Irregular heartbeats can raise a person's risk of death even when they go unnoticed by traditional heart monitoring, according to a Northwestern Medicine study in . Atrial fibrillation—rapid, irregular beating of the heart—is the most common type of irregular heart rhythm, affecting more than 2 million people in the U.S.
, according to the Centers for Disease Control and Prevention. While can have deadly consequences, most don't even know they have the condition, said Rod Passman, MD, the Jules J. Reingold Professor of Electrophysiology and senior author of the study.
"Almost everything we know about atrial fibrillation is gleaned from clinical atrial fibrillation, meaning that you walked into your doctor's office with so much atrial fibrillation that your doctor was able to pick it up on a or an electrocardiogram," said Passman, who also directs the Center for Arrhythmia Research. "Our study, however, looked at what's called subclinical atrial fibrillation. Patients who have implantable pacemakers and defibrillators may have episodes of AFib picked up by their device that they're completely unaware of.
The question we wanted to ask is, is 'Does subclinical atrial fibrillation have equal impact on mortality as clinical atrial fibrillation?'" In the study, Passman and his collaborators analyzed data from more than 20,000 people with pacemakers or defibrillators. Investigators then compared episodes of atrial fibrillation with instances of death after two years and found tha.