By LARRY HAIMOVITCH
CD&D Contributing Editor
and DON LONG
CD&D National Editor

BOSTON – The 30th annual scientific sessions of the Heart Rhythm Society (HRS; Washington) took place here in May, with record attendance as the field of electrophysiology (EP) continues to ascend in importance in the healthcare world.

For the third consecutive year, HRS sponsored a two-day "AF Summit," which once again drew an overflow attendance and was chock full of the latest clinical data on this emerging field.

The importance of atrial fibrillation (AF) to the EP community cannot be overestimated. It is by far the most common arrhythmia treated and clearly is an area with the greatest opportunity to improve patient outcomes, yet remains incredibly frustrating because there are so many unanswered questions. This was exemplified by the title of one panel discussion, "Are We Better off than Four Years Ago: What is the Best Approach?"

The rising awareness of AF can be seen by the recent introduction of House Resolution 255, which called for a National Atrial Fibrillation Awareness Month in September. In strongly supporting this initiative, Mark Estes III, MD, president of HRS, said that "currently, less than 30% of AF patients receive the recommended treatment. Therefore, an AF Awareness Month will play an important role in not only raising awareness but also improving patient care and ultimately saving lives."

With the average age of an AF patient exceeding 70 and a rapidly aging global population, several speakers cautioned that AF could soon become an "epidemic." Many experts have predicted that between now and 2050, the prevalence or pool of AF patients will nearly triple.

With the success rate of anti-arrhythmic drugs widely estimated at well below 50%, catheter ablation of atrial fibrillation has become a very important weapon in the EP's armamentarium. There were no FDA-approved products in the category until late-February, when Biosense Webster (Diamond Bar, California), a Johnson & Johnson (New Brunswick, New Jersey) company attained clearance for its Navistar Thermocool catheter.

Despite the absence of approved devices, domestic AF ablations have approximately doubled in the past three to four years and are estimated at about 75,000 to 80,000 in the U.S. this year.

During a session titled "Critical Issues in AF Therapy," several speakers noted that the results of catheter ablation are improving but yet have room for much more improvement. For myriad reasons, the true "success rate" is difficult to pinpoint and far more significantly, the measures of success vary widely. This aspect was noted by several speakers, one who succinctly said "there is so much more truth to find out."

One consensus that has clearly emerged is that ablation of the pulmonary veins (PVs) is, in the words of Pierre Jais, MD, Haut-Leveque Hospital (Bordeaux Pessac, France), the "cornerstone" of catheter ablation. Jais said that is especially true for a paroxysmal (intermittent, typically early stage) AF. In addition, it is generally accepted that PV ablation using a standard point-to-point radio frequency (RF) catheter ablation is limited by the technical challenges of maintaining catheter stability and all too often results in the recurrence of AF due to the lack of lesion continuity.

There are several unresolved issues in the catheter ablation of the PVs: Two key ones are 1) What other areas of the heart need to be ablated to halt the AF?, and 2) Are there other approaches or energy sources that will buoy the results of PV ablation or isolation?

With regard to the first question, several speakers discussed in detail other ablation sites such as the ganglionic plexi (GPs or the autonomic nervous system) and complex fractionated atrial electrograms (CFAEs).

The latter are highly random and chaotic electrical signals in the atria that may be a source of origin or perpetuation of AF – they are extremely difficult to identify accurately by visual inspection alone. With the modest success of PV ablation alone, these two ablation sites are gaining favor in the EP community and in many institutions are becoming the standard of care in AF ablation.

The initial clinical results from adding these additional ablation strategies are positive. According to Warren Jackman, MD, of the University of Oklahoma Health Science Center (Oklahoma City), the addition of GPs to an AF ablation can boost the success rate up to an additional 20%. However, this strategy adds to an already long and complex procedure.

A study presented at a late breaking clinical trial session, which is called the Substrate versus Trigger Ablation for Reduction of Atrial Fibrillation (STAR-AF) trial, shed more light on this topic.

Sponsored by St. Jude Medical (St. Paul, Minnesota), STAR-AF was an open, randomized, prospective, multi-center clinical trial involving 108 patients, administered in several Canadian and European centers. Designed as a three-arm trial, it compared the generally accepted treatment approach of PVI, with CFAE guided therapy, and with a third arm that combined the two therapies.

The STAR-AF trial included patients with both symptomatic high burden paroxysmal (intermittent, but frequent and prolonged AF) and those with persistent AF. These two groups represent the largest subset of patients with AF. The study participants had previously been unresponsive to anti-arrhythmic medications. The primary endpoint of the trial was relief of AF episodes of 30 seconds duration or greater, up to 12 months after treatment.

Study results indicated that after one ablation procedure, a combination of PVI and CFAE guided therapy demonstrated significantly higher freedom from AF, at 74%, as compared to PVI alone at 47% and CFAE guided therapy alone at 29%. Importantly, 94% of patients who received the combination of these treatments remained off any anti-arrhythmic medications at the end of the 12-month follow-up period.

According to the principal investigator in the study, Atul Verma, MD, from the heart rhythm program at Southlake Regional Health Centre (Newmarket, Ontario), "pulmonary vein isolation has been the cornerstone of our ablation procedures, and in patients with very sporadic paroxysmal atrial fibrillation, I think it works pretty well, especially after a second procedure."

However, he went on to say that " ... once we start looking at the higher-burden atrial-fibrillation patient population, especially those with persistent atrial fibrillation or those with paroxysmal symptoms that last a long time or whose symptoms are very frequent ... pulmonary vein isolation is probably not enough."

Verma concluded that "while many unanswered questions remain about the origins of and best treatment options for AF, the results of STAR-AF indicate that perhaps traditional pathways are not the optimal ones. By mapping for the areas of CFAE during AF ablation, we have demonstrated an incremental benefit for patients who historically may have undergone only a PVI."

Commenting on the trial, Denis Gestin, president of the St. Jude Medical International Division, noted that "the results of the STAR-AF trial represent an important step toward understanding the best set of tools and therapies for treating cardiac arrhythmias, such as AF, and highlights St. Jude Medical's commitment to providing pioneering research to improve treatment of this condition."

With regard to the question of energy sources, D. Wyn Davies, MD, of St. Mary's Hospital (London), delivered a comprehensive talk on non-radio frequency energy sources such as cryothermia, laser, high intensity focused ultrasound, irreversible electroporation and others. According to Davies, the goal of AF ablation should be a "single shot" of energy, which ideally would create complete block of the AF and also could simplify and shorten the procedure.

The most commercially advanced of these devices is the CryoCath Arctic Front cryo balloon, which has a CE mark for the treatment of paroxysmal AF. It is being actively commercialized in Europe and over 5000 patients at more than 100 centers have been treated so far.

The results of its U.S. prospective randomized controlled pivotal trial, dubbed Sustained Treatment Of Paroxysmal Atrial Fibrillation (STOP AF) are expected to be announced sometime in 2H09. Medtronic (Minneapolis) placed a big bet on single-shot cryo PV ablation, purchasing CryoCath for nearly $400 million in late 2008.

An intriguing player in this space is CardioFocus (Marlborough, Massachusetts), whose tagline at its HRS exhibit was "See what you ablate, ablate what you see." This slogan refers to the unique and very useful capability of its catheter to view the ablation zone in the PVs in real-time with direct endoscopic visualization. In addition, cases have been performed, demonstrating direct lesion visualization in real-time.

Physicians who have seen both aspects of this visualization capability believe that it represents a huge advantage over traditional fluoroscopic imaging and also better than intracardiac echocardiography. It is the only ablation catheter that has this attribute.

An equally, if not more important aspect of the company's device is that its balloon, which delivers ablative laser energy at 980 nm, is "compliant," that is, it is soft and will fit into the hugely different shapes and sizes of the patient's pulmonary veins. In contrast, the CryoCath Arctic Front balloon is rigid and while it comes in two different sizes, will not fit well into all PVs. A non-compliant balloon may result in incomplete ablation in the PVs and allow for recurrence of the AF.

Although its clinical data is limited to 18 patients treated since early 2009, the CardioFocus device appears very promising, with a 95% success rate in chronic isolation at three months post-procedure. In addition, there were no clinical recurrences or adverse events. The success rate compares very favorably to 63% reported in the pivotal trial with the Thermocool catheter. The latter required using multiple procedures.

Vivek Reddy, MD, director of cardiac electrophysiology at the University of Miami Miller School of Medicine, presented initial data on this catheter's use at the Scripps Clinic (La Jolla, California) Percutaneous Catheter Ablation of Atrial Fibrillation conference in March and noted that the early human data from cases being performed at Homolka Hospital (Prague, Czech Republic) was very encouraging.

In an interview with Cardiovascular Devices & Drugs at HRS, Reddy said, "This is by far the most promising technology I have seen for AF catheter ablation. I really like both the direct visualization and the fully compliant balloon and I think it could ultimately be the big winner in this market."

The company, which has been venture capital-backed for several years, is seeking to gain CE-mark approval in the coming months and anticipates initiating a human clinical trial in the U.S. yet this year.

1st comprehensive guide on lead performance

A lead for a pacemaker or implantable cardioverter defibrillator (ICD) "isn't peanut butter."

Well, yes ... and no.

This simple assertion was one of the most important to come out of an early-morning HRS press conference presentation on pacemaker/ICD leads.

But such a statement, as offered by William Maisel, MD, of the Minneapolis Heart Institute and co-chair of the task force that developed the guidelines, isn't as straightforward as it seems.

Malfunctioning leads can be as dangerous, and just as fatal, as salmonella-infected batches of peanut butter. But you can't "recall" them the same way as you would peanut butter.

This latter point was Maisel's main emphasis, and the society is using the guidance to recommend, among other things, that the FDA reconvene its risk management communications advisory panel to develop a set of terms as better alternatives to the "recall" of faulty pacemaker/ICD leads.

The term, of course, appears to mandate the explant and return to the manufacturer of these components – when this is frequently not feasible – and when a particular lead of the batch may still be functioning as intended. And, whether or not explant is necessary, the word "recall" sets off alarm bells, creating considerable anxiety among patients.

The need for this revaluation of terminology was just one part of a general unveiling of a new guidance document – billed by HRS as the first-ever comprehensive guidance for these pacemaker/ICD components – developed in collaboration with the American College of Cardiology (Washington) and the American Heart Association (Dallas).

The need for stricter surveillance of these leads was highlighted most recently by the FDA's recall of the Sprint Fidelis leads made by Medtronic, because being prone to fracture. This prompted the usual spate of patient lawsuits and – more importantly for the overall field of device regulation in the U.S. – lawsuits continuing to challenge the FDA's right to pre-empt state laws concerning faulty devices.

(Medtronic recently won a dismissal of a series of those lawsuits, thus supporting the decision by the Supreme Court in Riegel v. Medtronic last year).

Asked by CD&D during the Q&A portion of the presentation whether the Fidelis malfunctions had been the sentinel occasion prompting the new guidance, N.A. Mark Estes, MD, of Tufts University School of Medicine and president of HRS, essentially shifted the answer away from blame on a single manufacturer.

He said that the emphasis should be on the overall sector, not any single product, and the need to improve lead performance and patient outcomes.

Responding to further questions from CD&D concerning how to characterize the extent of lead malfunctions, Robert Hauser, MD, of the Minneapolis Heart Institute and the other co-chair of the guidelines task force, said that after five years, 95% to 98% of the leads are functioning properly, and that the point of the new document is to push for the improved performance of these device components and enhance the transparency in their use for both patients and manufacturers.

Hauser, however, is one of the authors of a recent study reported in the HRS journal HeartRhythm, indicating that there could be a higher rate of failure for the Fidelis leads than previous studies indicate. That report showed that the incidence of failure in patients is significantly higher than what is found in the company's ongoing analysis of the leads, and that the Fidelis continues to function in only 88% of patients three years after being implanted

And one of the abstracts issued at the conference ("Assessment of Fidelis Lead Survival: A Large Single Center Experience) predicted "a disturbingly high failure rate of 10% at four years following lead implantation."

Whatever the rates of failures, they are not unexpected, given that a lead "may experience more than 500 million repetitive cardiac cycles during its lifetime," according to an HRS statement.

The exact method for notifying clinicians, regulators and patients concerning lead performance problems is hardly a simple matter, according to Maisel. He said that the use, or not, of the word recall, offers an array of legal implications and regulatory complications.

He said that its use has been shown oftentimes to lead to a "bad clinical decision," for instance when explant is not necessary and in some patients may result in post-surgical complications.

He added that there is a "feeling among physicians [it is] a bad word," and the society has found that "other words resonate equally — and as effectively."

"Safety alert" and "product danger alert" are among the alternative wordings suggested by the guidelines document.

But even to this he added a caveat: "Whether or not an alert is issued is a bit misleading; [a lead malfunction] is a continuum – there is no line where a product is bad or a product is good."

To begin the process of jumping through the required hoops and over the necessary hurdles, the FDA's advisory panel on risk communication should reconvene "to start the process to figure out exactly what steps will be necessary," he said.

Hauser said, that whatever the ultimate wording, "the language should be crafted to avoid unnecessary anxiety or inappropriate interventions." And he cited a recommendation in the guidelines that manufacturers should be required to provide standardized device performance reports semi annually in understandable ways."

Asked if changing the verbiage related to lead malfunctions would create more alerts, Maisel said that "more or fewer alerts" was not the main issue. The goal, he said, should be "improved product safety, improved patient safety, improved clinical outcomes."

The other recommendations of the guidance for the EP sector implanting these devices cover a range of issues. These include: pre-market evaluation, post-market monitoring; the threshold which should trigger action and communication once a performance malfunction is identified; the use of new remote monitoring technologies; the use of an already established ICD registry as a method of post-market surveillance; and appropriate protocols concerning clinical issues.

These latter recommendations relate to: informed consent; monitoring of device performance; clinical presentation of abnormal lead performance; clinical management when abnormal lead performance is suspected; considerations for pediatric patients; and clinical responsibilities for reporting suspected/definite lead problems.

The complete guidelines document was published in the June issue of the HeartRhythm Journal.

Updated guidance has detailed protocols for lead extractions

If the performance of leads used to implant pacemakers and implantable cardioverter defibrillators (ICDs) is a large problem requiring consistent protocols and better data transparency, the extraction of these components – and the potential patient risks involved – may be an even more difficult issue requiring tracking and evaluation. It is, essentially, surgery, with all the attendant risks.

Besides issuing the first-ever comprehensive guidelines concerning lead performance, the HRS also unveiled new guidelines, of the updated type, on extracting these leads, if absolutely required.

The guidelines emphasize the need for greater consistency in these procedures, greater numbers of procedures by clinicians performing them, improved protocols in follow-up care, and pathways for future device development for these surgeries.

Rather burdened with the lengthy title "Transvenous Lead Extraction: Heart Rhythm Society Expert Consensus on Facilities, Training, Indications, and Patient Management," the guidelines were presented by Bruce Wilkoff, MD, director of cardiac pacing and tachyarrhythmia devices at the Cleveland Clinic and an HRS officer, and Charles Love, MD, of the Division of Cardiovascular Medicine at Ohio State University (Columbus).

The presenters noted the increase in these extractions from just a very small number 20 to 30 years ago to an estimated 20,000 a year worldwide today, but a general scarcity of information concerning how many centers implanting CIDs (cardiovascular implantable devices) are well-equipped and having the necessary training and expertise to perform the lead extractions with good results.

The new statement updates a guideline issued by HRS in 2000, and Wilkoff said that it is a much more detailed attempt to outline the "tools, techniques and indications ... that will prepare physicians, medical teams and facilities to determine the most effective lead management solution for their patients and deliver the best possible care."

The presenters acknowledged that there is no good data concerning how many centers can do these extractions in an effective way, but Love told Medical Device Daily that his "ballpark" estimate of the U.S. centers well trained and prepared to perform these extractions would be "about 100." And he said that the guidelines should provide additional help not only to the prepared centers but also to those not well equipped to do extractions and so help them determine when a patient needs to be referred to qualified center.

The presenters also emphasized the need to begin building better registry information concerning the procedures.

They noted that Cook Medical (Bloomington, Indiana) some time ago had begun such a registry but discontinued the effort about 10 years ago. And Love said that Cook's efforts had been extremely helpful in pinpointing the various protocol areas required for developing the society's guidance documents.

Wilkoff said that the initial step in improving the broad understanding of how these procedures are being carried out should begin with documentation by individual facilities and local regions to provide "benchmarks" concerning the practice. And he said that "ultimately," national and international registries should be developed.

The presenters emphasized the need for clinician efficiency as the product of doing enough of these extractions and doing them frequently.

The document says that a research analysis of outcomes "suggests that the frequency of complete procedural success improves dramatically after the first 10-20 procedures have been performed. Even physicians with many years of experience have a reduced frequency of complete procedural success when 60 or fewer laser assisted lead extraction procedures were accomplished over the prior five years." And it notes "the steepest decline in complications over the first 30 cases."

Wilkoff, however, emphasized that these numbers are not hard-and-fast indicators of success in doing extractions, but instead that technical and clinical success should be defined by "outcomes."

He said, "Not all lead extractions are created equal," meaning that they vary greatly in complexity, and that "Volume is not the way you should measure this."

The key metric, he said, is where these procedures are done "repetitively ... but not hang our hats completely on a number."

Importantly, a primary recommendation of the guideline is that physicians "should only seek training and hospitals should only provide service when there is an ongoing commitment to a procedural volume adequate to maintain the skills of the physician and team. A sustained commitment to track outcomes of both device implantation and lead extraction is also essential."

Besides providing wording concerning the outcomes that define "technical and clinical success," the guideline addresses the following:

• Classification of complications.

• Personnel roles and responsibilities.

• Physician qualifications and training,

• Recommendations on minimum training volume, and facility and equipment requirements.

• Patient and procedure preparation,

• Indications for lead removal and transvenous lead extraction,.

• Technical and clinical evaluation of new techniques and tools.

• Recommendations for clinical evaluation of lead extraction devices.

The complete document guideline will be published in the July issue of HeartRhythm Journal, a publication of HRS.

Medtronic pacing system is MRI-safe

MRIs are safe ... almost all of the time.

But it's well-known that the strong magnetic fields of these machines can produce some rather unexpected and amazing effects, such as pulling or throwing loose metal instruments about the MRI room, occasionally causing injuries.

And there's one other thing: they can heat up implanted metal devices.

Rather significantly, the magnetic fields can heat up pacemakers, potentially turning their leads into hot tips which then ablate portions of the heart, death being the possible, though occasional, result.

"Every once in awhile there's going to be a disaster," said Wilkoff, presenting the results of a pivotal trial of a new MRI-safe pacemaker.

"Cooking the myocardium" is how he described what can happen when the leads of a standard pacemaker heat up during MRI, and he noted the increasing population of older people with pacemakers who also require assessment via this modality.

Other disastrous or near-disastrous effects of MRI for those with pacemakers may be that the devices are compromised so that they are unable to deliver therapy or they deliver unnecessary pacing. Thus, these patients are generally advised not to undergo what may be a rather necessary assessment.

The pacemaker studied in the trial is the EnRhthm MRI SureScan system from Medtronic, CE-marked but not yet approved by the FDA, noted Wilkoff, a Medtronic consultant helping to develop the system.

Wilkoff said that the increase in the use of pacemakers – "over the years, many millions implanted," he noted – and a continually growing number of these implantations in those over the age of 65 who may need MRI assessment. Thus, he said, "the indication for MRI doubles, the overlap of the two populations [with pacemaker/needing MRI] is enormous."

The pilot trial tracked 464 patients implanted at 41 centers in North America (U.S. and Canada), Europe and the Middle East, with enrollees randomized to either MRI or no MRI. Following implantation with pacemakers, the MRI group received various types of head and lumbar scans with 1.5 Tesla MRI machines.

Of this group, 444 patients were later followed, the follow-ups finding "no MRI-related complications or MRI-attributed sustained ventricular arrhythmias, asystole episodes, or pacemaker malfunctions."

There were some slight decreases in pacemaker sensing amplitudes in some devices. But, according to the study abstract: "There was no evidence of clinical (bradycardia or tachycardia), subclinical l(pacemaker performance) or technical (pacemaker or lead damage) adverse events observed in patients receiving an MRI."

Asked what constituted the changes in the pacemaker providing its safety in MRI, Wilkoff told CD&D that there was no one thing but rather "multiple small changes" in its "circuit, materials, geometry." The lead is still of metal material but with associated changes in the generator and the lead-generator architecture, he said.

In response to questions from CD&D, company representatives said that the enRhythm pacemaker is the only one yet designed for use with MRI and that it has been well received in the countries where it has been introduced.

The device utilizes "modified hardware to minimize the level of energy transmitted through the lead/device connection point." The device also includes a feature called SureScan that, "when programmed on before an MRI scan, temporarily alters the device's data collection and monitoring functions while still delivering asynchronous pacing if needed. The device also contains a radiopaque mark, viewable via X-ray, to indicate that the device is MR Conditional.

Filing for a PMA with the FDA, is being made "via a series of modules being submitted to FDA." The company predicts going before an FDA advisory panel, but the Medtronic representatives said it is not yet offering an estimate of regulatory approval or U.S. commercialization. They also said it is "premature" to state pricing.

Rather than specifying a marketing strategy for the system, they underlined the potential need for the device by that group identified by Wilkoff, those over 65 with a pacemaker and likely to require an MRI diagnostic procedure at some time, and that this type of pacemaker then would likely be used under the guidance of a physician.

In post-presentation questioning, Wilkoff said that the use of MRI for patients implanted with standard pacemakers can't be ruled out categorically but should be considered, based on a risk-benefit analysis.

Many ICD-implanted patients may need such assessments, he said, given ongoing chronic diseases, and that the risk of an MRI scan in these cases is less than that offered by avoiding a needed diagnostic. In such cases, he said, the condition of the patient and assessment of the pacemaker's operation, should receive close and continuous monitoring.

Medtronic also reported the first results from its OMNI Study, revealing that one out of six patients with implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillators (CRT-Ds) to prevent sudden cardiac arrest (SCA), received potentially life-saving medical therapy – either in the form of anti-tachycardia pacing (ATP) or a shock for dangerously fast heart rhythms – within a period of two years following their implant. Further, the study showed that patients received therapy at similar rates, regardless of whether they meet current medical society guidelines.

The OMNI Study is the first large-scale, longitudinal registry to follow nearly 3,000 real-world device patients. This analysis includes 1,620 patients who received devices for primary prevention of SCA, 993 of whom meet current guidelines, and 389 patients that do not. Patients among both groups received therapy at roughly the same rate:

Some 66% of patients among the guideline group, and 71% among the non-guideline group received ATP therapy. 34% percent of patients among the guideline group, and 29% among the non-guideline group received a shock

While OMNI researchers recognize that physicians may interpret the medical guidelines differently to drive individual treatment decisions for their patients, OMNI was not designed to assess why patients who meet or do not meet guidelines received devices from their doctors.

Also at HRS

• Biotronik (Berlin) reported REPLACE registry during a late breaking clinical trials session. According to the company, the REPLACE registry is a prospective, multi-center trial designed to provide physicians the data they need in advising patients and deciding on replacement of cardiac rhythm management devices.

The REPLACE registry collected data on patients who planned to have only their cardiac rhythm device, of any manufacturer, such as a pacemaker or implantable cardioverter defibrillator (ICD), replaced. Sponsored by Biotronik, the trial included 1,750 patients with devices from all cardiac rhythm management (CRM) industry manufacturers.

The trial was designed to define the complication and infection rates associated with all-cause device replacement. The trial also collected data on predefined major and minor complications, which could shape clinical practice guidelines for elective device replacements, the company noted.

"This prospective registry, due to the rigorous design, will become the gold standard for comparison," said Jeanne Poole, MD, director of electrophysiology at the University of Washington, and the national principal investigator of the REPLACE registry.

The REPLACE registry will provide the medical community exactly the information they have been looking for when considering the risks and benefits associated with performing device replacement procedures.

"Biotronik is committed to studies such as REPLACE that contribute valuable, patient-focused information to all parties concerned with improving patients' quality of life," said company president Jake Langer.

• Boston Scientific (Natick, Massachusetts) reported data from its ALTITUDE Clinical Science program that show real-word survival rates for implantable cardiac device patients exceeding rates from clinical trials. ALTITUDE analyzes outcomes data from patients monitored by the LATITUDE patient management system. Five-year survival rate data for patients using ICDs and cardiac resynchronization therapy defibrillators (CRT-Ds) were presented at HRS by Leslie Saxon, MD, chief of cardiovascular medicine at the Cardiovascular and Thoracic Institute of the University of Southern California (Los Angeles) and chairperson of the ALTITUDE physician panel.

Boston Scientific has enrolled more than 130,000 patients on the LATITUDE system since its introduction in 2006, making it the most rapidly adopted remote cardiac device monitoring system in the industry, according to the company. The LATITUDE system enables physicians to schedule remote follow-ups of implantable cardiac device patients to monitor specific device information and heart health status. The system can also detect clinical events between scheduled visits and send relevant data directly to physicians. This regular, in-home monitoring offers convenience and peace of mind for patients.

Findings presented yesterday from ALTITUDE, which analyzed nearly 86,000 patients monitored by the LATITUDE system, include: Five-year survival rates for ICD patients of up to 92%; five-year survival rates for CRT-D patients of up to 78%.

"In contrast to clinical trials, the ALTITUDE program analyzes device therapy in real-world practice and offers insights into clinical event rates and disease progression for extensive ICD and CRT-D patient populations," Saxon said. "This observational cohort study represents the largest cardiac device patient cohort to date and clearly shows survival rates exceed those reported in randomized trials."

• CardioNet (Conshohocken, Pennsylvania) reported the launch of SomNet, a new clinical indicator available in the company's existing Mobile Cardiac Outpatient Telemetry (MCOT) system. Because many patients with cardiac disorders also suffer from common sleep disorders like sleep apnea, CardioNet believes that SomNet has the potential to identify patients with a high likelihood of such sleep disorders by measuring cyclic variation of heart rate (CVHR), a rhythm that is caused by repeated arousals from sleep due to such disorders.

"There is a high prevalence of sleep disorders like sleep apnea in the cardiovascular and arrhythmia population," said CEO Randy Thurman. "The data collected by SomNet is extremely valuable information that can be captured from our existing MCOT ECG signal. If clinically appropriate, physicians may choose to refer patients with CVHR patterns to sleep centers for further diagnostic testing, to determine if they have sleep apnea or another serious sleep disorder."

In an 80-patient study, Phyllis Stein, PhD, research associate professor of medicine at Washington University School of Medicine (St. Louis), found that automated identification of clinically relevant CVHR is feasible using CardioNet's MCOT system. The study compared MCOT automatic analysis of CVHR patterns versus a human expert's direct analysis of plots of HR patterns for measuring clear (large amplitude) CVHR. Findings showed similar specificity and positive predictive value measures between MCOT and human expert analysis, with slightly lower sensitivity measures for the automated analysis.

• eCardio Diagnostics (Woodlands, Texas) reported the launch of its new Atrial Fibrillation Information System (AFIS). AFISis an informatics solution that presents a longitudinal view of atrial fibrillation and tachyarrhythmic patients for teaching, research or clinical management. It is the first comprehensive software application to gather all associated clinical information in one place for AF patient management.

Designed specifically to meet the needs of electrophysiologists in academic medicine, AFIS captures imaging, monitoring, procedural reports, clinic notes and patient history to provide clinicians with the most longitudinal data set on which to render treatment decisions.

• Endosense (Geneva, Switzerland) reported the release of acute clinical results from the TOCCATA (TOuCh+ for CATheter Ablation). The results of the 76-patient, multi-center study confirm the feasibility, safety and value of Endosense's TactiCath force-sensing ablation catheter during catheter ablation. The first and only force-sensing ablation catheter, TactiCath gives physicians a real-time, objective measure of contact force during the catheter ablation procedure. The TactiCath was granted the CE mark this month.

The TOCCATA trial was designed to evaluate the safety and value of force-sensing in the catheter ablation procedure. Conducted at eight centers in five countries, the study was led by principal investigator Karl-Heinz Kuck, MD, with participation from 20 additional highly experienced investigators. Enrollment in TOCCATA was completed in February, with a total of 76 patients (42 right SVT and 34 paroxysmal atrial fibrillation [AF]). Safety and treatment efficacy have been proven for the SVT group, which has reached the study endpoints. Data from the AF group is anticipated by the end of May.

During the study, operators were given full access to real-time force information during catheter ablation but were blinded to force information during force assessment. Key findings, extracted from 185 hours of force contact data, are the subject of two separate Heart Rhythm 2009 presentations by Dr. Kuck and TOCCATA investigator Dipen Shah, MD

• Hansen Medical (Mountain View California) showcased advancements to its Sensei Robotic Catheter System for electrophysiology (EP) procedures. The company demonstrated improvements in its user interface, catheter capabilities and design, and in imaging and mapping technology integration.

The company showed its new tactile vibration feature for its IntelliSense Fine Force Technology, which provides physicians with tactile feedback on proximal force for the first time with the Sensei system. As a result, physicians can now feel IntelliSense's force measurements through vibration of the Instinctive Motion Controller (IMC).

In addition, physicians saw a visual measure of force on the Sensei system's display monitor during EP procedures. With this new feature, physicians now have an improved tactile understanding of IntelliSense's measurements and force sensing during complex cardiac procedures. This advancement is important because a study suggests a link between the ability to measure force and the quality of electroanatomical maps.

Hansen Medical's technology is compatible with fluoroscopy, ultrasound, 3-D surface map and patient electroanatomical data. The two main components that comprise the Sensei system are the Artisan catheter and the ergonomically designed, remotely placed workstation. The physician workstation is adaptable to existing EP lab suites and imaging technologies and can be placed away from the field of direct radiation.

• NewCardio (Santa Clara, California), a cardiac diagnostic and services company, said it is introducing the NewCardio platform, QTinno and Visual3Dx at Heart Rhythm 2009. The company will be located at booth number 468 at the Boston Convention and Exhibition Center.

NewCardio said it believes that its QTinno, software-based, analytical technology is the industry's first solution for the reliable automated analysis of ECGs used to determine cardiac toxicity during drug development. Visual3Dx is designed to generate 3D information from the heart using standard 12-lead ECG data. It is expected to provide clinicians additional information on the extent and location of damage to the heart caused by a myocardial infarction to improve the speed and accuracy of diagnosis.

• TyRx (Monmouth, New Jersey), a developer of implantable medical-pharmaceutical devices, reported the initial, interim clinical results from its AigisRx Antibacterial Envelope Retrospective Registry.

Aigis is an anti-bacterial mesh envelope developed to deliver anti-microbial agents that help provide protection against infections associated with implanted pacemakers and cardioverter defibrillators. Aigis also securely holds a pacemaker or ICD in order to create a stable environment when implanted in the body.