Question 9

Describe the changes to cardiovascular physiology in a healthy elderly person.

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College Answer

It is clearly stipulated in the syllabus that candidates would be expected to understand 
physiology as it applies at the extremes of age. In the past, questions have been asked 
relating to foetal and neonatal physiology as well as for the elderly. This question was poorly 
answered as candidates lacked a detailed and coherent knowledge of this topic. For a good 
answer candidates were expected to at least mention the effects on the heart, e.g. increases 
in size due to concentric ventricular hypertrophy (LVH), hypertrophy of myocytes but a 
decrease in the number of myocytes, cardiac output decreases, the increase in cardiac 
output in response to severe exertion is attenuated, ventricular filling is particularly 
dependent on diastolic relaxation which is impaired, greater contribution of atrial 
contraction, increase in left ventricular afterload, effects on vasculature, e.g. intima and 
media thickening result in less distensibility, effects on endothelial function, e.g. nitric oxide 
release is decreased, effects upon autonomic and integrated responses, e.g. decline in 
receptor numbers, down regulation of post-receptor signalling and decreased receptor 
density and impaired baroreceptor reflexes.