Cardiovascular Flashcards
What three components comprise Total Cholesterol?`
LDL, HDL, Triglyceride
What are HDL and LDL, what do they do?
High Density Lipoprotein: Removes cholesterol from plaque
Low Density Lipoprotein: Adds cholesterol to plaque
What are statins?
HMG-CoA reductase inhibitors
What do statins do?
Inhibitor HMG-CoA reductase which leads to a reduction in cholesterol synthesis. This stabilises plaque and reduces the incidence of heart attacks and cardiovascular disease
Statin side effects
Constipation, abdo pain, nausea, increased risk of type 2 diabetes. Contraindicated with renal impairment
Statin nursing considerations
Check serum lipid levels and instruct the patient not to drink alcohol to further damage their liver
How do bile sequestrants lower cholesterol?
Cholesterol is a major precursor to bile salts. Bile acid sequestrants are binding agents that bind cholesterol containing bile acids in the intestine and prevent them from being absorbed. This increases LDL receptor activity promoting hepatic uptake and subsequent breakdown of plasma LDL hence lowering plasma cholesterol concentration
Bile acid sequestrant side effects
GI symptoms
What are the four main types of drugs that treat angina?
Direct-acting vasodilators, organic nitrates, calcium channel blockers, potassium channel activators
GTN action
Relaxes smooth muscle causing vasodilation of peripheral veins and arteries. At large doses arterial dilation occurs also
GTN side effects
Throbbing headache, orthostatic hypotension, nausea, vomiting, brachycardia
GTN nursing considerations
Resolve hypovolaemia before administration to decrease profound hypotension. Advise patient to sit or lie still to avoid dizziness
How do beta blockers work?
They provide beta-adrenergic sympathetic inhibition, hence reducing the body’s response to adrenaline which results in reduction in heart rate, slowed conduction of impulses, decreased blood pressure and reduced cardiac contractility
What causes Angina?
Reduced oxygenation of the myocardium
Beta blockers nursing considerations
Drop in HR and BP. Can mask symptoms of hypoglycaemia
Name three calcium channel blockers
Amlodipine, Verapamil, Diltiazem
What suffix indicates a beta blocker?
lol
What does GTN stand for?
Glyceryl trinitrate
How do calcium channel blockers work?
They inhibit the calcium channels in smooth muscle of the vasculature responsible for muscle contraction. This results in vasodilation
Calcium channel blocker interactions
Serum levels may be increased by grapefruit juice. Great caution should be used in conjunction with beta blockers and it may enhance hypotensive effects
Calcium channel blockers nursing considerations
Check BP and HR before administration
What 7 drugs are use used to treat unstable angina?
Oxygen, GTN, Morphine, Aspirin, Beta-blockers, ACE inhibitors, Anti-coagulants such as heparin
How does aspirin treat angina?
It blocks the cyclooxygenase enzyme in the inflammatory pathway which is responsible for platelets aggregation and vasoconstriction.
Aspirin side effects
Increased RESP rate, GI symptoms, liver toxicity, increased bleeding risk
Aspirin nursing considerations
Take with food to avoid GI upset and check for signs of gastric irritation. Shouldn’t be taken within 7 days of an invasive procedure
How does morphine treat angina?
It has strong opioid effects on mu receptors. It reduces preload by decreasing venous return because of venodilation. As well as being a potent analgesic
Morphine nursing considerations
Check BP prior to administration as it can cause hypotension when given intravenously. Keep a close eye on RESP vitals as overdose can cause respiratory depression
How do ACE inhibitors work?
They prevent angiotensin I from converting into angiotensin II (which is a powerful vasoconstrictor). This reduces peripheral vascular resistance and blood pressure which reduces strain on the heart
ACE inhibitor nursing considerations
Diuretic therapy must be stopped to prevent first dose hypotension. Monitor urine for protein, assess BP prior to administration
How does Heparin work?
It prevents prothrombin converting into thrombin which provides rapid anticoagulation
Heparin indications
Thromboembolic disorders such as DVT, and complications arising from heart and vascular surgery
Heparin nursing considerations
Do not rub injection site as it can cause haematoma, rotate site regularly and monitor for signs of bleeding
What is LMWH?
Low Molecular Weight Heparin
How is LMWH different from normal Heparin?
It has increased bioavailability and provides an anticoagulant effect for longer. It’s also considered safer and requires less monitoring
LMWH indications
Used prophylactically against thromboembolic complications before, during and after surgery
LMWH nursing considerations
Should not be given IM. Regularly monitor platelet concentration throughout therapy and look for signs of bleeding
What is Warfarin?
Vitamin K antagonist
How does Warfarin work?
Interferes with vitamin K dependent synthesis of prothrombin which decreases the synthesis of vitamin K dependent anti-coagulation proteins
Warfarin indications
Prevention and management of venous thrombosis and thromboembolism in atrial fibrillation
Warfarin interactions
Interacts with alcohol and many other medications which reduces effectiveness. Caution if used with aspirin, Increased activity with cranberry juice
Warfarin nursing considerations
Has a narrow therapeutic index and its effects are heavily effected by diet, drugs and disease. Takes 24-48 to take effect. Monitor PT and INR
How do platelets form a thrombus?
They adhere to damaged endothelium and become activated. This draws other platelets which aggregate into a thrombus
What are the two types of anti-platelet drugs?
P2Y12 inhibitors, Glycoprotein receptor inhibitors
What is the gold standard therapy for ACS?
Percutaneous coronary intervention. It involves a small venous catheter with a balloon attached is used to widen arteries and remove the blockage
What is the common name for fibrinolytic drugs?
Clot-busters
Which conditions are thrombolytic drugs used for?
ST-segment elevation myocardial infarction, pulmonary embolism, acute ischaemic stroke, peripheral embolism, acute ischaemic stroke, peripheral arterial embolism and thrombose cannulae
Which drugs are fibrinolytic?
Thrombolytic
What are the contraindications for thrombolytic drugs?
Active internal bleeding, recent major trauma or surgery, recent cerebrovascular accident, bleeding disorder, haemorrhagic retinopathy, intracranial neoplasm, bacterial endocarditis, uncontrolled hypertension
Which drug is an antidote to heparin?
Protamine Sulphate
Which drug is antidote to warfarin?
Vitamin K
What is AF?
Atrial Fibrillation. An irregular and often rapid heartbeat that that is out of rhythm between the upper and lower chambers in the heart
How does Digoxin work?
It decreases heart rate and strengthens myocontractility by increasing the resting membrane potential of atrial tissue in the AV node
Digoxin indications
Congestive heart failure, AF
Digoxin side effects
Nausea, vomiting, abdo pain, arrhythmias, brachycardia
Digoxin nursing considerations
Monitor BP and HR noting any new arrythmias. Monitor renal function and look for GI disturbances
How do Class III antiarrhythmics work?
They prolong action potential duration and hence refractory period of atrial, nodal and ventricular tissues. This increases coronary blood flow by vasodilation
Which part of the cardiac cycle do Class III antiarrhythmics prolong
QT interval, time taken for ventricular depolarisation and repolarisation
