Heart
💖 UNIT: HEART (Anatomy) Cardiovascular System – BSc Nursing 1. Definition The heart is a hollow, muscular organ that acts as a pump to circulate blood throughout the body. 2. Location Situated in the middle mediastinum of the thorax Between the two lungs Immediately above the diaphragm Lies behind the sternum and adjoining costal cartilages Mostly to the left of the midline 3. Size and Weight Size: Slightly larger than a clenched fist Average Weight: Male: ~300 g Female: ~250 g 4. Coverings and Wall Layers of the Heart The heart wall consists of three layers : Epicardium Outermost layer Protective covering Myocardium Middle and thickest layer Composed of cardiac muscle Responsible for pumping action Endocardium Innermost layer Lines the chambers and valves 5. Anatomical Position of the Heart Apex Directed downward, forward, and to the left Located in the 5th intercostal space Just medial to the mid-clavicular line Appro...