Cardiovascular systems structures?
• The heart (pump) - right side to pulmonary circulation - left side to systemic circulation • Peripheral vascular system (Tubing) - Arteries carry oxygenated blood - Veins carry deoxygenated blood • Haematological system - Blood and components • Closely interlinked with lymphatic system
Function of cardiovascular system?
- Deliver oxygen, nutrients and other requirements to the cells
- Remove and transport waste, such as carbon dioxide to be excreted
The structures and function of the cardiovascular system, a diagram:
https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcSY5vl06CZhyb3qzrMixvzbShHFNWsq5cB4fJNMdB1QCuGqMFUO
Coronary arteries, a diagram:
https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcR3mld5ua-wbqpw64FAR_rhMAEFUVNZbrc-8RWjbloLujfWLNzk
Coronary Veins, a diagram:
https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcRyaDgigdedSxJiLH9g4Aq4jpdsk5tDWjOKOqvi4YDk5RNDYjA-
Layers of the heart wall from outer layer in:
- Pericardium
- Myocardium
- Endocardium
Structure/function of heart when systole or diastole, a diagram:
https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcTaMHH4XnspEft3Wc2CbdMkLOc6P1JjM61y0iHi7sUjCDLf4SZU
What are the Atrioventricular valves?
The connection/coordination between the arterial and ventricular chambers of the heart.
- Tricuspid valve
- Bicuspid valve
What are the Semilunar valves?
At basses of the aorta and the pulmonary artery, consisting of three cusps or flaps which prevent back flow.
- Pulmonary semilunar valve
- Aortic semilunar valve
What is the conduction system of the heart?
A group of specialised cardiac muscle cells in the walls of the heart that send signals to the heart muscle causing it to contract.
- Sinoatrial node (SA)
- Atrioventricular node (AV)
- Bundle of His (AV bundle)
- Right and left bundle branches
- Purkinji fibres
What is cardiac output?
The amount of blood pumped into the ventricles into the pulmonary and systemic circulations in 1 minute.
• Preload
- left ventricular end diastolic volume
- frank-starling law of the heart
• Afterload
- resistance that must be overcome for blood to be ejected.
• Contractility
What is strike volume?
The amount of blood pumped into the aorta with each contraction of the left ventricle.
What is ejection fraction?
The percentage of total blood remaining in the ventricle at the end of diastole (relaxation); normal is 50-70%
The peripheral vascular system:
- Arteries
- Arterioles
- Capillaries
- Venules
- Veins
- and repeat
Structure of an artery and vein, a diagram:
https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcTRph3x5_RYxlTKRiQoePEvz9Ahd4Qu1P4B5WjSMSepZpTYQSgs
Blood flow, a diagram
https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcSwadEeXG7wg0OoY71g-mA_Q3ZyxruA1p7TpDJ5Q2Lnp5ci8ZZt
Peripheral vascular resistance (PVR), or blood flow resistance:
Determined by three factors:
•Blood viscosity- thickness of the blood
•Length of vessel- ^length ^ resist
•Diameter of vessel- smaller the diameter the greater resistance
What is an Arrhythmia disorder?
- Generation of an electrical impulse produces a coordinated and synchronised muscle contraction through the myocardium that pumps blood into the pulmonary and body systems. With this condition this coordinated and synchronised action may be affected.
- a disturbance or irregularity in the electrical system of the heart
- Arrhythmias can be minor (benign) or life threatening.
- Classified according to; site of abnormal impulse generation, and degree of block impulse.
What two Pathophysiological causes Arrhythmia (conduction disorders?
- Abnormal impulse generation- SA and AV node
* Abnormal impulse conduction (heart block)- myocardial cell disorders
What non pathophysiological causes Arrhythmia?
- Fear
- Excitement
- exercise
- Hyperthermia
What are the effects of Arrhythmia?
- rate
- rhythm
- combination of the above
- potentially alter blood flow/cause haemodynamic changes
What is Supraventricular Arrhythmia?
• Can be ‘normal’, often minimal intervention required • Generated in SA node/within atria • Often has a P and T wave/normal QRS - sinus rhythm - sinus Arrhythmia - sinus tachy and bradycardia - atrial fibrillation
What is Ventricular Arrhythmia?
• Much more serious
• Does not usually activate SA node or Atria
• QRS complexes peculiar indicating minimal useful ventricular output
- ventricular tachycardia
- ventricular fibrillation
What is Atrioventricular conduction block Arrhythmia?
•interruption ‘blocks’ of the impulse travelling from atria to ventricles •minor affect •major, immediate treatment required - first degree AV block - second degree various AV blocks - third degree AV block
