13. Regulation Of BP And Hypertensive Vascular Disease

Question 1

Blood Pressure

Answer 1

Cardiac output- determined by myocardium contractibility, HR and blood volume

Peripheral resistance - humoral and neural factors

Question 2

Atrial natriurtic peptide (ANP0

Answer 2

Released from heart in response to blood volume increase

Vasodilation and sodium excretion

Lower BP

Question 3

Renin

Answer 3

Released from kidneys in settings of hypotension

Converts angiotenisgon - angiotengion I which is converted to angiotensin II in lungs

Angiotensin II - vasoconstrictor increase BP,
alderosterone production =increase renal sodium reabsorption (increase BP)

Question 4

BP classifications

Answer 4

Normal less then 120 less then 80

Elevated 120-129. Less than 80

High blood pressure HT stage 1 - 130-139. 80-89

HT stage 2. 140 or above. 90 or above

Stage 3. Higher then 180. Higher then 120

Question 5

Essential hypertension

Answer 5

Accounts for 90-95% of cases

Question 6

Secondary hypertension

Answer 6

Renal - chronic renal disease (renin-angiotenisngin-aldosertone syndrom3e)

Endocrine - Cushing’s

Cardiovascular

Neurological - acute stress

Question 7

Mechanisms of essential hypertension

Answer 7

90% idiopathic - unknown

Reduced renal sodium excretion = increase fluid volume, increase cardiac output, increase BP

Increase vascular resistance - vasoconstriction/ structural changes

Genetic factors

Environmental factors - salty diet, smoking, stress

Question 8

Aneurysms

Answer 8

Abornomal vascular dilation

Question 9

Types of anyerisms

Answer 9

True - bounded by all three vessel wall layers

False- extravascular hematoma that communicates intramuscular space, collection of blood and CT outside aortic wall, part of vessel wall has been lost

Dissection - blood enters atrial wall it’s self, tear in intima

Question 10

Pathogenesis of anyerisms

Answer 10

1. Inflammation
2. Inadequate degredation of ECM
3. Apoptosis of SMC due to ischemia

Question 11

Aortic aneurysm

Answer 11

Most common cause is atherosclerosis

Weak spot in wall of aorta beings to bulge

Question 12

Abdominal aortic aneurysms (AAA)

Answer 12

Etiology - true aneurysms, atherosclerosis

Pathogenesis is - inflammatory filtrate in atheroscletic lesion produce proteoletic enzymes-that degrade ECM

Clinical features: asymptomatic
Ruptures into peritoneal cavity with massive hemhorrahe
Occlusion of branch vessel
Athero-embolism

Question 13

Thoracic aortic anyerisms

Answer 13

Compression of adjacent structures

Etiology - hypertension

Clinical features:

Respitory/ feeding difficulties 
Persistent cough
Pain
Cardiac abnormalities
Aortic dissection/rupture

Question 14

Aortic dissection

Answer 14

Blood dissects the media and enters aortic wall forming blood filled channel

Major clinical consequence

Often leads to rupture causing sudden death through massive hemhorrage

Question 15

Clinical targets prof aortic dissection

Answer 15

Hypertension

CT defects in that area of aorta

Atherosclerosis

Question 16

Aortic dissection pathogenesis

Answer 16

In hypertensive patients aorta shows medial degeneration that is associated with loss of medial SMC and disorganized ECM

Question 17

Aortic dissection clinical features

Answer 17

Sudden onset of excruciating Chest pain ( can be confused with MI)

Death usually result of rupture into pericardium, thorax or abdominal cavity