What are Bruits?
The sound of turbulent flow in an artery heard with a stethoscope
What are the 3 main mechanisms of cell injury caused by hypoxia/ischaemia?
- Decreased levels of ATP
- Membrane damage
- Increased intracellular calcium
What are the complications of an MI?
- Sudden death
- Cardiac arrhythmias
- Left ventricular failure
- Ventricular wall rupture
- Papillary muscle fibrosis/rupture
- Mural thrombus
- Ventricular aneurysm
What are the major and constitutional risk factors of atherosclerosis?
- Family history
What causes a fluid's viscosity?
The layers of fluid interacting with one another rather than slipping past each other
What are the effects of Angiotensin II and ADH on the vascular system?
They are both powerful vasoconstrictors
What generally is autoregulation of blood flow?
Regardless of large changes in perfusion pressure the blood flow remains relatively constant
What is hypoxia?
A lack of oxygen resulting in a decrease in aerobic respiration resulting in cell injury
What is found in the lipid cores of an atheromatous plaque?
- Cellular debris
- Cholesterol crystals
- Foam cells
What is infarction?
Irreversible cell damage (death) due to ischaemia and hypoxia
What is ischaemia?
A lack of blood supply from a stenotic/occluded artery or reduced venous drainage that causes cell injury more rapidly that hypoxia.
What is plug flow (bolus flow)?
It is the phenomenon whereby RBCs travel single file in the capillaries
What is the Fahraeus-Lindqvist effect?
It is the phenomenon whereby the effective viscosity of a fluid decreases considerably with decreasing tube radius when it flows through a tube less than 100 μm
What is the fibrous cap of an atheromatous plaque made of?
- Smooth muscle
- Proteoglycan rich stroma
What is the flow of turbulent fluid proportional to?
The square root of the pressure gradient
What is the main receptor that the sympathetic nervous system exerts its effect on the vascular system?
What is the initial management of acute coronary syndrome?
- Nitrates - Sublingual TGN
What is the secondary management plan for ACS?
- ACE inhibitor (Ramipril)
- Beta-blocker (Bisoprolol)
- Statin (Simvastatin or Atorvastatin)
What is the velocity profile of laminar flow within a blood vessel?
What type of flow is the Poiseulle equation used to describe?
What variable affects resistance the most within a blood vessel?
The radius of the vessel
When do RBCs form rouleaux, and what are rouleaux?
They are where the RBCs form a column within the blood.It occurs when the blood velocity is slow
Where is the fastest movement within a blood vessel?
In the centre of the vessel
Which organs are susceptible to ischaemia-reperfusion injury?
- Skin - distal extremities
Which organs exhibit autoregulation of blood flow?