renal hypertension Flashcards
What is the definition of hypertension?
Diastolic of 90mmhg
What are the mechanisms cysts/tumors/masses cause renal HTN?
Mass effect on renal artery
Tumors can secrete renin
Tumors or highly vascular lesions can cause shunting
How does a juxtaglomerular tumor look on imaging?
Hypoenhancing soft tissue mass in the renal pelvis
What is an ask-upmark kidney?
Segmental renal hypoplasia
What is the association with ask upmark kidney?
Vesicoureteral reflux and UTI
What is a page kidney?
Trauma induced subcapsular hematoma compresses renal parenchyma and causes compression iduced renin secretion
What clinical signs suggest renal origin of HTN?
Rapid acceleration or severe HTN, severe hypertensive retinopathy
What are the effects of renin?
Cleaves angiotensinogen - > angiotensin 1 - > angiotensin II
Stimulates aldosterone, arteriolar vasoconstriction, ADH/antinatriuretic effect on proximal tubule
What causes renin secretion?
Baroreceptors in affarent arteriole
Which type of FMD is most common?
Medial dysplasia
What are the 4 types of takayasu arteritis as diagnosed on arteriography?
1 - narrowing of aortic arch or great vessels
2 - narrowing of descending thoracic and upper abdominal
3 - aortic arch vessels, abdominal aorta, and major branches
4 - pulmonary arteries
How does takayasu appear on arteriography?
Smooth tapered narrowing
What are the causes of middle aortic syndrome?
Chronic aortitis, atherosclerosis, cystic medial necrosis
What is the difference between takayasu and middle aortic syndrome?
Takayasu - slightly older with clinical aortitis (fever, elevated ESR), involvement of the great vessels
Which patients are selected for screening for renal hypertension
Age extreme (50) Recent onset of HTN Rapid acceleration of HTN Malignant hypertension Flank bruit
What is a positive renal scintigraphy scan?
Profound decrease in the perfusion of the kidney when a significant RAS is present
Where are renal vein samples obtained from? What is the cutoff ratio?
Main renal veins
> 1.5 ipsi:contra is indicative
What is the mechanism of PTA?
Fracture of the atheromatous material with dehiscence of the intima and splitting of the media
Adventitia is stretched as well
Plauqe is forced into the medial portion of the artery and heals by fibrosis
Intiima is healed with reendothelialization
What is the restenosis rate in PTA?
10-20%
When is stent placement preferred?
Poor PTA results, recurrent stenosis, renal artery dissection, and obstructive intimal flaps
Also ostial lesions, eccentric stenosis, calcified plaque
What is the efficacy of PTA in atherosclerotic renal hypertension?
75% good results with 25% cured
What is the most common cause of pediatric renal hypertension
Renal parenchymal disease (most common FMD)
What is the difference between FMD in kids vs adults
Kids - male > females, less sting of beads appearance
Adults - females > males, string of beads common
Why is PTA more successful in adults?
Kids have smaller vessels, and usually more fibrosis which isnt as amenable to dilation
