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Hello, my name is Iman. I'm an F one doctor. I used to be part of the Exposure Society, which is the Uni of Undergraduate Radiology Society. And I'm going to be doing a presentation on aortic dissections. So to start off with, we've got a case presentation, you got a 55 year old banker with sudden onset sharp tearing, chest pain that radiates to his back. It's worse when it started. He feels a bit sick and lightheaded on examination. He's clammy, but his chest is clear. You hear a diastolic murmur, he's a bit tachycardic hypertensive and you notice a BP difference in both arms in terms of medications, he's on ramipril and atorvastatin with chest pain, any sort of chest pain, you should have your main differentials. I have my three categories, cardiac, respiratory and other cardiac, got my A CS aortic dissection and pericarditis and a couple of others, respiratory pe pneumonia, pneumothorax. And then your other category, things like anxiety, musculoskeletal reflux. So, aortic dissection is a tear in the intimal layer of the aortic wall. That's when you get a tear in the aorta, blood tunnels into the layers of the aorta and creates a false lumen. If you can't remember any of your layers, don't worry, I've got a nice recap picture. You even in the middle, you got your tunic intima, which is the innermost layer, middle layer is your tunica media and then your outermost layer is tunica adventitia. I haven't seen these words in a very long time since dying of one. When you get a tear in one of these layers, if you get a tear in the innermost layer, then blood tunnels through, in between the tunica intima, the tunica media that can basically happen anywhere in the aorta. One of the things that I didn't appreciate in medical school was how much of an emergency this is 20% of patients die before they reach the hospital. And then every six hours that you leave a dissection, untreated, the patients mortality increase by 25%. And that jumps up to 50 24 hours just to recap anatomy and don't panic. I won't go into too much detail, but you've got your ascending aorta, your aortic arch and then your descending aorta. You've got your coronary arteries coming off the ascending and then you've got your three main branches, the brachycephalic or brachiocephalic. However, you like to pronounce it, your left common carotid and left subclavian, then you've got your aorta down the abdomen with different branches to things like kidneys and other organs. So in terms of presentation, it usually presents with severe sudden onset ripping or tearing, kind of chest pain. The thing is with aortic dissections is including myself. Most people kind of forget about them or don't think of them as a differential when it comes to chest pain. And sometimes it can just be really vague, someone can come in with, for example, a collapse. Things that might indicate you towards a dissection of risk factors like age being between 5070 males, hypertension is the one that they like to test you on in med school and then connective tissue disorders. So if someone has something like mins, in terms of clinical findings, you might feel a weak or absent carotid brachial femoral pulses, you might get a difference in BP in both arms. It's not always a thing that happens. But if it's absent, don't think it isn't a aortic dissection. And what we mean by a difference is a difference in 20 systolic, you might have a new aortic regurgitation. They might present with hypertension or hypotension. And then depending on which arteries are involved in the dissection. For example, there's coronary arteries, you can get angina, spinal arteries, you can get paraplegia, that kind of thing. The way I kind of think about it is physically where the dissection is in the aorta. So the a if the dissection is near the ascending aorta and affecting the right coronary or the coronary arteries, then you might get chest pain. Remember there's an aortic valve. If it's near that or affecting it, then you get a heart murmur. If it's, for example, if the dissection propagates towards the renal arteries and it compresses on it, then you can get an AK because your kidneys aren't being confused. Similarly, if it's your affecting your mesenteric artery, you might get abdominal involvement. So it just depends on where that dissection is. In terms of investigations, you've got your ECG to check for heart involvement, chest X ray, which we will go through what you might see on one and then your basic bloods. So full blood count, user knees, LFT S, full blood count, check the bleeding, user knees again, renal involvement. AKI LFT to check for hepatic involvement, you want to go and save and a cross match with the bleeding, a phone in to check for chest involvement, heart involvement and then a VG or VG to check for lactate. Your gold standard investigation is a CT angiogram of your whole aorta. But that's only if the hemody you can get them to the CT scanner. If they're unstable, then you might want to do a transthoracic echo or a transesophageal echo. That just depends on if you have people that are trained in it. So chest X ray findings, this one's a normal chest X ray. You got your aortic knuckle and on this side, you've got your abnormal chest X ray and you can see you got a, you have a widened mediastinum and you get that loss of the contour of the aortic knuckle. Here. Thing to run below is that 10% of these might actually be normal. This is just a quick recap. Transthoracic echo is noninvasive. It's basically just the transducer of being on your chest. And then the transesophageal one is the, is where they actually feed that transducer down your throat and that's more invasive. Hence why I was saying it only depends on if you have someone trained in doing it and if you have the resources, so you've got two types of dissections. Stanford type A and type B type A is when the ascending aorta is involved plus or minus the aortic arch or the descending aorta. And type B is where it only involves the descending aorta and anything below that basically type A needs surgery and type B is medically managed plus or minus elective surgery. So any sort of emergency management you want to do your at. This is one of the few conditions where you actually do need two large more cannulas, an early senior escalation. You don't want to be managing this on your own. You might need critical care. You might need, you probably will need the interventional radiology, vascular surgeons, cardiothoracic surgeons and your anesthetist analgesia again, is one that we all forget we fix the patient or try to fix the patient and forget that they're in pain and vitally, they need BP control tight BP control. The first line we use is IV beta blockers like labetalol. And then second line is something like a calcium channel blocker. And depending on what type of dissection you have, if it's type A, then it's open surgery and then type B is where it can be managed medically, you know, with BP control, lifestyle management. And then later on potentially an elective surgery like TIVA, which is a radiologically inserted, stent into the aorta. That was quite a lot of content. But just to summarize an aorta dissection is when you get a tear in the intimal layer of the aorta and then blood tunnels into the walls of the aorta. This is a medical emergency. It can present with a tearing, sudden chest pain that radiates to the back in the exams. If they ask for a first line investigation, it's gonna be a chest X ray. But your gold standard investigation, if they are stable is CT angiogram aorta, you've got two types of aortic dissections, type A is managed surgically and type B is medical plus or minus elective surgery. I hope that covers everything. Thank you for listening.
