Metabolic Disease of the Heart

Question 1

What effects do hyperthyroidism have on the heart?

Answer 1

Direct inotropic (contractility) and chronotropic (HR) effects;

1. Increase activity of the sarcolemmal sodium pump
2. enhances synthesis of myosin isoform with rapid ATPase activity and reduces production of slower isoform
3. upregulates expression of slow calcium channels in sarcolemma thereby facilitating contractility

Conspicuous tachycardia and increased cardiac workload

Question 2

What is myxedema? What does it cause?

Answer 2

Severe hypothyroidism; Decreased cardiac output, reduced HR, impaired contractility

Question 3

What are the effects of Thiamine Deficiency on the heart? What condition is this similar to? What do patients die from with this deficiencey?

Answer 3

1. Decreased peripheral vascular resistance
2. Increased cardiac output

Hyperthyroid; High output heart failure

Question 4

What is another name for thiamine?

Answer 4

B1