Feb-04

Efficacy of Rhythm-Control Therapy to Prevent AF Recurrence Limited The results of a recent study have shown a trend toward a lower rate of early atrial fibrillation (AF) recurrence at 24 hours after direct-current (DC) cardioversion in patients receiving rhythm-control therapy. Still, the high incidence of treatment failure with antiarrhythmic medications at one month suggests that rate-control therapy with anticoagulation should be preferred in patients with new-onset AF, particularly if atrial fibrillation recurs after cardioversion, say investigators. The results of the study are published in the January 2004 issue of the American Journal of Cardiology. According to lead author Dr. Huagui Li from Creighton University in Omaha, Nebraska, and colleagues, while rate control is recommended as the preferred strategy for recurrent AF, the appropriate strategy for new-onset persistent AF is uncertain. It is thought that patients with new-onset paroxysmal AF may not need antiarrhythmic drug therapy because AF recurrence is unpredictable. For patients with new-onset AF requiring DC cardioversion, AF recurrence is also unknown, write the authors. To evaluate the AF recurrence rate and the impact of rhythm-control drugs class 1A, 1C, and 3 antiarrhythmic drugs in patients with new-onset persistent AF after successful DC cardioversion, the authors studied consecutive patients who underwent DC cardioversion of AF from January 1996 to December 1999. During this time, a total of 150 patients met the criteria for new-onset persistent AF. After the first DC cardioversion, fifty patients received rhythm-control therapy and 100 did not (rate-control group). At 24 hours after DC cardioversion, there was a trend toward a lower incidence of early AF recurrence in the rhythm-control group than in the rate-control group (6% vs. 16%; p = 0.11). At one month, the recurrence of AF in the rhythm-control group was 30% compared with 41% in the rate-control group (p = 0.25). The statistical difference in AF between the two groups became apparent at six months. Recurrence-free survival continued to decrease during the follow-up period in both groups, write Li et al. AF recurrence continued to increase in patients receiving rhythm-control drugs during the follow-up period, write the authors. By 24 months, the AF-recurrence-free survival rate was Successful Treatment of AF may be Overestimated The results of a recent study have shown a remarkably high incidence of recurrent atrial fibrillation (AF) both asymptomatic and symptomatic in patients with a history of AF despite optimized antiarrhythmic therapy. Of particular importance, the investigators note that many AF relapses lasted for relatively long periods of time and that freedom from AF for periods longer than three months did not preclude subsequent recurrences. The efficacy of pharmacologic and nonpharmacologic treatment modalities (i.e., catheter ablation of AF) may be significantly overestimated in clinical studies as well as in clinical practice, conclude lead author Dr. Carsten W. Israel from the J.W. Goethe University Hospital in Frankfurt, Germany, and colleagues. According to the investigators, the results support the continued use of anticoagulation therapy in patients with AF, adding that a significant proportion of patients with asymptomatic, undetected AF continue to be at increased risk for ischemic stroke after withdrawal of anticoagulation. The results of the study are published in the January issue of the Journal of the American College of Cardiology. In an editorial accompanying the study, Drs. Elizabeth S. Kaufman and Albert L. Waldo from Case Western Reserve University in Cleveland, Ohio write that the findings have important clinical implications, stressing that caution must be exercised when AF is believed suppressed. The implications for treatment are clear, namely that apparent freedom from AF does not, per se, obviate the need for oral anticoagulation, write Kaufman and Waldo. AF is associated with a substantial morbidity that is linked primarily to symptoms, heart failure, and thromboembolic events. Pharmacologic and nonpharmacologic therapies that control rhythm and rate often eliminate or reduce the symptoms of AF, and anticoagulation therapy has been shown to reduce the risk of thromboembolic events. In the editorial, Kaufman and Waldo note that when AF is thought to be suppressed usually equated with the absence of clinical symptoms and the presence of only sinus rhythm documented by ECG anticoagulation is often stopped, with physicians wishing to avoid the perceived risks, burdens, and inconveniences of warfarin therapy. This prospective study was designed to evaluate AF recurrences, particularly asymptomatic AF recurrence, over a long period of time in patients fitted with a new implantable pacemaker with sophisticated arrhythmia-documentation capabilities (AT500 pacemaker, Medtronic Inc., Minneapolis, Minnesota). Patients eligible for the study were those with a documented history of paroxysmal AF and who had a class I indication for physiologic pacing, such as sick sinus syndrome or atrioventricular block. A total of 110 patients were included in the study. The primary endpoint of the trial was defined as the incidence of AF lasting > 48 hours, as documented by the implanted device, in asymptomatic patients presenting in sinus rhythm during follow-up visits at one month, three months, and six months, and six-month intervals thereafter. Patients were followed for a mean of 19 ± 11 months. Antiarrhythmic drug therapy was optimized, if necessary, over the first month after device implantation and remained constant for the duration of the study period. All patients were receiving oral anticoagulation therapy (INR 2.0-3.0), except for those with contraindications. A total of 50 patients had AF episodes lasting > 48 hours as documented by the implanted device. Of these patients, nineteen (38%) were asymptomatic and presented in normal sinus rhythm during their respective follow-up visit. The prevalence of asymptomatic AF found incidentally on clinical examination was approximately 20%, note Israel et al. Of the 110 patients, 67 were free from AF for three months or longer, as documented by the device. In 11 of these patients (16%), symptomatic or asymptomatic AF recurrences lasting > 48 hours were documented in subsequent follow-up visits. These observations demonstrate that the success rates of maintaining continuous sinus rhythm in patients with a history of AF are often grossly overestimated, write Israel and colleagues. The authors note that all patients who received the implantable device with monitoring features for AF also had a class I indication for physiologic pacing, thus, the findings apply to patients with bradycardia requiring pacing. However, they conclude it is likely that the study s findings can also be applied to patients with AF and antiarrhythmic drug treatment in the absence of bradycardia. Although it is known that AF recurrence exists, Waldo and Kaufman write, the magnitude of the problem is only now being appreciated. They note the high incidence of asymptomatic AF largely explains the results of the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) trial, in that those patients with risk factors for stroke whose AF is thought suppressed remain at considerable risk if warfarin is stopped. In AFFIRM, 57% of the strokes in the rhythm-control arm occurred in those patients who stopped taking warfarin. Once there is an indication for warfarin in patients with a history of AF, should it ever be permanently stopped? The answer seems to be no, write Kaufman and Waldo. While there are numerous difficulties in administering warfarin, the newer oral direct thrombin-inhibiting anticoagulants may one day be a practical alternative to warfarin, they write. If the safety and efficacy of the oral direct thrombin inhibitors continue to be supported by subsequent studies, they should make it far easier for physicians to provide safe and effective oral anticoagulant therapy to patients with fibrillation who need it, they add. Philips and EP MedSystems Form Alliance to Offer Broad Electrophysiology Solutions Royal Philips Electronics and EP MedSystems, Inc. announced the formation of an alliance to address the increasing need for a comprehensive electrophysiology lab solution for the diagnosis and treatment of cardiac rhythm disorders, which affect 2.2 million people in the U.S. and more than five million worldwide. This agreement combines Philips best-in-class cardiovascular X-ray technology with EP MedSystems' technologically advanced EP recording and data management systems. By combining high-quality imaging on the Philips Allura X-ray imaging system with superior signal quality of the EP-WorkMate ® recording, stimulation, and mapping platform, EP MedSystems and Philips will offer electrophysiology solutions that will increase the overall effectiveness of patient procedures by enhancing present EP capabilities. Products from the collaboration will initially be available in the U.S with the global cardiovascular market to follow. Cardiac electrophysiology evaluates the electrical system of the heart, and is mainly concerned with studying the cause and treatment of abnormalities in the heart s rhythm, which are called arrhythmias. Cardiac arrhythmias are caused by disturbances in the electrical activation of the heart muscle that ultimately cause the heart to pump less efficiently. Cardiac rhythm disorders result in more than 1.2 million hospitalizations and 400,000 deaths each year in the United States, and account for about 20% of all chronic heart conditions. These conditions are diagnosed and treated by electrophysiologists and cardiologists who specialize in the diagnosis and treatment of these cardiac arrhythmias. We have had a long-standing commitment to cardiovascular care at Philips and will continue to look for and work with top-quality partners to advance cardiovascular technologies, said Willem Vuisting, Senior Vice President, Cardiovascular X-ray, Philips Medical Systems. This alliance with EP MedSystems, following our recent announcement to conduct research with Massachusetts General Hospital in this field, and our collaboration with Stereotaxis, will greatly expand Philips position in the electrophysiology market a key cardiovascular field that is growing worldwide. Reinhard Schmidt, President and CEO of EP MedSystems commented Philips Medical Systems is the premier provider of diagnostic radiographic and fluoroscopic equipment for cardiac catheterization suites, and we are pleased to partner with them to provide a complete EP lab solution for healthcare providers. Physicians and hospital administrators can look to this alliance for creative EP solutions, both now and in the future. We are looking forward to a long and productive relationship with Philips. EP MedSystems develops and markets cardiac electrophysiology products used to diagnose and treat certain cardiac rhythm disorders. The company's EP product line includes the EP-WorkMate ® Electrophysiology Workstation, the EP-3i Stimulator, diagnostic electrophysiology catheters and related disposable supplies, the ALERT ® System and ALERT family of internal cardioversion catheters and the ViewMate ® intracardiac ultrasound catheter imaging system. Medtronic Paceart Extends Patient and Device Data Accessibility to Healthcare Information Systems Medtronic, Inc. announced that it has begun the distribution of the Medtronic Paceart ® System, 2004 First Edition, to help clinics that specialize in heart rhythm disorders improve the electronic organization of cardiac device and patient heart rate data. The new release significantly expands the accessibility of data managed within Paceart by providing an electronic interface between the Paceart system and a broad array of healthcare information systems (HIS). The new export module uses XML and PDF standards for data transmission and formatting, which enables broad compatibility with and access from other systems. The 2004 First Edition reflects Paceart s continued commitment to be the leading universal clinic solution for collecting and managing patient and device data from remote and in-clinic data acquisition and device management systems. As more people receive implantable cardioverter-defibrillators, cardiac resynchronization therapy devices and pacemakers to treat heart disorders, it is increasingly necessary for clinics to efficiently manage information about their patients and the valuable data extracted from their devices, said Donald L. Deyo, General Manager of Medtronic Paceart. The new HIS export capability extends Paceart s data acquisition and management functionality by making the information broadly available to meet the demands of today s healthcare environment. In addition to the HIS export capability, the 2004 First Edition software incorporates several additional new features, including enhanced HIPAA tools for additional patient data security; data import support for more devices, including the Vitatron C-Series pacemaker and additional Biotronik pacemakers; a collection of data at the time of device implant to help provide continuity of care for patients with a new device; and automated event recorder transmission processing, which provides improved clinician productivity and efficiency. Medtronic plans to introduce updated editions of the Paceart system twice a year in an effort to continually help clinicians improve the management of patients with implantable cardiac devices. More than 900 cardiology and electrophysiology clinics use the Paceart system to provide ongoing management of patients with heart rhythm problems. Short-QT Syndrome and Sudden Death: Mutation Identified Researchers have found a genetic mutation that causes short-QT syndrome, a recently identified condition in which affected individuals have a high risk of sudden death. Reporting in Circulation online, Dr. Ramon Brugada from the Masonic Medical Research Laboratory in Utica, New York, and colleagues explain that short-QT syndrome was first identified in one family three years ago, and data from another two families have confirmed that this was an inherited condition. The syndrome confers a high degree of sudden death in infants, children, and young adults. In one family, a boy aged eight months suffered aborted sudden death and now has severe neurological damage; his brother died suddenly at age three months and was diagnosed as having sudden infant death syndrome (SIDS). People just accept SIDS as something natural, but in years to come I think you will find it disappears (as a diagnosis), because it s really a conglomerate of diseases that occur before the age of one, Brugada commented. Arrhythmias, such as those that occur with short-QT syndrome, account for a very small proportion of SIDS. Using genetic material from the families already identified as having short-QT syndrome, Brugada and colleagues have found that a mutation affecting the cardiac potassium HERG channel is the culprit. The mutation is autosomal dominant and is found on chromosome 7, Brugada says. The result is that the heart overworks electrically, he notes. Those affected develop atrial fibrillation, which can turn into ventricular fibrillation and sudden death. His team is testing different ways of prolonging the QT interval in affected patients. In older children and adults, defibrillators can be implanted, but these are not yet an option for babies and very young children, he says, because they are still of considerable size. They have also tested drugs that prolong the QT interval, such as sotalol, which they found had no effect, and quinidine, which works well, he says. The key to whether a certain drug works seems to be whether it affects the HERG channel or not. For it to be effective in this syndrome, it needs to stop the HERG channel from working. University Community Health and GE Medical Systems Unveil Plans for the Southeast s First Digital, Research-Focused Heart Hospital Pepin Heart Hospital & Research Institute to Provide Enhanced Care and Research for Patients with Cardiovascular Disease in the Southeast United States University Community Health (UCH) system and GE Medical Systems announced that they have entered into a Strategic Alliance Agreement to build one of the nation's most advanced heart hospitals. Under the agreement, GE Medical Systems will be the technology provider for UCH's new cardiovascular hospital, designed to deliver an unprecedented standard of cardiovascular care in the Southeast using advanced digital technology, when it opens in the spring of 2005. UCH will break ground on the $40 million, 120,000 square foot hospital in January 2004 on the campus of University Community Hospital in Tampa, Florida. The advanced specialty facility, to be named the Pepin Heart Hospital and Research Institute, will be designed as a virtually paperless, filmless and wireless environment, enabling clinicians to focus on providing the highest quality, most informed care to their patients. At the core of the digital workflow will be GE s Centricity Cardiology Information System and Centricity Clinical Information System, a complete, fully-electronic patient record system that enables doctors and nurses to view patient information anytime, from inside or outside the hospital and make care decisions right at the patients bedside. Computerized physician order entry will allow clinicians to electronically order medications, which will help reduce the opportunity for medical errors. The facility will feature the most advanced diagnostic and imaging technologies from GE, such as the Innova ® all-digital cardiovascular imaging system, the all-digital Vivid 7 Cardiovascular Ultrasound system, and Centricity Picture Archiving and Communications System (PACS), which allows clinicians to manage digital patient images. Other leading technology from GE to be featured at the Pepin Heart Hospital includes several Dash patient monitors, the MUSE ECG management system, and the Mac-Lab ® hemodynamic monitoring system. The commitment of GE Medical Systems to develop a showcase facility for their technology is a huge plus for our state and our community, said Florida Governor Jeb Bush. Not only will this enhance Florida s medical capabilities, but it will add to the expanding role that Florida is enjoying as a world-class destination for biotech and medical engineering, research and development. We welcome the opportunity to demonstrate to the nation and the world that Florida is leading the way with the newest technologies for cardiovascular research and care. We re proud to announce plans to join with UCH to create a truly leading edge, digital cardiovascular hospital, said Dow Wilson, President and CEO, GE Medical Systems Information Technologies. The Pepin Heart Hospital and Research Institute will become a model for a new generation of cardiovascular care in the Southeast and across the nation. UCH is a leading pioneer in the digital transformation of health care, and we re looking forward to embarking on this exciting joint initiative. Together, we will work to enhance the quality of patient care through research-based care, while further advancing GE s technologies, added Wilson. In addition to state-of-the art technology, the hospital will also feature an expanded research program that will build on the collaborative efforts already in place with the National Institutes of Health, Duke University s Clinical Research Facility, the Cleveland Clinic, Washington Hospital Center, Mayo Clinic and other world-renown research facilities. This research has enabled the Pepin Heart & Vascular Institute to introduce lifesaving procedural and technological breakthroughs long before they became available in most other hospitals. In addition, a large-scale auditorium will host clinical research and education seminars and symposiums for clinicians throughout the region. We are at a defining moment in health care. There is currently no resource of this scale in the Southeast and only a few in the world that can provide the patient care, service, innovation and capacity that we envision for the Pepin Heart Hospital and Research Institute, said Norm Stein, President of University Community Health. Pepin Heart Hospital and its team of physicians and staff are enthusiastic to partner with GE, the leader in medical technology. GE is known globally for its ability to provide a distinctive breadth of services from clinical information systems and CT scanners to lighting as well as strong implementation experience. We are contracting with a company that shares our vision to fundamentally change the way health care is delivered. Our objective is to create a facility that focuses on the patient and offers clinicians an environment where they can deliver the best patient care available today. With GE as our technology partner, we will be uniquely positioned to fulfill that vision, added Stein. The facility will be another example of UCH s commitment to provide high-quality health care services to this community, said Robert Anderson, Chairman of the Board for University Community Health. The new Pepin Heart Hospital will include a 52-bed pre/post cardiac unit, 16 cardiovascular critical care beds, a 20-bed cardiac surgery recovery unit, 48 progressive care beds, five surgical suites, ten cardiac catheterization/invasive procedure labs with additional diagnostic equipment, and a dedicated auditorium to be used for education and training presentations. AstraZeneca Submits New Drug Application (NDA) for Investigational EXANTA ® (ximelagatran) as First New Oral Anticoagulant in Over 50 Years AstraZeneca announced that it has submitted a New Drug Application (NDA) with the U.S. Food and Drug Administration (FDA) seeking marketing clearance for its investigational oral direct thrombin inhibitor EXANTA ® (ximelagatran) for the prevention of venous thromboembolism (VTE) in patients undergoing knee-replacement surgery; for the prevention of stroke and other thromboembolic complications associated with atrial fibrillation (AF); and for the long-term secondary prevention of VTE after standard treatment for an episode of acute VTE. AstraZeneca also announced that regulatory submissions for EXANTA have been made in Europe to the Reference Member State, France, as part of the Mutual Recognition Procedure for use of EXANTA in prevention of stroke and other thromboembolic complications associated with AF and the treatment of VTE. The US submission is based on data from more than 30,000 patients enrolled in all clinical studies, including the landmark SPORTIF program, involving 7,329 patients in total, examining the use of EXANTA as an alternative to warfarin for the prevention of stroke in patients with nonvalvular atrial fibrillation. In the clinical trial program for EXANTA, more than 17,000 patients received EXANTA. EXANTA is the first oral anticoagulant to reach late-stage clinical trials since the development of warfarin more than 50 years ago. The intended mechanism of action of EXANTA is to inhibit the activity of an enzyme called thrombin, which is critical to the final step in the formation of blood clots. Clinical studies with EXANTA utilize a fixed dose without coagulation monitoring. According to the American Heart Association, AF is found in about two million Americans and is a major risk factor for stroke. AF increases the risk of stroke five fold, accounting for about 15 percent of all strokes nationally. The stroke rate among patients with AF averages about five percent per year, rising to almost 25 percent for those over the age of 80. Older patients with risk factors such as hypertension or diabetes are at increased risk. Patients with AF tend to have more serious first strokes compared to those without AF. The number of patients with AF is likely to increase by 2.5 times during the next 50 years, reflecting the growing elderly population. In AF, the two small upper chambers of the heart, called the atria, quiver instead of beating effectively. Blood in these quivering chambers can pool and clot. If a section of the blood clot in the left atrium breaks off, travels to an artery in the brain and becomes lodged, a stroke may result. The results of several prospective randomized stroke prevention trials show that the relative risk of stroke in AF patients can be reduced by 62 percent using oral anticoagulant therapy. Treatment guidelines of the American College of Chest Physicians and the combined guidelines of the American College of Cardiology, American Heart Association and the European Society of Cardiology recommend the use of warfarin for most AF patients. However, many eligible patients are not receiving oral anticoagulant therapy. VTE, which includes deep-vein thrombosis (DVT) and pulmonary embolism (PE), is a term used to describe the formation of a clot in a vein. Each year in the United States, approximately two million people experience deep vein thrombosis, a condition where a clot forms in the deep veins, usually in the leg, impeding blood flow. Many conditions predispose patients to DVT and, according to the American Academy of Orthopedic Surgeons, patients undergoing the more than 300,000 knee replacement surgeries in the United States each year are a group at high risk of developing DVT. If a section of a clot in a patient with DVT breaks off, it may travel through the blood stream to the lungs and lodge in a pulmonary artery. This is known as pulmonary embolism, a serious condition that can cause death. Approximately 600,000 PEs occur each year in the United States, and more than 10 percent of patients who develop a PE die from it. The incidence of recurrent DVT or PE in patients treated with an anticoagulant for three months has been shown to range from 17.5 percent after two years to 25 percent after five years. These rates challenge the widely accepted use of short-course anticoagulation therapy in patients with symptomatic DVT. Siemens Medical Solutions Selects Agfa Healthcare as Preferred Supplier of Medical Accessories Siemens Medical Solutions and Agfa Healthcare have signed a three-year agreement positioning Agfa as a preferred supplier of hardcopy and computed radiography (CR) imaging solutions. Through this partnership, Siemens offers Agfa s Direct Thermal Imaging DRYSTAR diagnostic printers for all hardcopy solutions, including the new high-speed DRYSTAR 5500 printer and the new high-resolution DRYSTAR 4500M printer for digital mammography. Agfa's high-resolution printers also support both low and high throughput printing solutions for CR to its customers. Siemens also offers Agfa's CR products, including the new, high-capacity CR 75.0 and the CR 25.0. Siemens Accessory Solutions Group offers customers a variety of accessories and accessory packages to complement the full spectrum of Siemens clinical applications. Under the preferred vendor agreements, Agfa's products will be available as part of the Siemens total solutions package. Our partnership with Agfa supports our commitment to provide customers with total solutions, said Karin Finger, head of the Global Accessory Group, Siemens Medical Solutions. This agreement signifies our confidence in the relationship and the value of combining Agfa products with our imaging solutions. Through an agreement with a global imaging company such as Siemens, we are able to expand our potential customer base and increase awareness for our systems, said Paul De Kruyff, Global Director, Agfa OEM Business Group. It is very important to us to work with Siemens to provide one-stop solutions. Siemens works closely with all selected suppliers to ensure that these companies offer the highest quality products and reliable services. By ensuring that all technical and medical requirements are met, we aim to increase our customers efficiency and effectiveness, said Knut Fenner, Segment Manager, Accessory Solutions Group, Siemens Medical Solutions. Combining that with our integrated logistics, competitive pricing and one-stop shopping experience, we bring significant value-add to the purchasing process.