Pacemaker prevents fainting among select patient population
A select number of patients who suffer from neurally mediated synope (NMS) a disorder in which the brain fails to regulate heart rate and blood pressure may be good candidates to receive a dual-chamber pacemaker to prevent common NMS-related fainting spells, according to research presented today at the American College of Cardiology's 61st Annual Scientific Session. The Scientific Session, the premier cardiovascular medical meeting, brings cardiovascular professionals together to further advances in the field.
NMS is often benign; however, some patients have few, if any, warning signs or symptoms before an impending attack, which can result in repeated falls and make tasks like driving or operating machinery dangerous.
The use of cardiac pacing to prevent fainting has been controversial: two earlier studies have shown that pacemakers do not benefit patients who suffer from NMS because of severe hypotensive reflex, or a dramatic drop in blood pressure upon standing or tilting. Unlike these, the present Third International Study on Syncope of Uncertain Etiology (ISSUE-3) trial looked at the use of pacemakers among older patients who had severe asystolic NMS, which is not affected by fluctuations in blood pressure. Among these patients, a pacemaker reduced the relative risk of suffering another fainting episode by 57 percent.
"We found that approximately one out of three pacemaker patients will benefit from pacing therapy within the subsequent two years," said Michele Brignole, MD, head of cardiology at the Arrhythmologic Centre, Ospedali Tigullio in Lavagna, Genoa and the study's lead investigator. "Cardiac pacing therapy is effective in reducing syncopal recurrences in this highly selected population."
The study took place in 51 centers, and involved 511 patients over age 40 who had suffered more than three NMS episodes in the previous two years. Doctors used an implantable loop recorder (ILR), a device that acts like a mini-EKG, to record and determine the cause of fainting. Of the 511 patients, 77 of them had a spontaneous asystolic syncope and were implanted with a pacemaker that was randomly selected to the "on" or "off" position. The study's endpoint was fainting reoccurrence.
Fifty-seven percent of the patients who had pacemakers set to the "off" position had a fainting reoccurrence within two years, but only 25 percent of patients with an activated pacemaker suffered a syncope.
As researchers continue to study asystolic fainting, pacemakers may be useful for patients whose NMS impedes daily life and is very unpredictable.
"We estimate that approximately 40 percent of ISSUE-3-like patients receiving an ILR will eventually be candidates for pacemaker therapy within four years," Dr. Brignole said. Dr. Brignole said that younger patients with NMS often suffer a more benign form of the disorder and respond to less drastic treatments, like physical counter-pressure maneuvers.
"The fact that pacing is effective does not mean that it is also always necessary," Dr. Brignole added.
"Cardiac pacing should be a last choice in highly selected patients affected by severe NMS."
Dr. Brignole said a better measurement of a pacemaker's effectiveness would be a study that uses the long-term syncope burden, not the first syncope occurrence, as a study endpoint.
Provided by American College of Cardiology
- iPods may cause pacemaker glitch May 12, 2007 | not rated yet | 0
- Danish trial demonstrates benefits of dual-chamber pacing in treating sick sinus syndrome Aug 31, 2010 | not rated yet | 0
- Pacemaker implantation for heart failure does not benefit nearly half of the patients Jun 13, 2011 | not rated yet | 0
- Study shows fainting factor in cardiac arrests Feb 09, 2012 | not rated yet | 0
- Researchers find cardiac pacing helps epilepsy patients with ictal asystole Mar 23, 2011 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
The Durability of Bone: Long Falls
5 hours ago I am doing a paper on the physics in Valve's Portal and got interested in the "Long Fall Boots" that prevent any damage no matter how far you fall. I...
Is energy convertible to matter?
7 hours ago Can we convert energy to matter?
Rotating electron as a dipole is this right?
9 hours ago An electron as shown by the Stern Gerlach experiment behaves like a dipole (albeit only in one of two states). I have been trying to figure out how...
Dipole term in multipole expansion
13 hours ago Hi. I'm having some difficult in understanding something about the dipole term in a multipole expansion. Griffiths writes the expansion as a sum of...
Bubbles in a Pre-Boiling/Boiling pot of water
14 hours ago How is it that bubbles form on the bottom of a surface of a pot of boiling water? I think that there is probably an elementary answer to this...
Assumptions of Griffith's fracture theory
May 21, 2013 Any experts on Griffith's fracture theory? I am studying the subject and I am having hard time finding out if the theory is valid for all possible...
- More from Physics Forums - Classical Physics
More news stories
The Orsiro stent, which is a novel stent platform eluting sirolimus from a biodegradable polymer, demonstrated non-inferiority to the Xience Prime everolimus-eluting stent for the primary angiographic endpoint of in-stent ...
Cardiology 10 hours ago | 5 / 5 (1) | 0
One-year results from SOURCE XT – one of the largest, post-approval transcatheter aortic valve implantation (TAVI) registries to-date – reported today at EuroPCR 2013 show good clinical outcomes in routine clinical practice, ...
Cardiology 10 hours ago | not rated yet | 0
A drug commonly used to treat depression and anxiety may improve a stress-related heart condition in people with stable coronary heart disease, according to researchers at Duke Medicine.
Cardiology 11 hours ago | 5 / 5 (1) | 0 |
(Medical Xpress)—In a recent subgroup analysis of the largest blood pressure treatment trial in history, University of Alabama at Birmingham (UAB) researchers found that women and men react the same to ...
Cardiology 19 hours ago | 5 / 5 (1) | 0
(Medical Xpress)—Native peoples in regions where cameras are uncommon sometimes react with caution when their picture is taken. The fear that something must have been stolen from them to create the photo ...
16 hours ago | 4.2 / 5 (5) | 0 |
(Medical Xpress)—Despite spending billions of dollars on research and development, drug companies have been unable to come up with effective treatments for dementia and Alzheimer's Disease (AD). Now, A. ...
14 hours ago | 4.9 / 5 (12) | 0 |
Australian scientists have charted the path of insulin action in cells in precise detail like never before. This provides a comprehensive blueprint for understanding what goes wrong in diabetes.
16 hours ago | 4.6 / 5 (7) | 0 |
An experimental sleeping pill from US drug company Merck is effective at helping people fall and stay asleep, according to reviewers at the US Food and Drug Administration, which could soon approve the new drug.
10 hours ago | 4 / 5 (4) | 0
Activating an enzyme known to play a role in the anti-aging benefits of calorie restriction delays the loss of brain cells and preserves cognitive function in mice, according to a study published in the May ...
10 hours ago | 5 / 5 (4) | 0 |
Researchers at USC have found that a class of pharmaceuticals can both prevent and treat Alzheimer's Disease in mice.
13 hours ago | 5 / 5 (6) | 0 |