What Does Incomplete Penetrance Of Long QTc Mean?

Posted on Wed, 6 Aug 2014

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Wed, 6 Aug 2014 Answered on

Fri, 22 Aug 2014 Last reviewed on

Question : Hi I've just been diagnosed with incomplete penetrance with long QT. I got taken off atacand plus and the QTc went back to 390ms from 590ms. I also had an angiogram which was normal and a echo with was normal. This was 3 months ago. I had another ECG last week and my QTc was normal. I have started getting sharp stabbing pains in my chest which lasted for about 5 minutes ,they came on and off. Could this be heart related considering all the tests I've had. I don't get any pain while exercising. I'm a 44 year old male.
Cheers
XXXXXX

Answered by Dr. Sukhvinder Singh (1 hour later)

Brief Answer:
please see details

Detailed Answer:
Dear sir
Incomplete penetrance of long QTc means your QTc interval may increase abnormally under certain provoking conditions like low potassium, low calcium, very low heart rate, certain drugs, head injury etc. So you must obtain a list of such medicines from your doctor or any related reliable website.
However unprovoked sharp pain is not a character of cardiac pain neither long QT interval is known to be associated with such pains. A normal coronary angiogram is reassuring. It virtually rules out anginal pain.
Sincerely
Sukhvinder

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar