Heart Rhythm 2010: Meeting Highlights

The Heart Rhythm Society's 31st Annual Scientific Sessions took place May 12-15, 2010 in Denver, Colorado. Enclosed below is a compilation of clinical news highlights from the meeting.    

Heart Rhythm Society Releases Expert Consensus Statement on Management of Cardiovascular Implantable Electronic Devices

   The Heart Rhythm Society (HRS) has released the first consensus statement for the management of cardiovascular implantable electronic devices in patients nearing end of life or requesting device deactivation. The HRS Expert Consensus Statement on the Management of Cardiovascular Implantable Electronic Devices (CIEDs) in patients nearing end of life or requesting withdrawal of therapy was written in collaboration with representatives from the American College of Cardiology (ACC), the American Geriatrics Society (AGS), the American Academy of Hospice and Palliative Medicine (AAHPM), the American Heart Association (AHA) and the European Heart Rhythm Association (EHRA). The CEIDS Management Consensus Statement was presented at Heart Rhythm 2010.    For decades, CIEDs — pacemakers, implantable cardioverter-defibrillators (ICDs), and more recently cardiac resynchronization therapy (CRT) devices — have proven to save lives in various populations at risk of serious heart rhythm disorders. As indications for device therapy continues to expand, the population of patients with these devices continues to grow. The new consensus statement is the first to offer clinicians and industry guidance on the management of CIEDs in those patients at the end of their lives or requesting with- drawal of device therapy.     “The overall understanding of device deactivation varies, and addressing device management with patients nearing the end of their lives can be very uncomfortable for many clinicians,” stated lead author of the statement, Rachel Lampert, MD, FHRS, Yale University School of Medicine in New Haven, CT. “The goal of this document is to provide clinicians with an understanding of the ethical and legal principles underlying device deactivation as well as guidance on communication about device deactivation with patients.”    The Heart Rhythm Society brought together a diverse panel of experts to comprehensively address the legal, ethical and religious principles supporting device deactivation in patients who have made this decision. To address the topic, a multidisciplinary group was convened and consisted of electrophysiologists, patients and representatives from the fields of geriatrics, palliative care, psychiatry, nursing, law, ethics and divinity.    The consensus statement outlines common ethical and legal concerns related to withdrawing CIED therapies (device deactivation), a decision-making algorithm for withdrawing CIED therapies, how CIED-related ethical conflicts can be prevented, and the rights and responsibilities of the clinician whose personal beliefs preclude his/her participation in device deactivation.    The new consensus statement presents several key points:    • A patient with decision-making capacity has the legal right to refuse or request the withdrawal of any medical treatment or intervention, regardless of whether he or she is terminally ill, and regardless of whether the treatment prolongs life and its withdrawal results in death.    • Legally and ethically, carrying out a request to withdraw life-sustaining treatment is neither physician-assisted suicide nor euthanasia.    •The right to refuse or request the withdrawal of a treatment is a personal right of the patient and does not depend on the characteristics of the particular treatment involved (i.e., CIEDs).    • A clinician cannot be compelled to carry out an ethically- and legally-permissible procedure (i.e., CIED deactivation) that he or she personally views as in conflict with his/her personal values. In these circumstances, the clinician cannot abandon the patient but should involve a colleague who is willing to carry out the procedure.    • Communication about CIEDs should be a part of a larger conversation about patients’ goals of care. The role of the clinician is to help patients determine how the benefits and burdens of device therapy align with their desired outcomes for their health care.    • Communication about CIED deactivation is an ongoing process that starts prior to implant and continues over time as a patient's health status changes.    • Any physician or center that implants CIEDs should have a clearly defined process to withdraw therapies at such a time that becomes appropriate.    •The deactivation process should include anticipation of symptoms and appropriate palliative care planning tailored to individual patients’ needs, as well as the needs of family members when appropriate.     “Most clinicians who care for patients with cardiac devices regard the therapies delivered by those devices to be life-sustaining, and for that reason, device deactivation is a challenging practice for many clinicians to execute,” stated co-lead author of the statement, David Hayes, MD, FHRS, Mayo Clinic in Rochester, MN. “It is extremely important for clinicians to have a point of reference, and this document provides guidance for device deactivation in patients with CIEDs.”    The complete guidance will be published in the July edition of HeartRhythm, the official journal of the Heart Rhythm Society.

Cardiac Resynchronization Therapy Reduces All-cause Mortality in Women

   According to a sub-study of the Multicenter Automatic Defibrillator Implantation Trial-CRT (MADIT-CRT), females receive a clinically significant benefit from cardiac resynchronization therapy devices (CRT-D) compared to men. New research presented at Heart Rhythm 2010 indicates that CRT-D therapy reduces all-cause mortality and heart failure (HF) and death endpoint in females, but not in males.    In MADIT-CRT, patients were randomly assigned to receive CRT-D or ICD therapy. A total of 1,820 patients were enrolled in 110 hospitals, and a significant portion of the patient population was women (25 percent). In the results of MADIT-CRT, CRT-D was associated with a 34 percent overall reduction of death and HF in minimally symptomatic patients, yet CRT-D was more effective in women than men.    The sub-study of the MADIT-CRT study, led by Aysha Arshad, MBBS, and Arthur J. Moss, MD, sought to compare outcomes in men and women who participated in MADIT-CRT and identify the factors associated with gender differences in HF or death and all-cause mortality.     “Historically, women are significantly underrepresented in large device trials, and MADIT-CRT provides a unique study population with more than 25 percent of the patients being women,” stated Aysha Arshad, MBBS, St. Luke's and Roosevelt Hospital Center and Columbia University College of Physicians and Surgeons in New York, NY. “The results of our research from the MADIT-CRT population show women benefit significantly more than men when it comes to CRT-D therapy.”    Results of the sub-study on MADIT-CRT found females receive a significant benefit from CRT-D therapy by reducing all-cause mortality by 72 percent. Specifically, mortality reduction was especially prominent in women with QRS duration greater than 150ms and in women with left bundle branch block. In addition, heart failure and death endpoints in the female population were reduced by 69 percent, compared to only 28 percent in the male population.    According to the MADIT-CRT sub-study, CRT-D therapy proves significantly beneficial to women, and the favorable results were associated with consistently greater echocardiographic evidence of reverse cardiac remodeling in female patients. Reverse cardiac remodeling can further benefit patients’ overall health and ultimately improve survival in patients with advanced heart failure.

African Americans Experience Radically Lower Incidence of Postoperative Atrial Fibrillation Despite Having High Risk Factors

   African Americans have a significantly lower incidence of postoperative atrial fibrillation (AF) compared to Caucasians despite a higher prevalence of risk factors for this specific type of arrhythmia. According to a new study presented at Heart Rhythm 2010, Caucasians are 60 percent more likely than African Americans to develop AF following heart surgery.    In the United States, more than 2 million people are living with AF, making it one of the most common heart rhythm disorders. Risk factors currently known to be associated with AF include gender, age, hypertension, diabetes and cardiovascular disease; however, race has not been considered a risk factor, but recent studies have shown a correlation.    The study examined adult patients, without prior AF, who underwent coronary artery bypass graft (CABG) surgery at Henry Ford Health System between 2004 and 2008. A total of 1,001 patients were identified for the study – 731 Caucasians and 270 African Americans. Prior to surgery, patients were measured for high risk factors including age, congestive heart failure, hypertension and diabetes.    Study results show African American patients have a higher prevalence of risk factors associated with AF compared to Caucasian patients, including congestive heart failure, hypertension and diabetes. However, despite the significantly higher presence of risk factors in African Americans, only 18 percent of the African American patients developed postoperative CABG AF compared to 29 percent of Caucasian patients. Further studies are needed to determine the underlying factors that protect African Americans from developing postoperative AF.     “Based on our study results, it seems viable for clinicians to consider race as an important factor in the likelihood of patients developing postoperative AF,” stated Marc K. Lahiri, MD, Henry Ford Health System in Detroit, MI. “Since it appears that Caucasians are at an increased risk of developing postoperative AF, clinicians may want to use this information in deciding when to take measures to prevent its occurrence, such as using antiarrhythmic medications at the time of surgery.”

Herbal and Nonherbal Supplements Compromise Safety and Effectiveness of Warfarin

   Common herbal and nonherbal supplements, such as garlic, ginkgo and essential fatty acids, contribute to an increased risk of health complications in patients treated with warfarin. According to a new study released at Heart Rhythm 2010, eight out of the top ten supplements commonly taken by American consumers have been reported to impact the effectiveness of warfarin and overall safety of the individual.    Nearly 20 percent of Americans use herbal and nonherbal supplements, yet many patients do not disclose supplement intake with physicians. A new study conducted by a team of researchers from Intermountain Health Center analyzed the top 20 herbal and 20 nonherbal supplements taken by Americans based on 2008 sales data. Researchers examined supplement and drug interactions with reported changes in International Normalized Ratio (INR), bleeding and thromboembolic events.    Findings reveal that of the top ten most commonly used herbal and nonherbal supplements – glucosamine, chondroitin, co- enzyme Q10, multi-herbs, probiotic, antioxidants, melatonin, cranberry and soy – more than 90 percent have been reported to interact negatively with warfarin. Of the 40 most commonly taken supplements, 35 percent were associated with a significant change in INR, 64 percent increased the risk of bleeding and 36 percent decreased the effectiveness of warfarin.     “Most people don’t perceive herbal and nonherbal supplements as medication, so they don’t share information with their doctors about the supplements they are taking,” stated Jennifer Strohecker, PharmD, at Intermountain Medical Center in Salt Lake City,UT. “Typically, people take supplements with the intention of improving their health; however, many supplements can have an undesirable interaction with other medications. It’s important for patients to disclose as much information as possible about how they are treating themselves to ensure they receive the highest quality of care possible.”

Remote Monitoring Dramatically Improves Time to Treatment and Detection of AF in Elderly Patients

   According to a new study released at Heart Rhythm 2010, remote monitoring proves effective for earlier detection of arrhythmic events and pacemaker dysfunction in elderly patients with atrial fibrillation (AF). The study is the first to consider using remote monitoring on elderly patients to detect and treat AF compared to standard follow-up procedures.    The randomized, prospective study conducted at the Heart Institute (InCor), University of Sao Paulo Medical School in Sao Paulo, Brazil, evaluated 267 patients age 60 years and older with atrioventricular pacemaker implantation. Between March 2007 and September 2009, all patients were randomly assigned to a remote group (RG = 135) and a control group (CG = 132). Follow-up with patients was conducted in months 1, 3, 6, 12, 18 and 24, during which variables such as age, gender, follow-up time, time to AF diagnostic,AF burden and health complications (i.e., AF incidence, stroke) were analyzed.    Time to first AF detection was nearly twice as fast in patients in the RG (48 days in RG vs. 85 days in CG, P=0.047). The majority of AF episodes detected by remote monitoring (96 percent) were asymptomatic or silent AF; however, in 86.5 percent of the patient population, remote monitoring indicated the need for therapy change. As a result, nearly nine out of ten elderly patients diagnosed with AF required alternate treatment or pacemaker reprogramming: antithrombotic therapy in 52 percent, antiarrhythmic therapy in 22 percent, pacemaker reprogramming in 4 percent and cardioversion in 4 percent.”    We believe that utilizing remote monitoring for managing AF is not only safe, but more effective in comparison with standard follow-up treatments,” stated lead author Carlos E. Lima, MD, Heart Institute (InCor), University of Sao Paulo Medical School. “By reducing the recurrence of AF, thromboembolic events and symptoms related to AF, remote monitoring can improve the patient’s overall quality of life and help determine the best possible treatment.”    Results of the study showed a high incidence of AF among the patient population, 18.7 percent with an average follow-up of 252 days. The population was composed of elderly pacemaker patients with structurally normal hearts and isolated degenerative disease of the conduction system.

Catheter Ablation of AF Significantly Reduces Risk of Alzheimer's Disease and Stroke

   New findings reveal catheter ablation treatment of atrial fibrillation (AF) reduces the risk of stroke, mortality, Alzheimer’s disease (AD) and other forms of dementia. According to two new studies presented at Heart Rhythm 2010, patients with AF treated with catheter ablation are less likely to develop AD or other forms of dementia and have a significantly reduced risk of stroke and death compared to patients with AF who are not treated with ablation.    Over a three-year period, 37,908 patients were enrolled in a large, ongoing prospective AF study at Intermountain Medical Center. Patients were split into three groups all matched in gender and age: AF ablation patients, AF patients treated with medications and patients without AF. Two studies led by John D. Day, MD, and T. Jared Bunch, MD, from the Heart Institute at Intermountain Medical Center in Salt Lake City, evaluated the long-term effects of ablation treatment on patients with AF and the likelihood of developing dementia, Alzheimer’s Disease, stroke, and death. Both studies showed that 64 percent of AF patients treated with catheter ablation were cured of AF and off antiarrhythmic medications at the end of the three-year period.    Findings showed that AF ablation patients have a significantly lower risk of developing AD or other forms of dementia in a large cohort of patients. Specific study findings include:    •AF ablationpatients: 0.2 percent developed AD and 0.4 percent developed other forms of dementia    • AF patients with no ablation (treated with medications): 0.9 percent developed AD and 1.9 percent developed other forms of dementia    Results also revealed that AF patients who underwent catheter ablation had a lower risk of stroke and death when compared with AF patients who did not receive ablation treatment. Specific study findings include:    • AF ablation patients: 2.2 percent suffered a stroke and the mortality rate was 6%     • AF patients with no ablation (treated with medications): 4.7 percent suffered a stroke and the mortality rate was 23.5 percent     “With millions of people affected by atrial fibrillation, it is our hope that findings from studies like ours will help clinicians determine the best possible care and treatment options for patients,” stated Dr. Day. “Our studies shed light on the positive outcomes of catheter ablation treatment not only to reduce AF, but also to help AF patients lower their risk of developing Alzheimer’s disease, suffering from a stroke or worse, loss of life.”