pacemaker - davidrobertsblog.com

Anyone who meets me would probably think that I am a very healthy individual. I have felt very well this year and have been very active doing exercise routines most days, swimming in the summer in the sea and rivers, gardening, painting and decorating, and doing quite a lot of walking etc.

Hidden problems

However, I have a couple of hidden health problems. The most serious of these is a heart problem which might have been fatal had it not been for the intervention of the National Health Service. However, thanks to them, I am able to live a normal life.

What the National Health Service has done for my heart

After a series of in hospital investigations (I was in a hospital for a fortnight) it has implanted under the skin of my chest just under my left collarbone a device called an ICD which is a kind of pacemaker, though, in fact, it’s an unusually sophisticated one. Wires go from it and are inserted into my heart.
The other main thing is that the NHS has put me on two medications.
After I came out of hospital I was offered a series of cardiac rehab classes and lectures about heart health. I also see a cardiac consultant to check on how I am getting on and every six months I am in touch with the pacemaker clinic which checks that the pacemaker is functioning correctly and that the battery is good for a year or more.

My racing heart – The diagnosis – ARVC

All this means is that I have got is a disturbance of the heart rhythm. This is called arrhythmia.

In practical terms what this means is that my heart may, at times, beat irregularly, or too fast, or too slow. If these irregularities take an extreme form then they can be life-threatening. My heart has been recorded at beating at over 200 beats per minute and as low as 26 beats per minute. if these rates had been maintained for a period of time I would have been dead by now.

When my pulse has been taken in recent years at a doctor’s surgery usually the heart rate has been around 40 to 45 beats per minute. I was always told this was very good and is the speed that a very fit person or an athlete would expect. Apparently the resting heart rate for most people is around 60 beats per minute.

It seems that what happened in December 2018 and February 2019 was that my heart rate went extremely high and made me feel dizzy. The doctors considered this was dangerous which is why I was taken into hospital for check-ups and monitoring and a remedy.

Cardiomyopathy

So the diagnosis now is ARVC. These letters stand for “arrhythmic right ventricular cardiomyopathy”. The right ventricular bit simply means that the problem is in the lower right chamber of my heart.

Cardiomyopathy means “disease of the heart muscle” but it is not disease in the sense of something attacking it or that it is growing in some exceptional way. Cardiomyopathy normally takes one of two forms, either a thickening of the muscle (wall) of the heart or a thinning of the muscle. In my case it seems that the wall of the right ventricular chamber is thinner and weaker than it should be. The normal effect of this would be that a person experiences breathlessness. I have never experienced this so my conclusion is that any problem there must be fairly slight.

However, the other effect of some sort of abnormality of the heart such as I have is that vital electrical currents, which cause the heart to beat, don’t flow as well as they should across pathways in my heart. This is what leads to irregularities in my heart rate/pulse.

Cardiomyopathy can lead to sudden, unexpected death.

Medication, a device and follow-up education

I take a drug called Bisoprolol which reduces the amount of adrenaline my body produces and thereby it should steady my heart rate.
If my heart should happen to go much too fast then the muscle of the heart would be unable to pump blood through my lungs to get it oxygenated in the normal way. If the movement of blood slows down for a period of time it can start to thicken up and form a blood clot which could lead to a stroke or death. For this reason I take another tablet called Rivaroxaban which is an anticoagulant which stops my blood from getting thicker.
The third “treatment” that I have is a very specialised kind of pacemaker called an ICD. ICD stands for “implantable cardioverter defibrillator”. This has several functions and can be adjusted electronically.

The functions of my pacemaker

The first is to ensure my heart doesn’t go too slow and currently it is set to prevent my heart from going slower than 50 beats per minute.

ICD’s built-in accelerometer

It also has a function called an accelerometer. This senses the movement of my chest and decides if I need a boost to the speed of my heart to obtain sufficient oxygen for the activity it has sensed. If it thinks I need more oxygen it will deliver minute electric pulses to my heart to speed it up.

Defibrillator

The third function is to work as a defibrillator which means that if the speed of my heart goes way out of control or it stops altogether it will deliver a strong electric shock to start a heart again, hopefully with a normal rhythm.

A final thing is that the ICD stores a record of my heartbeats and understands if something unusual is going on. If it senses a problem it will send a message over the mobile phone network to the pacemaker clinic in the Royal Sussex Hospital in Brighton. The clinic can then take any action it thinks is necessary including alerting the cardiac consultant and my doctor. Every night my pacemaker communicates with a transmitter in my bedroom. It’s like having a spy in my chest.

Monitors heart activity and reports automatically by mobile phone network

It was because this facility functioned in June 2019 that the hospital realised the atrial chamber was malfunctioning and that is why I was put on the anticoagulant. So the pacemaker diagnosed the problem and alerted the doctors. Without it I would not have known that I needed further medication.

Is the pacemaker working correctly?

Maybe not. Although I’ve been feeling very well this year my main concern has been that my heart rate sometimes seems to go up very high and for no good reason. The problem occurs if I jog or do any movement which involves my chest going up and down relative to the ground in such exercises as squats or skipping or jogging. In a few seconds my heart rate can go from 70 beats per minute to 130 beats per minute, even though I am not the slightest bit out of breath.

When I went to cardiac rehab classes at the Princess Royal Hospital in Haywards Heath shortly after I had the pacemaker inserted I was advised that a safe heart rate for me to exercise at was between 90 and 105 beats per minute.

My own heart rate monitor

I would never have known about this speeding up of my heart rate if I hadn’t bought a high quality heart monitor, the same brand that they use in the hospital cardiac rehab classes. (Polar)

The follow-up to having my my pacemaker insertion has included visits to a cardiac consultant. I told him that I was puzzled about why my heart was suddenly speeding up so much when it didn’t seem to need to do this. He suggested that he reason it may be speeding up might be because of a device within the pacemaker called an accelerometer. He suggested that when I next had an appointment at the pacemaker clinic in Brighton I should ask them if an adjustment might be made.

In fact I went to the pacemaker clinic on the 4th of November and I will write about this experience in due course.

David Roberts

www.davidrobertsblog.com

27 November 2020

British Heart Foundation

For more information and to donate to The British Heart Foundation Click Here

The cardiomyopathy charity

In the UK one organisation specialises in cardiomyopathy. For more information about cardiomyopathy click here.

NHS cardiomyopathy advice and information

And the NHS website is valuable too. It points out that ” Hypertrophic cardiomyopathy is the most common cause of sudden unexpected death in childhood and in young athletes.” The NHS cardiomyopathy website page.

British Heart Foundation – Why I support it