Heart Education Awareness Resource and Training through eLearning (HEARTe)

Symptoms & triggers

It is important to note that an individual with inherited LQTS may be asymptomatic until a QT interval prolonging drug is taken. Margaret had no cardiac symptoms until she commenced trimethoprin. Following her aborted sudden cardiac death episode, she was admitted to the Coronary Care Unit for observation and further investigation.

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Pulse point

The fact that Margaret has a family history of Sudden Cardiac Death should be a red flag trigger to consider inherited LQTS.

 

Symptoms Triggers
  • Syncope (often misdiagnosed as common faint or seizure)
  • Palpitations
  • Sudden death
  • Sudden loss of consciousness during physical exertion or during emotional excitement should strongly raise the possibility of LQTS
  • Family history of unexplained syncope or sudden death in young people should also raise suspicion of LQTS
  • QT interval prolonging medications
  • Swimming, running
  • Startle: alarm clock, loud horn, ringing phone
  • Emotions: anger, crying, test taking or other stressful situations
  • Sudden death may also occur during sleep
  • Electrolyte imbalance

Dialogue between Margaret and cardiac consultant

Scene 1:

Consultant: Hello. I’m Dr Buchan, one of the cardiac consultants here in the Coronary Care Unit. How are you feeling today?

Margaret: Not too bad, thank you. I feel a bit battered and bruised but the nurses tell me that’s from when people were trying to get my heart going again.

Scene 2:

Consultant: Can you tell me what happened yesterday?

Margaret: I don’t remember much, to be honest. My daughter and I had just come back from a shopping trip. I remember feeling very dizzy and woozy, and having palpitations. I was thinking that I was going to faint and would need to sit down…after that, the next thing I remember is waking up in hospital.

Scene 3:

Consultant: Have you ever had any turns like this before? Have you had problems with your heart in the past?

Margaret: No, never. It was very scary. I’ve never had heart problems – plenty of problems with other parts of my body but not my heart!

Scene 4:

Consultant: I’m sure it must have been very frightening for you. Are you on any medications at all?

Margaret: I’m on medications for my diabetes, but that’s all. Oh, and I’ve had a urinary tract infection so I’ve just started a tablet for that.

Scene 5:

Consultant: I wonder if that may be part of the problem. Have you got the tablets with you?

Margaret: No, but I can get my daughter to bring them in.

Scene 6:

Consultant: That would be helpful. One last question, for now. Has anybody in your family ever died suddenly or unexpectedly?

Margaret: Well, let me think. My mother died when I was very young – just “dropped” according to my father but I was too young to remember much about it. One of my cousins on my mother’s side also died when she was just a schoolgirl.

Scene 7:

Consultant: Thank you, Margaret. We’ll be keeping you in and doing a few more tests on you today, so I will come back and see you later.

Margaret: Thank you, doctor.

Pulse point

Certain forms of competitive exercise are known triggers for dangerous arrhythmias in individuals with LQTS. For information, please see: