3.7

Question 1

What is the relationship between atrial pressure and ventricular output

Answer 1

As atrial pressure increases, ventricular output increases up to a threshold (sigmoidal)

Question 2

Summarise the arterial baroreflex

Answer 2

Low blood pressure -> high HR
High blood pressure -> low HR

Question 3

Describe intrinsic cardiovascular regulation

Answer 3

• Frank starling -> increased venous return leads to increased cardiac output
• Atrial pressure is proportional to ventricular output

Question 4

Describe extrinsic cardiovascular regulation

Answer 4

• Nervous: Parasympathetic decrease HR and modestly reduces contractility, and sympathetic increases HR and increases contractility
• Endocrine: adrenaline and noradrenaline released due to sympathetic inervation of adrenal medulla, increased HR and contractility, and vasoconstriction