L3, CVS Pathology PDF

pathology - CVS Aneurysms & diseases of veins LECTURE (3) Aneurysms & diseases of veins Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins DEFINITION  Dilatati...

pathology - CVS Aneurysms & diseases of veins LECTURE (3) Aneurysms & diseases of veins Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins DEFINITION  Dilatation of the wall of blood vessels. ① Weakening of the vessel wall or extracellular matrix. CONGENITAL  Berry aneurysms of brain (circle of wills). TRAUMATIC  Arterio-venous fistula.  Vasculitis, infections and emboli of subacute bacterial INFLAMMATION endocarditis.  especially of vascular smooth muscle cells. PATHOGENESIS DEGENERATIVE  as in atherosclerosis and hypertension. INADEQUATE  Marfan syndrome CT SYNTHESIS  Ehlers-Danlos syndrome. ② Stretching of the weakened wall by increased pressure.  Hypertension Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins ① ACCORDING TO THE WALL OF ANEURYSM TRUE  The wall involves all layers of the artery. FALSE  The wall is not the vessel wall.  It may be fibrous tissue after rupture of artery and formation of extravascular hematoma that communicates with the intravascular space. ② ACCORDING TO THE SHAPE SACCULAR TYPE  Wall bulges outward but is otherwise intact. True FUSIFORM TYPE  Circumferential dilation of vessel.  Blood has entered the vessel wall, as from a tear in the intima, and has DISSECTING separated (dissected) the layers. Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins 1 Aortic aneurysms PREDISPOSING ① Atherosclerosis. CONDITIONS ② Hypertension. ① Atherosclerosis-related:  Occurs most commonly in abdominal aorta and common iliac arteries. ② Inflammatory:  Including IgG4-related disease. ③ Mycotic:  Occurs when circulating microorganisms (as from infective endocarditis) seed the aneurysm wall or associated thrombus. TYPES ④ Aortic dissection:  Hypertension is the major risk factor.  Most commonly, there is medial degenerative changes.  Inflammation is characteristically absent.  Blood enters the media from a tear in the intima or rupture of vasa vasorum.  It accumulates and splits the media into outer and inner layers forming aneurysm. Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins 2 Cerebral Aneurysms  Small and multiple.  Develop at the site of medial weakness at the bifurcation of cerebral arteries.  The most frequent cause of subarachnoid hemorrhage. CONGENITAL BERRY ANEURYSMS AT CIRCLE OF WILLIS INTRACEREBRAL  At region of basal ganglia, and may rupture leading to massive MICROANEURYSMS spontaneous haemorrhage. OF BENIGN HTN  Mycotic aneurysms. OTHERS  Atheromatous. ① Obstruction of vessels leading to ischemia. ② Pressure on surrounding structures. ③ Rupture leading to internal haemorrhage which may be fatal. ④ Thrombosis and organization, and may be embolization. Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins PHLEBOTHROMBOSIS THROMBOPHLEBITIS = DEEP VEIN THROMBOSIS (DVT) INFLAMMATION Present Absent COMMONLY-AFFECTED Superficial leg veins, arms Deep calf veins VEINS Prolonged immobilization causing MAIN CAUSE Vein injury or inflammation venous stasis & hypercoagulability Commonly silent. CLINICAL PRESENTATION Pain and signs of inflammation Fewer signs and symptoms Common, may be massive. EMBOLI Rare unless infective Sterile COMPLICATION Pulmonary embolism is rare Pulmonary embolism is common Both are characterized by the formation of a thrombus within veins. Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins DEFINITION Dilatation, elongation, thickening & tortuosity of veins. ① Superficial veins of the leg. COMMON SITES & ② Esophageal varices. TYPES ③ Hemorrhoids of rectum (piles). ④ Caput medusae (periumbilical veins). ① Congenital weakening of veins or valves. ② Increased venous pressure leading to stretching of the wall due to: a. Prolonged standing and straining of constipation. PATHOGENESIS b. Obstruction of venous return e.g. in cases of liver cirrhosis, bilharzial fibrosis, and pressure by pregnant uterus, enlarged prostate or cancer rectum. ① Venous congestion, edema and pain. ② Varicose ulcers: in the extremities, due to edema, ischemia and superimposed infection. COMPLICATIONS ③ Thrombosis and embolism: emboli are rare in theses superficial veins, in contrast to emboli from thrombosed deep veins. ④ Hemorrhage as in esophageal varices and hemorrhoids. VARICOSE VEINS ESOPHAGEAL VARICES HEMORRHOIDS VARICOSE ULCERS Dr. M. Shalaby pathology - CVS Aneurysms & diseases of veins  For the past 3 weeks, a 70-year-old woman has been bedridden while recovering from bacterial pneumonia. Physical examination now shows some swelling and tenderness of the right leg, which worsens when she raises or moves the leg.  Which of the following terms best describes the condition involving the patient's right leg? A. Lymphedema B. Disseminated intravascular coagulopathy C. Thrombophlebitis D. Thromboangiitis obliterans E. Varicose veins Answer: (C) Thrombophlebitis  It is a common problem that results from venous stasis. There is associated inflammation.  Lymphedema takes longer than 3 weeks to develop and is not caused by bed rest alone.  Disseminated intravascular coagulopathy more often results in hemorrhage, and edema is not the most prominent manifestation.  Thromboangiitis obliterans is a rare form of arteritis that results in pain and ulceration of extremities.  Varicose veins are superficial and can thrombose, but they are not related to bed rest. Dr. M. Shalaby