Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New targeting technology improves outcomes for patients with atrial fibrillation

19.07.2012
UCLA-UC San Diego study findings point to a doubling of success in treating the heart-rhythm disorder, which affects more than 5 million Americans

In a landmark study of atrial fibrillation, researchers from UCLA, UC San Diego and Indiana University report having found for the first time that these irregular heart rhythms are caused by small electrical sources within the heart, in the form of electrical spinning tops ("rotors") or focal beats.

Importantly, they found a way of detecting these key electrical sources and of shutting them down in minutes using a precisely targeted therapy with long-lasting results.

The team, which included cardiologists, physicists and bioengineers, reports the findings in the July 19 issue of the Journal of the American College of Cardiology as part of the CONFIRM trial (Conventional Ablation for Atrial Fibrillation With or Without Focal Impulse and Rotor Modulation).

Currently, many atrial fibrillation patients treated with standard therapies will experience a recurrence due to the difficulty of finding the arrhythmia's source. The new research will help cardiologists better target and treat arrhythmias.

The CONFIRM study examined 107 patients with atrial fibrillation who had been referred for a non-surgical catheter ablation procedure. During this procedure, doctors thread a wire with a metal-tipped catheter through the body, from a vein in the groin to the heart, to apply heat to the area of the heart producing the arrhythmia to stop it.

In one group of patients, the team used the new technique to help perform very small, precise burns — called focal impulse and rotor modulation, or FIRM — that were aimed directly at the fundamental source of the arrhythmia: the tiny electrical disturbances in the heart called focal beats or 'rotors' that look like mini-tornadoes or spinning tops. Rotors can be likened to an "eye of a storm" shown in this study to cause atrial fibrillation. Remarkably, this new procedure shut down or very significantly slowed atrial fibrillation in 86 percent of patients in an average of just 2.5 minutes.

As a comparison, conventional catheter procedures were performed in a second group of patients. Since this approach is less targeted, it involved hours of treatment over larger regions in the heart and often did not shut down the atrial fibrillation.

To track outcomes, patients received an implanted ECG monitor that very accurately assessed their heart rhythms over time. The researchers found that after two years, the FIRM-guided group had an 82.4 percent freedom from atrial fibrillation episodes, compared with only 44.9 percent freedom in the group that received standard therapy.

The new targeted method demonstrated an 86 percent improvement over the conventional method.

"We are very excited by this trial, which for the first time shows that atrial fibrillation is maintained by small electrical hotspots, where brief FIRM guided ablation can shut down the arrhythmia and bring the heart back to a normal rhythm after only minutes of ablation," said lead author Dr. Sanjiv Narayan, a professor of medicine at UC San Diego, visiting professor at the UCLA Cardiac Arrhythmia Center, and director of electrophysiology at the San Diego Veterans Affairs Medical Center.

"The results of this trial, with an 80 percent ablation success rate after a single procedure, are very gratifying," said study author Dr. Kalyanam Shivkumar, director of the UCLA Cardiac Arrhythmia Center and a professor of medicine and radiological sciences at UCLA. "This is the dawn of a new phase of managing this common arrhythmia that is mechanism-based."

The science behind this work was funded by grants to Dr. Narayan from the National Institutes of Health (NIH grant numbers: HL70529, HL83359, HL83359-S1, HL103800), including a grant awarded as part of the American Recovery and Reinvestment Act, and by the Doris Duke Charitable Foundations.

From UC San Diego: These discoveries, owned by the Regents of the University of California, were then licensed to a startup company, Topera Medical, which has recently obtained clearance from the Food and Drug Administration for the mapping system it developed from this early science, called RhythmView.

Narayan is a co-founder with equity interest in Topera. Study author Wouter-Jan Rappel from the UC San Diego Department of Theoretical Biological Physics holds equity interest in Topera. Study author Dr. Shivkumar of UCLA is an unpaid advisor to Topera. Dr. John Miller, chief of electrophysiology at Indiana University, has received modest consulting fees from Topera.

Additional study authors included Dr. David Krummen, associate professor of medicine and associate director of electrophysiology fellowship training at the UC San Diego School of Medicine and associate director of the San Diego Veterans Affairs Medical Center, and Paul Clopton from the San Diego Veterans Affairs Medical Center Department of Statistics. They have no financial disclosures.

Rachel Champeau | EurekAlert!
Further information:
http://www.mednet.ucla.edu

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>