HEART REVIEWER FROM MAAM

• Heart - muscular pump
• Arteries - which carry blood from the heart

  to the tissues
• Veins - which return blood from the tissues to the heart
• Capillaries - which intervene between the blood and other tissues
• two atria- thinner-walled chambers located at the base (top) of the heart
• TWO VENTRICLE - - thicker-walled chambers located in the

  body and apex of the heart
• HEART is Four-chambered, hollow, muscular organ lying between

  the lungs in the middle mediastinum
• Size of a man’s fist hand, and in the normal male weighs

  approximately 250-300gm/200-275gm.
• Shape: like an inverted cone, with its apex pointed

  downward and to the left base upwards and to the right
• • its apex anteriorly and inferiorly to the left at 5th ICS,MCL
• PERICARDIUM - is an invaginated sac consisting of
• Fibrous pericardium - tough covering which provide protection and anchors the heart into mediastinum
• Visceral pericardium: immediately covers the heart
• Parietal pericardium: covers the pericardial cavity
• 2 Atria: receiving chamber
• 2 Ventricle: discharging chamber
• Atrioventricular valves:

  1. Tricuspid valve: RA - RV
  2. Mitral/Bicuspid valve: LA - LV
• Semilunar valves

  1. Aortic valve : LV - Aorta
  2. Pulmonic valve: RV – Pulmonary artery
• trabeculae carneae -irregular muscular ridges probably to hold more blood.
• papillary muscle- conical in shape with the base attached to

  the ventricular wall and the apices receiving the end of chordae tendinae
• chordae tendineae- thread-like structures connected to the apices of the papillary muscles and to the cusps of ventricular valves.
• Coronary arteries- blood supply of the heart
• RIGHT ATRIUM

  receives venous blood from:

  1. superior vena cava
  2. inferior vena cava
  3. anterior cardiac veins
  4. the coronary sinus
• RIGHT ATRIUM larger than left atrium
• RIGHT VENTRICLE - Receiving venous blood from right atrium and

  ejecting this to the pulmonary arteries
• RIGHT VENTRICLE thinner walled than left ventricle
• LEFT ATRIUM - quadrilateral in shape and its interior shows

  the openings of the four pulmonary veins from

  the lungs.
• blood leaves the left atrium and enters the left ventricle via the left atrioventricular orifice or mitral orifice.
• LEFT VENTRICLE (apex of heart)
• LEFT ATRIUM ( base of the heart)
• left ventricle cavity is longer and the walls are 3x thicker

  than right ventricle
• parasympathetic Decrease HR
• sympathetic Increase HR
• Sinu-atrial node (Pacemaker of the heart)
• Sino-atrial node- located at the posterior wall in the groove between the superior vena cava and the right atrium
• Atrio-ventricular node -located at the lower part of the interatrial septum
• S1- first heart sound closure of the AV valves
• S2- closure of the semilunar valves
• S3- ventricular gallop
• S4- atrial gallop