What Is Heart Failure? What Causes Heart Failure?

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Main Category: Heart Disease
Also Included In: Cardiovascular / Cardiology;  Hypertension;  Vascular
Article Date: 09 Jul 2009 - 0:00 PST

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Even though it may sound like it, heart failure does not necessarily mean that the heart has failed. Heart failure is a serious condition in which the heart is not pumping blood around the body efficiently. The patient's left side, right side, or even both sides of the body can be affected. Symptoms will depend on which side is affected and how severe the heart failure is - symptoms can be severe.

According to Medilexicon's medical dictionary, heart failure is "1. inadequacy of the heart so that as a pump it fails to maintain the circulation of blood, with the result that congestion and edema develop in the tissues; 2. resulting clinical syndromes include shortness of breath, pitting or nonpitting edema, enlarged tender liver, engorged neck veins, and pulmonary rales in various combinations.".

The number of elderly people developing heart failure is increasing in industrial countries, especially in the USA. The number of older patients hospitalized for heart failure in the US has more than doubled in the last 27 years, according to this report. Another US study found that Afro-Americans are 20 times more likely to develop heart failure before the age of 50 years compared to Caucasian-Americans. The American Heart Association says that American adults with severe heart failure see almost three times as many Medicare providers each year compared to a typical beneficiary.

Heart failure is the leading cause of death in South-East Asia. Researchers report that a variant of a gene that increases the risk heart failure seven-fold is most common amongst people in South East Asia.

Heart failure may cause problems beyond just evident physical ones. Almost half of all heart failure patients have problems with memory and other aspects of cognitive functioning, according to researchers from the University of California, Davis.

What is the difference between heart failure, heart attack, and cardiac arrest?

Many lay people confuse the three terms - they are quite different.

• Heart attack - this consists of death of heart muscle due to an occlusion (blockage) of a coronary artery. Put simply, heart muscle tissue dies. The heart muscle dies because it is starved of oxygen (because blood is not getting to it).


• Heart failure - this means the heart muscle cannot pump blood around the body effectively/properly. It is not a heart attack.


• Cardiac arrest - this means the heartbeat stops, the heart stops, blood circulation stops, there is no pulse.

Put simply - a heart attack means heart cells die due to lack of oxygen, heart failure means the heart does not pump blood properly, and cardiac arrest means the heart stops.

What are the signs and symptoms of heart failure?

Doctors say that by themselves the signs of heart failure may not mean the patient has heart failure and he/she should not be alarmed. However, people who have not been diagnosed with heart failure and experience more than one of the symptoms below should tell their doctor and ask for an evaluation of their heart. This article by the European Society of Cardiology explains how patients with heart failure and their families can help improve prognosis in acute events if they are taught to recognize the tell-tale signs of worsening condition and seek immediate medical help.

People who have been diagnosed with heart failure should monitor their symptoms carefully and report any sudden changes to their doctor immediately.

• Extreme fatigue (tiredness)
  
  By far the main symptom is extreme fatigue - tiredness. The patient is not getting enough blood pumped from the heart to his/her muscles. The body diverts blood away from less vital organs - muscles in the limbs - and focuses on supplying the heart and brain.

Other symptoms depend on which side of the body is not getting an adequate supply of blood:


• Heart failure on the left side of the body:
  
  
  • Breathlessness, panting (dyspnea) - this may happen at any time, but will be more noticeable or acute when the patient is active or lying down. Patients at night will often need to sit up in bed or have an urge to get some fresh air.
  • Cough
  • Frothy spit (with the cough)
  
  This happens when blood backs up in the pulmonary veins because the heart cannot keep up with the supply, causing fluid to leak into the lungs.


• Heart failure on the right side of the body:
  
  
  • Swollen ankles
  • Swollen legs
  • Enlarged liver
  • Enlarged stomach
  
  This happens because as blood flow out of the heart slows down, blood that returns to the heart through the veins backs up, causing fluid accumulation in the tissues. Kidneys find it harder to dispose of sodium and water, which in turn causes fluid retention in the tissues.


• Heart failure on both sides of the body:
  
  
  • Dizziness and/or confusion - as levels of sodium and other substances in the blood change the patient is much more likely to experience confusion, and also dizziness.
  • Nausea
  • Constipation
  • Loss of appetite - as the digestive system receives less blood the patient experiences problems with digestion and appetite.

What causes heart failure? What makes heart failure get worse?

The following conditions can cause heart failure:

• Diabetes - especially diabetes type 2.


• Obesity - people who are both obese and have diabetes type 2 have double the risk of developing heart failure, according to this study.


• Smoking - people who smoke regularly run a significantly higher risk of developing heart failure compared to lifetime non-smokers and people who gave up.


• Hypertension (high blood pressure).


• Four risk factors - high blood pressure, excessive weight, smoking and diabetes were strongly correlated with greater size of the heart's left ventricle over the short term (four years) and the long term (16 years), according to a study of more than 4,217 people.


• Waist size - A study found that waist size was a predictor of heart failure among middle-aged and older men and women, and was found to be a risk factor even when BMI (body mass index) was in the normal range.


• Heart attack (coronary heart disease).


• Depression among heart disease patients - A US study found that patients with heart disease who were then diagnosed with depression were at greater risk of heart failure.


• Inherited heart disease, such as cardiomyopathy (damage to the heart muscle).


• Congenital heart defects.


• Anemia (a deficiency of red blood cells).


• Sleep disorders - there is a link between increased probability of dying and sleep apnea among heart failure patients, according to this study.


• Hyperthyroidism (overactive thyroid gland).


• Hypothyroidism (underactive thyroid gland).


• Heart failure on the left side of the body can cause heart failure on the right side.


• Faulty heart valves.


• Myocarditis - inflammation of the heart muscle, usually caused by a virus, leading to left-sided heart failure.


• Heart arrhythmias (abnormal heart rhythms) - they may cause the heart to beat too fast, creating more work for the heart. Eventually the heart may weaken, leading to heart failure. If heartbeat is too slow not enough blood may get out from the heart to the body, leading to heart failure.


• Atrial fibrillation - patients with atrial fribrillaiton have a much higher risk of hospitalization due to heart failure, a study found.


• Emphysema (a chronic disease that makes it hard for the patient to breathe).


• Lupus (person's own immune system attacks healthy cells and tissues).


• Hemochromatosis (pathology in which iron accumulates in the tissues).


• Amyloidosis (one or more organ systems in the body accumulate deposits of abnormal proteins).

How is heart failure diagnosed?

Several novel biomarkers that can be used to diagnose heart failure risk, to predict outcome and to tailor treatment to individuals have been identified (2009), according to this report.

UT Southwestern Medical Center researchers found that patient history and physical examination, traditionally the cornerstone diagnostic tool for medical care, may still be among the most accurate and cost-efficient methods to assess patients with congestive heart failure.

Most people will initially see their GP (general practitioner, primary care physician) if they have symptoms. The GP will discuss the symptoms with the patient. If the doctor suspects heart failure he may recommend a number of tests, these include:

• Blood and urine tests - these will check the patient's blood count and liver, thyroid, and kidney function. The doctor may also want to check the blood for specific chemical markers of heart failure, such as BNP (brain natriuretic peptide) - this hormone is secreted at high levels by the heart if it is injured or overburdened, but is first identified in the brain.


• Chest X-ray - an X-ray will show whether the heart is enlarged. It will also show whether there is fluid in the lungs. Other conditions other than heart failure which may have similar signs and symptoms may be detected with a chest X-ray.


• An ECG (electrocardiogram) - this device records the electrical activity and rhythms of the patient's heart. Electrodes are attached to the patient's skin and impulses are recorded as waves and displayed on a screen (or printed on paper). The test may also reveal any damage to the heart from a heart attack. Heart attacks are often the underlying cause of heart failure.


• An echocardiogram - this is an ultrasound scan that checks the pumping action of the patient's heart. This test also helps distinguish systolic heart failure from diastolic heart failure (the heart is stiff and does not fill properly). Sound waves are used to create a video image of the patient's heart, which helps the doctor see how well the heart is pumping. The doctor measures the percentage of blood pumped out of the patient's left ventricle (the main pumping chamber) with each heartbeat - this measurement is call the ejection fraction.
  
  An ejection fraction is a crucial measurement which determines how well the heart is pumping. It is used to help classify heart failure and determine the best treatment. A healthy heart pumps out approximately 60% of the blood that fills the ventricle with each beat - a healthy heart has an ejection factor of 60%.

The doctor may also carry out the following additional tests:

• Stress test - the aim here is to stress the heart and study it. The patient may have to use a treadmill or exercise machine, or take a medication that stresses the heart. Sometimes nuclear medicine or echocardiographic techniques are used to take pictures of the heart to find out whether there are any blockages in the heart arteries - such a blockage could be causing the heart failure. An oxygen uptake stress test will determine how well the patient's body is making up for his/her condition.


• Cardiac MRI (magnetic resonance imaging) or CT (computed tomography) scan - they can measure ejection fraction as well as the heart arteries and valves. They can also determine whether the patient had a heart attack. These scans are also useful in seeking out unusual heart failure causes.


• Angiogram (coronary catheterization) - a catheter (thin, flexible tube) is introduced into a blood vessel until it goes through the aorta into the patient's coronary arteries. The catheter usually enters the body at the groin or arm. A dye is injected through the catheter into the arteries. This dye stands out on images created by an X-ray and helps doctors detect coronary artery disease (arteries to the heart that have narrowed) - another cause of heart failure.

What is the treatment for heart failure?

Damage to the heart's pumping action caused by heart failure cannot be repaired. Nevertheless, current treatments can significantly improve the quality of life of the patient by keeping the condition under control and helping relieve many of the symptoms. Treatment also focuses on treating any conditions that may be causing the heart failure, which in turn lessens the burden on the heart. A GP or cardiologist will discuss treatments options with the patient and suggest the best choices, depending on individual circumstances.

Some of the treatments include:

• Stem cell therapy
  
  Stem cell therapy is still in its initial stages regarding heart failure. However, studies have provided promising results so far, as this article reveals.
  
  Long-term gene therapy resulted in improved cardiac function and reversed deterioration of the heart in rats with heart failure, according to a study carried out by researchers at Thomas Jefferson University's Center for Translational Medicine.


• Medications
  
  Patients aged 80 or more who suffer from a certain type of heart failure do not appear to benefit from most commonly prescribed heart medications, according to a study conducted at the Cedars-Sinai Heart Institute - these patients have heart failure but an ejection fraction of at least 50 percent.
  
  
  • ACE inhibitors (inhibitors of Angiotensin-Converting Enzyme) - these drugs help the arteries relax, lower blood pressure, making it easier for the heart to pump blood around the body - they lower the heart's workload. Ace inhibitors generally boost the performance of the heart and invariably improve the quality of life of the heart failure patient. These drugs are unsuitable for some patients, though. They can cause an irritating cough in some people.
  
  
  • Diuretics - these help patients with swollen ankles. They also relieve breathlessness caused by heart failure. Diuretics remove water and salt from the kidneys in the urine. There are three main types of diuretics - loop diuretics, thiazide diuretics and potassium-sparing diuretics.
  
  
  • Anticoagulants - these drugs make it harder for the blood to clot; they help thin the blood and help prevent a stroke. The most commonly used anticoagulant is Warfarin. However, it has to be carefully monitored by the doctor to ensure the blood thinning effect is not excessive.
  
  
  • Digoxin - a drug for patients with a fast irregular heart rhythm. Digoxin slows down the heartbeat.
  
  
  • Beta-blockers - some heart failure patients benefit from beta-blockers. Patients with asthma should not take them.
  
  
  • Antiplatelet medicine - these stop the blood platelets from forming clots in the blood. Aspirin is an antiplatelet drug. If the patient is taking warfarin he/she should not take aspirin. Patients who take low-dose aspirin for heart failure will need to continue taking it for the rest of their life.

Preserving kidney function - Mayo Clinic cardiology researchers found a peptide (a unique link of amino acids) that helps preserve and improve kidney function during heart failure, without affecting blood pressure.


• Surgery
  
  Not everybody with heart failure responds to drug treatment. However, there are several devices which may be implanted, such as LVADs (left-ventricular assist devices), pacemakers, or cardioverter defibrillators. Another option for people with severe heart failure is to have a heart transplant.
  
  A type of surgery which reshapes the scarred left ventricle, the main pumping chamber of the heart, and is often done in conjunction with heart bypass, not only failed to reduce deaths and hospitalizations in heart failure patients but also did not improve patients' quality of life compared to bypass alone, a large US study found.
  
  A landmark study successfully demonstrated a 29% reduction in heart failure or death in patients with heart disease who received an implanted cardiac resynchronization therapy device with defibrillator (CRT-D) versus patients who received only an implanted cardiac defibrillator (ICD-only).


• Exercise training
  
  Patients with heart failure who participated in aerobic exercise training had modest improvements in self-reported health status compared to those patients who did not have exercise training, a study found.

Prevention

There are many things we can do regarding our lifestyles to reduce the chances of ever developing heart failure in the first place, or at least to slow down its progression. These include:

• Give up smoking.


• Eat sensibly, this includes plenty of fruit and vegetable, good quality fats, unrefined carbohydrates, whole grains, and the right amount of daily calories. This article explains how heart-healthy eating recommended for heart failure patients need not be a source of frustration or misery - even for a Frenchman.


• Do exercise regularly and stay physically active (check with your doctor).


• Go easy on your salt intake.


• Make sure your bodyweight is ideal for your height.


• Consume alcohol within your national recommended limits.


• Get at least 7 hours good quality sleep each night.


• Mental stress may be bad for the heart over the long-term. Try to find ways of reducing your exposure to mental stress.


• If you already suffer from heart failure make sure you are up-to-date with all your vaccinations, and have your yearly flu-jab.

Written by Christian Nordqvist


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