CD&D National Editors
SAN FRANCISCO Remote monitoring of implanted cardiac devices is hot at least at the level of discussion during scientific conferences, if not at the level of reimbursement of such services. But one step at a time: This technology clearly is adding more evidence concerning efficacy, if not clear cost-effectiveness.
A clear emphasis at this year's scientific sessions of the Heart Rhythm Society (HRS; Washington) was that a physician shouldn't just implant a device and see the patient out the door. The physician needs to monitor the devices and even more closely monitor the patients implanted with the devices.
One of the major studies at the conference bannering the need for faster, more aggressive monitoring of implanted cardiac devices was the Pacemaker Remote Follow-up Evaluation and Review (PREFER) trial, comparing two types of technologies to track data gathered from pacemakers: in-person programming evaluations augmented by remote interrogation vs. in-person programming evaluations augmented by what was termed transtelephonic monitoring (TTM), also called TTM rhythm strip evaluations.
Medtronic (Minneapolis) was a beneficiary of the publicity coming out of the trial, via use of the company's CareLink Network, boosted further by the presentation of the study by Cleveland Clinic clinician Bruce Wilkoff, MD, the study's lead author. Wilkoff is director of cardiac pacing and tachyarrhythmia devices at the clinic.
CareLink monitoring superior
According to Wilkoff's report, remote monitoring with the CareLink Network was far superior to TTM evaluation in identifying what were termed "clinically actionable events," the trial's primary endpoint, which Wilkoff defined as "things that we could identify going on with the patient, being important to know" and then act upon.
At the end of 12-month follow-up, the remote monitoring method detected 60% of all clinically actionable events, Wilkoff said, while TTM detected just 2% of these.
TTM patients included those implanted with a dual-chamber device which transmitted 30-second ECG strips at two, four, six, eight and 10 months after enrollment, with in-office evaluations at six and 12 months; and also TTM patients with a single-chamber pacemaker, which transmitted data via TTM instead of an in-office evaluation at six months. There were a total of 296 patients in this group.
The other group the REMOTE group, of 605 enrollees and thus a roughly one-to-two ratio of a total of 897 patients were interrogated via the CareLink Network at three, six and nine months and in-office evaluation at 12 months.
David Steinhaus, MD, VP and medical director of the Cardiac Rhythm Disease Management business at Medtronic, said that "despite frequency, the limited point-in-time ECG information provided by TTM didn't uncover the potential for serious cardiac events as early as the more comprehensive data provided for the remote group."
Medtronic reported that CareLink introduced in the U.S. six years ago now follows 250,000 patients in 20 countries at nearly 2,400 clinics and "has registered 1 million patient data transmissions."
Medtronic touts the network as providing earlier signaling of potential problems, such as clots, arrhythmias and other events that may lead to more serious events, and Wilkoff agreed with this assessment. "There is a substantial increase in the shortening of the time for event-to-detection of event if you use remote interrogation," he said. He said that the next emphasis for studies of the technology will be a look at the actual clinical outcomes resulting from earlier detection and follow-on action.
Transoma touts Sleuth</P>
Remote monitoring systems in the future are likely to become seamless and automatic, but at present they still require a certain amount patient action and patient-provider interaction and activity.
With emphasis on that fact, Transoma (St. Paul, Minnesota) heretofore primarily focused on providing tiny implanted blood pressure monitors in animals for drug reactions presented a breakfast meeting during the HRS conference its new Sleuth implantable monitoring system, extolling its ability to provide continuous monitoring for diagnosis of syncope with little action required by the patient.
FDA-cleared in October 2007, the Sleuth is implanted in just a few minutes under local anesthetic and is now receiving roll-out by the company, Nestor Jaramillo, VP of sales and marketing, told CD&D. He said the company is looking to file with the FDA for other indications, with an advanced generation of the device, such as for the detection of AF.
Presenting much of the information about the Sleuth was Randy Lieberman, MD, of Heart Care Cardiology (Detroit), who billed Sleuth as very different from the "old paradigm" of remote monitoring which he said required active, rather than continuous, accessing of the monitored data by the physician.
Sleuth, he said, delivers the data continuously and updates the physician, when necessary, via fax or other message systems. And Lieberman was very deliberate in underlining the need for this type of monitoring, saying that syncope is too often over-looked. "It's absolutely amazing how we approach [this] problem, if we bury it under the carpet. Then [the patient] will have a stroke or wreck the car because we couldn't guess the moment when we should put the Holter [monitor] on."
While presenters referred to the Sleuth as completely automatic, Jaramillo told CD&D that at least one patient action is necessary: after recovering from a syncope, the patient pushes a button and the monitor then backs up and collects several minutes of data before the fainting spell and delivers it on.
Jarmillo said that Transoma is not positioning itself to compete against Medtronic in this sector, but simply to first become a participant in it, given the size of the market being continuously boosted by aging demographics.
CD&D asked one clinician leaving the breakfast session if all of this works as effectively and cost-effectively, as claimed by Transoma. "We'll see," she responded. "I'm doing a study."
Cell phone-fast a benefit
In another study presented at the conference focusing on what might be called "faster time to action," researchers reported data from the Synthesized Twelve-lead ST Monitoring & Real-time Tele-electrocardiography (ST SMART) study on the use of special ECG devices modified to wirelessly transmit an ECG reading to the hospital through mobile phone technology while continuously monitoring the patient's status and re-transmitting information to the hospital if changes were detect.
The devices were placed in all paramedic vehicles in Santa Cruz County, California, beginning in 2003.
The findings: Patients randomized to the experimental group with pre-hospital ECG cell phone transmission had an initial ECG reading 50 minutes earlier than patients randomized to the control group with their first ECG reading at the hospital.
In addition, patients who received a pre-hospital ECG had an average door-to-balloon time of 79 minutes, 37 minutes faster than those who did not receive a pre-hospital ECG.
Rolling out Vision 3D
In April the FDA approved the "first wave" of devices under Medtronic's Vision 3D portfolio, including wireless implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy-defibrillators (CRT-Ds), pacemakers and cardiac resynchronization therapy-pacemakers (CRT-Ps). But the company used one of the larger marketing splashes at the HRS meeting to introduce the new lines (see sidebar, page 11).
The portfolio's first ICD and CRT-D devices will be commercially available in the coming months, the company said. "We listened to our customers, and made key enhancements to all devices in four areas that we call Vision 3D fundamentals' proven shock reduction, therapy efficacy, disease management and remote patient care," Tracy McNulty, a Medtronic spokeswoman, said in an e-mail responding to questions from CD&D. "Vision 3D represents the first time in ICD/CRT-D history that a manufacturer has introduced multiple levels of products; Medtronic also was the first to do this in pacing products with the introduction of Thera, Prodigy and Preva pacemakers in 1996, and most recently continuing with the Adapta portfolio in 2006."
Vision 3D has been in development for about three years, McNulty told CD&D.
"With previous or competing devices, physicians may have had to make a choice between key features, but with Vision 3D, the fundamentals are standard across all devices," she said.
Medtronic said that in addition to other features, Vision 3D introduces "automaticity" with Complete Capture Management, designed to provide confidence in patients' safety by continuously and automatically adjusting to changing patient needs, according to Medtronic. Complete automaticity provides physicians flexibility during in-office device checks and may also reduce battery drain, the company said.
Previously, Capture Management was only available for one chamber of the heart (right atrium or left ventricle), McNulty said. Complete Capture Management captures three chambers of the heart the right atrium, and right and left ventricles, she said. Additionally, it automatically provides a daily device check, enabling remote follow up when used with the Medtronic CareLink network, she said.
Other Medtronic features of Vision 3D portfolio include:
• Conexus Wireless Telemetry is available on all Vision 3D ICDs and CRT-Ds. Through Conexus, patients' device and condition data are automatically transmitted to clinicians and accessible remotely and electronically via the secure Medtronic CareLink network. More than 250,000 patients at nearly 2,400 clinics in 20 countries are followed remotely on the CareLink network, according to the company.
• Medtronic's PainFREE strategy for shock reduction, including ATP (anti-tachycardia pacing) During Charging. Integrated into all Vision 3D ICDs and CRT-Ds, ATP During Charging automatically uses pacing pulses to painlessly stop fast, dangerous heartbeats, while concurrently preparing to deliver a shock if needed, with no delay, according to Medtronic.
• The company's Managed Ventricular Pacing mode, intended to allow doctors to reduce unnecessary pacing to the right ventricle, the heart's lower right chamber.
• OptiVol Fluid Status Monitoring, a Medtronic feature that measures intrathoracic impedance in heart failure patients. Using very low electrical pulses that travel across the thoracic cavity (the chest area encompassing the heart and lungs), the system is designed to measure the level of resistance to the electrical pulses, which indicates fluid levels. Used in combination with the company's Heart Failure Management Report, OptiVol's ability to manage fluid status over time can provide physicians with important insights in conjunction with ongoing monitoring of other patient symptoms, Medtronic said, for more timely interventions.
New branding for St. Jude
St. Jude Medical (St. Paul, Minnesota), though not matching Medtronic's bravura presence, was second-most-prominent at the meeting, using the sessions to unveil a new corporate identity the third such unveiling, following its presence also at the American Association of Thoracic Surgery (Beverly, Massachusetts) meeting in San Diego, and at EuroPCR in Barcelona, Spain, both also in May.
The new brand identity is designed to communicate the "mission to develop medical technology and services that put more control into the hands of those who treat cardiac, neurological and chronic pain patients, worldwide," the company said.
A new St. Jude logo consists of eight small squares organized into a larger square, with an unaligned ninth square in the middle. In a statement, the company said that the unaligned, center element represents the risks that are present in any medical procedure, while the organized exterior box is intended to represent the company's commitment to helping physicians control these risks. The new logo also takes a new color, green instead of blue, and includes a tagline below the company's name: "More control. Less risk."
Amy Jo Meyer, spokeswoman for St. Jude, told CD&D, "We haven't had a tagline for a number of years" so the new tagline isn't really a replacement.
"Customers count on us to help them attain the best possible patient outcomes by reducing as much risk as possible," said Daniel Starks, president/CEO and chairman of St. Jude. "This priority drives our innovation, our quality program, our clinical studies and our new product introductions. It has been a critical element of our success and makes us a different kind of partner for physicians." He added that the new brand identify "better symbolizes the intensity of our focus and our commitment to providing physicians with the medical technology and services they need to control risks wherever possible."
St. Jude noted its various developments in recent years, including the Unity device platform, designed for remote patient monitoring of all new pacemakers, ICDs and CRT devices; the Durata 7 Fr high-voltage lead; irrigated RF ablation systems and "enhanced" cardiac imaging with the EnSite system and its EnSite Fusion Registration Module designed to give physicians highly detailed views of the heart's anatomy; neurostimulation products including Eon Mini, a spinal cord stimulator for chronic pain; surgical products for treating heart valve disease, including the Epic Stented Tissue Valve with Linx AC technology designed to enhance the valve's durability; and cardiology products, including the Angio-Seal vascular closure device.
As a part of the re-branding, the company's website, www.sjm.com, also is undergoing a redesign, with updating over the coming months.
Four from Ablation Frontiers
Ablation Frontiers (Carlsbad, California) made four presentations at the HRS meeting concerning early results using its Catheter Ablation System, saying that the findings aligned well with each other and supported previous experience from the field.
The company's multi-electrode mapping and ablation catheters used in conjunction with its radiofrequency (RF) generator was the subject of four presentations. Three of these reports examined early outcomes using the ablation system to treat atrial fibrillation (AF) in procedures throughout Europe; the fourth focused on the feasibility phase for a U.S.-based clinical study.
"In more than 1,000 commercial cases in Europe our technology has been very safe, highly effective and reduced procedures to well under two hours. Our commercial experiences are nicely substantiated by the four presentations given at HRS," said Keegan Harper, CEO of Ablation Frontiers. "The results presented also align well with each other, with a total of 230 patients showing no adverse events, approximately 80% efficacy, and average procedure times ranging from 85 to 129 minutes."
The largest study, presented by Dr. Lam Dang of the Klinik Im Park (Zurich, Switzerland), included 132 patients with paroxysmal AF. Dang reported a procedure time of 129 +/- 36 minutes with no device-related complications.
At the time of presentation, 80% of patients with six-month follow-up were free from AF and had discontinued drug therapy.
Lucas Boersma of St. Antonius Hospital (Nieuwegein, the Netherlands) presented two abstracts that studied 85 patients with paroxysmal AF who were treated with the Ablation Frontiers system. These presentations showed a 100% acute success rate, no peri/post-procedure complications up to seven days, and procedure time of 85 +/- 33 minutes. Of those patients monitored at the six month follow-up date, 83% were free of AF and off anti-arrhythmic drugs.
A smaller study of 20 patients with permanent AF was presented by Gregory Michaud, MD, director of the Center for the Advanced Management of Atrial Fibrillation at Brigham and Women's Hospital (Boston). This data represented procedures performed by 12 first-time operators as part of the feasibility phase of a US clinical trial called TTOP-AF, or the Tailored Treatment of Permanent AF, which is currently enrolling patients. Michaud reported that 96 percent of patients experienced a procedural success rate with no complications reported. At six months follow up, 75% of patients were in sinus rhythm, free of AF.
After receiving early data from this group of patients, the FDA allowed commencement of the pivotal TTOP-AF trial in the U.S.
"These early reports are extremely promising," noted Boersma, "and we are hopeful that long-term data will maintain consistency with the results presented. As physicians, we are excited about the remarkably close alignment of these safety and efficacy outcomes, with greatly reduced procedure times, in both the paroxysmal and permanent AF populations."
In late 2006, Ablation Frontiers received the CE mark to begin marketing in the European Union with its portfolio of anatomical-based catheters and a multi-channel RF generator.
From balloons to robotics
A sampling of other product roll-outs indicates this meeting's technical diversity.
• Cook Medical (Bloomington, Indiana) introduced its Evolution-Shortie mechanical dilator sheath at the HRS meeting. Cook said the sheath set is a natural adjunct to its Evolution mechanical extraction sheath technology. The technology is designed for venous entry during cardiac lead extraction procedures, for use in patients requiring the percutaneous dilation of tissue surrounding cardiac leads, in-dwelling catheters and foreign objects.
Cook says the Evolution-Shortie offers "the same intuitive and well-received Evolution mechanical dilator system technology, with added features designed to simplify vessel access during the lead extraction procedure." The device employs a shorter length to enhance physician control and a specialized distal tip that enables physicians to succinctly negotiate through tough fibrous binding adhesions, according to the company.
"Physicians have historically been forced to rely on either laser powered or mechanical extraction sheaths for difficult vein entry maneuvers," said Barry Norlander, global marketing manager for Cook Vascular, the maker of both Evolution devices. "If vein access cannot be accomplished with an extraction sheath, the physician must decide to either abort the procedure or use a less-desirable alternate extraction approach. With the Evolution-Shortie, physicians have access to an advanced tool that allows for a more effective procedure, resulting in a significant reduction in time, effort, cost and inconvenience to the patient."
• Greatbatch (Clarence, New York) showcased its eM-able line of MRI Conditional technologies at the meeting. MRI Conditional products in Active Implantable Medical Devices (AIMDs) are a critical initiative for device manufacturers because an MRI is often the major diagnostic tool for patients, the company says. AIMD systems are targeted for use in the cardiac rhythm management and neuromodulation markets.
MRI Conditional AIMDs will keep the MRI diagnostic tool in the physician's hands after an implant allowing patients to receive the greatest possible level of care.
The technology is based on the company's U.S. patent providing it the exclusive right to incorporate band-stop filtering technology into an implantable medical lead. This technology attenuates MRI-specific RF frequencies during MRI scanning, thereby eliminating the potential for lead system heating.
Greatbatch said it is completing the development of its eM-able Brady (bradycardia) pacing lead, which incorporates the aforementioned technology and is expected to cross additional milestones this summer.
• Braemar (Minneapolis), a subsidiary of Biotel (Eagen, Minnesota) and a developer of ambulatory cardiac monitoring devices, introduced and showcased the DLL900, an advanced Holter monitor, at the conference. At 1.75 ounces, the new monitor is more compact and discrete than earlier models, according to Bramer, while still providing a large liquid crystal display and extended recording time of up to seven days. A newly designed, custom analog IC for signal acquisition is the technology platform for the advanced capabilities of the DL900.
Harry Strandquist, president/CEO of Braemar, said, "Our partners are in the process of integrating this new device into their ambulatory cardiac monitoring product lines."
The DL900 increases diagnostic yield and provides extended recording time of several days or more for clinical research applications. The device combines high-speed USB transfer with the ability to use a removable memory card. The DL900 provides high-resolution recordings as well as high sampling rate options suitable for both clinical and research applications. A programmable pacemaker detection capability provides the clinician with additional data.
Braemar manufactures ambulatory cardiac monitoring and other medical devices for its OEM partners.
• Hansen Medical (Mountain View, California) had a large presence at the HRS meeting, with 13 clinical presentations of its Sensei Robotic catheter system, enabling clinicians to place mapping catheters in hard-to-reach anatomical locations within the heart easily and accurately during complex cardiac arrhythmia procedures. The Sensei, compatible with fluoroscopy, ultrasound, 3-D surface map and patient electrocardiogram data, was FDA-cleared about a year ago.
"We continue to be pleased by the demand for our technology and the clinical experience gained with the Sensei system," said Frederic Moll, MD, co-founder and CEO of Hansen. "Due to the fact that several of our installed sites no longer require clinical support from us, we aren't able to track every case completed. However, we are aware of a minimum of 600 procedures performed using our system for remote navigation, and we are confident the adoption of this technology in the treatment of complex cardiac diseases will continue to grow."
According to the company, some clinicians using the robotic technology are reporting high levels of confidence and less operator fatigue. Additionally, it said that certain physicians in the European Union are able to combine the use of the Sensei system's remote navigation capability with irrigated catheters to deliver more effective therapy during complex cardiac procedures.
The CoHesion 3D Visualization Module, an integrated product that combines the 3-D visualization of the EnSite visualization system from St. Jude Medical with 3-D navigation from the Sensei system, has been released in the European Union.
Hansen said that FDA clearance for the integrated system is expected in mid-year.