What is Long QT Syndrome and how might it affect you?

Monday, 30 April 2012 08:56

Last night's episode of Silent Witness on BBC1 revolved around a sudden death, suspected to be caused by the heart condition Long QT Syndrome. But what is the condition, what does it do and how can it be treated?

As with the majority of Silent Witness episodes, the drama began with an unexplained death as a seemingly healthy teenage girl, Eve, was found dead in her room. Pathologist Leo Dalton initially suspects that sudden arrhythmic death syndrome must be the cause as many heart conditions are very hard to detect and can affect people of all ages and fitness levels.

Dalton also suspects that Long QT Syndrome is the cause of Eve's cardiac arrest. Long QT is a heart condition where there is a prolonged amount of time between the start of the 'Q wave' (the tall, narrow wave) and the end of the 'T wave' (the shorter, wider wave) of the heart's rhythm as it appears on an electrocardiogram (ECG). This can create an irregular heartbeat which may lead to ventricular fibrillation causing palpitations, fainting or sudden death.

Extraordinarily, Long QT was first documented over 60 years before an ECG was fully invented. In 1856, a girl collapsed and died after a school teacher yelled at her and it was noted that her brother, who was also deaf, suddenly died after suffering a fright. This is thought to be the first described case of Jervell and Lange-Nielsen syndrome, one of 13 types of Long QT, which is also associated with congenital deafness. Intriguingly, Eve's younger brother is noted to be blind with an acute sense of hearing, although it is later revealed that he has not been blind from birth. Of the 13 types of Long QT, LQT1 is the most common, making up 30-35 percent of cases. All variants of the condition are caused by the genetic mutation of several genes but it has also been recorded that anti-arrhythmic drugs can induce Long QT.

Although the plot later seems to move away from the diagnosis of Long QT, it suits the themes of mystery and uncertainty often involved in Silent Witness as it can be very hard to diagnose and Dalton mentions that it is almost impossible to recognise after a patient has died because there is no longer any electrical signal in the heart to measure. Dalton plans to test the rest of the family for Long QT, as it is a genetic disorder, and investigate the family history but meets opposition from the family who are very resistant and unwilling to talk with him.

Two different forms of treatment are available for Long QT; arrhythmia prevention and arrhythmia termination. Arrhythmia prevention involves the use of medication or surgery to reduce the potential for heart arrhythmia to occur. The first treatment will often be the administration of beta blockers whilst potassium and mexiletene are both involved in experiments to develop further treatments. Arrhythmia termination is the treatment of a patient who has already gone in to arrhythmia to restore a normal heartbeat. One a patient has gone into ventricular fibrillation, the only effective treatment is a defibrillating shock administered either internally, with an implantable cardioverter-defibrillator (ICD), or externally with an automated external defibrillator (AED).

So, what can you do to protect yourself from Long QT? If you have any family history of sudden arrhythmic death or Long QT Syndrome then you should certainly see your doctor, have an ECG screening and ask for advice on any treatments you may need. Unfortunately, heart screening is not always guaranteed to discover a problem and it is important to be prepared in other ways in case you, a member of your family or someone you work with suffers from a heart condition which could cause a cardiac arrest.

Long QT also affects young people and is one of the heart conditions which can cause 270 children to die at school each year after suffering a sudden cardiac arrest.

You can help Hand on Heart protect more children from sudden cardiac arrest with the following steps:

Nominate a school for a Hand on Heart grant! - Hand on Heart provides grants to nominated schools so that they can purchase a defibrillator package, including a defibrillator and CPR training for 8 staff and 30 pupils. Nominate a school and you could be helping to make a heartsafe school!

Help fundraise for a school defibrillator package - As our funding doesn't cover the whole cost, schools also need to raise funds to purchase the defibrillator package. You could help a local school get its package by doing a sponsored run, quiz night, or football match, or anything you like!

Donate to Hand on Heart! - Of course, to keep running Hand on Heart also relies on the generosity and good will of the public who support us through the year with donations. You can visit our Donations page or text "HAND88 £3" to 70070 to make a quick and secure donation to our charity!