Increased repolarization dispersion seen in SCD survivors

November 21, 2017

(HealthDay)—Survivors of sudden cardiac death (SCD) with structurally normal hearts have increased dispersion of repolarization after exertion, and this is detectable on non-invasive electrocardiographic imaging (ECGi), according to a study published online Nov. 1 in the Journal of Cardiovascular Electrophysiology.

Kevin M.W. Leong, M.B.B.S., from Imperial College London, and colleagues applied non-invasive ECGi to 11 survivors of SCD, 10 low-risk Brugada syndrome (BrS) patients, and 10 controls undergoing exercise treadmill testing. Global dispersion of activation recovery interval (ARI) and regional delay in conduction were determined from ECGi and were used as surrogates for spatial heterogeneities in repolarization and depolarization.

The researchers found that after exertion, the largest increase in global dispersion of ARl was seen for the SCD group versus the BrS and control groups (13±8 versus 4±7 and 4±5 ms); baseline dispersion was similar in all groups. Surface ECG markers of dispersion of repolarization were not able to differentiate between the groups at baseline or after exertion. After exercise, there were spatial heterogeneities in conduction; these did not differ significantly between the SCD survivors and the other groups.

"Increased of repolarization is apparent during physiological stress in SCD survivors and is detectable with ECGi but not with standard ECG parameters," the authors write. "The electrophysiological substrate revealed by ECGi could be the basis of alternative risk-stratification techniques."

One author disclosed ties to Medtronic.

Explore further: Nocturnal respiratory rate predicts cardiac risk after MI

More information: Abstract
Full Text (subscription or payment may be required)

Related Stories

Nocturnal respiratory rate predicts cardiac risk after MI

March 10, 2014
(HealthDay)—Among survivors of acute myocardial infarction (MI), nocturnal respiratory rate (NRR) is significantly associated with cardiac mortality, particularly non-sudden cardiac death, according to research published ...

Fragmented QRS predicts cardiac death during exercise

September 27, 2017
(HealthDay)—Fragmented QRS complex may predict risk of exercise-related sudden cardiac death, according to a study published online Sept. 20 in the Journal of Cardiovascular Electrophysiology.

Early invasive doesn't beat selective strategy in NSTE-ACS

April 17, 2017
(HealthDay)—An early invasive strategy has no benefit for reducing the 10-year composite outcomes of death or spontaneous myocardial infarction (MI) for patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) ...

Survivors of childhood leukemia with Down syndrome have unique health risks, benefits

November 6, 2017
Doctors have long recognized that children with Down syndrome are significantly more susceptible to leukemia, and have believed that they also were at higher risk of treatment-related chronic conditions. Now, new research ...

Rhythm is it: Ion channels ensure the heart keeps time

September 9, 2011
The heartbeat is the result of rhythmic contractions of the heart muscle, which are in turn regulated by electrical signals called action potentials. Action potentials result from the controlled flow of ions into heart muscle ...

Dangerous arrhythmia analyzed in a heartbeat

August 31, 2011
Just one second, one heartbeat. That's what is needed for a new, noninvasive functional imaging technology to record data for locating the source in the heart of a dangerous cardiac arrhythmia called ventricular tachycardia ...

Recommended for you

New link found between alcohol, genes and heart failure

May 25, 2018
The researchers investigated faulty versions of a gene called titin which are carried by one in 100 people or 600,000 people in the UK.

Study examines the rise of plaque in arteries

May 25, 2018
The accumulation of cholesterol plaques in artery walls can lead to atherosclerosis, or the hardening of arteries that contributes to heart attacks and strokes. In a new study, Yale researchers investigate how plaque cells ...

Low-dose aspirin could help pregnant women with high blood pressure avoid a dangerous condition

May 25, 2018
A daily dose of aspirin could help pregnant women in the first stage of high blood pressure avoid a condition that puts both mother and baby in danger, according to a new study.

Study shows in-home therapy effective for stroke rehabilitation

May 24, 2018
In-home rehabilitation, using a telehealth system and supervised by licensed occupational/physical therapists, is an effective means of improving arm motor status in stroke survivors, according to findings presented by University ...

Surgery involving ultrasound energy found to treat high blood pressure

May 23, 2018
An operation that targets the nerves connected to the kidney has been found to significantly reduce blood pressure in patients with hypertension, according to the results of a clinical trial led in the UK by Queen Mary University ...

New guidelines mean 1 in 3 adults may need blood pressure meds

May 23, 2018
(HealthDay)—One out of every three U.S. adults has high blood pressure that should be treated with medication, under guidelines recently adopted by the two leading heart health associations.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.