Dear Editor,

Last week, you published a letter from a lady who had suffered a heart attack. In her letter, the lady rightly pointed out the importance of having Automatic External Defibrillators (AEDs) widely available in public places.

These devices have contributed significantly to improving outcomes for sufferers of cardiac arrest. They are very easy to use and modern automatic ones are reliable and safe.

Given their relatively cheap initial costs, it would be a good thing if the health department in line with the government, were to train people in their use and to encourage availability in both commercial and public places.

Incidentally, defibrillators don’t restart a stopped heart, they do the reverse, that is they stop a fibrillating heart. Fibrillation is when a normal heart beat and contraction are replaced by one where there is no contraction and thus no blood pressure or blood flow from the heart.

One way to imagine the difference is that fibrillation is similar to a jelly wobbling on a plate rather than a muscle contracting and relaxing efficiently. The theory then is that having stopped the fibrillation (wobbling), nature will take over and reinstate the necessary electrical activity to get things going again.

A note of caution, however, is that effective chest compressions are extremely important for any attempt at resuscitation, without which there will be no blood circulation at all.

Dr Michael Lowry

Clinical Skills Facilitator for Medical Emergencies at Leeds Dental Institute, University of Leeds, UK