Research presented last month at the annual scientific conference of the British Cardiovascular Society shows that many heart attack patients are more likely to survive if paramedics take them directly to specialist heart attack centers for emergency primary angioplasty, rather than local accident and emergency departments for traditional clot-busting (thrombolysis) treatment.

Dr Miles Dalby, a cardiology consultant at Harefield Hospital (Middlesex) and his colleagues compared the outcome of 180 patients who received direct primary angioplasty at Harefield to the outcome of 181 patients who received the thrombolysis treatment at district general hospitals in the preceding two years. The results showed that direct primary angioplasty with rapid arrival-to-treatment times had a significantly higher survival rate than thrombolysis.

Dalby said, "Patients who were taken directly to Harefield Hospital by paramedics for primary angioplasty had a very low 30-day mortality rate of less than 3%. This shows a very large and significant mortality benefit when compared to patients who received thrombolysis treatment. That patient group had a mortality rate of 9%."

The research highlighted the need for rapid treatment, showing that while a less than 3%, 30-day mortality rate for primary angioplasty was achieved when patients were taken directly to Harefield by ambulance, those who went to district general hospitals first and were later transferred to Harefield for primary angioplasty had a much higher mortality rate.

Dalby said that prompt treatment requires an exceptionally high level of commitment from the whole team: "During a heart attack, blood flow to the heart muscle is blocked …. The sooner the patient receives treatment enabling the blood flow to return to the coronary arteries, the less damage occurs … time is muscle."

Dalby continues: "We carried out nearly 300 emergency primary angioplasties with an average time of 24 minutes from when patients arrived at the Harefield to having the procedure and restoring blood flow to the heart. This makes our primary angioplasty service one of the fastest in the world."

For the past three years, Harefield Hospital has offered North West London residents fast access to specialist emergency care at the 24-hour Heart Attack Centre. Paramedics from the London Ambulance Service have undergone specialist training to identify patients whose lives could be saved by being transferred directly to Harefield. The ambulances are met by a specialist cardiology team and the patient is taken directly to the catheter labs, where primary angioplasty is carried out immediately.

Magnesium stents show biodegradability in four months

Biodegradable magnesium stents have been developed to treat blockages in coronary arteries which can degrade within four months and achieve the same results as conventional stents, conclude authors of an article published in the June edition of The Lancet. But both the article and an accompanying comment warn longer term follow-up of the patients fitted with biodegradable stents is needed.

Professor Raimund Erbel, Department of Cardiology, West German Heart Centre (Essen, Germany), and colleagues implanted 71 of the biodegradable magnesium stents in 63 patients in the PROGRESS-AMS clinical trial.

The researchers found that after 12 months, the stents were safe, with no incidence of stent thrombosis (clotting within the stent), heart attack or death in any of the patients. They found that the diameter of the blood vessel within the stent (in-stent acute gain) increased by an average of 1.41 mm. Whilst the stent struts disappear over time, ultrasound confirms they remain present but have been absorbed into the vessel walls, with the space left behind "filled in." The magnesium is eventually replaced by calcium and phosphorous through the body's natural processes.

However the trial also showed that angiographic restenosis (re-blocking of the artery) occurred in 47.5% of patients who received the biodegradable stents, and 27% needed target lesion vascularisation within 12 months due to recurrent ischaemia (lack of blood flow to the tissues).

The authors say that this study "showed that absorbable magnesium stents can be delivered and expanded at high pressure in artherosclerotic coronary arteries, providing good mechanical scaffolding and achieving a lumen enlargement similar to the immediate lumen gain obtained with conventional metallic stents."

The article says the new biodegradable stents overcome the limitations of conventional permanent stents namely that they can cause thrombosis many months after implantation and thus regular dual antiplatelet drug treatment such as aspirin and clopidogrel are required to prevent this occurring in patients with conventional stents fitted.

And drug-eluting stents have limitations because despite being able to achieve significant decreases in angiographic restenosis, they can cause hypersensitivity reactions and late-stent thrombosis, possibly because the drugs eluted hinder re-endothelialization (re-lining of the inside wall of the artery) of stent struts. Biodegradable stents are being analyzed in an attempt to avoid this problem.

The authors caution that studies with more patients and longer term follow-up are required to confirm the safety of biodegradable magnesium stents.

They say: "For a new product such as absorbable metal stents, four months of angiographical study and 12 months clinical follow-up might be insufficient to capture all the potential late events and complications."

And they conclude that the study shows that biodegradable magnesium stents can achieve an immediate angiographic result similar to the result of other metal stents and can be safely degraded after four months. Modifications of stent characteristics with prolonged degradation and drug elution are currently in development."

In an accompanying comment, Dr John Ormiston and Dr Mark Webster, Mercy Angiography and Auckland City Hospital (Auckland, New Zealand), say: "Bioabsorbable stents are in an early stage of development but hold considerable promise for overcoming many of the limitations of permanent metallic implants."

They add: "The initial patients treated with these devices will need to be followed up closely and for a long time. Whether bioabsorbable stents signal the threshold of a new era for percutaneous coronary intervention is yet to unfold."

Tryton'sSide-Branch stent featured in live studies

Tryton Medical (Newton, Massachusetts) reported marking "new milestones" in stent technology by a global demonstration of how the firm's Side-Branch Stent offers "unparalleled ease of use and the best option to safely and definitively treat bifurcation lesions."

Tryton transmitted a live satellite feed of a successful clinical case to an audience of interventional cardiologists at TCT Asia 2007 in Seoul, Korea, performed by Robert van Geuns, MD, PhD, a cardiologist at the Thoraxcenter of Erasmus Medical Center (Rotterdam, the Netherlands).

Patrick Serruys, MD, head of the department of interventional cardiology at the Thoraxcenter, moderated the event.

"This technology has the capacity to redefine the treatment of bifurcation lesions and resolve a frequent dilemma of the interventional cardiologist," Serruys said.

The Side-Branch Stent also was featured at the American College of Cardiology's i2 Summit in New Orleans in March, where a live satellite feed of a clinical case performed by George Sianos, MD, senior interventionalist at the Thoraxcenter, was transmitted to demonstrate the ease of use and angiographic results that can be achieved by using the Tryton stent.

Another live case was performed in front of 1,000 interventional cardiologists at the Joint Interventional Meeting (JIM 2007) in Rome.

The company said that every year, more than half a million bifurcation coronary lesions are "sub-optimally treated, as no commercially available optimized solution exists for treating bifurcation lesions." As a result, it said cardiologists "are forced to use a provisional strategy which avoids the deployment of a second stent — leaving the side branch vulnerable to thrombosis and restenosis."

Enrollment is completed In Olympia registry's Two phases

Boston Scientific (Natick, Massachusetts) said it has completed enrollment in the European and Intercontinental phases (II and III) of its Taxus Olympia registry, bringing the total number of current patients to more than 23,000.

The registry is designed to evaluate the safety and performance of the company's second-generation, Taxus Liberte drug-eluting coronary stent (DES) in a real-world setting. The company said that Olympia is the world's largest DES registry and that it plans to enroll at least 27,000 patients treated for complex coronary lesions at more than 400 centers worldwide.

"The size of the Olympia registry is truly unprecedented in the DES field and will yield invaluable real-world information to the benefit of interventional cardiologists and those patients who suffer from cardiovascular disease," said Martyn Thomas, MD, director of invasive cardiology at Kings College Hospital (London) and one of the coordinating investigators of the registry.

The multi-center, prospective, observational registry will evaluate a variety of safety and performance measures, including the rate of repeat procedures (target lesion revascularization) and major adverse cardiac events. Sub-analyses will be performed on complex patient groups such as diabetics, patients with multi-vessel disease, in-stent restenosis or a prior history of heart attack.

The Olympia registry is enrolling patients in multiple phases, corresponding to the commercial introduction of the Taxus Liberte stent system in different regions of the world. The initial, transitional phase enrolled 529 patients from a limited number of international markets in which Taxus Liberte was commercially available. The Phase I enrollment consisted of diverse and high-risk populations (including 50% diabetics, 49% multi-vessel disease, 40% small vessels and 48% complex lesions defined as B2/C).

Twelve-month results from Olympia Phase I were reported at last fall's Transcatheter Cardiovascular Therapeutics scientific symposium in Washington. The results demonstrated an overall Taxus Liberte stent-related cardiac event rate of 3.7%, including myocardial infarction (1.4%), and Taxus Liberte stent-related reintervention of the target vessel (1.9%), with an overall cardiac death rate of 1.5%. The final phase of the registry — phase IV — will enroll U.S. patients, following regulatory approval.

The Taxus Liberte DES is the second generation to Boston Scientific's Taxus Express2 coronary stent system.

Boston Scientific also reported last month that it has launched its Taxus Express2 paclitaxel-eluting stent system in Japan. The product was approved by the Japanese Ministry of Health, Labor and Welfare this past March and reimbursement, granted by the National Health Insurance System, took effect May 1.

Sorin releases its Reply next-generation pacemakers

Sorin Group (Milan, Italy) reported European market release of its next-generation Reply pacemakers, calling them the world's smallest dual-chamber pacemakers, at 8 cc. The Reply pacemakers integrate Sorin's SafeR pacing mode, which constantly monitors the patient's natural cardiac activity and reduces the amount of pacing delivered to the right ventricle, thereby promoting natural cardiac function.

Regulatory clearance in the U.S. and Japan is expected in early 2008.

Sorin said delivering unnecessary pacing to the right ventricle has been shown to "significantly enhance" the risk of patients developing heart failure and atrial fibrillation.

It said SafeR reduces pacing in the ventricle to 0.1% in patients without heart block. "Furthermore, recently published results have shown that patients with different degrees of heart block may also benefit from this pacing mode."

Sorin said that SafeR technology builds on its AAIsafeR mode, the first pacing mode designed to limit unnecessary ventricular pacing that was available in a pacemaker.

AAIsafeR was first launched in September 2003 in Europe and received FDA approval in May 2005.

In addition to SafeR, the Reply pacemakers bring together automatic features that offer easier patient management by streamlining device checks. Because all programming data needed for follow-up can be obtained from one touch on the programmer's screen, up to 25% of follow-up time can be saved, the company said.

Sorin, Mayo in collaboration for collapsible heart valve implant

Drago Cerchiari, CEO of the Sorin Group (Milan, Italy) and Mayo Clinic (Rochester, Minnesota) said they have signed a three-year agreement to collaborate in research efforts in the development of an aortic valve-replacement procedure that uses a collapsible heart valve implanted in a beating heart.

The collapsible heart valve would be implanted through a small incision in the apex of the heart, would be minimally invasive for the patient and would not require the heart lung machine, according to the companies. Thus, some patients who today cannot undergo a valve-replacement procedure either for advanced age or other medical reasons could still benefit from a life-saving, heart valve implant. This would represent a sizeable increase in the population eligible for valve replacements, the companies noted.

The new venture will use Sorin's new sutureless collapsible heart valve, which the company said has already been successfully implanted in man. The Sorin valve itself has nearly two decades of proven clinical excellence, according to the company.

Sorin and Mayo said they will not only develop the therapy itself but also the ancillary instruments needed for the successful execution of the implant and delivery of the valve. Once the implantation procedure is ready, Mayo said it would participate in U.S. clinical trials.

Franco Vallana, Sorin Group chief scientific officer, said Sorin's "know-how combined with Mayo's surgical expertise will ensure the successful outcome of our collaboration and will allow us to bring this new life-saving therapy to market as quickly as possible."

Sorin offers therapies for cardiac rhythm dysfunctions, interventional cardiology and the treatment of chronic kidney diseases.

FDA okays Angioblast stem cell trial for heart attack

Mesoblast (Melbourne, Australia), an adult stem-cell company, reported FDA clearance of its Investigational New Drug (IND) submission of its U.S.-based sister company, Angioblast Systems (New York), to commence a Phase II clinical trial of its allogeneic, or off-the-shelf adult stem cells for patients with heart attacks.

The trial will be based at the Texas Heart Institute (Houston) and follow a similar protocol as that used by the same investigators in pre-clinical studies for the IND submission. These showed that implantation of the allogeneic stem cells by catheter into damaged heart muscle resulted in "significant improvement" in heart function and reduction in congestive heart failure, the company said.

The Phase II trial will be the first to test an allogeneic stem cell product injected by catheter into heart muscle damaged by a recent heart attack. It will use the latest-generation catheters provided through Angioblast's ongoing relationship with the Cordis (Miami Lakes, Florida) and Biosense Webster (Diamond Bar, California), both Johnson & Johnson (New Brunswick, New Jersey) companies.

The commercial strategy for Mesoblast and Angioblast is to generate high-margin stem cell products obtained from a single donor, expanded, frozen and then used in thousands of unrelated, or allogeneic, recipients as needed.

Companies report gaining CE mark approvals

Several cardiovascular device firms reported receiving CE-mark approvals this past month.

• Cardiocom (Minneapolis), a maker of remote patient monitoring equipment and disease management software, said it has obtained CE-marking and launched its products in the European market.

The company said it has formed several distribution relationships in the UK, where the government is providing "significant funding" for telehealth solutions to meet the needs of an aging population.

The company will provide its partners with the Commander, Commander Cellular and AutoLink monitoring and alert products. The company's GlucoCom division will supply blood glucose monitoring supplies for diabetic patients.

Cardiocom said its UK partners would provide nurse call center services for daily monitoring of patient biometric data, health status and compliance using the company's web-based OmniVisor Pro patient management software system.

• Stereotaxis (St. Louis) reported that its partnered magnetic irrigated ablation catheter has received CE-marking and will be available in Europe in the near future.

In a statement, the company said the catheter, which gives physicians the ability to deliver high-power ablations for the treatment of complex arrhythmias such as atrial fibrillation and ventricular tachycardia, is expected to "further increase utilization in existing European sites and stimulate new system sales in the second half of 2007 and beyond."

• St. Jude Medical (St. Paul, Minnesota) reported expanded European CE-mark approval to include the Therapy Cool Path irrigated ablation catheter with bi-directional steering for use in ablation procedures to treat abnormal heart rhythms.

The company said the catheter is the first open-irrigated ablation catheter to provide bi-directional steering, a feature designed to help physicians maneuver the catheter in difficult areas of the heart and perform complex ablations more efficiently.

The catheter is produced by Irvine Biomedical (Irvine, California), a St. Jude business.

St. Jude also reported European CE-Mark approval of its first wireless devices to treat patients with heart failure and with potentially lethal heart arrythmias.

The Promote RF CRT-D (cardiac resynchronization therapy defibrillator) and Current RF ICD (implantable cardioverter-defibrillator) feature radio frequency (RF) telemetry for wireless communication with programmers used by physicians to interrogate and program devices.

• CoreValve (Irvine, California) said it has received the CE mark for its CoreValve Percutaneous ReValving System for treatment of high-risk patients. The ReValving System consists of a porcine pericardial tissue valve mounted in a self-expanding multi-level frame, which is permanently implanted over the diseased aortic heart valve by an 18 Fr-sized catheter.

The ReValving System procedure is intended to avoid open-heart surgery. It can be performed in a cardiac cath lab just like angioplasty and stenting, which, according to the company, may result in less patient trauma and offer "substantial cost savings" to the healthcare system.