June 2002  Clinical and Industry News

Waiting Best Strategy for Some Aneurysms Two new studies conclude stomach aneurysms do not require risky surgery right away, unless they have grown too big or are growing too rapidly. The findings confirm the conventional wisdom that surgery can be safely postponed until an abdominal aortic aneurysm reaches a diameter of 2.2 inches (5.5 cm). About 9,000 people die in the United States each year when their abdominal aortic aneurysm ruptures. In addition, 33,000 people are sent to the operating room to have their aneurysm repaired. But the surgery is risky. Between 1,400 and 2,800 patients die from the operation alone and doctors would like to delay the surgery until it is really necessary. Our ultimate goal is to repair the (aneurysm) that will burst and not others, said Dr. Frank A. Lederle of the Veterans Affairs Medical Centers in Minneapolis, leader of the first study. He and his colleagues randomly assigned people with an aneurysm to surgery or to a regimen where doctors simply checked on the size of the aneurysm every six months. At the start of the study, all of the aneurysms were between 1.6 inches and 2.1 inches (4.0 cm and 5.4 cm) in diameter. Once the artery increased to 2.2 inches (5.5 cm), or had grown significantly by at least 0.3 inch (0.7 cm) in six months or 0.4 inch (1.0 cm) in one year surgery was performed. Lederle and his colleagues found patients did not face a greater risk of death by waiting. After about 5 years, the fatality rate among the 569 patients who received immediate surgery was 3.0 percent versus a rate of 2.6 percent for the 567 in the watchful waiting group. "Survival is not improved by operating immediately on smaller aneurysms, the Lederle team said, even when operative mortality is low. The study was done at Veterans Affairs medical centers throughout the country, so nearly all the patients were men. Because women with abdominal aortic aneurysm(s) are older and appear to have a higher risk of rupture, higher rupture-related mortality, and higher mortality after elective repair, the researchers cautioned, the results of these trials may not be applicable to women. Yet the second study, involving both men and women from Britain, also found it was safe to wait. That team, led by Dr. J.T. Powell of the University Hospitals of Coventry and Warwickshire, treated 563 patients with surgery between 1991 and 1995. The remaining 527 had their aneurysms checked every six months with ultrasound. Through August 2001, the overall mortality rate between the two groups was similar. However, there were some interesting trends. The volunteers who received surgery tended to have a slightly higher mortality rate at the beginning of the study due to the risks of surgery. But as time passed, it was the people who had the operation who tended to live slightly longer, the Powell group found. The reason: people in the surgery group were more likely to quit smoking. The two studies have provided solid evidence that surveillance with imaging is a safe and reasonable treatment strategy for patients with abdominal aortic aneurysms between 4.0 and 5.4 cm (1.6 inches and 2.1 inches) in diameter, said Dr. Robert W. Thompson of the Washington University School of Medicine. Thompson warned that doctors must be vigilant if surgery is delayed because 50 to 80 percent of these patients can be expected to require surgical repair within several years. NIPRO APPALEAD by Nipro Medical Corporation NIPRO Medical Corporation has introduced the Appalead angiography guide wire. The Appalead features a Ni-Ti Alloy core wire. This new nickel titanium alloy provides outstanding kink resistance and 1:1 torque response. The hydrophilic polymer coating coupled with soft tip provides superior control and safety in tortuous anatomy. The Appalead is highly radiopaque and is available in many sizes and tips to enable safe and easy interventional procedures. For more information, contact NIPRO Medical Corporation at 1-888-647-7698 (Ext 246) or e-mail: tyamazaki@nipromed.com Two Paclitaxel-Eluting Coronary Stents From Cook Incorporated Enter New Advanced Trials In Europe Following up on the success of its ELUTES and ASPECT studies which were designed to study the effectiveness of Cook Incorporated’s new PTX Technology paclitaxel-eluting stents in reducing restenosis, two major new studies are now underway in Europe. The In-Stent ELUTES Trial is a multi-center, randomized controlled clinical trial evaluating the safety and efficacy of Cook’s paclitaxel-eluting V-Flex Plus PTX coronary stent in treating patients with in-stent restenosis. The study includes 22 centers throughout Europe and will enroll 600 patients in two treatment groups and a control group. Dr. Ivan DeScheerder of University Hospitals Leuven, Belgium, is the study’s principal investigator. The study’s nine-month primary effectiveness endpoints include in-stent minimum lumen diameter (MLD), percent diameter stenosis (DS) and late loss as determined by an independent angiographic core laboratory. Results from the study will be used to request additional approved indications for the V-Flex Plus PTX. Guidant Corporation announced that the first patient had been enrolled in the DELIVER II trial of Cook’s ACHIEVE Drug Eluting Coronary Stent System. This study, which includes a target enrollment of 1,500 patients at up to 100 centers outside the United States, will evaluate the benefit of the ACHIEVE Stent System in a broad population of patients, including high-risk patients and patients with complex coronary lesions, including in-stent restenosis. The new ACHIEVE Drug Eluting Coronary Stent System is a paclitaxel-coated stent manufactured by Cook that will be distributed worldwide exclusively by Guidant. On January 18th, Cook Incorporated became the first medical device manufacturer to file for regulatory approval anywhere in the world to market a paclitaxel-eluting coronary stent for treating restenosis when it filed for CE Mark approval for its V-Flex Plus PTX. The company is awaiting final approval on that application and will begin marketing the V-Flex Plus PTX to European institutions immediately after it receives CE Mark approval. Tools for Improving Nursing Workflow Responding to a nurse's need to better manage clinical workflow and improve efficiency, Siemens Medical Solutions presented its vision of Best Practice Integration for Critical Care at the American Association of Critical Care Nurses’ annual exposition in Atlanta, Georgia. Through a host of new innovations, Siemens aims to streamline information gathering and enhance clinical care: INFINITY EXPLORER: Provides access to patient information on a single display at the point of care. Infinity Explorer integrates patient vital signs with cardiac data, radiology images, lab test results, pharmacy information, clinical applications, and patient history into one comprehensive record. This record can then be accessed from any workstation throughout a hospital enterprise. INFINITY POCKET WINVIEW: An extension of the INFINITY Patient Monitoring System that allows clinicians to access patient waveforms from their pocket PCs, POCKET WINVIEW extends the reach of patient data to virtually anywhere the clinician may be, including an office across town or even at home. PICK AND GO Concept for Continuous Monitoring: PICK AND GO allows INFINITY monitors to move with a patient throughout the hospital, eliminating the need for a separate transport monitor. Wireless Monitoring: The need for patient information at a central location, and the fact that hardwire monitoring is difficult (if not impossible) in certain units, make wireless monitoring an important option in the critical care environment. Using a transmitter and access point, an INFINITY monitor can transmit patient information via a wireless network to wherever it is needed. DeRoyal Launches On-Line Custom Procedural Tray Management Tool The first comprehensive hospital web-based supply management software designed to control operating room custom procedural tray programs has been introduced by DeRoyal. The new healthcare software program, named CPT Optimizer, offers instant on-line access to information relating to inventory, quoting and tray standardization in five critical areas. They are: tray inventory, Internet quoting, functionally equivalent analysis (low-cost substitutions), best practice solutions, and procedure management. Judy Barkhurst, director of marketing, acute care business unit, said, the CPT Optimizer allows hospitals’ OR managers and materials managers to have the on-line capability to take total control in managing their custom procedural tray programs via the web. With a quick click of a mouse, they have real-time instant access to tray inventories, quotations and standardization all dedicated to significant bottom-line savings. While some of the CPT Optimizer key elements may be available piecemeal, we believe that CPT Optimizer’s breakthrough is that this is the first time that they have been bundled in the same software package. A live, demonstration version of CPT Optimizer is currently available at no cost on the DeRoyal website (www.deroyal.com). A Heart-Saving Gift from Easter Island It started out as an ineffective anti-fungal medication created from some Easter Island bacteria, but sirolimus is proving itself a wonder drug for people who have had heart transplants. Used since 1999 to prevent rejection of transplanted organs, researchers now believe sirolimus can protect the blood vessels of transplanted hearts the leading cause of heart transplant failure. Dr. Randall Morris of Stanford University has a primate study in hand that shows the same process that makes sirolimus a good immune suppressant also keeps the heart’s blood vessels clean. The drug works by blocking hormonal signals to immune cells, preventing them from receiving the word to attack the transplanted organ. Morris finds the drug also blocks hormonal signals to scar tissue cells. It has this sort of dual action that the other immunosuppressive drugs do not, he says. Morris conducted an experiment in which he transplanted aortas between 12 monkeys. Half the monkeys received treatments of sirolimus, and half did not. After 105 days, the animals receiving sirolimus had arteries that were nearly normal, while the aortas of the other monkeys were significantly clogged, Morris says. The maker of the drug, Wyeth-Amherst Laboratories, already has performed one human trial in Australia to test its usefulness in preventing arterial disease in transplant patients, says Dr. Joseph Camardo, the company’s senior vice president for clinical research and development. About 200 patients were given sirolimus following coronary artery grafts or heart transplants. It turned out after six months, you could see a significant difference, Camardo says. Sirolimus appears to prevent or at least slow down coronary vascular disease. Camardo says the company has yet to apply to the U.S. FDA for permission to use sirolimus in heart transplant patients because research on the drug’s possibilities is continuing. Sirolimus’ odyssey from Easter Island to America’s hospitals began with a Canadian geologic survey in the 1960s that led to the discovery of unusual bacteria in a soil of the South Pacific island. Wyeth-Amherst developed the bacteria into sirolimus, which the company thought might prove a good anti-bacterial or anti-fungal treatment. However, those uses were ineffective in early trials and the drug was shelved. In the late 1980s, however, researchers, including Morris, realized sirolimus had a chemical structure very similar to another drug being tested as a potential immune suppressant. Morris and others tested sirolimus, and found it kept the immune system from attacking transplanted organs without many of the toxic side effects found in other drugs. The drug, marketed under the trade name Rapamune, was approved by the FDA for use on transplant patients in 1999. Researchers have since found sirolimus also helps patients who have undergone angioplasty. FDA Approves the Medtronic CareLink Monitor and software for use with additional ICDs In addition to providing a way for cardiac patients and physicians to have virtual office visits, the Medtronic CareLink Network also is easy to use. After patients electronically transmitted information about their heart rhythm and implantable cardioverter defibrillator (ICD) using the Medtronic CareLink Monitor, 98 percent said the monitor was easy to use. Also, 97 percent of clinicians were satisfied with the Medtronic CareLink clinician website used to review and assess patient-transmitted data. CareLink significantly increases the convenience of communication between physicians and patients, said Dr. Mark Schoenfeld, associate clinical professor of medicine at Yale University School of medicine. With just a few website clicks after a patient downloads data from his or her implantable device at home or on vacation, I can access the same type of information I would collect during an office visit and quickly offer feedback to my patients. Of the 19 clinicians who used the Medtronic CareLink Network during the initial rollout, 97 percent said patient data received remotely allowed them to provide comparable care to an in-office visit, and 98 percent said the time to access the patient screen was excellent or very good. Medtronic has received U.S. FDA approval for use of the Medtronic CareLink Monitor and software with Medtronic GEM®, GEM® DR and GEM® III DR/VR ICDs. The Medtronic CareLink Network is intended to support a wide range of implanted cardiac devices, including Medtronic pacemakers, heart failure devices and monitoring/diagnostic devices as they become available following subsequent FDA approvals. Patients can view information about their devices and conditions on their own personalized website, and family members or other caregivers also can view this information if granted access by the patient. Clinicians access their patient’s data by logging onto the clinician website. First Implant of the IsoFlex Pacing Lead St. Jude Medical announced the world’s first implant of the IsoFlex pacing lead, the company’s newest passive fixation lead. St. Jude Medical has submitted the IsoFlex pacing lead family to the U.S. FDA for an investigational device exemption and to TUV for the CE Mark in Europe. Dr. Bernd Nowak of the Cardiovascular Center Bethanien, Frankfurt, Germany, performed the first IsoFlex lead implant in a 65-year old male patient with a sick sinus syndrome with an Identity XL DR Model 5376 pacemaker as part of a St. Jude Medical monitoring study. The patient is doing well and the device and lead system are performing as expected. The bipolar IsoFlex pacing lead has a small lead body, allowing it to be threaded through a thin 7F sheath. Its performance characteristics are designed to be similar to those of the Company’s Tendril® SDX active fixation pacing lead family. Clear Heart, Clear Mind Another risk factor for age-related dementia may have been uncovered. New research reveals that people with cardiovascular disease have an increased risk of developing dementia. It’s exciting to me because I’ve been saying this for years, and they’ve done a nice clinical study, says Dr. Michael Freedman, director of the division of geriatrics at New York University Medical Center. This is sort of how everybody has been treating patients, and it’s confirming all that we knew. The incidence of dementia in the United States is increasing as the population lives longer, yet little is known about its causes. Alzheimer’s is the most common form of dementia in older people, followed by vascular dementia. Scientists already knew treatment of hypertension seems to delay the onset of Alzheimer’s. Homocysteine, an amino acid found in the blood, is also a risk factor, and there’s been some evidence that lowering cholesterol can delay the start of dementia. The current study, presented at the annual meeting of the American Geriatric Society in Washington, D.C., was part of the larger Cardiovascular Health Study, which examined almost 6,000 people. The researchers, led by Dr. Anne Newman, a geriatrician and associate professor of medicine and epidemiology at the University of Pittsburgh’s School of Medicine, looked at a subset of that group: 3,602 people who had undergone additional cognitive testing. As it turned out, those with cardiovascular disease had about a 30 percent increased risk of dementia, a result only partially explained by stroke. Those with peripheral artery disease had the highest risk of dementia. The study did not look at interventions, but the implications are clear: treating cardiovascular disease may help prevent or delay the onset of different dementias. Although the relative risk was moderate, the high prevalence of cardiovascular disease, coupled with the high risk of dementia, in older adults would suggest that prevention of cardiovascular disease may be the most effective preventive measure we have for the prevention of dementia, Newman says. I see this in my office every day. A perfectly healthy 75-year-old with high blood pressure and cholesterol walks into my office. Do you treat it? Freedman asks. Just thinking logically, they’re 75 and perfectly healthy, we’ll just leave you alone. But, on the other hand, all the data is beginning to show that if you take a perfectly healthy 75-year-old and don’t do anything, they have an increased risk of Alzheimer’s by the time they’re 85. If you treat them, you may push off the onset until they’re in their 90s, and by then most of us aren’t around. This is another bit of evidence that it makes a difference. Medrad Expands Product Line By Adding Cardiac Magnetic Resonance Imaging Device Medrad, Inc. has signed a two-year agreement with W.L. Gore & Associates, Inc. to be the exclusive worldwide distributor of the Cardiovascular Array surface coil, the first magnetic resonance (MR) coil to combine a dedicated cardiac coil and a dedicated abdominal coil in a single device. Extending from the chest down to the bifurcation of the aorta in the pelvic region, the Cardiovascular Array makes it possible to image vascular disease throughout the entire torso in a single scan for the first time. The coil has received Food and Drug Administration clearance and will be available in the U.S. in July, with worldwide distribution rolled out over the next year. Since there is often a correlation between vascular disease in the heart and other critical vessel systems, a clear image of the entire area is critical for accurate diagnosis. Until now this required two separate scans, using valuable scanner time and increasing the likelihood of patient discomfort. The Cardiovascular Array is compatible with all phased array versions of the GE Signa® 1.5 T MR systems, and can be upgraded to be compatible with the eight-receiver scanners of the future. Its phased array design, a collection of antennae elements imbedded in the device that work with the scanner to produce a clear image, provides a clear, expanded image area for enhanced image and diagnosis. The coils are housed in flexible front-and-back panels that conform to different body sizes, delivering increased ease in patient positioning. Proprietary technology from Gore incorporates a radio frequency trap into the cable, eliminating the cumbersome external housing box required in the past. This is the second time that Medrad and Gore have partnered on a coil product; the Torso Array surface coil was released in November 2000, and has exceeded estimated sales targets. Coils are a significant part of Medrad’s product portfolio for the MR environment, and the company currently manufactures or distributes over 30 models that accommodate different body parts and scanners. New Cardiac Care Technologies Showcased by St. Jude Medical at the 23rd Annual North American Society of Pacing and Electrophysiology Scientific Sessions St. Jude Medical, Inc. displayed its broad suite of cardiac care technologies at the 23rd Annual Scientific Sessions of the North American Society of Pacing and Electrophysiology (NASPE) which ran from May 8“11 at the San Diego Convention Center in San Diego, California. The Downsized Atlas ICD and Riata ICD Lead Systems The St. Jude Medical Atlas DR/VR ICD family coupled with the Riata defibrillation lead provides physicians an ultra-small defibrillation system without any of the compromises traditionally associated with downsized products. At 42 joules (J) stored/36 joules (J) delivered, Atlas ICDs are the world’s most powerful rate-adaptive ICDs. Atlas delivers this powerful energy in a compact, sub-40 cc package while offering fast charge times, strong device longevity, and advanced Photon® Micro-based features. With their advanced functionality, Atlas ICDs can be prescribed for patients who need standard ICD therapy as well as those with high defibrillation thresholds (DFTs) who require more energy to terminate an arrhythmia. An ideal complement to the Atlas DR/VR ICD family is the newly released Riata family of active and passive fixation defibrillation leads, the world’s thinnest defibrillation leads. Riata leads provide physicians the best of both worlds by combining an ultra-thin lead body (used with an 8F sheath) for improved handling and implantation characteristics with a multi-cable design for increased strength and durability. The Identity Pacemaker Featuring AF Management A significant percentage of pacemaker patients suffer from atrial fibrillation, a cardiac disorder that affects over 5 million people worldwide. The St. Jude Medical Identity pacemaker family helps address this patient population through AF Management, featuring the clinically proven AF Suppression algorithm, stored intracardiac electrograms, and numerous AF-related diagnostics. Housecall ICD Transtelephonic Monitoring (TTM) System Dr. Thomas J. Dresing of the Cleveland Clinic presented data in support of St. Jude Medical’s Housecall ICD transtelephonic monitoring (TTM) system, a system that allows ICD patients to transmit diagnostic data through a standard telephone line. According to the findings from the major, 124-patient, yearlong study, 93-99% of patients indicated they were satisfied with the system from the standpoint of ease of use, timesaving, and confidence in the system. Researchers concluded that the Housecall TTM provided for frequent and comprehensive monitoring and reduced the frequency of outpatient visits. Patients can be reassured by an operator that the transmission was successful and have their diagnostic information interpreted immediately by a trained technician rather than having downloaded diagnostic information evaluated at a later time. Catheter-Based Solutions St. Jude Medical displayed its catheter systems, including the Livewire TC Bi-directional ablation catheter, designed for the radio frequency (RF) ablation of selected cardiac arrhythmias, the latest addition to the company’s broad portfolio of electrophysiology (EP) catheters. The new bi-directional tip provides increased flexibility to enable physicians to reach difficult endocardial locations. Other features offer precise catheter tip control and improved tissue contact. The company also offers the Seal-Away CS introducer kit, which allows for easier access to the coronary sinus (CS) during permanent lead placement for resynchronization therapy. These long peel-away sheaths with specialty curves help a physician quickly gain access to the coronary sinus and perform a CS venogram-facilitating visualization of the left ventricular vasculature for optimal lead placement. First Patients Enrolled in Clinical Trial of GuardWire Plus in Patients With Acute Myocardial Infarction In a study intended to further demonstrate the safety and effectiveness of balloon occlusion distal protection during vascular interventions, Medtronic announced the start of its EMERALD (Enhanced Myocardial Efficacy and Recovery by Aspiration of Liberalized Debris) trial. The study is specifically designed to compare results in patients with acute myocardial infarction (AMI), half of whom will be randomized to the new generation .028 inch GuardWire Plus Temporary Occlusion and Aspiration System, while the other half will receive conventional percutaneous interventional therapy (PCI) without embolic protection. Medtronic’s GuardWire Plus system has been available in its .036 configuration in the U.S. since last year. It was the first product to be approved for protection against potentially catastrophic major adverse clinical events (MACE) in patients undergoing diseased saphenous vein graft stenting. Studies have shown that distal embolization can lead to increased long-term mortality in such patients. Preventing embolization through the use of the .036 GuardWire Plus system has been shown to reduce morbidity and mortality by 42 percent in these patients. The GuardWire Plus system being tested in the EMERALD study includes three components: the .028 inch GuardWire Plus Balloon catheter, the MicroSeal® Adapter with E-Z Flator, and the Export® Aspiration Catheter. The balloon catheter will be deployed at the onset of the interventional procedure after crossing the lesion and then inflated to occlude the vessel. This prevents migration of embolic and thrombotic material that may dislodge during treatment of the lesion. The angioplasty balloon and/or stent systems are then advanced to the treatment site, where the dislodged particles should remain suspended in the occluded vessel. Upon completion of the stent placement or other interventional procedure, the Export Aspiration Catheter will be introduced, and the atherosclerotic particles removed. The GuardWire Plus balloon is then deflated and withdrawn. The EMERALD trial marks the first time a distal protection system will be evaluated for use during percutaneous intervention in patients who have experienced AMI. The EMERALD trial will be a multicenter, prospective, randomized study and will enroll a total of 500 patients. The .028 inch GuardWire Plus system is designed with a low profile and is designed to be small enough to accommodate vessel diameters from 2.0 mm to 5.0 mm. In addition, its smaller size may allow physicians to use the Export catheter for thrombus aspiration prior to, as well as after PTCA or stent deployment. Gregg W. Stone, MD, Lenox Hill Hospital, New York and the primary investigator for the EMERALD study, said the GuardWire Plus system may be beneficial for use in thrombus-laden lesions in vessels that are already occluded, such as those commonly found in AMI patients. The system is designed to provide enhanced protection of the distal myocardial bed and aspiration of all embolic debris. We believe this study will demonstrate that percutaneous intervention with the GuardWire Plus will significantly improve clinical outcomes in patients with AMI. Radiation Helps Keep Arteries Clear Long-Term Zapping the heart arteries with a dose of radiation after angioplasty seems to help keep them clear for up to 5 years, according to results of a new study. While previous studies indicated that radiation therapy results in early benefits, it was unclear if these effects would last, note Dr. Paul S. Teirstein from the Scripps Clinic in La Jolla, California and colleagues. In the study, patients who were given a dose of radiation inside their blood vessels during angioplasty were less likely to have their arteries narrow again 5 years later than those given angioplasty alone. In the longest follow-up of patients given radiation during angioplasty, the researchers compared outcomes over 5 years between 26 patients given radiation and 29 given angioplasty alone to treat restenosis. Teirstein’s team found that patients given radiation were 74% less likely to experience restenosis than those in the placebo group 6 months after the procedure, and were 48% less likely to have restenosis 5 years later. Teirstein noted that previous studies have shown that patients treated with radiation are at risk of a potentially life-threatening blood clot. However, in this study, nine people in the placebo group died compared with only five in the irradiated group, showing that irradiated patients may have no increased long-term risk of blood clots. Blood Pressure Medication is Not Administered to Best Protect Against MI, Stroke A majority of physicians tell patients to take their antihypertensive medication at a time of day that may not adequately protect them against potentially dangerous surges in blood pressure. According to a new survey by The Gallup Organization, little more than half of primary care physicians (PCPs) consider the body’s natural rhythms when prescribing treatments for high blood pressure, although more than 90 percent recognize these factors may put patients at a higher risk for heart attack and stroke during certain periods of the day. A growing body of evidence illustrates that the early-morning rise in blood pressure or a.m. surge experienced by most people may increase the risk of heart attack and stroke, particularly in individuals who suffer from hypertension. In fact, researchers have identified a 49 percent higher risk of stroke, a 40 percent higher risk of heart attack, and a 29 percent higher risk of cardiac death in the hours between 6 a.m. and noon. In the Gallup survey, slightly more than 80 percent of PCPs surveyed acknowledged that circadian rhythms put patients at the greatest risk for heart attack and stroke immediately upon awakening or in the morning. Yet, of the 88 percent who said they advise patients to take their antihypertensive medication at a certain time of day, more than two-thirds (68 percent) recommend in the morning or upon awakening as the optimal time. That dosing schedule does little to shield patients from morning circadian risks because blood pressure medication can take hours to reach peak concentrations. Nighttime dosing should be strongly considered because it allows blood pressure medication to reach peak concentrations as morning circadian variations begin to appear. But the survey showed only 21 percent of physicians are recommending evening or bedtime administration. A separate arm of the survey, which studied 600 randomly selected antihypertensive patients ages 50 and over, confirmed, and in some instances compounded, the findings of the physician poll. Chronotherapy, a relatively new approach to drug design and administration, may provide additional help to people with hypertension and other disorders. Chronotherapy coordinates medical treatment with the body’s circadian rhythms, and ensures the timing and amount of drug delivered optimizes the desired effects while minimizing adverse events.