Welcome to Dr. Warrick's podcast channel. Warrick is a practicing cardiologist and author with a passion for improving care by helping patients understand their heart health through education. Warrick believes educated patients get the best health care. Discover and understand the latest approaches and technology in heart care and how this might apply to you or someone you love. Hi, my name is Dr. Warrick Bishop and welcome to my podcast channel. Well, DVT, PE and Factor V Leiden. Well, what's all that about? Well, I'm pretty sure most of you will have heard about DVT. DVT stands for Deep D Vein V Thrombosis T. And thrombosis means a So DVT is a clot in the deep veins. Now this normally relates to the legs, but you can get a DVT in the arms in certain circumstances. For example, an injury to an arm could lead to that, or a mobilisation of the arm for some reason. Let's stick with DVT in the leg though, because really that's far and away the most common. Well, if a clot forms in the leg, in one of the deep veins, what happens? Well, blood return won't be as good as it should be, and the leg may well swell, may well be painful, a little bit red. The ache may be like a muscle tear or a muscle ache, but the leg will look a bit different and not feel quite right. Well, how do we diagnose a deep vein thrombosis if it's there? Pretty simply, we need to use an ultrasound, which is a way that we can look at blood flow through the legs with a simple transducer that we put on the leg, on the skin. A very straightforward process. So DVT, a clot in the leg. Achy legs which can be a bit red and swollen. And picked up an ultrasound. Well we treat it by thinning the blood. Principally we thin the blood so that the clot doesn't extend. We don't give people drugs to break the clot down. Because it turns out that the body breaks the clot down itself. And if therapeutically we simply stop the body from extending that clot. The patient's own body systems will clear the clot all in good time. Now we treat people for about three months generally for an average deep vein thrombosis. Okay, well that's pretty straightforward. Can deep vein thrombosis go wrong? Well, you bet it can. It can extend, it can get longer. And occasionally that clot in the leg can break off in the leg. And with the rest of the blood, travel back to the right side of the heart, through the right side of the heart, and into the lungs. Now because the lungs have smaller blood vessels compared to where the deep vein thrombosis came from, then the clot, that thrombus tissue, gets caught within. the blood vessels of the lungs it doesn't get through the lungs oxygenated into the left side of the heart and then pumped around the body the clot gets stuck in the lungs that is called a pulmonary pulmonary relating to lungs embolism embolism meaning a clot that's come from somewhere else and moved so a p e pulmonary embolism well this can be This can actually be life-threatening. People can die from pulmonary embolism. So how do we pick it up? Well, sudden onset of shortness of breath, collapse, death. People do have profound pulmonary embolism from big clots in the legs and they can be found dead in hospital and resuscitated. So death can be a presentation which is frightening. Sometimes a fast heartbeat, what we call tachycardia. Very occasionally pain and very occasionally people may cough up a little bit of blood if there's been damage to lung tissue and that damage is represented as a little bit of blood leaking into the airways. Well, this pulmonary embolus is a life-threatening event and we need to diagnose it as quick as possible. using a CT scanner or a CAT scanner, pulmonary pertaining to lungs, angiogram, looking at the blood vessels, a CT pulmonary angiogram. And by doing that, we can physically look directly at the pulmonary arteries and see if there's clot within them. This is a really quick test, very accurate, occasionally for people who have bad kidneys where we can't. give a contrast load because we may worsen the kidney function we can use a nuclear medicine scan where we literally look at how the air moves into the lungs using a special isotope and we compare that with how the blood moves through the lungs using a different isotope and we match those up and see if there's a mismatch between how much air is getting in. and how much blood is being supplied. And if there's not enough blood being supplied, then that implies to us that there's been a pulmonary embolism. So pulmonary embolism, very serious. How do we treat it? Well, again, we thin the blood. Occasionally, if it's a significant pulmonary embolism, we do put in drugs that bust up the clot. But there are specific characteristics that someone has to have for that to be the case. Issues with the way the right side of the heart is working. If it's overloaded. If there's features of failure. There's a couple of characteristics and criteria we go through. But generally we always will use a blood thinner. Occasionally the clot busters. But always the blood thinners. And we'll run those blood thinners for a minimum of six months. And in some cases. we may run those blood thinners for life. Because we've observed that in about 30% of patients without a clear reason or provocation for their pulmonary embolism, and obviously their DVT prior to that, that they'll get a recurrence. And so using blood thinners long term for those individuals makes a lot of sense. Well, who would be at risk? Well, it turns out that as people age, they're at greater risk of having clot formation, particularly issues around immobility. If you're sick and laid up in bed, if you've had surgery and not moved very much, and travel, we talk about cattle class travel. So scrunched up in a plane on a long-haul flight, maybe on a train or a long-term car ride or bus trip. So immobility. Pregnancy increases the risk of deep vein thrombosis. It's an important aspect to keep an eye on. Obesity because it reduces the way blood can return to the heart. Smoking increases the ability or the propensity of blood to... stick together. So smoking increases a risk and the oral contraceptive pill can increase risk of DVT as well. Obviously if you've injured the vein that may lead to damage within the vein and clot forming as well. There's a number of cancers which can alter the way the blood clots and increase the likelihood of clot formation. So an important side issue in the treatment of cancer. But really importantly, and what I'd like to touch on today, is that 30% of these individuals will be found to have a hereditary cause. And that means that they've inherited a predisposition for formation of a DVT and therefore the risk of a pulmonary embolism from their families. The most common of those is one called Factor V Leiden. Now, Leiden isn't the name of the person who discovered it, and it's not the name of the protein. It's in fact the name of the Dutch city where the researchers were located when they discovered this factor abnormality in 1994. And just by way of a little bit of background, We all have a number of different components. I'm going to call them factors that work together to cause clots to form in the body. So if we cut ourselves, these factors come into play and make sure we clot so we don't bleed to death. Because if we cut ourselves, we need to repair the hole. We need the blood to stop leaking out. Well, that coagulation pathway, that coagulation process, is also regulated by a process that keeps the blood thin. So we don't accidentally clot our whole bodies. Because it would be terrible if we had a cut, kicked off a clot formation, and that clot just extended and perpetuated right through our entire body. So obviously we have a regulator to stop. clot extending too far. That's the fibrinolytic system or the non-clot or anti-clot system. Well, factor V laden is a mutation or an abnormality of the individual's normal factor V. And what should happen with a normal factor V is a protein. in the non-clotting system called protein C, should interact with factor V to regulate ongoing clot formation. So in factor V-laden, the blood factor V does not interact with the clot-preventing protein. and therefore there's a greater chance of clot being formed. I hope that makes sense. Factor 5-Laden is the most common of the hereditary clotting risks. There are a number of others. It has to be considered in patients who are relatively young and having clots. Certainly it's a concern in women during pregnancy, and particularly if they're on the oral contraceptive pill with an estrogen component. And of course, we'd recommend not to smoke for these people. An interesting one from a cardiological perspective is Factor V Leiden has not been linked with non-valvular atrial fibrillation stroke, although you might think that these people are at increased risk of forming clots. Well, the diagnosis is the same as for people with pulmonary embolus or DVT from any other cause. And really the treatment is pretty similar as well. We use predominantly blood thinners. Occasionally long term, but mostly intermittently. So there you go. A little bit about DVT, PE, factor 5 laden. And I hope you've found that informative. Please, if you have any queries or questions, drop us a note. You know the email. Thank you so much for joining me. I do wish you the very best. Till next time, stay well. Stay happy and please don't die from a heart attack. Take care and goodbye. You have been listening to another podcast from Dr. Warrick. Visit his website at drWarrickbishop.com for the latest news on heart disease. 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