Question

CONTENT CHECKLIST oDescribe at least one organ or organ system. Use at least 1 directional term. oUse at least on regional term Use at least one suffix (such as-itis,-scopy etc.) and define it in the report

Answer 1

HEART

• Roughly cone shaped hollow muscular organ it's about 10cm long and is about the size of owners fist, it weighs about 225g in women and 310g in men

Position

• Heart lies in the thoracic cavity in the midiastinum (space between the lungs)
• It lies obliquely a little more to the left than the right ,and a base above and apex below
• Apex is about 9cm to the left of the midline at the level of the 5th intercostal space, a little below the nipple and slightly nearer the midline
• The base extends to the level of 2 nd rib
• Inferiorly:=apex rest on central tendon of diaphragm
• Superiorly :=aorta ,superior venacava ,pulmonary artery and pulmonary veins
• Posteriorly :=oesophagus ,trachea ,left and right bronchus ,descending aorta, inferior Vena cava and thoracic vertebrae
• Laterally :=lungs, left lung overlaps left side of the heart
• Anteriorly :=sternum ,ribs and intercostal muscles

Structure

• Heart composed of three layers of tissues pericardium, myocardium ,endocardium
• Pericardium :=
• made up of two sacs outer sac fibrous tissue inner double layer of serous membrane
• Outer sac consist of tunica adventitia of great blood vessels above and adherent to diaphragm below
• Double layer of serous membrane is the perital pericardium ,visceral pericardium or epicardium
• Serous membrane consist of flattened epithelial cells.it secretes serous fluid into space between visceral and parietal layers which allows smooth movement between them when the heart beats
• Mayocardium :=
• It composed of specialised cardiac muscle found only in the heart
• The mayocardium is thickest at the apex and thins out towards the base ,it thickness in left ventricle which has great work load
• Endocardium :=
• Lines the chamber of heart and valves,it is smooth ,thin, glistening membrane promote smooth flow of blood in side the heart

Interior of heart

• Heart is divided in to four chambers right atrium ,left atrium ,right ventricle ,left ventricle right and left chambers devided by septum ,atrium and ventricle is devided by atrioventricular valve
• Atrioventricular valves formed by double folds of endocardium strengthened by a little fibrous tissue
• Right atrioventricular valve know as tricuspid valve which has three cusps ,left is known as mitral valve which has two cusps
• Valves open and closes passively according to change in pressure in the chambers
• Right atrium has the opening of superior and inferior Vena cavalier and right ventricle has opening of pulmonary artery which composed of pulmonary valve
• Left atrium has openings of pulmonary veins and left ventricle has opening of aorta which composed of aortic valve
• Heart is supplied with arterial blood by right and left coronary arteries which branches from aorta immediately distal to the aortic valve, venous drainage is by small veins join to form coronary sinus
• Heart is intrinsic system. Cardiac muscle automatically stimulated to contract without the need for external stimulation by small group of neuromuscular cells in mayocardium which comprises of sinoatrial node, atrioventricular node, av bundle or bundle of his right and left bundle branches and purkinje fibres

​​​​​​​Diseases of heart

Infective endocarditis

• Pathogenic organism bacteria or fungai may colonise any part of endocardium most common site is near the valves port of entry of organisms include oral cavity ,cutaneous invasion ,surgery
• Symptoms :=
• fever, anorexia ,weight loss, fatigue ,cardiac murmurs,heart failure ,petechiae ,splenomegaly
• Intervention :=
• provide adequate rest
• Maintain antiembolism stockings
• Monitor cardiovascular status
• Monitor signs of emboli
• Monitor for splenic emboli
• Monitor for confusion ,aphasia which may indicate central nervous system emboli
• Evaluate blood cultures
• Administer antibiotics intravenously as prescribed