What could be the reason for increased heart rate of my pregnant wife?

Question

Hi doctor,

My wife is 34 weeks pregnant. She has known tachycardia and had an unsuccessful ablation at 11 years old. Around six weeks ago, using a pulse oximeter I have at home, I noticed her resting heart rate had dramatically increased. It went from an average of around 100 to around 130 and 140, sometimes 123. She has just had a 48-hour tape fitted today, and amazingly her heart rate has now dropped to an average of 95. She has not been stressed about her heart, so it cannot be the reason why all of a sudden it has dropped. What could be the cause of this?

Please help.

Answer 1

Hi,

Welcome to icliniq.com.

Tachycardia, that she had, was mostly probably PSVT (paroxysmal supraventricular tachycardia) or other SVT (supraventricular tachycardia), which are usually episodic. So, the reading you had of 123 was probably not due to her old heart problem PSVT, but it was sinus tachycardia may be because of activities or stress, dehydration, pain, etc, and baseline heart rate at the time was also probably in the same range. Heart rate is a highly variable parameter.

Heart rate normally changes with many things like anxiety, activities, fever, dehydration, and many others and this is very well normal. A heart rate of 120 to 140 could normally be achieved. If one has an episode of PSVT, then he would be symptomatic like severe palpitations, shortness of breath, chest pain, and a heart rate usually above 150. So, the heart rate of 95 is normal, and no need to worry. The heart rate of 123 was not probably PSVT or SVT, but just a sinus tachycardia. If it was, then these are episodic tachycardia and return to baseline on their own. If she has repeat episodes, then she should cough hard to abort the episode and maybe neck massage if taught by a doctor after a neck examination.

I hope this helps.

Thank you.