Cardiovascular Flashcards
Calcium Channel Blockers Mechanism of Action
Prevent calcium moving into cardiac and smooth muscle cells resulting in decreased cardiac muscle contraction and conduction, and vasodilation of the coronary arteries and peripheral arterioles
- Decreases cardiac output
- Decreases HR
- Decreased coronary artery spasm
Which CCB decrease heart rate significantly?
Verapamil
Diltiazem
Which CCB cause significant vasodilation?
Dihydropyridines (nifedipine, amlodipine)
Calcium channel blockers Dihydropyridines clinical use
HTN
angina
Calcium channel blockers Non-dihydropyridines–clinical use
HTN
angina
atrial fibrillation/flutter
Calcium channel blockers non dihydropyridine–toxicity
cardiac depression
AV block
hyperprolactinemia
constipation
Calcium channel blockers dihydropyridine–toxicity
peripheral edema
flushing
dizziness
gingival hyperplasia
RAAS pathway
ACE inhibitors mechanism of action
Prevent angiotensin converting enzyme from converting angiotensin I to angiotensin II (vasodilator). Also stops breakdown of bradykinin (vasodilator).
Angiotensin Receptor Blocker mechanism of action
Prevent Angiotensin II from binding to receptor.
No impact on bradykinin.
ACE Inhibitor/ARB indications
- HTN
- CHF
- Acute/post MI
- Diabetic nephropathy
- Proteinuria
- Acute MI/post
ACE inhibitor/ARB Side Effects
Dizziness, hyperkalemia, elevated renal tests, angioedema
Dry cough in ACE inhibitors
Monitor renal function and electrolytes.
Thiazide diuretic indications
1st line therapy for hypertension (decreases risk for MI and CVA in HTN)
Edema
Thiazide diuretic adverse effects
- Hypokalemia
- Dehydration
- Hyperglycemia
- Hyperuricemia
- Hyperlipidemia
- Impotence
- Hyponatremia
Loop diuretic mechanism of action
Inhibit Na/K/Cl cotransporter in the Loop of Henle which inhibits reabsorption of sodium and chloride leading to increased water excretion
Loop diuretic adverse effects
- Risk of hypokalemia, hypocalcemia, hypomagnesemia, hyponatremia
- Hyperuricemia
- Hyperglycemia
- Ototoxicity
Loop diuretic indications
Edema/fluid overload, CHF, cirrhosis, renal disease – most common use
Hypertension- less effective than thiazides at lowering BP
Potassium sparing diuretics mechanism of action
Blocks Na+ movement in, and also prevents K+ movement out of cells
Potassium sparing diuretics contraindications/caution
Use caution with other meds that may increase K (i.e. ACEI/ARB)
Caution in renal impairment
Beta Blocker Mechanism of Action
- Decreases heart rate (chronoropy)
- Decreases strength of myocardial contraction (inotropy)
- Block epinephrine and norepinphrine leading to decreased vasoconstriction
Common Beta Blocker side effects
- impotence
- exacerbation of COPD and asthma
- cardiovascular effects (bradycardia, AV block, HF)
- CNS effects (sedation, sleep alterations)
- may mask signs of hypoglycemia
Cardioselective Beta Blockers
- atenolol
- esmolol
- metoprolol
- bisoprolol
- nebivolol
Alpha blocker mechanism of action and indications
Block the alpha 1 adrenergic receptor on vascular (arteriole and venule) smooth muscle and decrease vascular resistance
Used for HTN (not a first line agent) and BPH
Alpha bockers adverse effects
- First dose phenomenon hypotension
- Reflex tachycardia
- Dizziness
- Palpitations
- Headache
- Orthostatic hypotension
High intensity statins
- Atorvastatin 40-80mg
- Rosuvastatin 20-40mg
Statin mechanism of action
- HMG CoA inhibitors prevent the production of mevalonate – the building block of cholesterol
- Reduced intrahepatic cholesterol synthesis
- Upregulates expression of LDL receptor gene = more LDL receptors on the liver = lower LDL/triglycerides and higher HDL
Statin Adverse Effects and Education
- Myalgia (can be dose dependent)
- Myopathy (can lead to rhabdo)
- Headache
- GI symptoms
- Elevated LFTs (<1% of patients)
- Increased risk for DM/hyperglycemia
- ? Cognitive decline
- Brain fog
Take at night
Ezetimibe (Zetia) Contraindication
Contraindicated in patients with liver disease also on statins
Bile Acid Sequesterants Mechanism of Action and Examples
Liver increases production of bile acids using cholesterol which is then secreted in the GI tract
Cholestyramine, colestipol, colesevelam
Bile Acid Sequesterants Adverse Effects
- GI upset
- Decreased absorption of other medications
PCSK9 Inhibitors Mechanism of Action
- PCSK9 is an enzyme that degrades LDL receptors on the liver
- Inhibitors bind to PCSK9 resulting in inhibition of receptor degredation leading to more LDL receptors lowering serum LDL
Not generally prescribed in PCP setting
Fibrates Mechanism of Action and Indication
Increase lipoprotein lipase activity causing more rapid degredation of triglycerides and LDL
Mostly used for hypertriglyceridemia
Which fibrate should be avoided with statin?
gemfibrozil
Nitrate mechanism of action and indications
- Vasodilation of the peripheral arteries and veins which decreases volume of blood returning to heart (preload) which decrease workload.
- Vasodilation of coronary arteries causes increased blood flow and oxygen to heart.
Indications include acute and chronic angina, anal fissure, CHF and MI, peri/intraoperative BP management
Short Acting Nitrate Education
Adminstration is buccal or sublingual to avoid first pass effect
Can be repeated after 5 minutes up to 3 administrations, still need to call 911
Needs to be refilled at least 1x a year (make sure unexpired)
Take while seated
Long Acting Nitrate Education
Need a 10-12 hour nitrate free period per day to avoid tolerance
Nitrate Adverse Effects and Contraindications
- Headaches
- Flushing
- Dizziness
- Hypotension
- Syncope
- Reflex tachycardia
Contraindicated with PDE-5 Inhibitors (Viagra/Cialis)
Digoxin Mechanism of Action
Cardiac glycoside: Inhibits Na/K ATPase resulting in increased cardiac contractility and decreased AVE conduction/heart rate
Digoxin indications
- Afib
- Treatment resistant heart failure
- SVT
Digoxin toxicity and treatment
Manifestations include N/V, diarrhea, blurry vision with yellow tint/halos, disorientation, weakness
Can lead to hyperkalemia and fatal arrhythmias
Treatment is digibind
