Anatomy Lab Heart Anatomy

Heart location

Medial chest cavity between lungs, slightly left

Function of the heart

Pumps blood through the body

Number of heart chambers

4

Atria

Receiving chambers (low pressure)

Ventricles

Discharging chambers

Septum

Divides heart into left and right sides

AV valves

Prevent backflow into atria

Types of AV valves

Bicuspid (mitral) and tricuspid

Chordae tendineae

Anchor valves to papillary muscles

Semilunar valves

Prevent backflow into ventricles

Types of semilunar valves

Pulmonary and aortic

Coronary circulation

Blood supply to heart muscle

Anterior interventricular artery

Supplies front of heart

Posterior interventricular artery

Supplies back of heart

Right coronary artery

Supplies right side of heart

Left coronary artery

Supplies left side of heart

Marginal artery

Supplies lateral heart wall

Circumflex artery

Wraps around heart (branch of left coronary)

Great cardiac vein

Drains anterior heart

Middle cardiac vein

Drains posterior heart

Anterior cardiac vein

Drains right ventricle

Small cardiac vein

Drains right side of heart

Coronary sinus

Collects blood from cardiac veins

Heart sounds (lub-dub)

Sound of valves closing

Lub

AV valves close (start of systole)

Dub

Semilunar valves close (start of diastole)

Cardiac cycle

One complete heartbeat

Systole

Heart contraction

Diastole

Heart relaxation

ECG/EKG

Records electrical activity of heart

P wave

Atrial depolarization

QRS complex

Ventricular depolarization

T wave

Ventricular repolarization

SA node

Pacemaker of heart

AV node

Delays signal before ventricles contract