AHA Scientific Sessions 2013: Highlights

Compiled by Jodie Elrod
Compiled by Jodie Elrod

Did you miss the American Heart Association’s Scientific Sessions 2013? This year’s sessions were held November 16–20 in Dallas. Below are a few of the clinical news highlights from the conference.

Late Breaking Clinical Trial Results Show Significant Delay in Atrial Fibrillation Disease Progression with Medtronic-Exclusive Pacing Features

New research shows that Medtronic, Inc. pacemakers with enhanced pacing features have the ability to slow the progression of atrial fibrillation (AF) in patients with bradycardia.

Presented as a late breaking clinical trial at the American Heart Association’s Scientific Sessions 2013, the MINERVA (MINimizE Right Ventricular pacing to prevent Atrial fibrillation and heart failure) study found that Medtronic pacemakers with atrial antitachycardia pacing (Reactive ATP), managed ventricular pacing (MVP®) and atrial intervention features were able to significantly decrease the incidence of mortality, cardiovascular hospitalizations or permanent AF at two years compared to pacemakers without these features. The effects of these features were most evident by a significant delay in the progression of atrial tachyarrhythmias to permanent AF, with a 61 percent relative risk reduction at two years.

“By addressing atrial fibrillation, which is the most common cardiac arrhythmia encountered in clinical practice, our study is the first to demonstrate that pacemakers with enhanced pacing features can significantly reduce the progression of this dangerous condition,” said Luigi Padeletti, professor of cardiology at the University of Florence, Florence, Italy, and principal investigator of the MINERVA study. “We know that AF has been associated with a higher risk of heart failure, stroke and death, so slowing down the progression of this disease may help reduce a patient’s risk of suffering these life-threatening conditions.”

The randomized and prospective MINERVA study evaluated the effects of three pacing modalities in 1,166 patients across 63 centers in Europe, the Middle East and Asia:

  • MVP, which promotes physiologic heart rhythms, thereby reducing the risks associated with unnecessary pacing in the right ventricle.
  • Atrial Intervention Pacing, atrial overdrive pacing designed to counteract potential atrial tachyarrhythmia initiating events.
  • Reactive ATP, which paces during atrial tachyarrhythmia intending to restore sinus rhythm.

The study’s primary objective was to evaluate whether the combination of these features reduces the composite incidence of mortality, cardiovascular hospitalizations or permanent AF at two years compared to standard pacing. Enrolled patients had standard indications for dual-chamber pacing and prior atrial tachyarrhythmias and were without complete heart block or permanent AF. The study found that DDDRP (dual chamber pacing with rate response and antitachycardia pacing) +MVP patients experienced a 26 percent reduced incidence (p=0.04) of the composite endpoint compared to standard paced patients. The effects of DDDRP+MVP were primarily driven by the 61 percent relative risk reduction in the progression to permanent AF (p=0.004).

Delays in AF progression were noted by significant reductions with DDDRP+MVP in the risk of AF episodes lasting longer than one day and persistent AF episodes. Impact to expensive health care utilizations was also observed by a 52 percent relative reduction in AF-related hospitalizations and emergency room visits (p<0.0001).

“This is the first study to show that using these enhanced pacing features in combination not only delays the AF disease progression, but also has an impact on health care utilization,” said Giuseppe Boriani, MD, Institute of Cardiology at the University of Bologna, Bologna, Italy, lead author and presenter of the MINERVA study at the meeting. “Based on this compelling evidence, an update of society guidelines should be considered.”

The MVP and Reactive ATP algorithms evaluated in the MINERVA study are exclusively available on the Medtronic Advisa and Revo MRI SureScan pacing systems.

In collaboration with leading clinicians, researchers and scientists worldwide, Medtronic offers the broadest range of innovative medical technology for the interventional and surgical treatment of cardiovascular disease and cardiac arrhythmias. The company strives to offer products and services that deliver clinical and economic value to healthcare consumers and providers around the world.

About Medtronic

Medtronic, Inc. (www.medtronic.com), headquartered in Minneapolis, is the global leader in medical technology - alleviating pain, restoring health, and extending life for millions of people around the world. 

LINC Study Reinforces the Safety and Effectiveness of the LUCAS Chest Compression System

Physio-Control, the world leader in emergency medical response technologies, announced that the comprehensive results of the LUCAS in Cardiac Arrest (LINC) clinical trial have been published in the prestigious Journal of the American Medical Association (JAMA). The article details results of this large randomized trial comparing resuscitation with the LUCAS® Chest Compression System with high-quality manual chest compressions in cardiac arrest patients. It shows use of the device to be safe and effective and includes data suggesting good neurological outcomes in patients treated with LUCAS. The article coincides with the Resuscitation Science Symposium (ReSS) held at the American Heart Association 2013 Scientific Sessions, where the study’s lead author, Prof. Sten Rubertsson, MD, PhD, Uppsala University, Sweden, presented the results of the per protocol analysis of data from the trial.

The publication expands on the LINC results presented at the European Society of Cardiology Congress in September, where neurological outcomes, measured using Cerebral Performance Category (CPC) scores were shown to be very good in both groups. In the detailed results described in the article, trends toward better neurological outcomes in the LUCAS group can be found. Across the time points, consistently more patients in the LUCAS group had a CPC score of 1 (good cerebral performance) and consistently fewer patients treated with LUCAS had a CPC score of 3-4 (severe cerebral disability/comatose or vegetative state).

“Surviving sudden cardiac arrest, by itself, is not enough. The real measure of a successful outcome is if the patient can return to a good quality of life,” said Brian Webster, president and CEO, Physio-Control. “We are very encouraged by the good neurological outcomes in the patients treated with LUCAS. It serves as the highest level of scientific evidence in support of the safe and effective use of LUCAS.”

The study is published in JAMA, an international peer-reviewed general medical journal and the most widely circulated medical journal in the world. It adds to over 100 publications about the safety, efficacy and practical benefits of LUCAS.

“The LINC trial is the largest randomized trial published on mechanical CPR and one of the largest randomized trials in pre-hospital cardiac arrest,” said Erik von Schenck, vice president, CPR Products, Physio-Control. “It marks over five years of research and the involvement of more than 2,500 patients, 700 emergency medical service providers and 1,500 hospital staff. We are delighted the LUCAS device worked effectively and reliably, and was highly appreciated by the users.”

About Sudden Cardiac Arrest and LUCAS Chest Compression System

Sudden cardiac arrest is one of the most common causes of death in the Western World, and may hit young as well as elderly people unexpectedly. Uninterrupted and effective chest compressions are key for survival and outcomes, but exhausting and difficult to provide consistently and safely manually. The LUCAS Chest Compression System is a medical device that assists emergency care personnel in maintaining life-sustaining blood circulation to the brain and heart in sudden cardiac arrest patients. It provides consistent and effective chest compressions, designed according to the European Resuscitation Council and American Heart Association Guidelines for CPR (cardiopulmonary resuscitation). LUCAS is simple to use, applied within seconds and feasible for use in a majority of cardiac arrest patients in most situations. LUCAS has also been used to provide life-sustaining circulation in arrest patients either during simultaneous percutaneous coronary intervention or as a bridge to other therapies. LUCAS was launched in 2003 and is today available in over 40 markets globally.

About Physio-Control

Physio-Control, Inc. is headquartered in Redmond, Washington. The company operates in over 100 countries and is the world’s leading provider of professional emergency medical response solutions that predict or intervene in life threatening emergencies. To learn more visit www.physio-control.com. 

Phase IIb Study of Vanoxerine Shows Strong Safety and Statistically Significant Efficacy Signals for Treatment of Atrial Fibrillation

ChanRx, a pharmaceutical company developing medicines for cardiovascular diseases, announced positive safety and statistically significant efficacy data from a Phase IIb study of vanoxerine (GBR-12909), a drug in development for the treatment of atrial fibrillation. The data were presented at the American Heart Association 2013 Scientific Sessions.

“Atrial fibrillation affects millions of patients in the U.S. annually, causing substantial morbidity,” said Peter Kowey, MD, Professor of Medicine & Pharmacology, Jefferson School of Medicine and Lankenau Institute for Medical Research. “Currently, drugs that correct this arrhythmia are inadequate and carry safety risks including life threatening arrhythmias, long-term toxicity and liver failure. Both the patients with this condition and the physicians treating them could benefit greatly from a drug that could safely treat this arrhythmia.”

In the randomized, placebo-controlled trial, 104 patients presenting with symptomatic atrial fibrillation or atrial flutter of recent onset were assigned to one of three doses of vanoxerine or placebo. Vanoxerine was found to be well tolerated at all doses. Importantly, no episodes of monomorphic or polymorphic ventricular tachycardia were seen. Ventricular tachycardia is a potentially life-threatening arrhythmia that can lead to sudden death. The majority of currently marketed drugs used for atrial fibrillation have a risk of polymorphic ventricular tachycardia.

“Historically, drugs to treat atrial fibrillation have failed, not because they are ineffective, but because they have significant safety issues,” noted Arthur “Buzz” Brown, MD, PhD, founder and CEO of ChanTest and founder and CSO of ChanRx. “Thus far, the clinical data showing a lack of pro-arrhythmic effects for vanoxerine are extremely promising and mirror what we saw in preclinical studies. If this clean safety record continues in the presence of this high degree of efficacy, vanoxerine could make a real difference in the care of the millions of people afflicted by AF.”

Patients participating in the trial were measured for conversion from atrial fibrillation or flutter to normal sinus rhythm. Overall, there was a highly statistically significant dose-dependent increase in the conversion to normal sinus rhythm (P-value for all doses = 0.0005) compared to placebo. The highest oral dose (400 mg) achieved a conversion rate of 76 percent at 8 hours and 84 percent within the first 24 hours, a rate approaching that of direct current (DC) cardioversion. Patients taking placebo achieved a 25 percent conversion rate at 8 hours and a 38 percent conversion rate at 24 hours.

“Not only has vanoxerine demonstrated very promising safety data, it has statistically significant efficacy signals overall and in the two highest doses tested,” said Howard Dittrich, Chief Medical Officer for ChanRx. “The efficacy data, coupled with a remarkable safety profile in this phase II study, bodes well for the next phase of vanoxerine’s clinical development.”

About Atrial Fibrillation

According to the National Institutes of Health, atrial fibrillation (AF) is the most common type of heart arrhythmia. AF can increase the risk of stroke and can also cause chest pain or heart failure. Treatments for atrial fibrillation include drugs to prevent blood clot formation and drugs that slow down heart rate. Options to control the rhythm of the heart are limited, with DC cardioversion, a non-pharmacological option, being the most common. DC cardioversion is highly effective, but it is a costly, resource-intensive procedure that requires anesthesia and follow up observation. Drug options to control the rhythm of the heart are limited primarily due to toxicity or because they cannot be used widely.

About ChanRx 

ChanRx is focused on developing small molecules for cardiovascular diseases. The company was spun out from ChanTest, the world’s most trusted ion channel services company with particular expertise in testing pharmaceutical compounds for cardiac safety. Its lead candidate is vanoxerine, a small molecule under development for atrial fibrillation or atrial flutter, which has demonstrated promising data in trials through Phase IIb. ChanRx’s Series A funding was provided by Sante Ventures.