SEP 05, 2016

Connecting the Brain and Heart in Long QT Syndrome

WRITTEN BY: Brenda Kelley Kim
A rare but often fatal heart condition known as Long QT Syndrome (LQTS) is getting some new attention from a study done at the University of Rochester Medical Center. LQTS can be a congenital condition and estimates are that it occurs in about 1 in 2500 live births. It can also be developed as a result of using certain medications. It causes an irregular heartbeat, but in some cases can bring on sudden cardiac death. Researchers at the University of Rochester Medical Center recently found a genetic link between LQTS and an increased risk for seizures.  Furthermore, those who have it and suffer from seizures are then at an even higher risk for sudden cardiac death.
 
According to research published this week in the journal Neurology, a definite association exists between the heart and the brain in LQTS patients. When a person carries the genetic mutation that causes the syndrome they were three times more likely than their family members without the mutation to suffer seizures. The patients who had seizures also tended to have more severe cardiac symptoms than those who didn’t. The data from the study shows clearly that the two most important organs in the body, the heart and the brain, are most definitely connected in some way that is relevant to LQTS.
 
The study, conducted at the Aab Cardiovascular Research Institute of the University of Rochester Medical Center by David Auerbach, Ph.D., showed that the biomarker of seizures was the strongest factor in predicting cardiac arrhythmias that are the hallmark of LQTS. In fact, about 20% of the LQTS patients in the study who had a history of seizures had survived at least one serious cardiac arrhythmia. 
 
This study is the first to explain the link between seizures and LQTS. Increasingly health professionals are being called upon to look at more than just one part of a disease or disorder. With LQTS, what might seem to be just a cardiac problem is actually neurological as well. Auerbach is familiar with the heart-brain connection having studied a genetic form of epilepsy as a post-doctoral researcher. In that work he found that irregular heart rhythms were a cause of unexplained sudden death is epileptics. In his recent work, he wanted to look at the reverse situation, to see if a cardiac condition could be connected to a neurological outcome.
 
The study was funded by the University of Rochester Clinical and Translational Science Institute and used data from the Rochester LQTS patient registry.  Of interest is the fact that this resource was created 40 years ago by Arthur Moss, M.D., who is the Bradford C. Berk, MD, PhD, Distinguished Professor of Medicine at URMC. It contains detailed information from more than18,000 people including LQTS patients and their affected and unaffected family members. This data provided the perfect control group—subjects with the same genetic material except for the mutation.
 
There are three different sub-types of LQTS and while the arrhythmias in each are somewhat similar, the seizures in patients with different types are not the same. Auerbach found that patients with LQTS2 were at the highest risk for seizures and as a result sudden cardiac death. The team at Rochester hopes to do more work on the link. In a press release Auerbach stated, “you could begin applying these findings to patients today by telling physicians treating LQTS patients to look outside the heart.” The video below talks about more details of the study.

Sources: NIH, University of Rochester