Dec. 16, 2009 -- British teenager Tom Reid visited a nightclub the day after enrolling in college. It seems the loud music he heard there may have killed him.

According to reports in the British press, Reid died at a London nightclub after complaining that the bass was affecting his heart rate. While definite answers have been hard to come by, an underlying condition may have played a role in his death.

While details remain unclear, experts in the United States say that given the circumstances, the death matches the profile of someone with a rare genetic disorder known as long QT syndrome, although they cannot say for sure.

"Any time someone in a setting of excitement has a sudden cardiac arrest, especially at a young age with a seemingly normal heart, you have to consider [an inherited condition] such as long QT," said Dr. Richard Page, chair of medicine at the University of Wisconsin School of Medicine and Public Health and president of the Heart Rhythm Society. "One of the genetic variants is especially predisposed to having an arrhythmia when exposed to loud sound."

While loud sounds have been known to set off irregular heartbeats in patients with long QT syndrome, it is unclear whether the thumping bass, in particular, had any effect.

"I don't think the bass is the problem per se, just the loud noise," said Dr. Anne B. Curtis, chief of cardiovascular disease at the University of South Florida.

Reid's family could not be reached by ABCNews.com for comment.

But while the genetic disorder is rare, many have been affected by long QT syndrome.

"My story is one of thousands," Mary Jo Gordon, executive director of the Cardiac Arrhythmias Research and Education (C.A.R.E.) Foundation, Inc. told ABCNews.com.

Gordon became involved in research and advocacy for heart conditions after her sister suffered cardiac arrest at the age of 17, in 1979. While Gordon's sister survived, she requires round-the-clock care today because of the brain damage that resulted.

A Silent Disease, Triggered by Noise

Gordon has since worked as a medic and in the medical devices industry. But it was years after her sisters attack before she learned she, too, had long QT.

"I didn't find out until 1993," she said, explaining that, as one of eight siblings, they all were tested. "Of the eight of us, five of us have the disorder."

Gordon said another sister had cardiac arrest at the age of 22, while a nephew has had cardiac arrest twice. Typically, she said, it is a result of symptoms or a family member when the disorder will be discovered.

Fortunately, however, testing can be done, in the form of an ECG or EKG, which will detect the vast majority of cases, and through medication, a pacemaker or a defibrillator, "If they find it, it's treatable," said Gordon.

Long QT syndrome derives its name from the fact that on a heart monitor, the phase of the heartbeat between points known as Q and T would be lengthened.

It comes in a few variants, and they can be triggered by a variety of conditions.

In some cases it can be caused by exercise, and in other variants, being in the water seems to cause it.

"My sister's cardiac arrest was caused by a minor car accident," said Gordon, explaining that a sudden startling event can play a role.

In her nephew's case, the cardiac arrest was triggered by an alarm clock, and in one family she spoke with recently, a 6-year-old patient suffered cardiac arrest because of a security alarm.

The 6-year-olds parents, however, saved the child's life by doing CPR -- a successful story that may provide a lesson for anyone worried about losing a loved one to a sudden heart attack.

"I don't think that this is a call for action for not standing near a loud speaker. But I do think that any time a young person dies it is an opportunity to remind all of us that public places should have AEDs, and we all should know CPR," said Page.

In Reid's case, it seems unusual only because the music was continuous, and does not appear to have been the result of a single loud burst of sound.

"The usual description of auditory-triggered arrhythmias and death have been those that occurred suddenly such as an alarm clock or an explosion, not usually a continual loud noise," said Dr. Thomas McDonald, a cardiologist at the Albert Einstein College of Medicine in New York. "Of course, I have no idea of the tempo or volume dynamics of the music in this concert."

Lessons from Tragedy

While diagnosing long QT syndrome can prove difficult after death, it can be important for relatives of someone who dies from sudden heart failure to get a genetic test.

One thing that should be done in the case like Reid's is "they should do post mortem genetic testing to get a definitive cause of death. This would have implications for family members," said Dr. Laurence Epstein, chief of the arrhythmia service and Brigham and Women's Hospital in Boston.

Indeed, diagnosing long QT syndrome after death can prove tricky without genetic testing.

When the coroner does the autopsy, "There's not [an] enlarged heart, there isn't necessarily plaque in their arteries," said Gordon.

In an annual screening event her group does at Madison Square Garden, where they give free ECGs to 200 children, Gordon said they ask about a history of sudden death in families as well as unexplained fainting, convulsions, seizures or dizziness in individuals.

But as shocking as the sudden death of a young person may be, long QT syndrome is not something the average person needs to worry about.

"It is infrequent and there is no reason for public alarm, if indeed this is the cause of death in this individual," said Dr. Douglas P. Zipes, editor-in-chief of HeartRhythm and a cardiologist at the Indiana University School of Medicine.

In the end, Page said, the vast majority of people at a loud nightclub should have bigger concerns than their hearts.

"I feel that people are more at risk for damage to their ears rather than heart arrhythmias from loud music," he said.

Dan Childs contributed to this report.

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For more information:

Cardiac Arrhythmias Research and Education (C.A.R.E.) Foundation, Inc.