Chapter 25 Circulatory System Blood -Vascular

Two Systems of Circulatory System Both carry oxygen and nutrients to tissues in continuous, endless uni-direction Both transport waste products to organs of excretion Skin Lungs Liver kidneys

2 Circulatory Systems cont’d Blood-Vascular System- major portion- transports blood Lymphatic System- minor portion - collects fluid from tissue spaces, filters through lymph system

Bloodvascular System Lymphatic System

Blood-Vascular System Heart has 2 circulation routes Systemic Pulmonary Both carry oxygenated blood to organs and tissues

Pulmonary, systemic, and portal circulation red = oxygenated blue = deoxygenated purple -nutrient-rich

Systemic Circulation Pumps blood to organs

Pulmonary Circulation Takes returning blood to lungs to exchange carbon dioxide for oxygen Carries oxygenated blood from lungs to heart Only veins in post-fetal human body carrying oxygenated (red) blood

Portal System Pathway of venous drainage from abdominal organs through liver before returning to inferior vena cava Liver has 2 blood supplies!

Anatomy: Heart 4chambers – Myocardium - muscular wall of heart 2 atria- upper, receiving chambers 2 ventricles- lower, distributing chambers Myocardium - muscular wall of heart Endocardium - inner lining of heart Epicardium - thin membrane that covers heart Pericardial sac double-walled outermost covering of heart

Heart Valves Right atrioventricular (AV) valve or tricuspid valve controls opening between right atrium and ventricle Left AV valve or mitral valve controls opening between left atrium and ventricle

Great Vessels of Heart Deoxygenated/Oxygenated Blood Flow Pulmonary artery Aorta Vena Cava Inferior and Superior portions Pulmonary Vein

Anatomy: Heart Right side of heart- handles venous, or deoxygenated blood Left side of heart- handles arterial, or oxygenated blood

Coronary arteries supply blood to myocardium (muscular wall of heart) Right Coronary artery Left Coronary artery Coronary sinus Great cardiac vein

Myocardial infarction (MI) Commonly known as a heart attack interruption of blood supply to part of heart, causing some heart cells to die Most commonly due to occlusion (blockage) of a coronary artery

CABG (Coronary Artery Bypass Graft) Surgery called revascularization to improve blood flow to heart in people with severe coronary artery disease (CAD) Occurs coronary arteries become blocked due to buildup (plaque) on inside of blood vessels. If severe, chest pain (angina), shortness of breath, possible heartattack and death healthy artery or vein grafted, to blocked artery bypassing blocked portion New passage routes oxygen-rich blood around the blockage to heart muscle Up to 4 major blocked coronary arteries can be bypassed during 1 surgery. Collateral veins will take over role previously performed by piece removed.

Blood -Vascular System Radiological Studies Slide 17

Various Radiologic Studies Angiography - exam of vascular structures - contrast medium Arteriography - exam of arteries -contrast injection Venography - of veins - contrast injection

Indications Claudication - leg pain and cramping Stenosis - narrowing of vessel Occlusion -blockage of a vessel Aneurysm -weakened area of artery “ballooned” Suspected tumors Anatomic variances

Contrast dye is injected Automatic injector is most commonly used Manual injection is done rarely Injectors are programmed to coincide with imaging sequence Rapid film changers are rarely seen

Equipment Digital equipment Digital subtraction -instantly “subtracts” overlying bony structures better visualization of contrast-filled vascular structures Cinefluorography still used in cardiac catheterization procedures

Equipment

Catheterization Catheter - small, flexible tube inserted into vessel through which contrast is introduced Femoral artery most common introduction site Radial Brachial Axillary Jugular Subclavian

Femoral Catheter Introduction

Complications! Bleeding at puncture site Allergic reaction to contrast Nerve, vessel, or tissue damage Stroke Heart attack Death

Angiographic Team Physician – usually an interventional radiologist CIT -cardiovascular-interventional technologist Anesthetist, nurse, etc

Procedures Aortography Pulmonary arteriography Thoracic Abdominal Pulmonary arteriography Abdominal visceral arteriography

Thoracic Aortography Rule out aortic aneurysm Evaluate congenital or postsurgical conditions Evaluate aortic dissection Biplane imaging - PA and lateral obtained with one contrast injection

Abdominal Aortography To Detect Abdominal aortic aneurysm Occlusion Atherosclerotic disease

Cerebral Angiography

Cerebral Angiography To investigate: Aneurysms AVM (Arteriovenous malformation) Tumors Atherosclerosis Stenosis

Arteriogram of Hand

Circle of Willis Arrangement of brain's arteries creating redundancies in cerebral circulation If one part of circle becomes blocked or narrowed blood flow -other blood vessels can often preserve cerebral perfusion well enough to avoid loss of blood supply (ischemia) The

Interventional Radiology

Balloon Angioplasty Used to dilate strictures in venous structures, ureters, and GI tract

Inferior Vena Cava Filter Trap emboli to prevent pulmonary embolism resulting from deep vein thrombosis of lower limbs Delivered via a catheter - assume functional shape as released

Vena Cava Filter

Foreign object removal Stones and other occlusive objects can be retrieved via a special catheter with snare at the end

Cardiac Catheterization Minor surgical procedure involving introduction of special catheters into heart, great vessels, and coronary arteries

Catheter placement in heart

Specialized Equipment

Specialized Equipment

Venography

Indications For Venography Deep vein thrombosis: Formation of blood clot inside blood vessel When blood vessel injured body forms blood clot to prevent loss of blood If too much clotting & clot breaks free travels in bloodstream – blocks blood vessel - obstructs circulation (embolism) If goes to lungs - can rupture pulmonary artery, causing death

Other Indications for Venography Venous obstruction Recurrent varicose veins Swollen legs of unknown etiology Varicose ulcers Venous malformations

Central Venography 2 studies Superior venacavogram Inferior venacavogram Purpose Rule out existence of thrombus or occlusion of central veins

Central Venography Superior venacavogram performed by accessing axillary or subclavian vein Inferior venacavogram performed by accessing femoral vein and placing catheter in common iliac vein or inferior aspect of inferior vena cava

Peripheral Venography Examines superficial and deep veins of extremities Less common today-replaced by advances in ultrasound

Anatomy Superficial veins Deep veins Dorsal venous arch Small saphenous vein Great saphenous vein Deep veins Anterior tibial Posterior tibial Peroneal Popliteal External iliac Internal iliac Femoral vein

Procedure Patient is supine on table Injection area cleansed IV started in dorsum of foot or hand Tourniquets applied Injection started Radiographs obtained

Indications For Upper Limb Venography Edema of arm or hand Venous obstruction Suspected thrombosis

Lower-Limb Venogram AP of entire extremity Lateral of entire extremity

The End