Author Interviews, Heart Disease / 28.07.2017

MedicalResearch.com Interview with: Tom Marshall, MSc, PhD, MRGP, FFPH Professor of public health and primary care Institute of Applied Health Research University of Birmingham Birmingham UK MedicalResearch.com: What is the background for this study? What are the main findings? Response: It is widely recognised that anticoagulants are underused in patients with atrial fibrillation (AF) although they are effective in reducing risk of stroke. We investigated whether this could be explained by the fact that many AF patients have conditions which are considered relative contraindications to their use. We analysed electronic medical records from 645 general practices from 2004 to 2015 and included over 1 million patients with AF. We found that about 6% of AF patients had are relative contraindications such as recent history of major bleeding. In each of the 12 years, similar numbers of patients with and without contraindications were prescribed anticoagulants. (more…)
Author Interviews, BMJ, Heart Disease / 14.06.2017

MedicalResearch.com Interview with: 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. (more…)
AHA Journals, Author Interviews, Heart Disease, Testosterone / 24.05.2017

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 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. (more…)
Author Interviews, Biomarkers, Heart Disease, JAMA / 30.03.2017

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. (more…)
Author Interviews, Heart Disease, JACC / 19.03.2017

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. (more…)
Author Interviews, Heart Disease / 15.03.2017

MedicalResearch.com Interview with: 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. (more…)
Author Interviews, Heart Disease, JAMA, Stroke / 14.03.2017

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. (more…)
Alzheimer's - Dementia, Author Interviews, Brigham & Women's - Harvard, Geriatrics, Heart Disease, Stroke / 26.02.2017

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 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. (more…)
Author Interviews, Heart Disease, JAMA / 25.02.2017

MedicalResearch.com Interview with: 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. (more…)
Author Interviews, Heart Disease, JAMA, Stroke / 25.02.2017

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. (more…)
Author Interviews, Heart Disease, Surgical Research, Vitamin C / 06.02.2017

MedicalResearch.com Interview with: 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 (more…)
Author Interviews, Heart Disease / 21.01.2017

MedicalResearch.com Interview with: Dr. Elena Arbelo MD PhD Department of Cardiology, Cardiovascular Institute Hospital Clínic de Barcelona University of Barcelona Barcelona, Spain MedicalResearch.com: What is the background for this study? What are the main findings? Response: Almost 20 years after its first description, catheter ablation is a widely-used treatment strategy for patients with symptomatic atrial fibrillation (AF) (AFib) resistant to antiarrhythmic drugs (AAD). If we look at the results of the ESC Pilot Atrial Fibrillation General Registry1, which included about 3000 consecutive in- and outpatients with AF presenting to cardiologists in nine participating countries in Europe, catheter ablation had previously attempted 7.6% overall, most often in those with paroxysmal AF (15.6%). A further 7.8% were prescribed an ablation as part of their management, which went up to a 19.3% in the case of paroxysmal AFib. On the other hand, several randomised clinical trials (RCTs) have shown better results of AFib ablation compared to antiarrhythmic drugs (AADs)2-6. However, these studies had a rather small sample size of selected patients, and interventions were undertaken by experienced operators with clearly pre-specified protocols. With rising prevalence of AFib and increasingly available treatment options, it was of utmost importance to have an accurate picture of contemporary AFib ablation and its outcomes which will allow the identification of practice gaps and assist evidence-based guidelines for the management of these patients. (more…)
Alcohol, Author Interviews, Heart Disease, JACC, UCLA / 02.01.2017

MedicalResearch.com Interview with: Gregory M Marcus, MD, MAS, FACC, FAHA, FHRS Director of Clinical Research Division of Cardiology Endowed Professor of Atrial Fibrillation Research University of California, San Francisco MedicalResearch.com: What is the background for this study? What are the main findings? Response: Moderate alcohol consumption has previously been associated with a decreased risk of heart attack. However, as we have previously shown that individuals who believe alcohol to be good for the heart tend to drink more, there is a concern that these previous data might appear to justify excessive alcohol consumption. In addition, previous research on the topic of alcohol consumption and heart disease has relied almost entirely on participant self-report, which is known to be particularly unreliable among heavy drinkers. Finally, previous research has sought to study relationships between alcohol and various types of heart disease, but there has not been an emphasis on individual-level characteristics that might influence these relationships. (more…)
Author Interviews, Heart Disease / 09.12.2016

MedicalResearch.com Interview with: Juhani Airaksinen, MD, PhD Professor, Chief of Cardiology Directork Heart Center Turku University Hospital MedicalResearch.com: What is the background for this study? What are the main findings? Response: Electrical cardioversion (ECV) is an essential part of rhythm control strategy in patients with paroxysmal atrial fibrillation (AF). There is limited information on unsuccessful outcome of ECV (i.e. failure of cardioversion or early recurrence of AF) for acute AF. Our study shows that the risk of unsuccessful outcome of ECV can be predicted using five simple clinical variables. These variables were used to derivate and validate a novel risk stratification tool (the AF-CVS Score) for predicting unsuccessful ECV outcome. Study patients with high AF-CVS Score points (>5) had a high incidence of ECV failure or early AF recurrence. (more…)
Author Interviews, CMAJ, Heart Disease, Stroke / 27.11.2016

MedicalResearch.com Interview with: Dr. Tony Antoniou, PhD Research Scholar Department of Family and Community Medicine and a Scientist Keenan Research Centre of the Li Ka Shing Knowledge Institute St. Michael's Hospital Assistant Professor in the Department of Family and Community Medicine and Leslie Dan Faculty of Pharmacy University of Toronto, Toronto, Ontario MedicalResearch.com: What is the background for this study? What are the main findings? Response: Dabigatran etexilate is an anticoagulant that is commonly used for stroke prevention in patients with atrial fibrillation. Absorption of dabigatran etexilate is opposed by intestinal P-glycoprotein, an efflux transporter. Once absorbed, dabigatran etexilate is converted to its active form by carboxylesterase enzymes. Unlike other statins, simvastatin and lovastatin can inhibit P-glycoprotein and carboxylesterase. This may result in increased absorption of dabigatran etexilate, thereby increasing the risk of bleeding. Conversely, inhibition of carboxylesterase may decrease the effectiveness of dabigatran etexilate. (more…)
Author Interviews, BMJ, Heart Disease, Technology / 15.10.2016

MedicalResearch.com Interview with: Dr. Ngai-yin Chan Princess Margaret Hospital Lai Chi Kok, Hong Kong MedicalResearch.com: What is the background for this study? Response: Atrial fibrillation (AF) is the most common sustained heart rhythm disorder which can cause stroke, heart failure and an increased risk of death. The risk of stroke can be reduced substantially with drug treatment. However, a quarter of patients with AF causing stroke have silent and asymptomatic AF before stroke. The current guidelines recommend opportunistic screening for AF. Whether systematic community screening for AF with a convenient smartphone ECG can reduce the burden of AF remains unknown. (more…)
AHA Journals, Author Interviews, Heart Disease, Pharmacology / 06.10.2016

MedicalResearch.com Interview with: Xiaoxi Yao, PhD, MPH, MS Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery Mayo Clinic Rochester, MN MedicalResearch.com: What is the background for this study? What are the main findings? Response: Atrial fibrillation (AF) is the most common arrhythmia requiring treatment, affecting 3-6 million Americans. AF is associated with a 5 fold risk of stroke, which can be substantially reduced by oral anticoagulants. For over a half century, warfarin was the only option for long-term oral anticoagulation in the U.S., but the use of warfarin can be cumbersome. Warfarin has numerous interactions with food and other drugs, and requires regular lab testing and dose adjustment. Since 2010, four non–vitamin K antagonist oral anticoagulants (NOACs) have been approved by the FDA. In comparison to warfarin, the fixed-dosage NOACs provide more convenient therapeutic options and demonstrated at least equivalent efficacy and safety in large phase III clinical trials. However, the outcomes achieved in idealized clinical trial settings may not necessarily translate to routine clinical practice. In this large cohort of patients with nonvalvular AF, we assessed the real-world effectiveness and safety of three NOACs (dabigatran, rivaroxaban, and apixaban), comparing each agent with warfarin. We found apixaban was associated with lower risks of both stroke and major bleeding, dabigatran was associated with similar risk of stroke but lower risk of major bleeding, and rivaroxaban was associated with similar risks of both stroke and major bleeding in comparison to warfarin. (more…)
Author Interviews, Clots - Coagulation, Heart Disease, Stroke / 13.09.2016

MedicalResearch.com Interview with: Menno Huisman, MD, PhD Associate professor Department of Medicine Leiden University Medical Center The Netherlands MedicalResearch.com: What is the background for this study? What are the main findings? Response: GLORIA™-AF is one of the largest ongoing global registry programs examining the use of oral antithrombotic agents in real-world clinical practice. The program is designed to characterize the population of newly diagnosed patients with non-valvular atrial fibrillation (NVAF) at risk for stroke, and to study patterns, predictors and outcomes of different regimens for stroke prevention. At the ESC Congress 2016, we presented the first Phase II results of GLORIA-AF from approximately 3,000 NVAF patients, which showed that treatment with PRADAXA was associated with low incidences of stroke, major bleeding and life threatening bleeding. Less than 1% of PRADAXA-treated patients experienced a stroke over two years (0.63%). Major bleeding occurred in 1.12% of PRADAXA-treated patients and 0.54% experienced a life-threatening bleed. (more…)
Author Interviews, BMJ, Heart Disease, Stroke / 12.09.2016

MedicalResearch.com Interview with: Ayodele Odutayo, DPhil student Centre for Statistics in Medicine Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences University of Oxford, Oxford, UK MedicalResearch.com: What is the background for this study? What are the main findings? Response: Atrial fibrillation is associated with an increased risk of all cause mortality and stroke, as well as higher medical costs and a reduced quality of life. The association between atrial fibrillation and cardiovascular outcomes other than stroke is less clear. We found that atrial fibrillation is associated with a wide range of cardiovascular events, including cardiovascular mortality, major cardiovascular events, heart failure, ischaemic heart disease, chronic kidney disease, and sudden cardiac death, as well as stroke and all cause mortality. The relative and absolute risk increase associated with many of these events is greater than that of stroke. Interventions are needed to reduce the risk of non-stroke cardiovascular outcomes in adults with atrial fibrillation. (more…)
Author Interviews, Heart Disease, Race/Ethnic Diversity, Stroke / 27.07.2016

MedicalResearch.com Interview with: Dr. Mary Vaughan Sarrazin PhD Associate Professor Department of Internal Medicine University of Iowa Roy and Lucille Carver College of Medicine, and Iowa City VA Medical Center, Center for Comprehensive Access & Delivery Research and Evaluation (CADRE) Iowa City MedicalResearch.com: What is the background for this study? Response: Atrial fibrillation is associated with a higher risk of stroke. The CHA2DS2VASc score (congestive heart failure, hypertension, age 75 or older, diabetes, previous stroke, vascular disease, age 65-74, female sex) reflects stroke risk and is used to guide decisions regarding anticoagulation. Our prior work suggests that African Americans have a higher risk of stroke compared to other patients with atrial fibrillation, even after risk factor adjustments. In the current study, we used Medicare data to test whether addition of black race to CHA2DS2VASc score improves stroke prediction in patients with atrial fibrillation. (more…)
Author Interviews, Heart Disease, Race/Ethnic Diversity / 18.07.2016

MedicalResearch.com Interview with: Evan L. Thacker, PhD. Assistant Professor College of Life Sciences Brigham Young University Provo, UT MedicalResearch.com: What is the background for this study? Response: Atrial fibrillation (AF) is diagnosed more commonly in whites than blacks in the United States. This seems paradoxical because blacks have higher prevalence of many risk factors for AF. Various explanations for this paradox have been proposed, including biological explanations as well as potential biases in research studies. We investigated one such bias – selection bias – as a potential explanation for the paradox. We did this by comparing the racial difference in atrial fibrillation prevalence among people who enrolled in an epidemiologic study versus people who were eligible to enroll in the study but did not enroll. (more…)
Author Interviews, Cancer Research, Heart Disease, JAMA / 26.05.2016

MedicalResearch.com Interview with: David Conen MD MPH Department of Medicine University Hospital Basel Basel Switzerland MedicalResearch.com: What is the background for this study? What are the main findings? Dr. Conen: A previous study of a contemporary population with atrial fibrillation (AF) treated with oral anticoagulation showed that over a third of all deaths were due to non-cardiovascular causes, and malignancies accounted for the largest proportion of these deaths. These data suggested that AF patients may have an increased risk of malignancies, but little data existed to support this hypothesis. During more than 19 years of follow-up, our study showed that atrial fibrillation was a significant risk factor for the occurrence of malignant cancer. After taking into account a large number of other risk factors and co-morbidities, the risk of cancer was approximately 50% higher among women with new-onset AF compared to women without AF. The risk of cancer was highest in the first 3 months after new-onset AF but remained significant beyond 1 year after new-onset AF (adjusted HR 1.42, p<0.001). We also observed a trend towards an increased risk of cancer mortality among women with new-onset AF. (more…)
Alzheimer's - Dementia, Author Interviews, Heart Disease / 06.05.2016

MedicalResearch.com Interview with: T. Jared Bunch, MD Director of Heart Rhythm Research Medical Director for Heart Rhythm Services Intermountain Healthcare System MedicalResearch.com: What is the background for this study? What are the main findings? Dr. Bunch: Approximately 6 years ago we found that patients with atrial fibrillation experienced higher rates of all forms of dementia, including Alzheimers disease. At the time we started to ask the questions of why this association existed. We know that atrial fibrillation patients experience higher rates of stroke. These patients are placed on blood thinners, most commonly warfarin, to lower risk of stroke which at the same time expose that patient to a higher risk of intracranial bleeding. One possibility to explain the association was that perhaps dementia in the manifestation of many small clots or bleeds in the brain that in total lead to cognitive decline. If this is the case, then the efficacy and use of anticoagulation is very important in atrial fibrillation patients. We conducted additional studies that showed this to be the case. In patients with no history of dementia, managed long-term with warfarin anticoagulation, those that had levels that were frequently too higher or too low that resulted in poor times in therapeutic range, experienced significantly higher rates of dementia. The risk was highest in younger atrial fibrillation patients that were less than 80 years of age. We then found that in atrial fibrillation patients that were frequently over anticoagulated and also use an antiplatelet agent, aspirin or plavix, the dementia rates nearly doubled. At this point we raised the question if atrial fibrillation increased the risk beyond anticoagulation, or does anticoagulation efficacy drive most of the risk. This question formed the background of the current study. (more…)
Author Interviews, Heart Disease, JAMA, Stroke / 04.05.2016

MedicalResearch.com Interview with: Dr. Ben Freedman OAM Deputy Director Research Strategy, Heart Research Institute/Charles Perkins Centre Professor of Cardiology, Sydney Medical School Head Vascular Biology Anzac Research Institute Honorary VMO, Concord Repatriation General Hospital University of Sydney MedicalResearch.com: What is the background for this study? Dr. Freedman: Guidelines recommend that patients with atrial fibrillation (AF) at high enough risk for stroke should be treated with anticoagulant. Anticoagulant drugs are remarkably effective in reducing stroke risk by about two thirds, and death by between a quarter and a third. Unfortunately, strokes can still occur when patients are prescribed anticoagulant for Atrial Fibrillation, and it is often presumed this residual risk of stroke represents treatment failure, though there are few data about this important issue. MedicalResearch.com: What are the main findings? Dr. Freedman: We were able to compare the risk of stroke in a cohort of patients with AF commenced on anticoagulant, with a very large closely-matched cohort seen in general practice at the same time but without AF. This is a unique comparison. We found that the residual risk of stroke in such anticoagulant-treated patients was virtually identical to that in the matched control cohort. The implication is that the residual risk of stroke may not be treatment failure, but the risk of non-cardioembolic stroke in people of a similar age and stroke risk profile but without Atrial Fibrillation. The residual risk of death in those on anticoagulant was higher than the matched controls, and intermediate between the control rate and the mortality rate for untreated AF. (more…)
Author Interviews, Heart Disease, Stroke / 22.02.2016

MedicalResearch.com Interview with: Dr. Rolf Wachter Head Senior physician University of Goettingen Göttingen, Germany Medical Research: What is the background for this study? What are the main findings? Dr. Wachter: Atrial Fibrillation is a known risk factor for stroke, and in stroke patients, it is a strong predictor of adverse outcome, if it is not adequately treated (e.g. by anticoagulation). However, in its paroxysmal form, Atrial Fibrillation (AF) may escape routine diagnostics. We aimed to show that we can increase the number of patients with detected AF if we do more monitoring for atrial fibrillation. As a unique feature of our study, we did not focus on a certain stroke subtype (i.e. cryptogenic stroke), but we aimed to consider all patients >= 60 years in whom the detection of Atrial Fibrillation has a clinical relevance. The main finding of our study was that enhanced and prolonged Holter ECG monitoring (3x10 days of monitoring, analysed in a dedicated core lab) tripled the number of detected AF cases (from 4.5 to 13.5 %). 11 patients had to undergo enhanced and prolonged monitoring to find one additional case of Atrial Fibrillation. (more…)
Author Interviews, Flu - Influenza, Heart Disease / 10.02.2016

MedicalResearch.com Interview with: Tze-Fan Chao MD PhD Division of Cardiology, Department of Medicine Taipei Veterans General Hospital Institute of Clinical Medicine, and Cardiovascular Research Center National Yang-Ming University, Taipei, Taiwan Su-Jung Chen MD Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Institute of Public Health and School of Medicine, National Yang-Ming University Taipei, Taiwan MedicalResearch: What is the background for this study? What are the main findings? Response: Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice, accounting for frequent hospitalizations, hemodynamic abnormalities, and thromboembolic events. Although the detailed mechanism of the occurrence of Atrial fibrillation remains unclear, systemic inflammation and sympathetic nervous system have been demonstrated to play an important role in the pathogenesis of AF. Flu (influenza infection) is a common disease which could happen to everyone in the daily life. It could cause significant morbidity and mortality, and is a serious human health concern worldwide. Previous studies have shown that influenza infection not only results in the productions of pro-inflammatory cytokines, but also activates the sympathetic nervous system, which are all related to the occurrence of Atrial fibrillation. Therefore, we hypothesized that influenza infection could be a risk factor of new-onset AF. We also tested the hypothesis that influenza vaccination, a useful way to reduce the risk of influenza infection, could decrease the risk of AF. In this large scale nationwide case-control study, a total of 11,374 patients with newly diagnosed Atrial fibrillation were identified from the Taiwan National Health Insurance Research Database. On the same date of enrollment, 4 control patients (without AF) with matched age and sex were selected to be the control group for each study patient. The relationship between AF and influenza infection/vaccination 1 year before the enrollment was analyzed. The results showed that influenza infection was associated with an 18% increased risk of AF, and the risk could be easily reduced through influenza vaccination. (more…)
Author Interviews, Clots - Coagulation, Heart Disease, Stroke, University of Michigan / 10.11.2015

MedicalResearch.com Interview with: Geoffrey Barnes, MD, MSc Clinical Lecturer Cardiovascular Medicine and Vascular Medicine University of Michigan Health System Medical Research: What is the background for this study? Dr. Barnes: Although warfarin has been the primary anticoagulant used for stroke prevention in atrial fibrillation for over 60 years, four new direct oral anticoagulants (DOACs) have been introduced into the market since 2010. Dabigatran, which directly inhibits thrombin, was found to have better prevention of ischemic stroke and a significant reduction in hemorrhagic stroke (bleeding strokes) for patients with atrial fibrillation at intermediate and high risk of stroke. Prior cost-effectiveness studies have shown that dabigatran is cost-effective from both the societal and payer (usually Medicare) perspectives. However, none of those studies looked at the patient’s out-of-pocket costs and the impact of prescription drug coverage Medical Research: What are the main findings? Dr. Barnes: We found that patients with prescription drug coverage (Medicare Part D) had significant cost savings when choosing dabigatran over warfarin. This is primarily because of the reduction in both types of stroke as well not needing to have frequent blood draws, as are required by warfarin. However, when patients do not have prescription drug coverage, the costs for dabigatran are quite high. (more…)
Author Interviews, Clots - Coagulation, Heart Disease, JACC / 24.10.2015

H.A. (Hendrika) van den Ham PharmD Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences Utrecht University The Netherlands. MedicalResearch.com Interview with: H.A. (Hendrika) van den Ham PharmD Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences Utrecht University The Netherlands. Medical Research: What is the background for this study? What are the main findings? Dr. van den Ham: Atrial fibrillation (AF) is associated with a substantial risk of ischemic stroke and thromboembolism. The CHADS2 and the CHA2DS2-VASc risk scores are developed to guide the decision to prescribe anticoagulants. Recently a new clinically-based risk score, the ATRIA study risk score, was developed. We compared the predictive ability of the ATRIA risk score with the CHADS2 and CHA2DS2-VASc risk scores in a large, independent, community-based cohort of Atrial fibrillation patients in the United Kingdom. We found that the ATRIA score more accurately identified low risk patients that the CHA2DS2-VASc score assigned to higher risk categories. Such reclassification of stroke risk could prevent overuse of anticoagulants in very low stroke risk patients with Atrial fibrillation. (more…)
Author Interviews, Cleveland Clinic, Cost of Health Care, Heart Disease, JAMA, Radiology / 16.09.2015

Wael A. Jaber, MD FACC, FAHA Professor of Medicine Cleveland Clinic Lerner College of Medicine Fuad Jubran Endowed Chair in Cardiovascular Medicine Heart and Vascular Institute Cleveland Clinic Cleveland, OH MedicalResearch.com Interview with: Wael A. Jaber, MD FACC, FAHA Professor of Medicine Cleveland Clinic Lerner College of Medicine Fuad Jubran Endowed Chair in Cardiovascular Medicine Heart and Vascular Institute Cleveland Clinic Cleveland, OH Medical Research: What is the background for this study? What are the main findings? Prof. Jaber: Risk stratification of patients presenting with atrial fibrillation often includes a non-invasive evaluation for coronary artery disease. However, the yield of such testing in patients without angina or anginal-equivalent symptoms is uncertain. That is, how often do we find silent myocardial ischemia? In our cohort of 1700 consecutive patients with atrial fibrillation, less than 5% had ischemia on nuclear stress testing, even though comorbidities were prevalent. Moreover, in patients with ischemia that had invasive coronary angiography, less than half had obstructive coronary artery disease. (more…)
Author Interviews, Clots - Coagulation, Heart Disease, JACC / 17.07.2015

Prof. Johan Bosmans Interventional cardiologist University Hospital Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium Medical Research Interview with: Prof. Johan Bosmans Interventional cardiologist University Hospital Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium MedicalResearch: What is the background for this study? What are the main findings? Prof. Bosmans : Transcatheter aortic valve replacement (TAVR) has become standard of care for patients who cannot undergo surgery. With this, it is important to ensure that the risks associated with TAVR be fully understood, and if possible prevented. Even at this stage of the adoption of TAVR, large trials continue to provide information to the clinician about how to select the right patients to ensure the best possible outcomes. The ADVANCE Study is a prospective, multicenter study that evaluated the use of TAVR in 1015 patients at 44 experienced TAVR centers, which was designed to reflect routine clinical practice. We know that the risk of serious adverse events, such as stroke or transient ischemic attack (TIA), in post-TAVR patients can vary based on the timing before and after the procedure. A patient’s baseline demographics and medical history can affect their risk of procedure-related events as well as long-term outcomes. The manipulations required crossing the aortic valve and appropriately positioning any type of TAV has been thought to be related to procedural stroke events. Therefore, we performed a multivariable analysis looking for predictors of stroke – or stroke and TIA at 3 unique time periods (periprocedural, early and late) following TAVR. The most striking result from our analyses was that we were not able to identify any predictors of periprocedural (either during the procedure or on the day after) stroke, illustrating this very multifactorial etiology. We were able to show that being female, experiencing acute kidney injury or a major vascular complication positively predicted stroke during the early (2-30 days post procedure) time period. When we combined the outcome of stroke or TIA, we found that a history of prior atrial fibrillation (AF) was also a predictor. The only late predictor (day 31-730 post-procedure) of stroke was a history of coronary artery bypass grafting, which could reflect the patients’ risk of vascular disease. (more…)