Ex3 L13 Cardiovascular

Question 1

Cardiovascular disease includes…

Answer 1

coronary artery disease, myocardial infarction, heart failure, stroke, cardiomyopathy, etc.

Question 2

Describe the statistics on CVDs

Answer 2

• leading cause of death for people over 65
• approximately 25% of deaths
• coronary heart disease (CHD) accounts for half of CVD deaths

Question 3

What is the greatest unmodifiable risk factor for CVD?

Answer 3

age

Question 4

Rates of CVD are lower in women…

Answer 4

before menopause, because estrogen is cardioprotective

Question 5

In an aged heart, we see gross changes such as…

Answer 5

• left ventricular hypertrophy
• diminished cardiac reserve
• degeneration of valves (especially mitral valve)
• cardiac fibrosis

Question 6

In an aged heart, we see changes in cardiomyocytes such as…

Answer 6

• larger and flatter
• growth arrest/senescence/SASP expression
• telomere shortening

Question 7

Loss of pacemaker cells with age causes…

Answer 7

decreased heart rate

Question 8

What is atherosclerosis?

Answer 8

disease characterized by deposition of plaques on artery walls

Question 9

Vascular aging causes…

Answer 9

• inflammation of arterial vessel walls
• stiffening and narrowing of arteries with age
• creates higher risk for blockage (and therefore stroke or myocardial infarction)

Question 10

What role does stress play in cardiovascular disease?

Answer 10

• stress, anger, and depression can trigger cardiac events
• social isolation (by 1.5x)
• stress in the workplace (by 1.3x)
• stress worsens prognosis for existing CVD

Question 11

How does fat distribution change with age and effect CVD?

Answer 11

• estrogen favors gynoid fat distribution (pear)
• cortisol favors android fat distribution (apple)
• loss of estrogen at menopause shifts fat distribution
• android has a higher risk for CVD and hypertension

Question 12

How does blood pressure change with age?

Answer 12

• continual increase is systolic after age 30
• diastolic decreases after age 50 (increases pulse pressure due to large artery stiffness)

Question 13

How does hypertension change with age?

Answer 13

systolic hypertension is most prevalent in ages 50+, most treatable risk factor for CVD, and treatment reduces risk of cardiac events in elderly people

Question 14

What other cardiovascular changes occur with age?

Answer 14

• Decreased sensitivity of baroreceptors
• Increased responsiveness to SNS stimuli
• Altered renin-angiotensin-aldosterone system

Question 15

How does stroke risk change with age?

Answer 15

• Every 45 seconds, someone in the US has a stroke
• Risk of stroke doubles every 10 years after age 55
• Strokes occur more frequently and are more severe in older people
• Death rate from stroke increases with age

Question 16

What is the neurovascular unit?

Answer 16

• A group of cells that regulates interactions between brain tissue and
  cerebral vasculature
• Includes neurons, astrocytes, pericytes, microglia, epithelial cells, and vascular smooth muscle cells

Question 17

What is the blood brain barrier?

Answer 17

• part of the neurovascular unit
• separates blood from CSF
• consists primarily of endothelial cells, pericytes, and astrocytes

Question 18

How does the neurovascular unit change with age?

Answer 18

• decrease pericyte function (impaired regulation of blood flow, leaky BBB)
• microglia increase in number but function changes
• endothelial cells have reduced NO production and impaired vasodilation (ROS react with NO to make peroxynitrate, which damages neurons)
• all contribute to risk of ischemic stroke

Question 19

How do the microglia change with age?

Answer 19

• increase in number but have altered function
• swtich from M2 healing to M1 inflammatory
• the more “hits” the brain experiences, the more microglia become M1 and cause neurodegeneration/inflammation and accelerating aging

Question 20

How does the hormetic zone apply to the neurovascular unit?

Answer 20

• some inflammation and activity of microglia is necessary
• but too much (especially if it is dysregulated) can be detrimental