Statins have dominated the cholesterol-lowering field for some years but last week the results of an international trial of Evolocumab, one a new breed of medicines for reducing cholesterol, was hailed as a breakthrough. Professor Peter Sever, one of the leaders of the trial, explains how Evolocumab differs from statins and Dr Margaret McCartney takes a look at the trial.

You may have noticed them in work places, gyms, and other public spaces but do you know how and when to use a defibrillator? Every time someone has a cardiac arrest and CPR is performed we should also be running for the nearest defibrillator. But currently this only happens in 2-3% of cardiac arrests, putting thousands of lives at risk every year. Mark speaks to teacher Erica Melsom and the pupil, Alex Cowes, whose life she saved by using the school defibrillator. Professor Gavin Perkins explains why and when we should run and get one. And Mark demonstrates just how simple they are to use, even if you've never touched one before.

Posttraumatic Stress Disorder, a psychological condition which can begin after a traumatic event and last for many years, is the equivalent for your cardiovascular system of smoking 10 cigarettes a day. Dr Donald Edmondson explains how extreme stress takes a toll on our arteries.

More than 80% of pregnant women take at least one prescribed medication and yet very few of these drugs are actually licensed for use in pregnancy. Mark talks to Professor Anna David about why there has been a reluctance to license medications for use in pregnancy, what impact that has for pregnant women, and what needs to change.

Producer: Lorna Stewart.