Atrial Fibrillation: a silent but deadly condition

Fit mother of two discovered huge risk of stroke after routine heart screening

Sinéad Hamill at her home in Stillorgan. Photograph: Cyril Byrne

Sinéad Hamill at her home in Stillorgan. Photograph: Cyril Byrne

Tue, Mar 19, 2013, 06:00

I was a fit and healthy child and teenager, playing volleyball, basketball and tennis in school and riding horses until I was pregnant with my second child, Dawn, who was born five years ago.

In fact, we are a fit family. Dawn and her sister, Hazel (8), play Gaelic football and swim. Hazel also plays tennis and basketball and is in an athletics club. My husband, Tony, does triathlons and I play Gaelic football and run in marathons.

I took the free HeartBeat screening after I received an offer with the annual renewal letter from my private healthcare insurance provider, Laya. I hadn’t had any annual health check-ups in recent years so I just decided to go along for the screening in July of last year.

Electrical malfunction
My blood pressure was taken. My BMI (Body Mass Index) was calculated and I was given an electrocardiograph test. The nurse immediately said that she noticed an irregularity on the ECG readout. I then went into the doctor who asked me about my exercise levels.

I explained that I was training for the Dublin marathon in October and was planning to ramp up to longer runs over the next three months. He explained how the ECG showed that I had atrial fibrillation (an electrical malfunction in the heart beat) and that I needed to see a cardiologist to have it sorted out.

The HeartBeat team faxed my GP the results of the screening and he rang me back straight away. He knows I run and is fairly fit himself but he explained how important it was that I have the irregularity investigated. “It’s a little more than a heart murmur. You’ll have to stop running and football training until you find out what’s causing it,” he told me.

He gave me a prescription for a form of aspirin to thin the blood while I awaited an appointment with a cardiologist.


Valve defects
Of course I Googled the condition and realised that while the more common form of AF was a racing heartbeat (with more than 200 beats a minute) and palpitations, I had a form in which my heart skipped a beat every one in four beats. I still had to find out what was causing it.

The cardiologist did an echo ECG which didn’t show up any valve defects or fibroids in my heart. What it did show though was the lower chamber of my heart was enlarged. We discovered there wasn’t enough blood being pumped down from the upper chambers (right and left atria) into the lower chambers of my heart (right and left ventricles).

The problem with this is that a blood clot can form if the blood is not being pumped enough and this clot can be passed out of the heart into another part of the body. If the clot lodges in an artery in the brain, this can cause a stroke. I was told that I was five times more likely to have a stroke than most people.

Meanwhile, I got all of my family – my three sisters and my brother – to have ECGs to check if they also had the condition. It turned out that they hadn’t so that ruled out a genetic component even though our mother died of a stroke and heart attack at 73. She also had high blood pressure and smoked, neither of which I had.

The cardiologist suggested I have a cardiac MRI scan to check that there was no underlying fault in my heart. Meanwhile, he prescribed a stronger blood-thinning medication.

The MRI scan didn’t show up any fault in my heart. The next step was to have a cardioversion, a procedure under general anesthetic which would send an electric shock through my heart to get it to stay in rhythm. I was told that there was a 50 per cent chance that this operation would bring my heart beat back to normal but that the longer one had atrial fibrillation, the less likely it would work.

I was much younger than any other patients who have the operation but I still didn’t know how long I had the condition.

Within five days of the operation, I knew my heart had gone out of rhythm again. I felt sluggish. I got up and sat on the bed, took my pulse and could feel my heart out of rhythm again. Another cardioversion operation was scheduled for six weeks after the first and while that worked, the cardiologist also put me on betablockers to keep my heart in rhythm.

Betablockers
On a more recent check-up with the cardiologist, my betablocker prescription was reduced from two tablets a day to one and I will have to take these for the rest of my life. My blood-thinning medication was also changed to a lower dose one.

The only other option for me is to have pulmonary aversion – a surgical procedure which will cauterise a vein at the back of my heart to change the electrical signal from the top to the bottom chamber. While I don’t like the idea of being on medication for the rest of my life, I don’t have any symptoms at all so the cardiologist sees no rush to do such a procedure.

The cardiologist has told me that 50 per cent of people with atrial fibrillation don’t have any symptoms, but it’s the biggest cause of stroke. Yet because my heart is perfect – apart from the electrical malfunction in its beat, the chances of me having a stroke are much less than other people with AF who have defects in their heart as well.

Overall, I have been told that my fitness levels have helped me. I’m back running again and back playing football. I haven’t decided for definite yet, but I plan to do the Dublin Marathon in October.