arterial dissections involving the superior mesenteric artery, celiac artery, renal arteries, hepatic artery and others. when they are an extension of an aortic dissection, this condition is managed simultaneously with aortic treatment. in isolation, visceral artery dissections are discovered incidentally in up to a third of patients and in these cases my be managed medically by a vascular surgeon. in cases where the dissection results in organ damage it is generally accepted by vascular surgeons that surgery is necessary. surgical management strategies depend on the associated complications, surgical ability and patient preference. mesenteric ischemia mesenteric ischemia results from the acute or chronic obstruction of the superior mesenteric artery (sma). the sma arises from the abdominal aorta and usually supplies blood from the distal duodenum through two-thirds of the transverse colon and the pancreas. chronic mesenteric ischemia the symptoms of chronic mesenteric ischemia can be classified as abdominal angina which is abdominal pain which occurs a fixed period of time after eating. due to this, patient's may avoid eating, resulting in unintended weight loss. the first surgical treatment is thought to be performed by r.s. shaw and described in the new england journal of medicine in 1958. the procedure shaw described is referred to as mesenteric endarterectomy. since then, many advances in treatment have been made in minimally invasive, endovascular techniques including angioplasty and stenting. acute mesenteric ischemia acute mesenteric ischemia (ami) results from the sudden occlusion of the superior mesenteric artery. renovascular hypertension the renal arteries supply oxygenated blood to the kidneys. the kidneys serve to filter the flood and control blood pressure through the renin-angiotensin system. one cause of resistant hypertension is atherosclerotic disease in the renal arteries and is generally referred to as renovascular hypertension. if renovascular hypertension is diagnosed and maximal medical fails to control high blood pressure, the vascular surgeon may offer surgical treatment, either endovascular or open surgical reconstruction. cerebrovascular disease carotid ultrasound. carotid endarterectomy. vascular surgeons are responsible for treating extracranial cerebrovascular disease as well as the interpretation of non-invasive vascular imaging relating to extracranial and intracranial circulation such as carotid ultrasonography and transcranial doppler. the most common of cerebrovascular conditions treated by vascular surgeons is carotid artery stenosis which is a narrowing of the carotid arteries and may be either clinically symptomatic or asymptomatic (silent). carotid artery stenosis is caused by atherosclerosis whereby the buildup of atheromatous plaque inside an the artery causes narrowing. symptoms of carotid artery stenosis can include transient ischemic attack or stroke. both symptomatic and asymptomatic carotid stenosis can be diagnosed with the aid of carotid duplex ultrasound which allows for the estimation of severity of narrowing as well as characterize the plaque. treatment can include medical therapy, carotid endarterectomy or carotid stenting. the society for vascular surgery publishes clinical practice guidelines for the management of extracranial cerebrovascular disease. less common diseases involving cerebral circulation treated by vascular surgeons include vertebrobasilar insufficiency, subclavian steal syndrome, carotid artery dissection, vertebral artery dissection, carotid body tumor and carotid artery aneurysm among others. peripheral artery disease peripheral artery disease pad is the abnormal narrowing of the arteries which supply the limbs. patients with this condition can present with intermittent claudication which is pain mainly in the calves and thighs while walking. if there is progression, a patient may also present with chronic limb threatening ischemia which encompasses pain at rest and non-healing wounds. vascular surgeons are experts in the diagnosis, medical management, endovascular and open surgical treatment of pad. a vascular surgeon may diagnose pad using a combination of history, physical exam and medical imaging. medical imaging may include ankle-brachial index, doppler ultrasonography and computed tomography angiography, among others. treatments are individualized and may include medical therapy, endovascular intervention or open surgical options including angioplasty, stenting, atherectomy, endarterectomy and vascular bypass, among others. illustration of atherosclerosis causing arterial obstruction which clinically presents at peripheral artery disease. abi testing is used by vascular surgeons in the diagnosis of pad. the blood pressure in the arm and leg are compared as a ratio. angioplasty (pictured) and stenting are two endovascular treatments employed by the vascular surgeon. management of venous diseases chronic venous disease chronic venous insufficiency is the abnormal pooling of blood in the lower extremity venous system which can lead to reticular veins, varicose veins, chronic edema and inflammation among other things. population data suggests that chronic venous insufficiency affects up to 40% of females and 17% of males. when chronic insufficiency leads to pain, swelling and skin changes it is referred to as chronic venous disease. chronic venous insufficiency (cvi) is distinguished from post-thrombotic syndrome (pts) in that cvi is primarily an issue of valvular incompetence of the superficial or deep veins whereas pts may occur as a long-term complication of deep venous thrombosis. the vascular surgeon has several modalities to treat lower extremity venous disease which including medical, interventional and surgical procedures. for instance, venous ulceration may be treated with unna's boots, superficial venous reflux with radiofrequency, laser ablation or vein stripping if indicated. when indicated, insufficiency in the deep veins may be treated with reconstruction of the venous valves with internal or external valvuloplasty. varicose veins a medical illustration of lower extremity varicose veins. lower extremity varicose veins is the condition in which the superficial veins become tortuous(snakelike) and dilated (enlarged) to greater than 3mm in the upright position. incompetent or faulty valves are often present in these veins when investigated with duplex ultrasonography. vascular treatments can include compression stockings, venous ablation or vein stripping, depending on specific patient presentation, severity of disease, among other things. nonthrombotic iliac vein lesions nonthrombotic iliac vein lesions (nivl) include may-thurner syndrome (mts) whereby there is compression of the left iliac venous outflow usually by the right iliac artery leading to left leg discomfort, pain, swelling and varicose veins. nivl encompasses compression of the iliac veins on either the right or left side. vascular surgeons may offer different treatment modalities depending on the patient presentation. minimally invasive diagnostic and therapeutic options might include intravascular ultrasound, venography and iliac vein stenting whereas surgical management may be offered in refractory cases. surgical management strategies involve reconstruction or bypass of the affected segment such as cross-pubic venous bypass, also known as the palma procedure. deep vein thrombosis deep vein thrombosis (dvt) is the formation of thrombus in a deep vein. dvt is more likely to occur in the lower extremity than the upper extremity or jugular vein. when a dvt involves the pelvic and lower extremity veins it can sometimes be classified as an iliofemoral dvt. some evidence to suggests that performing an intervention in these cases may be beneficial whereas other evidence does not. overall, the data shows that there may be a reduction in the incidence in post-thrombotic syndrome in patients who undergo certain procedures for iliofemoral dvt but it is not without risks. a vascular surgeon may offer venogram, endovascular suction or mechanical thrombectomy and in some cases pharmacomechanical thrombectomy. some lower extremity dvt can be severe enough to cause a condition called phlegmasia cerulea dolens or phlegmasia alba dolens and can be limb-threatening events. when phlegmasia is present, intervention is often warranted and may include venous thrombectomy. post-thrombotic syndrome post-thrombotic syndrome (pts) is a medical condition that sometimes occurs as a long-term complication of dvt and is characterized by long term edema and skin changes following dvt. presenting symptoms may include itchiness, pain, cramps and paresthesia. it is estimated that between 20% and 50% of patients will experience some degree of pts. a treatment strategy for pts may involve the use of compression stockings. pulmonary embolism surgical management of an acute pulmonary embolism (pulmonary thrombectomy) is uncommon and has largely been abandoned because of poor long-term outcomes. however, recently, it has gone through a resurgence with the revision of the surgical technique and is thought to benefit certain people. chronic pulmonary embolism leading to pulmonary hypertension (known as chronic thromboembolic hypertension) is treated with a surgical procedure known as a pulmonary thromboendarterectomy. compressive venopathies compression of large veins by adjacent structures or masses may lead to distinct clinical syndromes including may–thurner syndrome (mts), nutcracker syndrome and superior vena cava syndrome to name a few. treatment modalities include venography, intravascular ultrasound and venous stenting as well as more invasive open venous reconstruction and bypass. management of hemodialysis access patients with chronic kidney disease may have progression of disease which requires renal replacement therapy to filter their blood. one strategy for this therapy is hemodialysis, which is a procedure that involves filtering a patient's blood to remove waste products and returning their blood back to them. one method which avoids repeated arterial trauma is to create an arteriovenous fistula (avf). the first procedure described for this purpose is named the cimino fistula, after one of the surgeons who first had success with it. vascular surgeons may create an avf for a patient as well as undertake minimally invasive procedures to ensure the fistula remains patent. management of vascular trauma one way that vascular trauma may be understood is by categorizing vascular injury by three criteria: mechanism of injury, anatomical site of injury and contextual circumstances. mechanism of injury refers to etiology, e.g. iatrogenic, blunt, penetrating, blast injury, etc. anatomical site functionally refers to whether there is compressible versus non-compressible hemorrhage, while contextual circumstances refers to injuries sustained in the civilian or military realm. each context can be further broken down: military into combatant vs. noncombatant and civil into urban vs rural trauma. this categorization scheme is of both epidemiologic and clinical significance. for instance, arterial injury in military combatants currently occurs predominantly in males in their twenties who are exposed to improvised explosive devices or gunshot wounds; whereas in the civilian realm, one study conducted in the united states showed the most common mechanisms to include motor vehicle collisions, firearm injuries, stab wounds and falls from heights. blunt thoracic aortic injury advances in vascular surgery, specifically endovascular technologies, have led to a dramatic change in the operative approach to blunt thoracic aortic injury (btai). btai results from a high speed insult to the thorax such as a motor vehicle collision or a fall from a height. one widely-used classification scheme is based on the extent of injury to the anatomic layers of the aorta as seen with computed tomography angiography or intravascular ultrasound. grade 1 btai are those which tear the aortic intima; grade 2 injuries refer to intramural hematoma; grade 3 injuries are pseudoaneurysm and are only contained by adventitial tissue; and grade 4 refer to free rupture of blood into the chest and surrounding tissue. when indicated, first line intervention involves tevar. investigations major trials namenumber ofpatientsdescription netherlands vascular study multicentre aneurysm screening study (mass)found reduced mortality after screening for abdominal aortic aneurysms in the uk. uk small aneurysm trial1090aaa 4–5.5 cm; immediate surgery vs. ultrasound surveillance (and treatment for rapid expansion or aaa >5.5); 30-day mortality after elective aaa repair is 5.8%. no difference in survival. adam va cooperative group trial73451patients in va screened with no known history of aneurysm; age 50–79; aaa 4.0-5.4 cm; similar conclusion to uk small aneurysm trial. joint vascular research group trial284studied the relationship between intraoperative intravenous heparinization, blood loss during surgery and thrombotic complications. conclusion: intraoperative heparin, given before aortic cross-clamping, is an important prophylactic against perioperative mi in aortic aneurysm surgery. north american symptomatic carotid endarterectomy trial (nascet)1415showed carotid endarterectomy was beneficial in symptomatic patients. two year stroke rate in patients with > 70% carotid stenosis decreased from 26% to 9%. two year stroke rate in patients with > 50% decreased from 15% to 9%. asymptomatic carotid atherosclerosis study (acas)1662demonstrated benefit in asymptomatic patients with >60% stenosis. five year stroke rate reduced from 11% to 5.1% with carotid endarterectomy. training previously considered a field within general surgery, it is now considered a specialty in its own right. as a result, there are two pathways for training in the united states. traditionally, a five-year general surgery residency is followed by a 1-2 year (typically 2 years) vascular surgery fellowship. an alternative path is to perform a five or six year vascular surgery residency. in many countries, vascular surgeons can opt for additional training in cardiac surgery as well as post-residency. programs of training vary slightly between different regions of the world. country standards bodies