Okay, so I'm on holiday this week i'm doing a science competition at the end of the week it's basically like an x-factor for science teachers! The backstage area is going to be mental so i have to do a 3-minute talk on anything science related i've come up with, this idea all you need Is an umbrella and a pair of pliers and that's enough to teach anyone about a disease of the heart! Luckily, most doctors are not superstitious you could say
That our head rules our heart but there is a condition of the heart that leads to a five times Increased risk of a stroke; a clot in the brain we call this atrial fibrillation and it's extremely common as an emergency doctor i see in 5% of patients that come to a&e.
So let me tell you about it Your heart is a beautiful muscular pump with a central muscular wall separating the right side from the left side. It is made up of four chambers, two chambers at the top called the atria and you have the right atrium and the left atrium Whose job it is when they contract to fill the two large chambers at the bottom called the ventricles, the right ventricle and the left ventricle. So, when the ventricles contract the blood, from the right ventricle travels round to the lungs for oxygenation It returns to the left atrium The left atrium, when it contracts Fills the left ventricle. So all that oxygenated blood then gets pumped out of the left ventricle around the whole body, yes including the brain. This is called the cardiac cycle. And we've all done this about a hundred times since i've been talking.
Like, any pump the heart needs to be well coordinated look at how beautifully smoothly this umbrella collapses So the air getting pushed out would have an equally smooth flow, all because of the coordination between the runner and the Stretcher. I had to google these terms but in the heart they're called the sinoatrial node and the electrical conduction system. In atrial fibrillation things don't run quite as smoothly These pliers represent long-term damage from high blood pressure and ischemic heart disease; which is a disease of the blood vessels of the heart So now, we have poorly coordinated contractions of the atria this is atrial fibrillation.
The loss of the coordination of the contractions, means the heartbeat now becomes irregular and our previous lovely smooth flow of blood is now disrupted. This causes pockets of blood that are no longer moving and when blood doesn't move it clots. If this clot forms in the left atrium it may become dislodged and go into the left ventricle It can then be pumped out of the left ventricle and round the body as we talked about and it can end up in the head thus causing an ischemic stroke So this is how a disease of the heart atrial fibrillation can lead to a problem in the brain; giving you an increased risk of stroke.