Common Cardiac Drugs

Overview of medication used in heart conditions
The following information gives a brief overview of the common classes of medicines prescribed for patients with heart conditions

Medicines for 'blood thinning': aspirin, clopidogrel and warfarin
  
Aspirin
Aspirin acts to reduce the 'stickiness' of platelets which are cells in the blood that can cause clots. It is commonly prescribed for patients who have angina, heart attacks, strokes, peripheral arterial disease and following bypass surgery or coronary artery stenting. Aspirin may cause indigestion, nausea, vomiting or less commonly stomach bleeding or ulceration. It may be necessary to prescribe a medication to protect your stomach from the effects of aspirin.

Clopidogrel
Clopidogrel may be used as an alternative if patients are intolerant of aspirin but the side effects may be similar. It is used in patients who are truly allergic to aspirin (rash, wheeze, swelling of the lips/tongue).

Combined use of aspirin & clopidogrel
Combined use of aspirin and clopidogrel
A combination of aspirin and clopidogrel will be prescribed for some patients who have had a heart attack and for all patients following coronary artery stenting (to reduce the risk of clot formation in the stent.) For patients who have:
   1. a bare metal stent this will be for at least one month
   2. a drug eluting stent this will be for at least six months.

It is important that this combined treatment is not stopped too early. Prior to discharge from hospital your consultant team will inform you of the required duration of combined therapy and issue you with a clopidogrel information card detailing this information. Please show this card to other members of the healthcare team looking after you.

Warfarin
Warfarin is given if long term prevention of clotting is needed for example in patients with an artificial heart valve or an irregular heart rhythm (atrial fibrillation).

Regular blood tests are required to control the dosage. Prior to discharge from hospital you should be told the dose of warfarin to take until your next blood tests and the time and date for your blood test (this is usually within 4 days of hospital discharge). If you are not sure when your blood test is due please contact the ward you were discharged from for further advice.

In addition patients should

Patients are advised to carry on their person information relating to their warfarin. The National Patient Safety Agency have recently:

Please check with your doctor if you have been prescribed a combination of:

Beta-blockers
Beta blockers reduce the action of adrenaline and stop the heart from beating as fast. They are a common class of cardiac medication used for the management of angina, after a heart attack, for heart failure, for some rhythm disturbances and for the management of high blood pressure. The generic names are similar and all end in …olol. Examples are atenolol, bisoprolol, metoprolol and carvedilol.
Common side effects include tiredness, fatigue, cold hands and feet and impotence.
In patients with asthma/wheezing beta blockers should be avoided as they may worsen the breathing. When used in heart failure beta-blockers are started at a very low dosage which will need to be built up gradually.
If you feel you have any side effects with your beta-blocker please consult your doctor as they should not be stopped abruptly.

ACE inhibitors
By reducing the effect of the 'hormone' angiotensin these medicines help the arteries in the heart to relax and widen. They are used for the management of high blood pressure and also to treat and prevent heart failure. The generic names are similar and all end in ….pril. Examples are ramipril, perindopril, lisinopril.
The most common side effect described with ACE inhibitors is a dry cough, which tends to be worse at night and unresponsive to cough remedies. If you develop this side-effect please discuss this with your doctor.
Before starting on these medicines and/or a few days after any dosage increase a you will have your blood pressure monitored and a blood test is required to check the function of the kidney.

Angiotensin II receptor antagonists are similar in action to ACE inhibitors and may be used as an alternative - particularly in cases where the ACE inhibitor is not tolerated due to the side-effect of cough. Again the generic names are similar and all end in ….sartan. Examples include candesartan, irbesartan, and losartan.

Nitrates
Nitrates exert their effects by dilating (opening up) the blood vessels that supply the heart and thus reduce the symptoms of angina. They can be used to:
1. Give immediate relief of symptoms: sublingual nitrates which are in the form of tables or sprays under the tongue.
2. Prevent symptoms of angina: tablets or patches that are applied to the skin or use of sublingual preparations in advance of an activity.

How to use glyceryl trinitrate (GTN) sublingual tablets or spray
Many people who have angina always carry their GTN with them. The dose is taken under your tongue 'as required' when a pain develops. GTN is absorbed quickly into the bloodstream from under the tongue. A dose works to ease the pain within two-three minutes. If the first dose does not work, take a second dose after five minutes. (If the pain persists for 10-15 minutes despite taking GTN, then call an ambulance.)
GTN tablets 'go off' after a few weeks. Until the container has been opened this is not a problem however once the container has been opened a fresh supply of tablets is needed after 8 weeks. GTN spray which has a much longer shelf life (lasts until the expiry date printed on the container)
Common side-effects associated with GTN are headaches, facial flushing and light-headedness/dizziness.

Calcium channel blockers
Also known as calcium antagonists these medicines may be split into three types: verapamil, diltiazem and the dihydropyridines (which all end in ….pine: examples are amlodipine and nifedipine), They medicines are used for the management of high blood pressure, angina and to slow the heart rate down (verapamil and diltiazem only). Other medications used for angina are nicorandil and ivabradine.

Diuretics ('water tablets')
Commonly known as water tablets these medicines help the body to remove water. Water tablets may be useful to reduce blood pressure or in the treatment of heart failure to prevent the build up of fluid in the lungs or in the tissues which may lead to swollen ankles/legs or a swollen stomach. If fluid builds up in the lungs this may lead to shortness of breath on exertion or at rest, difficulty lying flat to sleep (or needing extra pillows) or night time waking with breathlessness. In addition build up of fluid may result in an increase in body weight.

The classes of water tablets are known as: Thiazides (e.g. bendroflumethiazide), Loop diuretics (e.g. furosemide, bumetanide), Aldosterone antagonists (e.g. spironolactone)

As well as removing water diuretics may also remove salts from the body. You should reduce the amount of salt in your diet, including avoiding adding salt to your food (www.bhf.org.uk/publications.aspx?sPage=2 ).
When taking diuretics you may need to have a blood test to check the level of salts (in particular potassium) or the function of your kidney. Your doctor will advise you on when these tests are needed.

Cholesterol lowering medicines (statins)
The most commonly prescribed medicines for lowering the cholesterol are known as the statins (e.g. simvastatin, atorvastatin) which work by blocking the production of cholesterol by the liver. Medication should not be considered as an alternative to adopting a healthy heart diet!! (www.bhf.org.uk/publications.aspx?sPage=2)

The current school of thought is that, regardless of the cholesterol level, statins should be prescribed for all patients who have:

In these patient groups the target cholesterol levels are a total cholesterol of ? 4 mmol/l and LDL cholesterol of ? 2 mmol/l and an HDL level of ? 1mmol/l.
Most people who take a statin have no side-effects, or only minor ones. These include: headache, pins and needles, abdominal pain, bloating, diarrhoea, feeling sick, and a rash. However, you should tell your doctor if you have any unexpected muscle pains, tenderness or weakness. This is because a rare side-effect of statins is a severe form of muscle inflammation.
Patients who are prescribed simvastatin should avoid grapefruit juice as a substance in this fruit juice leads to high levels of simvastatin in the blood stream - making the side effects on the muscle more likely. This effect occurs to a lesser extent with atorvastatin (intake of grapefruit juice should be kept low) but not with the other drugs in this class
Other cholesterol lowering medicines may be used as an alterative to statins, or in addition to statins of cholesterol targets cannot be attained by a statin alone. These are most commonly either a fibrate (e.g. fenofibrate) or ezetimibe.

Fish oils may be used as part of a lipid lowering regime or may be used to supplement dietary intake in patients who have had a heart attack. The particular type of fish oils recommended are known as omega-3 fatty acids and are contained oily fish such as mackerel and sardines. Your doctor may prescribe this as Macron®

Medicines for rhythm disturbances
Commonly prescribed classes of medicines for rhythm disturbances are beta blockers (see peviously), digoxin and amiodarone.

Digoxin
Digoxin is commonly used for the reducing the heart rate in atrial fibrillation (AF). As a result the heart rate will be slowed and the symptoms of AF for example breathlessness, palpitations or chest pain will be reduced.
Side effects include loss of appetite, nausea, confusion, and visual disturbances.

Amiodarone
Amiodarone is very effective at controlling a wide range of rhythm disturbances. However, it does have a number of important side effects that require careful monitoring.
Amiodarone makes the skin more sensitive to sunlight - direct sunlight and sun through glass. You should avoid exposure to too much sun and use a high factor sun block.
Small amounts of the medicine deposit in the eye. These do not generally affect vision however we recommend that you have an eye test annually at your optician and report any changes in your vision to your doctor.
Some patients report difficulties with night driving due to increased sensitivity to the glare from oncoming headlights.
Before starting amiodarone your doctor should do a blood test to check that you thyroid and liver function is alright. Once on treatment this test should be repeated every 6 months.
You may need a chest X-ray or tests for the function of your lungs. During treatment if you develop shortness of breath you should consult your doctor.

If you are taking warfarin and this medicine is started or stopped always inform your doctor as you will need close monitoring for the affects on your warfarin dose.

Other medications for rhythm disturbances include verapamil, mexiletene, flecainide, and propafenone