Could your child have a heart arrhythmia?

This article was originally titled "In a Heartbeat" in the September 2009 issue of Canadian Living magazine. Subscribe to Canadian Living today and never miss an issue!

On a warm April night in 2008,16-year-old Taylor Allan was hanging out at a house party not far from her home in Kingston, Ont. The kids were in the backyard, hot-tubbing and jumping on the trampoline. Shortly before 11 p.m., Taylor, a Grade 11 student and star athlete, went to join her friends in the tub. She had less than an hour to live.

As she was about to climb in, Taylor complained of feeling dizzy to her friends. The next minute, she collapsed, never regaining consciousness. She was pronounced dead at a local hospital. "Her friends did everything they could for her with CPR, and paramedics worked on her, too," says Ken Allan, her grieving father. Taylor's heart had gone into a spasm and stopped beating – the result of an undetected genetic defect known as arrhythmogenic right ventricular cardiomyopathy (ARVC), which was later diagnosed on autopsy at the Hospital for Sick Children in Toronto.

ARVC is one of a cluster of inherited conditions that cause the heart to beat dangerously faster or slower than normal, or to fl utter helplessly in an uncontrolled manner known as fibrillation – sometimes leading to sudden death. Each year in Canada 35,000 to 40,000 people die of sudden cardiac death, and an undetermined percentage of them are due to inherited arrhythmias. This is especially true in younger individuals.

Ken believes his daughter may be alive today if there was wider recognition of the warning signs of such conditions, in both the general population and the medical community. Dr. Joel Kirsh, a pediatric cardiologist at the Hospital for Sick Children, agrees. "It's time for these treatable conditions to be at the front of physicians' minds, not at the back of a textbook," he says.

Taylor had been suffering episodes of faintness for some time. Rushed to the hospital after suddenly blacking out during a soccer match in April 2007, she had been discharged with a clean bill of health after routine tests, including an electrocardiogram (ECG) that showed no abnormalities. Ken says they were told that frequent fainting was a normal part of growing up for girls and not to worry since Taylor's tests had come back fine.

New awareness
Until relatively recently, little was known about the prevalence and genetics of these difficult-to-diagnose arrhythmias. Conventional autopsies can miss them as an underlying cause of death, which might be registered simply as a sudden death, cardiac arrest or drowning. To boost awareness of these defects, Taylor's mother, Jackie Allan, has joined forces with concerned physicians and the Canadian SADS Foundation, a charity dedicated to supporting families affected by inherited cardiac rhythm abnormalities, as well as raising public awareness about these potentially life-threatening conditions.

Detected early enough, the silent killers can be managed with drugs such as beta-blockers, which prevent vulnerable hearts from going into a spasm as an overreaction to sudden stress, or with implanted cardioverter defibrillators. These devices can shock an irregular heartbeat back into a normal rhythm. For some patients, a transplant may eventually be necessary.

Page 1 of 4 -- Learn about another form of ARVC - Long Q-T syndrome - on page 2.