Pathophysiology of hypertension Flashcards
normal BP according to JNC 7
systolic: less than 120
diastolic: less than 80
HTN predisposes to what major conditions?
ischemic heart disease
heart failure
atrial fibrillation
stroke
what does each incremental increase in SBP (20 mm Hg) do to risk of comorbid conditions?
doubles it
how is obesity related to BP?
as BMI increases, BP increases
what is the pathophysiology of obesity in the context of HTN?
increased leptin - increases SNS activation - RAAS and MR activation - increased renal sodium reabsorption - increased BP
essential (primary) HTN is caused by what factors?
genes
environment
behavior
physiology
what are the main causes of secondary HTN?
chronic kidney disease
renovascular disease
“other”
what reflex responds to a drop in renal BP to increase renin release?
intrarenal baroreceptors
in secondary HTN what activates the intrarenal baroreceptors?
drop in renal BP
what is the main cause of secondary HTN?
obstructive sleep apnea
what is the pathophysiology of obstructive sleep apnea on HTN?
- nocturnal hypoxia / hypercapnia
- heightened sensitivity of chemoreceptor reflex
- activation of cardiopulmonary excitatory centers
- increased sympathetic, decreased parasympathetic outflow
- increased ventilation and HR
- decreased CO2, increased O2
definition: pressure natriuresis
ability of kidneys to respond to BP by excreting more salt and water
what are the central factors related to the pathophysiology of essential HTN?
- augmented sympathetic outflow
2. aberrant responses to peripheral signals
what are the vascular dysfunctions related to pathophysiology of essential HTN?
- exaggerated response to vasoconstrictors
- depressed response to vasodilators
- remodeling
what is the renal dysfunction related to pathophysiology of essential HTN?
sodium and water handling defects
