study?

Response: I have a long term interest in vitamin C. Previously I have shown that it alleviates exercise-induced bronchoconstriction (EIB) (http://dx.doi.org/10.1186/1710-1492-10-58 ) and shortens the duration of colds ( http://dx.doi.org/10.1371/journal.pmed.0020168 ). Now I had been following the literature and I noted that a number of randomized trials were being published about vitamin C for preventing post-operative atrial fibrillation (POAF). Therefore I reasoned that it is worthwhile to analyze that set of trials

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