Louise Campbell, 27, a surveyor from West London, collapsed at the age of 15.  Her irregular heart beat is now controlled by an implanted defibrillator.

People think of heart disease as an old man’s illness.  They imagine someone who’s eaten nothing but fried food or smoked heavily for 40 years.  But I’ve been diagnosed with a heart problem since I was 15.

I was racing a friend and collapsed.  I was taken to hospital, where I was diagnosed with dilated cardiomyopathy – an enlarged heart that doesn’t pump properly – and arrhythmia, which means an irregular heart beat.

Back then, the diagnosis was more worrying for my parents than for me.  I was told again and again how lucky I was to be alive and it’s only now that I’m beginning to appreciate it.

Shortly after my eighteenth birthday I’d arranged to see my Dad for lunch.  When I went round to his flat, I discovered him dead from a heart attack.  He was 42.  It was shocking in every way – I had lost my Dad, and I realised I could die like him.

Months later I had a defibrillator implanted.  It stops my heart from beating too fast.  I tell people I’m battery operated and turn it all into a big laugh.  At airport metal detectors, it’s funny trying to explain what a defibrillator is in a foreign language.  No one expects someone in their twenties to be wearing a pacemaker.

When I first had the defibrillator I hated it, that I couldn’t control my own heart beat, let alone my life.  I was anxious about applying for a mortgage, going on holiday, everything.  At job interviews I felt I should be honest and tell potential employers about my heart, even though I’m perfectly healthy and only have check ups every six months.

Last year, for the first time, I started feeling really exhausted.  I could drag myself to work and back but that was it.  It brought home to me that I do have an ongoing medical condition, but medication to lower my blood pressure has worked really well

I don’t see my heart problems as a death sentence.  I’m not going to get obsessed with it.  After all, I could spend years worrying about my heart and die when I’m 70.

Recently I have become a founder member of a Surgery Supporters Club organised by CRY – Cardiac Risk in the Young

I think the fact that heart conditions affect young people too needs to be advertised as much as possible as even my own friends have trouble believing me!

I’ve had it so long now that it has become second nature to me but I can still remember how strongly I felt about it at first and could sympathise with those going through that now.