Covid-19 and Long QT Syndrome - risks of returning to work

[Andyroo66]

Hi

ive not worked for a while and have the offer of a job at short notice but it would be working on a manufacturing site and not from home.

As I also have some anxiety I am getting terrified of the risk of catching Covid-19 , especially as I have Long QT Syndrome which means some of the anti- malaria drugs and antibiotics cannot be used in treatment.

I am trying to weigh up the risk to see if it's worth it or I should stay at home and stick it out. I've just started feeling better after a long illness I'm not sure I want to run the risk (53 year old male )

[Shcldavies]

The only meaningful advice you could possibly get is to speak to your Cardiologist, only they know enough about your condition and have the ability to provide you with an informed risk assessment.

[Palpman]

Do you have a genetically increased LQTS or is it drug induced and how long is it?

[Andyroo66 in reply to Palpman]

thanks both, I'm gonna ask my cardio some more questions, im not sure it's either genetic or drug induced, I had a blood test for the gene marker and they couldnt find anything other than small piece of variation in KCNQ1. I don't have blackouts but my QT is typically raised 480ms or so and has been higher 500ms or so on amitriptyline which I had to stop.

[Palpman in reply to Andyroo66]

Your QT of 480 is about what I also had when I was on 2 QT prolonging drugs, Flecainide and Sertraline.

All mood changing drugs and antidepressants prolong the QT duration.

It is important to have the cQT duration rather than plain QT as it does not include the heart rate.

LQTS of 600 to 800ms is typically found in suicide patients that have overdosed on Flecainide or similar drugs.

To get to dangerous levels where TdP can occur, one has to seriously overdose or have the bad gene together with high blood plasma levels of certain drugs.

I suggest you mention this to your GP as they have recently been made aware of the dangers of LQT and Covid-19.

[Andyroo66 in reply to Palpman]

Thanks, it's actually the QTc of 480 or so not QT. My GP and Cardio has advised I should be ok, well as OK as you can be in a pandemic!

[Crash88 in reply to Palpman]

sorry to stick my nose in ur convo but can TdP happen randomly? or do u specifically need to be overdosing on something or just have very bad tachycardia?? i was always curious on how TdP shows up and if it can happen to someone healthy just suffering from occasional ectopic beats!

[Palpman in reply to Crash88]

Only 1 in 7,000 people will get an episode of torsades as it is not a common arrhythmia.

An ECG trace will not state that you have LQTS but it will state your cQT duration.

To determine if you could be susceptible for torsades you must refer to the Schwartz TdP table. It's a points system that is something as follows.

cQT of 480ms or more is 3 points.

Bradicardia 0,5 points.

cQT of 440 to 460ms 2 points.

Family member with LQTS 0.25 points.

Notched T wave 0.25 points.

A total of 3 or more points will be a determinant for LQTS. All "anti" drugs like antidepressants, antibiotics and antiarrhythmic drugs that cause long QT must be stopped to determine if one is prone to LQTS.

Low potassium levels or hypokalemia can also increase the QT period or widen the QRS wave.

Low levels of calcium and magnesium can also do so but to a lower degree.

I suggest you look at every ECG you get to see how long the cQT duration is. Must be lower than 440ms.

It is difficult to get an ECG trace of a person with TdP as it mostly

spontaneously reverts by itself or with syncope.

If it sustains, the patient must be reverted medically or with a defibrillator as death may occur.

TdP is mostly only observed in lab rats and people attempting suicide with medication. QTc of 800ms have been observed in these patients.