Irish Pharmacy News
Tuesday 1 January 2013
CPD 25: Heart Failure
Biography – Eamonn Brady MPSI is the owner of Whelehans Pharmacy in Mullingar. He graduated from the Robert Gordon University in Aberdeen in 2000 with a Masters in Pharmacy. He worked for Boots in the UK before moving back to Ireland in 2002. He bought Whelehans Pharmacy in Mullingar in 2005. He undertakes clinical training for nurses in the midlands.
1. REFLECT – Before reading this module consider the following: Will this clinical area be relevant to my practice.
2. IDENTIFY – if the answer is no, I may still be interested in the area but the article may not contribute towards my continuing professional development (CPD). If the answer is yes, I should identify any knowledge gaps in the clinical area.
3. PLAN – If I have identified a knowledge gap – will this article satisfy those needs – or will more reading be required?
4. EVALUATE – Did this article meet my learning needs – and how has my practice changed as a result? Have I identified further learning needs?
5. WHAT NEXT – At this time you may like to record your learning for future use or assessment. Follow the 4 previous steps log and record and your findings.
Published by IPN and supported with an unrestricted educational grant from Pfizer Healthcare Ireland. Copies can be downloaded from www.irishpharmacytraining.ie
Heart Failure
Congestive cardiac failure is generally referred to as ‘heart failure’. This term is slightly deceptive because it does not necessarily mean that the heart ‘failed’.
Heart failure is when the heart does not work adequately. It cannot meet the body’s need for blood because it does not pump properly and it usually occurs because the heart muscle has become too weak, or stiff to work properly. There is a 30% mortality rate on year from diagnosis and a five-year mortality rate of 60-70%. However, survival rates are improving due to better treatment regimens. For example, six-month mortality rates in the UK have reduced from 26% in 1995 to 14% in 2005.
Heart failure affects 2% of the Irish population but is more common amongst the elderly. It affects 6% to 10% of the population over the age of 65, although the average age of diagnosis is 76. It is the leading cause of hospital admissions in the over-65s, accounting for 20% of hospital admissions in this age group.
Symptoms of heart failure can come on quickly and this is known as acute heart failure. It is more common for the symptoms to develop slowly over time, which is known as chronic heart failure. Acute heart failure is usually brought on by another major complication, such as pneumonia or heart attack. Chronic heart failure is caused by long-term factors such as high blood pressure, obesity, diabetes and smoking. Coronary artery disease is most common cause of heart failure.
TYPES OF HEART FAILURE
There are two main types of heart failure and each has different symptoms:-
• Heart failure due to left ventricular systolic dysfunction (LVSD): when the part of the heart that pumps the blood around the body (left ventricle) is not functioning properly;
• Heart failure with preserved ejection fraction (HFPEF); when the heart has difficulty filling with blood.
Symptoms of heart failure include:-
• Fatigue;
• Shortness of breath, especially with activity;
• Shortness of breath when lying flat;
• Swollen feet and ankles;
• Weight gain, over a short period of time i.e., days;
• Loss of appetite and abdominal swelling;
• Dizziness or near fainting episodes
• Irritable cough, sometimes producing frothy sputum;
• Sudden severe breathlessness waking one from sleep – this requires urgent attention;
• Confusion or difficulties in concentrating.
60 second Summary
Heart failure affects 2% of the Irish population but is more common amongst the elderly. It is affects 6% to 10% of the population over the age of 65, although the average age of diagnosis is 76.
There are two main types of heart failure and each has different symptoms.
Heart failure due to left ventricular systolic dysfunction (LVSD): when the part of the heart that pumps the blood around the body (left ventricle) is not functioning properly;
Heart failure with preserved ejection fraction (HFPEF): when the heart has difficulty filling with blood.
Many of the risk factors for heart failure can be managed either by making lifestyle changes or by medication. Reducing these risk factors will also prevent other cardiovascular diseases, such as stroke and heart attack.
The patient’s symptoms are usually the first indication of heart failure. Blood tests and an echocardiogram (ECG) can help confirm diagnosis.
Heart failure patients should avoid non-steroidal anti-inflamatory drugs (negative effect on kidney function leading to fluid retention), tricyclic anti-depressants (cardio-toxic), lithium (risk of toxicity with sodium depletion) and corticosteroids (fluid retention, hypertension).
Approximately half of all patients with heart failure in the community have preserved left ventricular ejection fraction (HFPEF). Traditionally, pharmacological research has focused on heart failure with left ventricular systolic dysfunction (LVSD) and found several drugs to be beneficial including ACE inhibitors, beta-blockers and aldosterone antagonists.
CAUSES OF HEART FAILURE
There is generally not a single cause of heart failure. It is usually a result of a number of factors including:
• Coronary heart disease, when the arteries supplying blood to the heart become blocked up with fatty materials, such as cholesterol. This is known as atherosclerosis. This is the most common cause of both heart attack and heart failure;
• High blood pressure puts extra strain on the heart and, over time, can lead to heart failure;
• Damage to the heart muscle (cardiomyopathy) can lead to heart failure. Damage can be caused by infections but also by alcohol misuse, drug abuse or sometimes as a side effect of certain medications. Heart attacks can also damage the heart muscle:
• Heart rhythm problems e.g. atrial fibrillation;
• Heart valve disease, damage or problems with the valves in the heart, due to infection, atherosclerosis or ageing;
• Anaemia (decrease in red blood cells);
• An overactive thyroid gland.
PREVENTION OF HEART FAILURE
Many of the risk factors for heart failure can be managed either by making lifestyle changes or by medication. Reducing these risk factors will also prevent other cardiovascular diseases, such as stroke and heart attack.
Lowering blood pressure
When blood pressure is high, the heart has to work harder to pump blood around the body. To cope with the extra effort the heart muscle becomes thicker over time, but eventually it becomes too stiff or weak to work properly. High BP affects up to 50% of middle aged and older people. High BP has no symptoms, so routine checks are essential, especially on those over 50. Medication can effectively reduce blood pressure.
Stopping smoking
Smoking also tends to make the blood thicker and slows down blood flow, increasing the risk of blood clots (thrombosis). It damages the linings of the arteries, causing them to block up with fatty deposits (atherosclerosis).
Reducing Cholesterol
High levels of cholesterol can cause arteries to narrow and become blocked with fatty deposits (atherosclerosis), heart attacks and strokes.
Other factors
Other factors that will reduce the risk of heart failure including losing weight, regular exercise, healthy diet, lowering alcohol levels and reducing salt.
Some causes of heart failure cannot be controlled by lifestyle. These include:
Heart rhythm abnormalities (arrhythmias)
If the heart beats too fast, it may not have enough time to fill and empty properly, which causes the heart muscle to weaken. A slow heartbeat may reduce the heart output and cause symptoms of heart failure. An irregular heart rhythm increases the risk of a blood clot (thrombosis), causing a heart attack or stroke.
Myocarditis
This is inflammation of the heart muscle and most commonly caused by a virus. This inflammation can lead to heart failure.
Damaged heart valves
The heart contains four valves that allow blood to flow one way through the heart. A leaking valve means the heart has to work harder to deal with the extra volume of blood. A narrowed valve can obstruct blood flow and reduce the amount of blood the heart can pump. Over time, either a leaking valve or a narrowed valve can weaken the heart muscle, Heart valves can be damaged during a heart attack, and some children are born with faulty valves (congenital heart disease). Valves can be repaired with a surgical operation if the damage is detected in time.
Other heart diseases present at birth
Some babies are born with a ‘hole in the heart’, which is an abnormal connection between the left and right sides of the heart. Blood can flow from one side to the other (usually left to right) causing strain on the right side of the heart, which in turn may cause heart failure to develop.
Diagnosing Heart Failure
The patient’s symptoms are usually the first indication of heart failure, blood tests and an echocardiogram (ECG) can help confirm diagnosis.
Blood Tests
Blood tests will not actually directly CONFIRM HEART FAILURE. However, they can detect other factors that may be causing heart failure such as cholesterol, anaemia, diabetes, thyroid problems or kidney disease.
Natiuretic peptide test
Blood can be tested for a substance called natriuretic peptide (also called BNP or NTproBNP). If the heart is damaged or overworked, it will secrete BNP into the blood. Therefore, higher levels can indicate heart failure. However, BNPcan be altered by other factors, meaning it cannot be used as the only diagnostic indicator of heart failure. For example, obesity or treatment with diuretics, angiotensin-converting enzyme (ACE) inhibitors, angiotension II in and aldosterone antagonists can reduce levels of BNP.
High levels of BNP can have causes other than heart failure including left ventricular hypertrophy, ischaemia, tachycardia, right ventricular overload, pulmonary embolism, chronic obstructive pulmonary disease, renal failure and sepsis. The level of BNP will not differentiate between heart failure due to left ventricular systolic dysfunction (LVSD) or heart failure with preserved ejection fraction (HFPEF).
Echocardiogram
An echocardiogram (ECG) is used to look in detail at the structure of the heart. A pulse of high-frequency sound waves is passed through the chest wall and produces a picture by bouncing back from the structures in the heart.
Heart failure patients should avoid non-steroidal anti-inflamatory drugs (negative effect on kidney function leading to fluid retention), tricyclic anti-depressants (cardio-toxic), lithium (risk of toxicity with sodium depletion) and corticosteroids (fluid retention, hypertension).
TREATING HEART FAILURE
Once diagnosed with heart failure, lifestyle changes such as reducing weight and stopping smoking can reduce the risk of further complications. Medication is also used. The aim of medication is to improve symptoms of heart failure and prevent further damage to the heart. The usual combination of medicines for heart failure includes; a diuretic; an angiotension-converting enzyme (ACE) inhibitor; a beta blocker; and an aldosterone antagonist.
Diuretics
Diuretics result in a rapid improvement in symptoms and increased exercise tolerance in more than two thirds of patients. Diuretics help to relieve ankle swelling and breathlessness caused by heart failure. They work by helping to remove water and salt from the kidneys in the urine. They are not recommended as a mono-therapy for the treatment of heart failure, it is recommended they be prescribed with an ACE inhibitor or a beta blocker.
Loop diuretics are the first choice in heart failure. Loop diuretics include furosemide and bumetanide and there is no difference in efficacy between the different types. Thiazide diuretics are less potent diuretics and are generally only used for mild heart failure or as an add-on therapy e.g. bendroflumethiazide.
The dose of diuretic is generally started at a low level and increased slowly until response. The dose may be reduced once the patient is started on optimal ACE inhibitor dosage. Low potassium level is a side effect of diuretics but, because they are normally taken with ACE inhibitors for heart failure, this is rarely a problem. NSAIDS should be avoided with diuretics as they reduce their effectiveness and concomitant use can reduce kidney function.
ACE inhibitors
Ace (angiotensin-converting enzyme) inhibitors block the conversion of the hormone angiotension 1 to angiotension 11. Angiotension 11 is a natural vasoconstrictor and also encourages fluid retention. Thus ACE inhibitors work by dilating blood vessels which makes the blood flow more easily and reduces blood pressure. This makes it easier for the heart to pump blood around the body. ACE inhibitors are recommended for mild and severe heart failure. They decrease the rate of hospitalisation, improve symptoms and increase survival in heart failure patients.
Examples of ACE inhibitors include ramipril, captopril, enalapril, lisinopril and perindopril. The most common side effect is a dry irritating cough. They should be started at a low dosage and increased every one or two weeks until response. They can cause postural hypotension (dizziness and fails from lowe blood pressure) when commenced and, therefore blood pressure should be monitored. Kidney function also needs to be monitored.
Beta-blockers
Research has shown that beta-blockers can reduce symptoms and increase survival in patients with heart failure. They are not suitable for asthmatics. Generally, they are used on patients with little or no fluid retention. They work by slowing the heart rate and, perhaps by protecting the heart from the effects of adrenaline and a related chemical noradrenaline. Dosage should be increased slowly. The beta blockers used to treat heart failure are bisoprolol, carvediol and nebivolal.
These are the only three beta blockers licensed for the treatment of heart failure. Patients who are already taking a beta blocker for a pre-existing condition such as hypertension or angina (e.g. atenolol) should be switched to a beta blocker licensed for heart failure, once they are diagnosed with heart failure due to left ventricular systolic dysfunction. Lethargy and fatigue is the most common side effect of beta blockers. They should not be stopped suddenly because this can cause a rebound effect with rapid worsening of symptoms.
A major trial indicated that nebivolol is more effective than other beta blockers at increasing survival in the over-70s age group. However, further studies have questioned the methodology of the SENIORS trial, which indicated that nebivolol is more effective than other beta blockers in controlling heart failure. The general consensus now is that nebivolol is no more effective than bisoprolol and carvedilol in treating heart failure in the over 70s.
Aldosterone antagonists
These drugs are suitable for some people with heart failure. They work in a similar way to diuretics but they can also help to heal any scarring of the heart muscle. The most widely used aldosterone antagonist is spironolactone. It is a potassium-sparing diuretic.
Regular blood screening to monitor potassium is important as aldosterone antagonists raise potassium. ACE inhibitors and angiotension receptor inhibitors also raise potassium, thus the risk of hyperkalaemia is increased further when administered with aldosterone antigonists meaning that monitoring of potassium levels is even more important. In a two year review it reduced mortality in patients with severe heart failure from 46% to 35% when used as add-on therapy to existing diuretic, ACE inhibitor and beta-block therapy.
Angiotensin receptor blockers (ARBs)
ARBs have been shown to extend life and reduce symptoms in patients with heart failure. They work in a similar way to ACE inhibitors, which is by widening blood vessels and reducing blood pressure. They tend to be used as an alternative as they do not usually cause coughs. Examples include candesartan, losartan, telmisartan and valsartan. Side effects include low blood pressure (hypotension) and high potassium levels.
Digoxin
Digoxin, related to a medicine derived from the foxglove plant, increases the strength of heart muscle contractions and can also slow down heart rate. It is recommended for people who have symptoms despite treatment
with ACE inhibitors, ARBs, beta blockers and diuretics. It is used earlier in people who have both heart failure and atrial fibrillation (where the heart is beating irregularly). Potassium levels must be monitored regularly to avoid toxicity due to hypokalaemia. This is especially important when taken with diuretics, which reduce potassium levels.
Anticoagulants
In patients with heart failure in sinus rhythm, anticoagulants should be considered for those with a history of thromboembolism, left ventricular aneurysm or intracardiac thrombus. Warfarin is the most commonly used anticoagulant, and requires careful monitoring.
Antiplatelet medicine
Antiplatelet medicine, for example aspirin 75mg, should be prescribed for patients with the combination of heart failure and atherosclerotic arterial disease (including coronary heart disease). Aspirin is not usually taken with warfarin.
Calcium channel blockers
Armlodipine is a treatment option for co-existing hypertension and/or angina in patients with heart failure but verapamil, diltiazem or short-acting dihydropyridine agents should be avoided.
PRESERVED EJECTION FRACTON
Approximately half of all patients with heart failure in the community have preserved left ventricular ejection fraction (HFPF). Traditionally, pharmacological research has focused on heart failure with left ventricular systolic dysfunction (LVSD) and found several drugs to be beneficial including ACE inhibitors, beta blockers and aldosterone antagonists. However studies of treatment in patients with preserved left ventricular ejection fraction have found no significant benefit of these drugs.
There is some limited evidence that suggests potential benefit of both beta-blockers and ACE inhibitors for HFPEF. However more studies are needed to prove the benefit of these drugs in HFPEF; this means that many patients presenting to pharmacies for these drugs to treat heart failure may not be getting any benefit from them.
OTHER NON-DRUG TREATMENT OPTIONS
Medication is the mainstay of treatment. However, in certain situations, the patient may need other treatment options. This includes pace-makers in situations where the heart beats too slowly. Cardiac re-synchronisation therapy may be required with the ventricles do not contract correctly and involves inserting a small pacemaker.
Implantable cardioverter defibrillators are used when the ventricles contract too fast and this device keeps the rhythm regular. Surgery may be required, especially in situations where the heart valves are damaged. If heart failure is related to coronary heart disease, a coronary angioplasty or a coronary artery bypass graft (CABG) may be required to help get the blood flowing to coronary arteries.
TRAVELLING
Being diagnosed with heart failure should not prevent people from travelling or going on holiday, as long as the condition is well controlled. When travelling and sitting still for a long time either in a car, bus or on a
Plane, it is important to do simple exercises to reduce the risk of deep vein thrombosis (DVT). When flying, it is important to wear flight socks or compression stockings to keep blood flowering through the legs and reduce the risk of DVT. It is important to be aware that legs and ankles may swell when flying and in severe heart failure, breathing may become more difficult.
WORSENING SYMPTOMS
Signs that indicate the condition is getting worse include:
• Shortness of breath that is not related to usual exercise or activity;
• Increased swelling of the legs or ankles
• Swelling or pain in the abdomen
• Trouble sleeping, or waking up sort of breath;
• Dry, hacking cough;
• Feeling increasingly tired, or feeling tired all the time.
As heart failure gets more severe a person may become more and more immobile. The breathlessness can get worse and become extremely distressing. Sometimes opioid analgesics may need to be prescribed to ease the feeling of breathlessness. Some patients find that pain becomes more of a problem as their heart failure worsens. Opioids can also relieve pain.