What is Long QT Syndrome


As you know Isla has a condition called Long Qt syndrome, I’d like to explain a little more about Long Qt. Part of my website is eventually going to be dedicated to sharing my knowledge and experience of Long Qt Syndrome.

So far this year I have helped 3 people understand and get effective treatment for their or their children’s Long Qt syndrome. One of these people was told by her doctor that she had Long Qt, and as he didn’t really know what that was, he told her to google it. It really is an uncommon condition even for doctors.

One of the main issues with Long Qt Syndrome is that the first symptom of it is death. For that reason I’m actually grateful we found out so early about Isla’s condition. We would have woken up one morning to find she was no longer with us, and it probably would have been chalked up to cot death, sending us down a trail of guilt and ‘what if’. The fact is that 1 in 5000 (some say 2000, some say 7000) have Long Qt Syndrome. Left untreated, more than half of those with the condition would die within 10 years. It’s a scary thought. There are people on Long Qt groups who got to 40 without any symptoms but then had a sudden cardiac arrest. They haven’t just developed the condition, it’s been there all along. It’s a silent killer. Long qt is a latent condition. The arrhythmia isn’t always there, but the threat of it is.

In a normal heart beat, electrical impulses cause your heart to contract and pump blood around your body. After each beat the heart relaxes and there is a pause before the next beat. The QT interval is the time it takes for the heart to contract, relax and recharge. In Long Qt syndrome, your heart muscle takes longer than normal to recharge between beats so the electrical impulses tell the heart to beat but it’s not finished relaxing yet.


Put in a real life situation…
You’re at Aldi (other supermarkets are available) where you’re trying to keep up with the cashier. More items and more items are coming at you, you’re doing well, you’re keeping up. But then, you spend too long trying to get something in the bag, but the items keep coming and you’re not ready. Sometimes you’re able to rally and sort it out, but it often just ends up in chaos and the packing system goes out the window in a hurry to avoid embarrassment. Everything gets thrown in the trolley to be sorted later. You end up all hot and sweaty, feeling the pressure, I doubt you’d faint, but you could. They read out the final price for your shopping and you’re no where near ready, there’s a massive queue waiting, you feel like you could just die. That’s Long Qt, in a nut shell. Of course some people won’t ever have this sensation. They’re either expert baggers or they go to a supermarket where they ask if you want assistance with your packing. That would be a normal Qt. Item scanned, item bagged; like clockwork! No unexpected items in your bagging area or holes in your bag for life… that you know of anyhow!

There are known to be at least 17 types of Long Qt caused by mutations in different genes. Three of these genes account for 75% of all Long Qt. A longer than normal Qt interval in people may never cause a problem so some people with Long Qt may have a gene mutation but live a full and healthy life unaware of their genetic variation. However, the different Long Qt types have different triggers that may cause the heart to go in to checkout chaos. These triggers could be physical or emotional stress might “trip up” a heart‘s normal rhythm.

I’m going to use a car analogy now for how I understand the different Long Qt triggers. The heart is your engine after all.

Long Qt 1 is usually caused by exercise and a fast heart rate. So imagine you’re in your car at the lights in 1st gear. You set off but get to 30 without changing gear! You went too fast, too soon and the engine is screaming.

Long Qt 2 is typically caused by emotional stress or surprise. People with LQT2 are advised to not have alarm clocks as it could trigger an arrhythmia. For LQT2 I imagine being at traffic lights, fiddling with the radio, not noticing the lights turning green, and the angry car behind beeps loudly. You instinctively put your foot down and jolt forward.

Long Qt 3 is more often a drop in heart rate and so happens at rest or sleep. This is what Isla has and why she has a pacemaker. To me, this is an emergency stop situation where you have to go from 40mph to 5mph but without changing gear. The engine can’t handle that and stalls.

These are obviously very simplistic explanations and wouldn’t always be the case but that’s the best way I can visualise how things can go wrong in an Lqt heart. There doesn’t always have to be a trigger. Without medication, Isla’s Qt interval is just too long so has arrhythmias regardless as it takes so long for her heart to recharge after a beat.

The actual issues which cause Long Qt are down to electrolyte malfunctions. With Long Qt 1 and 2 it’s potassium, with Long Qt 3 it is sodium. I guess therefore you’d have to liken Long Qt with it’s electronic faults to a French car. Their electrics always go wrong. Yes Peugeot, I’m talking about you.


When the normal heart rhythm falters it can spin out of control leading to a fast and uncoordinated beat. The arrhythmia is called a Torsades de Pointes (TdP) – twisting of the points. The lower chambers of the heart beat extremely fast and chaotically. When this happens less blood is pumped around out of the heart and less reaches the brain, resulting in fainting. A TdP may resolve itself and the person regains consciousness but if this arrhythmia last longer than a minute, the lack of blood to the brain may cause a seizure. The arrhythmia may also escalate further and become Ventricular Fibrillation (VF). During VF the heart quivers rather than beats and so ceases to pump blood at all. The only way out of VF is by shocking the heart back into normal rhythm.

Currently there isn’t a cure for Long Qt. It’s a condition that is just managed and sufferers must adapt their lifestyles to minimise risk. Mostly that includes beta blockers which stop the heart rate going too fast. Some have pacemakers to keep the heart rate from dropping suddenly or an icd to provide corrective or rescue shocks, bringing the heart back into rhythm.

The best thing anyone reading this can do is learn CPR and the actions to take as a first responder. You might just save someone’s life! They might be a Long Qt sufferer!

I hope that goes some way to explaining what Long Qt is and why it is so sucky!