Hypertension Flashcards
What is the definition of resistant hypertension?
uncontrolled HTN despite being on 3 antihypertensive agents, including at least one diuretic
what imaging test helps locate pheochromocytoma
MIBG imaging.
It detects tiny amounts of an injected radioactive compound taken up by pheochromocytomas or paragangliomas.
Fibromusclar dysplasia is most common in which common combination of gender and race?
white women
FMD can affect vessels other than the renal arteries. which is the most common?
Brain circulation.
what adrenal hormone is elevated in HTN associated with Cushing syndrome?
Cortisol. Cortisol has mineralocorticoid activity but is typically inactivated in the kidney by renal 11-beta-hydroxysteroid dehydrogenase unless cortisol levels are so high that they overwhelm the enzyme OR the enzyme is inactivated by glycyrrhizic acid a/w licorice
name a potential cause if a patient presents with HTN, hypokalemia, and low aldosterone. (hint: 3)
- Cushing hypercortisolism 2. liddle syndrome 3. apparent mineralocorticoid excess or real licorice intake (not twizzlers)
name a disorder that a patient with hypokalemia, HTN, high renin and high aldosterone have. (hint:3)
- reninoma 2. renal artery stenosis 3. malignant HTN
in a patient with uncontrolled HTN and CKD, which is the most important: blocking SY outflow, blocking aldosterone, or reducing ECV?
reducing ECV is most important
what is the cause of HTN that develops after blunt trauma to the kidney?
Page kidney. compression of the renal parenchyma causes renal swelling confined in the renal capsule, decreasing renal blood flow and leading to increased renin/ aldosterone HTN (HTN)
what is the BP threshold for ruling out white coat HTN?
BP > 160/100 should not be blamed on white coat HTN. Treatment is required
name 3 patient characteristics that would prompt a secondary workup for HTN?
- extremes of age, 2. significantly elevated BP 3. unprovoked hypokalemia 4. abdominal bruit 5. variable BP with tachycardia, sweting and tremor, 6. family history 7. poor response to therapy
what cells in the kidney are affected when a renin-secreting tumor is present?
Juxtaglomerular cells.
treat with ACEI, ARBs or surgery
what is the cause of hypertension when there is a difference in BP between the arms and the legs?
Coarctation of the aorta. Especially if the coarctation is distal to the left subclavian artery
when checking serum aldosterone and renin, how long should spironolactone be stopped before measurement?
2 weeks
what is deficient in apparent mineralocorticoid excess syndrome?
11-beta-hydroxysteroid dehydrogenase. This enzyme usually converts cortisol to cortisone, which means that cortisol is not available to stimulate Na retention and K wasting. It can be congenital or acquired (licorice or posaconazole) and there will be excess cortisol and low aldosterone.
how do VEGF inhibitors cause HTN?
VEGF inhibitors decreases NO production & so it increases vascular resistance
Usually the goal of HTN emergency is to decrease SBP by 25% from the baseline but there are exceptions, name 4 conditions and their goal BP
- preeclampsia, goal is SBP < 140
- intracranial hemorrhage, goal is SBP < 140
- aortic dissection, goal is SBP 100-120 within 20 minutes
- ischemic stroke (keep higher level for longer)
what disorder includes altered mental status in a person without evidence of stroke, significant HTN or characteristic findings on MRI?
posterior reversible encephalopathy syndrome (PRES)
name 3 genetic HTN syndromes that follow an autosomal dominant pattern of inheritance
- Liddle syndrome
- Glucocorticoid suppressible hyperaldosteronism
- Geller syndrome
what is a rare autosomal dominant syndrome that cause new onset or worsening HTN with hypokalemia during pregnancy?
Geller syndrome.
There is an activating mutation of the mineralocorticoid receptor. Progesterone (& spironolactone) acts as an agonist on the MR, leading to salt reabs. and K wasting. (normally, progesterone acts as an MR antagonist) The renin and aldosterone levels are low (vs primary aldosteronism which has low renin and high aldosterone)
Name 2 conditions associated with low renin, high aldosterone HTN syndrome
primary aldosteronism, glucocorticoid remediable aldosteronism
True or false, a normal serum K rules out primary hyperaldosteronism
False
what enzyme can be inhibited by substances containing glycyrrhizic acid?
11-beta-hydroxysteroid dehydrogenase
does licorice induced HTN have low or high renin and low or high aldosterone?
low renin and low aldosterone
What is the aldosterone:renin ratio and aldosterone level in primary aldosteronism?
ARR > 20
Aldosterone > 12
If the ARR and aldosterone is suggestive of primary aldosteronism, what is the next diagnostic step?
Abd CT with adrenal vein sampling
What is the lateralization ratio that suggests a unilateral adenoma?
Lateralization ratio > 4
What is the next step if the aldosterone and renin are equivocal but you still suspect underlying primary aldosteronism?
Saline suppression test
(How? Give 2L of NSS for 4 hours, with aldosterone levels pre and post)
Primary aldo: aldosterone will still be high, > 5
Treatment for liddle syndrome
Amiloride (blocks ENaC)
Liddle syndrome- gain of function mutation of ENaC; high Na, low K, volume retention suppresses renin and aldo
Treatment for glucocorticoid remediable aldosteronism (GRA)
Steroids - to suppress ACTH
GRA: ACTH causes aldosterone production
What is the next drug to add if a patient has uncontrolled resistant Hypertension, on 3 meds including a diuretic?
add spironolactone (an MR antagonist)
What is the defect in Liddle syndrome?
Gain of function mutation of ENaC, resulting in increased number of functioning ENaC
what is the genetic defect in glucocorticoid remediable aldosteronism?
an autosomal dominant condition caused by the chimeric fusion between the promoter region of the gene encoding 11β-hydroxylase, which responds to ACTH, and the gene encoding aldosterone synthase. he net effect of this defect is ACTH-dependent activation of aldosterone synthase and hyperaldosteronism, although patients with GRA often have normal potassium levels
what is the genetic defect in syndrome of apparent mineralocorticoid excess (SAME)?
autosomal recessive inheritance pattern and is caused by a deficiency of 11β-hydroxysteroid dehydrogenase enzyme type 2, which normally detoxifies cortisol to cortisone; in this condition Cortisol levels are high
What is the mechanism of HTN in a subscapular renal hematoma, aka Page Kidney?
high BP is renin mediated
What antihypertensive is contraindicated in patients with Geller syndrome
Spironolactone
What is the syndrome that causes an autosomal dominant hypertension, hyperkalemia and NAGMA?
Gordon syndrome
aka Familial hyperkalemic hypertension
What is the mutation in Gordon syndrome?
inactivating mutation in WNK4 and activating mutation in WNK1
Inactivation of WNK4 leads to increased NaCl reabsorption
Treatment for Gordon syndrome?
Thiazides and salt restriction
what enzyme can be inhibited by substances containing glycyrrhizic acid?
11-beta-hydroxysteroid dehydrogenase
does licorice induced HTN have low or high renin and low or high aldosterone?
low renin and low aldosterone
type A aortic dissection is managed, medically or surgically?
surgically
type B aortic dissection is managed, medically or surgically?
medically. give esmolol or labetalol, target SBP 100-120 in 20 minutes
Treatment for liddle syndrome
Amiloride (blocks ENaC)
Liddle syndrome- gain of function mutation of ENaC; high Na, low K, volume retention suppresses renin and aldo
Treatment for glucocorticoid remediable aldosteronism
Steroids - to suppress ACTH
GRA: ACTH causes aldosterone production
what is the pathophysiology of alcohol induced hypertension?
related to increased intracellular calcium in the arterial smooth muscle cells caused by excess alcohol consumption
what resistive index is suggestive of renovascular hypertension?
resistive indices > 0.7
a patient with controlled hypertension but non-dipping pattern should undergo what type of testing?
polysomnography to evaluate for OSA
what is the target BP in the management of hypertensive urgency?
treat with oral antihypertensives, with goal BP reduction of 25% over 48 hours
