A new therapy to re-engage the heart’s natural electrical pathways – instead of bypassing them – could mean more treatment options for heart failure patients who also suffer from electrical disturbances, such as arrhythmias, according to research led by the University of Chicago Medicine.
In a first-ever pilot study, called the His SYNC trial, researchers compared the effectiveness of two different cardiac resynchronization therapies, or treatments to correct irregularities in the heartbeat through implanted pacemakers and defibrillators. The current standard of care, known as biventricular pacing, uses two pacing impulses in both lower chambers, whereas the newer approach, called His bundle pacing, attempts to work toward engaging and restoring the heart’s natural physiology. The two approaches have never before been directly compared in a head-to-head clinical trial.
“This is the first prospective study in our field to compare outcomes between different ways to achieve cardiac resynchronization,” said cardiologist Roderick Tung, MD, FHRS, the Director of Cardiac Electrophysiology & EP Laboratories at the University of Chicago Medicine. “Through His bundle pacing, we’re trying to tap into the normal wiring of the heart and restore conduction the way nature intended. Previously, we have just accepted that we had to bypass it through pacing two ventricles at a time.”
Tung spearheaded the two-year trial with UChicago Medicine cardiologist Gaurav Upadhyay, MD, FHRS, lead author of the study. The trial involved 40 adult patients across seven institutions in the Midwest. The UChicago Medicine team served as the independent coordinating site. Results of the study were presented as a featured late-breaking trial at the Heart Rhythm Society’s annual scientific sessions in San Francisco on May 9. To qualify as a late-breaking trial, the research must be groundbreaking and unique. The study was also published in the Journal of the American College of Cardiology.
A different resynchronization method
Biventricular pacing involves implanting wires, called leads, to simultaneously pace the right and left ventricles of the heart. A pacemaker then sends a timed electric pulse to the two leads with the goal of a synchronized contraction, which closely simulates the heart’s natural heartbeat.
Nevertheless, roughly 30 percent of patients do not respond to biventricular pacing treatment, which has been shown to improve survival in clinical trials.
Tung’s team looked to see if another resynchronization method could help reduce that number by doing a clinical trial comparison between biventricular pacing and His bundle pacing. The latter involves implanting a single lead at the start of the heart’s wiring system, which then naturally branches in two to organically distribute the pacemaker’s electric pulse to both ventricles.
“Permanent His bundle pacing has been around for almost 20 years, but until now there hasn’t been randomized clinical trials on how it compares to biventricular pacing,” Tung said.
For the His SYNC trial, all of the patients met the current guidelines for receiving cardiac resynchronization therapy and were randomly selected to receive either a His bundle pacer or a coronary sinus lead for biventricular pacing. Patients weren’t told which treatment they received.
While the results of the preliminary study did not demonstrate superiority with His-CRT, Tung and his team believe a His bundle pacing approach showed comparable rates of response, warranting further study. The research was limited by a high crossover rate, which was required by the study’s protocol if an adequate lead placement could not be achieved. Nearly half of the patients selected to receive His bundle pacing had to eventually be treated with traditional biventricular pacing due to having a condition called interventricular conduction delay (IVCD). The implantation tools have also not been refined since their introduction 10 years ago.
“We need to learn how to better identify patients who cannot and will not respond to His bundle pacing,” Tung said. “During this pilot study, we learned that the net was cast too wide, and patients with IVCD can’t be corrected and improved by His bundle pacing. His SYNC II, our planned follow-up study, will specifically exclude these patients and this is perhaps the most valuable lesson from the pilot, in addition to estimated treatment effect size.”
In addition, 26 percent of patients chosen to receive biventricular pacing did not, usually because a lead could not be inserted due to the condition of their veins dictated by strict criteria to optimize implantation of left ventricular leads.
Comparing the two approaches
After six months, researchers compared the electrical synchronization and structural function of the two patient groups’ hearts. Although they expected His bundle pacing to be superior, they found no overall significant differences in the two groups, with comparable rates of electrical resynchronization and echocardiographic response.
After one year, there were no differences in the number of hospitalizations or deaths.
Noting the pilot study was limited by its size, Tung says the results indicate further investigation is needed.
“Pilot studies are never meant to be conclusive,” he said. “They’re meant to inform us about effect size, safety and feasibility to help select appropriate patients and power larger studies.”
Learn more: Treatment option to restore natural heartbeat could be on the horizon for heart failure patients
The Latest on: Heart failure
[google_news title=”” keyword=”heart failure” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Heart failure
- Why Are Younger Adults Developing This Common Heart Condition?on April 23, 2024 at 10:07 am
New research suggests that A-fib may be more prevalent, and more dangerous, in people under 65 than previously thought.
- Exo® Launches FDA-Cleared AI on Exo Iris™ to Address Heart Failureon April 23, 2024 at 5:58 am
Exo ® (pronounced "echo"), a medical imaging software and devices company, today announced its FDA-cleared cardiac and lung artificial intelligence (AI) applications are now available on Exo Iris ™, ...
- Women's heart disease is underdiagnosed, but new machine learning models can help solve this problemon April 22, 2024 at 9:00 pm
When it comes to matters of the heart, cardiovascular disease in women is underdiagnosed compared to men. A popular scoring system used to estimate how likely a person is to develop a cardiovascular ...
- Ahead of Alnylam's key heart disease readout, experts say Pfizer rival would be hard to displaceon April 22, 2024 at 7:55 am
As a closely watched readout from Alnylam Pharmaceuticals' Amvuttra in the rare heart disease transthyretin amyloid cardiomyopathy (ATTR-CM) is expected in a few weeks, experts suggested the RNA si | ...
- Heart Disease: How The DASH Diet Can Help Lower The Risk After Breast Cancer Treatmenton April 19, 2024 at 10:05 pm
Share on PinterestExperts say a healthy diet is important after breast cancer treatment. Johner Images/Getty Images A new study states that a healthy diet can reduce the risk of heart disease in ...
- Medical Compass: What are the best ways to reduce your heart disease risk?on April 19, 2024 at 9:08 am
Heart disease is on the decline in the U.S. Several factors have influenced this, including better awareness, improved medicines, earlier treatment of risk factors and lifestyle modifications (1).
- A-Fib Is Strong Precursor to Heart Failureon April 19, 2024 at 4:27 am
The dangerous heart rhythm disorder known as atrial fibrillation is mainly known for increasing people’s risk of stro ...
- New Heart Failure After AF Diagnosis Merits More Attentionon April 18, 2024 at 1:55 pm
Prevention of stroke gets highlighted by guidelines and is top-of-mind for patients, but heart failure is much more common.
- Study: Heart failure, not stroke, most common complication of atrial fibrillationon April 18, 2024 at 12:19 pm
Doctors tell patients with atrial fibrillation, which causes an irregular and often abnormally rapid heart rate, to beware of an increased risk of stroke. But the threat of heart failure should be ...
- Heart Failure, Not Stroke, Is Most Common Complication of AFib, Study Findson April 17, 2024 at 5:00 pm
A new study found that for those who receive a diagnosis of atrial fibrillation, the most common complication is heart failure, followed by stroke.
via Bing News