4. HTN/HF Part 1

What are the major effects of angiotensin II?

Vasoconstriction

↑ thirst

↑ aldosterone release

↑ ADH release

Angiotensin II causes what vascular effect?

Vasoconstriction

Angiotensin II stimulates release of what hormones?

Aldosterone from adrenal

ADH from pituitary

Major effects of aldosterone?

↑ Na reabsorption

↑ H2O retention

↑ K excretion

Aldosterone increases reabsorption of which electrolytes besides sodium?

Bicarbonate (HCO3-) and chloride

What happens to water retention when aldosterone increases?

It increases

What happens to potassium excretion with aldosterone?

It increases

ACE inhibitor suffix?

-pril

Most common ACE inhibitor (MC)?

Lisinopril

ACE inhibitors are first-line for HTN in what populations?

Diabetics and patients with heart failure

ACE inhibitors improve survival after what cardiac event?

Myocardial infarction (MI)

ACE inhibitors decrease development of what condition?

Heart failure

ACE inhibitors decrease what in HF patients?

Afterload

ACE inhibitor mechanism of action?

Block angiotensin II formation → ↓ aldosterone and ADH → ↓ Na/H2O retention → ↓ BP

ACE inhibitors block what hormone?

Angiotensin II

ACE inhibitors decrease secretion of what hormones?

Aldosterone & ADH

ACE inhibitors effect on electrolytes/H2O?

↓ Na reabsorption

↓ K excretion

↓ H2O reabsorption

ACE inhibitors lower BP by decreasing what?

Peripheral resistance and fluid retention

Why are ACE inhibitors considered renal protective in diabetes?

Decrease progression of diabetic nephropathy

What arteriole constricts during renal hypoperfusion?

Efferent arteriole

Why can ACE inhibitors precipitate acute renal injury?

Prevent efferent arteriole constriction during renal hypoperfusion

ACE inhibitors keep which renal arteriole dilated?

Efferent arteriole

Why are kidneys vulnerable in chronic HTN?

Damaged renal arterioles

What kidney finding in diabetes contributes to kidney damage?

Proteinuria

ACE inhibitor angioedema can occur when?

Months to years after initiation

Why do ACE inhibitors cause cough?

↑ Bradykinin

Major metabolic electrolyte abnormality with ACE inhibitors?

Hyperkalemia

Hyponatremia

Dangerous potassium level (value)?

Serum K+ >5.5 mEq/L

Major adverse rxns of ACE inhibitors?

Angioedema

Cough (dry)

Excess K (hyperkalemia)

Impotence

Renal failure

Oligohydramnios

ACE inhibitors are pregnancy category?

Category X

ACE inhibitors are contraindicated in which states?

- Pregnancy

- Renal artery stenosis (→ renal hypoperfusion → acute renal failure)

- Hx of angioedema

- Cross-sensitivity (allergic to 1, allergic to all)

ACE inhibitors increase hypotension risk when combined with what?

Diuretics, anesthesia, excessive alcohol

What decreases absorption of ACE inhibitors?

Antacids

What medication class may reduce ACE inhibitor antihypertensive effect?

NSAIDs

Why do NSAIDs reduce ACE inhibitor efficacy?

Block prostaglandins

ACE inhibitors increase levels of which medications?

Digoxin and lithium

Why avoid ACE inhibitors in renal artery stenosis?

Risk of acute renal failure

What labs should be monitored with ACE inhibitors?

Potassium and creatinine

Why monitor creatinine on ACE inhibitors?

Risk of renal injury/failure

Pertaining to ACEI, guidelines recommend against ACE inhibitor monotherapy in which population?

African Americans

What foods should patients avoid with ACE inhibitors?

High-potassium foods and salt substitutes

OTC cold medications may do what to ACE inhibitors?

Counteract antihypertensive effect

Patients on ACE inhibitors should watch for what sensory change?

Change in taste

ACE inhibitor absorption?

Rapid from intestine

ACE inhibitor distribution?

Well distributed

ACE inhibitor metabolism?

Rapid extensive metabolism with first-pass effect

ACE inhibitor excretion?

Hepatic → clearance of unchanged drug Urine/feces → metabolites

ACE inhibitor cough mechanism?

↑ Bradykinin

ACE inhibitor hallmark adverse triad?

Angioedema

Cough (dry)

Elevated K (hyperkalemia)

ARB suffix?

-artan

ARBs are first-line for HTN in what populations?

Diabetics and patients with heart failure

ARBs are useful in what populations/conditions?

Diabetic neuropathy

HF (systolic dysfunction)

Cardiac protection post-MI and stroke

ARB mechanism of action?

Block angiotensin II receptors → ↓ vasoconstriction, ↓ Na/H2O reabsorption, ↓ BP

ARBs block what receptor system?

Angiotensin II receptors

ARB blockade leads to decreased what vascular effect?

Vasoconstriction

ARB blockade decreases reabsorption of what?

Sodium and water

ARB overall BP effect?

↓ Peripheral resistance and ↓ BP

ARBs reduce BP by decreasing what?

Vasoconstriction and fluid retention

Major adverse rxn of ARBs?

Angioedema

Impotence

Renal failure

Cough

Oligohydramnios

Major metabolic electrolyte abnormalities with ARBs?

Hyponatremia

Hyperkalemia

ARBs are pregnancy category?

Category X

ARBs interact with what medications that can increase K levels?

Lithium, MAOIs, NSAIDs, K sparing diuretics increase risk of hyperkalemia

What medication class may reduce ARBs antihypertensive effect?

NSAIDs

ARBs contraindicated with what conditions? (same as ACEI)

Pregnancy

Renal artery stenosis

Hx of angioedema

Main advantage of ARBs over ACE inhibitors?

Less likely to cause cough

Guidelines recommend against ARB monotherapy in which population?

African Americans

ARB consideration: monitor for what electrolyte abnormalities?

Hyperkalemia and hyponatremia

Patient education: what should patients do after a missed ARB dose?

Take next dose ASAP; do NOT double dose

Common patient education warning with ARBs?

Can cause dizziness

ARB absorption?

Rapid from intestine

ARB distribution?

Well distributed

ARB metabolism?

Rapid extensive metabolism with first-pass effect

ARB excretion?

Hepatic → clearance of unchanged drug

Urine/feces → metabolites

ARB dangerous electrolyte abnormality?

Hyperkalemia

ACE inhibitor vs ARB major difference?

ARBs less likely to cause cough

ACE inhibitor vs ARB: shared electrolyte abnormality?

Hyperkalemia

Direct renin inhibitor medication name?

Aliskiren

Direct renin inhibitor MOA?

↓ renin → ↓ angiotensin I → ↓ angiotensin II → ↓ BP

Direct renin inhibitors decrease conversion of what protein?

Angiotensinogen to angiotensin I

Direct renin inhibitors ultimately decrease what hormone?

Angiotensin II

Direct renin inhibitor major adverse effects?

Angioedema

Renal failure

Oligohydramnios

Direct renin inhibitor electrolyte abnormalities?

Hyponatremia

Hyperkalemia

Direct renin inhibitors are pregnancy category?

Category X

Direct renin inhibitors interact with what medications that risk hyperkalemia?

Lithium, MAOIs, NSAIDs K sparing diuretics

Direct renin inhibitors interact with what medication class that may reduce efficacy?

NSAIDs

Direct renin inhibitors plus potassium-sparing diuretics increase risk of what?

Hyperkalemia

Contraindications for use of direct renin inhibitors?

DO NOT use aliskiren with ARBs or ACEIs in patients with diabetes

Why avoid aliskiren + ACEI/ARB in diabetes?

Increased risk of complications including renal injury and hyperkalemia

Direct renin inhibitor absorption?

Peak plasma concentration in 1-3 hours

Direct renin inhibitor distribution?

Well distributed

Direct renin inhibitor metabolism?

CYP3A4

Direct renin inhibitor excretion?

¼ excreted unchanged in urine

Direct renin inhibitor hallmark adverse effect?

Hyperkalemia

Direct renin inhibitor patient monitoring?

K+ and renal function

RAAS blocker class causing cough most commonly?

ACE inhibitors

RAAS blockers shared dangerous electrolyte abnormality?

Hyperkalemia

RAAS blockers shared renal contraindication?

Renal artery stenosis

RAAS blockers: what medication class commonly decreases efficacy?

NSAIDs

Beta blocker suffix?

-olol

Most common beta blocker (MC)?

Metoprolol