Exam 4 Flashcards
What is the #1 modifiable risk factor to prevent CVD?
Hypertension
What risks increases as blood pressure increases?
-MI
-HF
-Stroke
-Renal disease
-Retinopathy
What ethnic group has the highest prevalence of hypertension?
African Americans
How does HTN effect African Americans?
-Increased “resistant htn”
-Develops younger ages
-More prevalent in women
-More aggressive (leads to severe end-organ damage)
-Highest death rate
How does HTN effect Hispanics?
-Less likely to receive tx
-Lowest rates of BP control
-Lowest rates of awareness of HTN and tx
How does HTN effect men?
Most at risk before early middle age
How does HTN effect women?
- 2-3x more likely with oral contraceptive use
-Preeclampsia can be an early sign of CVD
-Most at risk >64
-Harder to control in older women
What is the definition of blood pressure?
Force exerted by blood against walls of blood vessels
How does BP regulation work?
-Involves both systemic factors and peripheral vascular effects
-Important to maintain tissue perfusion during activity and rest
-The function of cardiac output (CO) and systemic vascular resistance (SVR)
-CO = SV x HR
What factors influence BP?
-Sympathetic NS
-Vascular endothelium
-Renal system
-Hormonal (endocrine system)
What happens to the Sympathetic NS when BP drops?
It activates & increases HR and cardiac contractility
What senses decreased BP in the sympathetic NS?
Baroreceptors
What do baroreceptors do when BP is low?
-Send message to vasomotor center in brainstem
-Leads to efferent nerves innervating cardiac and vascular smooth muscle cells
What happens after the activation of the SNS in response to low BP?
-Vasoconstriction in peripheral arterioles
-Renin is released from kidneys
-Increases CO and SVR
What happens after baroreceptors send a message to the nerves and muscle cells?
-Parasympathetic NS in stimulated
What does the stimulation of the PNS cause?
-Decreased HR (vagus nerve)
-CO decreases
-Results in decreased BP
Where is Norepinephrine released from?
The SNS nerve endings
What does norepinephrine do?
Activates receptors in the SA node, myocardium, and vascular smooth muscle
**Response depends on receptors present
What type of receptors do smooth muscle of blood vessels have?
a-adrenergic and b-adrenergic receptors
What is a-1?
Vasoconstriction
-Increased contractility ( +inotropic)
What is a-2?
Vasoconstriction
-Inhibits release of norepinephrine
What is b-1?
Increased:
-Contractility
-HR
-Conduction
-Renin secretion
What is b-2?
Vasodilation
What does dopamine do?
Vasodilation
Endarterectomy
Open artery and remove plaque
Patch graft angioplasty
Open artery, remove plaque, and sew patch to widen the lumen
Amputation
If necrosis, gangrene, or osteomyelitis develop
