Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Management of acute coronary syndrome wikipedia , lookup
Quantium Medical Cardiac Output wikipedia , lookup
Antihypertensive drug wikipedia , lookup
Cardiac surgery wikipedia , lookup
Coronary artery disease wikipedia , lookup
Myocardial infarction wikipedia , lookup
Dextro-Transposition of the great arteries wikipedia , lookup
HISTOLOGY OF CVS PROF. DR. FAUZIAH OTHMAN DEPT OF HUMAN ANATOMY CONTENT Histological features of cardiac muscles, epicardium, endocardium, Histological features of the Purkinje fibres. Histological features of the elastic artery, muscular artery and arteriole Histological features of the large and medium vein, venule. Histological features of capillaries. Cardiac muscle Striated Involuntary single, centrally placed nucleus COVERING OF THE HEART Pericardium The membrane surrounds to protects heart. Consist 2 principal portions: • fibrous pericardium • Serous pericardium Fibrous Pericardium Serous pericardium •Superficial •Tough •Inelastic •Dense irregular connective tissue •Deeper •Thinner •More delicate membrane that form double layer round the heart Fx: prevent overstretching of heart, provide protection & anchor of the heart to mediastinum. •Outer parietal of serous pericardium –fused to fibrous pericardium Visceral layer of serous pericardium--epicardium HEART WALL 1. 2. 3. Heart comprises of three layers; Epicardium( external layer) Myocardium ( middle layer) Endocardium (inner layer) Epicardium (epi= on top of) Visceral layer of the serous pericardium Thin, transparent outer layer of the wall Composed mesothelium & CT Myocardium (myo = muscle) Composed cardiac muscle tissue Responsible for pumping action. Stratified, involuntary & intercalating bundles Endocardium (endo= within) thin layer of endometrium Smooth muscle The outmost layer is composed of irregularly arranged collagen fibres that merge with collagen surrounding adjacent cardiac muscle fibres. This layer may contain some Purkinje fibres, which are part of the impulse conducting system . PURKINJE FIBERS (OR PURKYNE TISSUE) are located in the inner ventricular walls of the heart, just beneath the endocardium. These fibers are specialized myocardial fibers that conduct an electrical stimulus or impulse that enables the heart to contract in a coordinated fashion. PURKINJE FIBERS SPECIALIZED CARDIAC MUSCLE FIBERS Heart: contracting cardiac muscle fibers and impulse-conducting Purkinje fibers. Stain: Mallory-azan 5 MAIN TYPES OF BLOOD VESSELS 1. 2. 3. 4. 5. Arteries (ar= air; ter= to carry) Arterioles Capillaries Venules Veins TYPE OF ARTERIES There are 3 types of arteries Elastic arteries Muscular arteries Arterioles The luminal diameter of artery gradually decrease with each branching. ARTERY Wall have 3 tunics: Tunica interna (intima) Tunica media Tunica externa Tunica interna (intima) composed simple squamous epithelium (endothelium) & layer elastic tissue (internal elastic lamina) Closest to lumen Tunica media Thickest layer Elastic fiber & smooth muscle fibers arranged in ring around lumen Tunica Externa Composed principally of elastic & collagen fibers Elastic arteries/ conducting arteries Muscular arteries/ distributing arteries Largest blood vessel in the body Larger-diameter Tunica media contain high proportion of elastic fiber Most numerous vessels in the body. Medium size Tunica media contain high proportion of smooth muscle fiber Eg: brachial artery or popliteal artery Eg: aorta & pulmonary trunk ARTERIOLE (= SMALL ARTERY) The smallest branches of arterial system. The wall of arteriole consist of one to five layers of smooth muscle fibers. Arteriole deliver blood to the capillaries, which are microscopic blood vessels that connect arteriole with the venules. DIFERRENCES BETWEEN ARTERY & VEIN Artery Vein •Thick and elastic muscular walls •No valves •carriers of oxygenated blood (exception: pulmonary arteries which carry de-oxygenated blood from the heart to the lungs). •Thin and slightly muscular walls. •internal valves (to prevent back flow of blood) •veins carry de-oxygenated blood (exception: pulmonary veins which carry oxygenated blood from the lungs to the heart) Artery and vein in connective tissue of the vas deferens. Stain: iron hematoxylin and alcian blue Muscular artery and vein (transverse section). Stain: elastic stain Blood and Lymphatic vessels stain with H&E Wall of large vein: portal vein(tranverse section). Stain:H&E Heart: right ventricle, pulmonary trunk, and pulmonary valve. Stain: H&E CAPILLARIES Microscopic vessel that connect arteriole to venule. Capillary wall composed of ONLY a single layer of endothelial cell & a basement membrane. NO tunica media & NO tunica externa Perculiar- protuding nucleus in the lumen. Type of Capillaries. Continuous Fenestrated Discontinuous/ Sinusoidal Plasma membrane of endothelial cells form are continuous tube Plasma membrane of endothelial cells have many small pores, ranging from 70-100nm in diameter Wider & more winding than other capillaries Found in skeletal muscle, central nervous system, skin, gonads, connective tissue and lungs Found in endocrine glands, intestines, pancreas and glomeruli of kidney Large pores Primarily located in the liver, spleen, bone marrow, lymph nodes, and adrenal cortex. VASA VASORUM network of small blood vessels that supply large blood vessels. This is because: The wall of larger arteries and vein are too thick to receives nourishment direct diffusion from their lumina . VENULES Several capillaries form small vein The smallest venules, those closest to the capillaries, consist of a tunica interna of endothelium & tunica media that has only a few scattered smooth muscle fiber & fibroblast. VEINS Same as tunica in arteries BUT different in thickness. Tunica interna more thinner (little SM & elastic fiber) Tunica externa of veins is thickest layer (collagen & elastic fibers) Vena cava- longitudinal fiber of smooth muscle. Veins LACK external or internal elastic lamina found in arteries CLINICAL CORRELATION Congestive heart failure occurs when the heart is unable to adequately pump blood. Because of this the body's tissues don't receive enough blood to function properly. Congestive heart failure can be a devastating disease for both dogs and cats, striking primarily older and obese animals