Thursday 6 April 2023

My heart rate is always on a go-slow

Blood donation. 2nd one for this year. Western Cape Blood Service is in need of blood, especially from O blood groups. As an O-negative universal donor, my blood is in high demand.

I have a naturally low heart rate. It has always been low whether I'm super fit or just regular fit.

When they took my blood pressure, the machine logged me at 47bpm. This is not unusual for me but the lady was concerned. She sent me to have a juice and then tested again about 5 mins later. 53bpm. As long as the person's pulse is over 50, it is good to go. With thanks to my strong, beating heart, I filled the bag in 5:30. Another pint logged.

My slower than normal heart rate has a name - bradycardia. I've never been diagnosed but this name applies to a slower-than-expected heart rate of fewer than 60 beats per minute.

I have never had any symptoms of any underlying disease and I don't suffer from fainting, fatigue, dizziness, weakness, chest pain or difficulty breathing. I can remember taking my pulse during lectures at university and it would usually be in the 38 - 42bmp range.

A bunch of years ago - more than 10 - I went for an ECG, which was compulsory for a staged ultramarathon. At 08h30 in the morning, after having breakfast, driving to the doctor's office and getting hooked up to the machine, my heart rate was recorded at 35bpm!

Causes of a slow heart rate include genetic (family history), high level of fitness (I'm fit but not high level), meditative breathing (which I rarely do), and medication side effects (I'm not on any meds). Bradycardia can be caused by illness - an infection, low thyroid function, electrolyte imbalance, and too much potassium. Also diabetes, high blood pressure and congenital heart defects. I have none of these and no symptoms.

I need to poll my uncles on my dad's side because I'm sure I recall one of them mentioning many years ago that they have always had a slow heart rate. This leads me to think it is familial.

Whatever it is, I'm blessed to have a strong heart that allows me to do the activities that I do.