Heart Cardiac Cycle And ECG Flashcards
Function of the heart
-Part of the Cardiovascular system
-A physiological pump
• Contributes to overall pressure maintenance (total peripheral resistance, blood flow, heart rate, cardiac output
-Perfusion of orgrans (delivers and removes)
• What is the approximate cardiac output of a healthy 20 year old person?
~ 5 - 6 litres/min
Layers
Starting from the inside
-endocardium
-myocardium
-visceral layer
-pericardial cavity(space in between) filled with pericardial fluid ,ultra lean plasma which acts as a lubricant
-Parietal layer
Fibrous layer(attached to blood vessels and diaphragm sometimes )
Inside view of the heart
4 cardiac chambers
4 valves(made of fibrous tissue)
Tricuspid atrioventricular valve
Mitral atrioventricular valve
Pulmonarv semistinar valve(leads to Pulmonarv artery)
Aortic semi-lunar valve (leads to Aorta)
What does left ventricle generate
Highest pressure of all cardiac chambers
Sinoatrial node
-Spontaneously depolarising pacemaker
-Located in the Right Atrium at the junction of superior vena-cava)
-Responsible for atrial contraction
-Atrioventricular (AV) node
-In the right posterior portion of inter-atrial septum
-Oversees ventricular contraction
Right coronary artery
Supplies blood to
-righy ventricle
-right atrium
-Septum
-sa and av nodes
What does right coronary artery branch to
-right posterior descending artery
-marginal artery
Left main coronary
Supplies blood to
-left ventricle
-left atrium
What does left main coronary branch into
-circumflex artery(encircles the heart muscle,supplies the back and outer side of the heart )
-left anterior descending artery(supplies the front of the left side of the heart)
Myocardial cells
-branched
-striated
>lines visible through cells
>indicate the sarcomere edges
-mononucleated
>rich in mitochondria
Myofibril
Contains parallel myofilaments
Sarcomere
Contractile functional unit
Contains parallel myofilaments
Sarcolemma
Muscle cell membrane
Sarcoplasmic reticulum
Cells main calcium store
