EXAM #2: PATHOPHYSIOLOGY OF HTN Flashcards
(27 cards)
According to the JNC7, what is normal blood pressure?
Less than 120/80 mmHg
According to the JNC7, what is prehypertensive?
120-139/80-89 mmHg
According to the JNC7, what is Stage 1 HTN?
140-159/90-99 mmHg
According to the JNC7, what is Stage 2 HTN?
160+/100+ mmHg
According to JNC8, what is the target BP for patient younger than 60?
Less than 150/90 mmHg
According to JNC8, what is the target BP for an adult with DM or CKD?
Less than 140/90 mmHg
What comorbid conditions are associated with HTN?
1) IHD
2) HF
3) A-fib
4) CVA
How much does a 20 mmHg increase in BP increase risk?
It doubles it
Describe the normal changes in blood pressure that occur with age?
- Systolic and diastolic increase with age until 50 y/o
- After 50, systolic increases and diastolic decreases
*This can cause “isolated systolic HTN (ISH)”
Why is there an increase in systolic HTN with age?
- Decrease in vascular compliance b/c of a loss of “elastin”
- Elastin is replaced with collagen
What are the implications of ISH in elderly individuals?
1) Sharp peaks in pulse pressure that are not attenuated by vascular compliance
2) Transmission of force to downstream vessels that can lead to damage
What are the major mechanisms that underlie obesity related HTN?
1) Leptin induced activation of the SNS
2) Activation of the RAAS
3) Metabolic disturbances
What causes HTN induced end-organ damage?
1) Damage induced by the pressure itself
2) Cardiac remodeling from increased afterload
3) Vascular remodeling
Why does HTN lead to LVH?
- Increased afterload
- Ventricular hypertrophy ensues
*Note that remodeling is related to increased risk of MI, HF, and arrhythmia
How does ANGII caused vascuclar remodeling?
Activation of downstream signaling cascades
What is primary/essential HTN?
Product of genes/environment
What is secondary HTN?
HTN as a manifestation of:
1) CKD
2) Renovascular Disease
3) Other
*Correcting the initial insult will correct the HTN
How is central SNS activity increased in response to a drop in BP?
1) Activation of systemic baroreceptors
2) Increased SNS activity
Outline the pathophysiology of renovascular HTN.
Decreased RBF activates the RAAS system
What is the most common cause of secondary HTN that is resistant to therapy?
Obstructive sleep apnea (OSA)
How does OSA cause HTN?
1) Hypercapnia stimulates SNS
2) Augmentation of the sensitivity of the chemoreceptor mechanism,
What is pressure-natriuresis?
Ability of the kidney to respond to an increase in BP by excreting Na+ and decreasing ECF volume
What is the equation for BP?
BP= COxTPR
What causes essential HTN?
1) Augmented SNS discharge
2) Abberant responses to peripheral signals
3) Vascular dysfunction
4) Renal dysfunction
