Terminology & Word Disambiguation – Overview of Vascular Diseases

00:01 Hello! This is the final lecture in the basic series of vascular medicine.

00:06 We’re going to do a very, very brief overview of all of the diseases that affect the vascular system. For those of you who go onto the advanced course, we will take each of these diseases in considerably more detail. But let’s get the overview to start with.

00:22 The learning objectives are: to understand the terminology and the word disambiguation.

00:30 That is the clarification of what the words mean. Then we’ll talk about the disease criteria, an overview of the course and an actual going through of the different diseases that are going to be covered in the advanced section.

00:45 So, of course, we’re talking about diseases that affect arteries and veins or both. And indeed we’ll also talk a bit at the end about diseases that affect the lymphatic system although those are much, much less common compared to diseases that affect the arteries and the veins, which are extremely common. As I think I’ve already stressed, for example ischemic heart disease and ischemic peripheral vascular disease are the number one causes of death in the world. And venous thrombosis, that is clots forming with pulmonary embolism, deep venous thrombosis are also exceedingly common. These are some of the commonest diseases that physicians deal with and often require hospitalization when they’re acute.

01:30 So as the blood vessels carry blood throughout the body, the vascular diseases by obstructing this or by forming clots can cause symptoms in a variety of different places in the body.

01:42 Of course in the heart, obstruction in the heart can lead to symptoms of angina, which is a pressing feeling in the chest when one tries to exert oneself. One can have symptoms in the head and neck if blood clots got to the brain. One can have problems with either upper extremity or lower extremity if one obstructs blood flow through the arteries or if one gets blood clots there. Much less common are symptoms from obstruction in the abdomen. That is the celiac, which supplies the stomach and organs around the stomach, and the mesenteric, which supplies the bowel. Those can become obstructed as well and, in fact, they can cause death of bowel tissue which is often fatal. But, fortunately, that is rare.

02:33 Let’s talk about some important terms here.

02:38 I’ve already mentioned a term, sclerosis. It’s as in atherosclerosis. Sclerosis means stiffening which is usually caused by replacement of the normal organ wall – the normal blood vessel artery wall, for example – with tissue that often has a lot of lipid in it, lots of cholesterol and also lots of scar tissue.

03:01 I’ve also mentioned embolism. Embolism means a blood clot travelling in the blood stream.

03:07 It can travel on the venous side to the lung – and then it’s a pulmonary embolism – or it can break off as we’ve talked about before from the left atrium in atrial fibrillation, travel in the body and cause a stroke or can cause kidney damage.

03:26 Thrombosis means clotting. The word thrombus means a blood clot and thrombosis is actual clotting. In thrombosis, there’s a thrombus in a blood vessel or an artery.

03:40 Stenosis is a narrowing or tightening in the blood vessel very frequently due to atherosclerosis.

03:47 Occlusion means obstruction or blocking of an artery. So, if a blood clot forms in an artery and completely obstructs the lumen, one has a total occlusion of that artery.

04:01 A dissection is a tear or a rupture in a blood vessel. This occurs in arteries and these can actually be fatal. We’re going to talk much more about them in more detail in the advanced section. But, when they tear into the blood vessel, they can actually rupture through the wall and cause fatal haemorrhage.

04:21 Necrosis is death of tissue. For example, in ischemic heart disease when the atherosclerotic narrowing gets severe and a blood clot forms and totally blocks the artery, the heart muscle – or myocardium – that’s beyond that obstruction starts to die because of lack of oxygen and nutrients. When it dies, that is called necrosis or death of tissue. And when it happens in the heart we have myocardial necrosis – that is death of heart tissue – or a heart attack: myocardial infarction.

04:54 Ischemia, on the other hand, is lack of blood flow but usually not total obstruction. So there’s lack of blood flow but the heart muscle cells survive. This is often associated with an exertional symptom called angina – that is a pressing heavy feeling in the chest when people exert themselves. But their artery is narrowed by atherosclerosis.