Lecture 29 - Obesity I

Question 1

What is obesity?

Answer 1

Excess accumulation of body fat

Question 2

What are risk determinants of metabolic syndrome?

Answer 2

Adiposity
Lipid profile
Blood pressure
Blood glucose

Question 3

What mechanisms contribute to cardiac dysfunction in obesity?

Answer 3

1. Hemodynamic load (volume expansion)
2. Heart fat - conduction system
3. Adipocytes - Adipokines - myocardial fibrosis
4. Microangiopathy - endothelial dysfunction

Question 4

What is the hemodynamic load in obesity?

Answer 4

Increased mass result in increase in overall body blood flow (more tissue to perfuse with blood)
- increase in CO and preload
- decrease in TPR

Question 5

What is primary cardiac remodelling in obesity?

Answer 5

Cause: Volume overload
LA and LV eccentric hypertrophy

Question 6

What is secondary cardiac remodelling in obesity?

Answer 6

Cause: Pressure overload
LV concentric hypertrophy

Question 7

What is effected in the deposition and infiltration of heart fat?

Answer 7

• Mechanical impairment
• Thermoregulation (higher body core temperature)
• Cardiac conduction
• Endocrine effects (adipokines, cytokines)

Question 8

What is the effect of heart fat in the conduction system?

Answer 8

LV and RV hypertrophy
eccentric and concentric remodeling
Fatty infiltration in conduction system
Prolongation of QT interval
Adipokines, cytokines release
Sleep apnea - cardiac arrhythmias - sudden death

Question 9

What are the effects of adipose on vascular regulation?

Answer 9

Changes balance between vasoconstriction and vasodilation
Microangiopathy - Retinopathy - Nephropathy - Neuropathy