Understanding Heart Failure


TYPES OF HEART FAILURE

The heart has four chambers. The two upper chambers (atrium) and the two lower chambers (ventricles). Blood comes in from the body through the right atrium and into the right ventricle; from there it flows to the lungs, where it picks up oxygen and get "oxygenated". Then the blood comes back through the left atrium and into the left ventricle, which pumps the oxygenated blood into body. During physical activity or stress, the body will require more oxygen. When a person has heart failure, the heart cannot keep up with the body requirements. In simple term, heart failure is when the heart cant do what is expected from it.

There are two main types of heart failure. They are defined based on whether the "ejection fraction" (which indicates how well the left ventricle is able to pump) is reduced or preserved:

  1. Systolic. Also know as "heart failure with reduced ejection fraction". The heart "pumping" get weak and it doesn't squeeze normally.

  2. Diastolic. Also know as "heart failure with preserved ejection fraction". In this case, the heart is gets stiff and although pumping is preserved, it does not "relax" the way it should.

HEART FAILURE CAUSES

Heart failure is caused by a condition which damages the heart. These conditions can be reversible. Addressing these conditions can affect in a positive way the conditions, especially if diagnosed and treated in an early stage. The most common causes of heart failure include:

High blood pressure — In people with high blood pressure (also called hypertension), the heart must work harder to pump blood. The heart has to pump against the blood pressure, so the higher it is, they higher the work required and with time, can affect how it performs. It will affect how it relaxes and fill with blood. The American College of Cardiology has guidelines in the appropriate steps to treat hypertension.

Coronary heart disease — In people, the arteries that supply blood to the heart can get clogged with fatty deposits, which will form plaques. With time it will impair the flow of blood. As a result, portions of the heart muscle are deprived of oxygenated blood and the heart function will be affected. Coronary heart disease can also lead to a heart attack which can cause permanent damage. Coronary heart disease and hypertension are the leading causes of heart failure in developed countries.

Heart valve disease — A number of conditions can damage the heart valves (which normally prevent back flow of blood between chambers). Two main types exist:

  1. Valve Stenosis. The valve can become narrowed, which interferes with blood flow through the valve and increases pressure in the heart.

  2. Valve regurgitation. The valve can become leaky, causing blood to flow backward.

Sometimes, both of these things happen, and a valve becomes both narrowed and leaky. With time, the heart will enlarge and will affect how is can handle the body requirements.

Other conditions - A long list of conditions can affect the heart. Some of them include the exposure to an infectious agent (i.e. COVID SARS 19), chemotherapy agents, intense stress (Stress induced Heart Disease know as "Takasubo Cardiomyopathy"), pregnancy related or congenital heart disease.

HEART FAILURE SYMPTOMS

As the amount of blood pumped by the heart decreases, a variety of symptoms can develop, including:

● Shortness of breath

● Fatigue

● Weakness, including the legs when exercising

● Lightheadedness or dizziness

● A rapid heart rate, even while resting

● Swelling in the lower legs and feet (edema) or in the abdomen (ascites) - causing weight gain.

● Unintentional weight loss (in advanced disease)



HEART FAILURE DIAGNOSIS

Heart failure is diagnosed based upon your medical history, a physical exam, and a series of tests. These tests can tell your doctor how well your heart is working and can help determine the cause of your heart failure. Tests may include:

● Electrocardiogram (ECG) – An ECG measures the electrical activity that causes the heart to beat. An ECG may detect conditions that can cause heart failure, such as an abnormal heart rhythm or a heart attack.

● A blood test known as brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP) – BNP is a hormone produced by the heart. When a person has heart failure, the BNP or NT-proBNP level is higher than normal.

● Chest X-ray – A chest X-ray shows the size and shape of the heart and the large blood vessels in the chest. It also can show if there is fluid in the lungs, which can happen in people with heart failure.

● Echocardiogram – An echocardiogram uses ultrasound (high-frequency sound waves) to assess the size and function of the heart's chambers and the structure and function of the heart valves. This includes measuring how well the left ventricle pumps (the "ejection fraction"). A follow-up echocardiogram can be done to see if your heart function changes over time.

● Exercise testing – An exercise test (also called a "stress test") determines how well your heart performs during exercise. It is one way to look for signs of a shortage of blood supply to your heart caused by blockages in the coronary arteries. A doctor or nurse will see how your heart responds to exercise by looking at the ECG, blood pressure, and heart rate as you walk or run on a treadmill. In addition, imaging tests may be done to measure the effect of exercise on the heart.

● Cardiac catheterization – Cardiac catheterization helps to measure how well the heart is functioning and provides pictures of the coronary arteries to look for blockages. During the test, the doctor inserts a thin tube (catheter) through a large blood vessel in your groin (or arm) then advances it into the heart. A dye is injected into the catheter to view the arteries and the structure of the heart by X-ray. The pumping function of the heart can also be assessed during catheterization.

● Other imaging tests – Computed tomography (CT), magnetic resonance imaging (MRI), and nuclear scanning are all imaging tests. Doctors can use these to look at the heart muscle and coronary arteries in specific situations. For example, an MRI or nuclear scan can detect inflammation of the heart. A CT scan is sometimes used to examine the coronary arteries to look for disease.



HEART FAILURE COMPLICATIONS

Heart failure can cause symptoms and make you feel ill. It can also lead to dangerous, even life-threatening complications. Left untreated, heart failure is generally a progressive condition. The goal of treatments for heart failure is to relieve symptoms; reduce the chances that you will develop complications; and slow, stop, or reverse the progression of the underlying process.

Some common complications of heart failure include:

● Irregular heart rhythms (called arrhythmias) – These problems can make your symptoms worse; some can also cause blood clots if the abnormal heartbeat causes blood to pool in the left atrium. Clots can be dangerous because if they travel to the brain, they can lead to a stroke. Some irregular heart rhythms are life threatening.

● Kidney disease – This may be caused or worsened by heart failure, which may reduce the flow of blood to or from the kidneys. Kidney disease may also make heart failure worse.

● Liver disease – This can be caused by blood flow backing up from the heart to the liver.



HEART FAILURE TREATMENT

In most people, heart failure is a chronic (long term) condition. While there are treatments that can help with symptoms and slow the progress of heart failure, in most cases it is a chronic condition that requires life-long treatment. Treatment usually includes a combination of changes in your diet and lifestyle, medicines, and sometimes a device to protect your heart from abnormal rhythms.

Diet and lifestyle — Changes in diet and lifestyle are often recommended to treat heart failure. The most common recommendations include:

● Weighing yourself daily – To monitor your fluid levels, you will need to weigh yourself every day at the same time on the same scale (be consistent). Be sure to wear light clothing each time you weigh yourself.

● Salt and fluid needs needs to be quantified closely. Maintaining a healthy weight

● Avoiding smoking – Cigarette smoking increases your risk of having a heart attack and can worsen heart failure.

● Limiting alcohol

● Regular exercise



Medication — Medicines are often used to treat heart failure symptoms; some medicines have even been proven to prolong life. It is very important to take your medicines on time every single day. If you cannot afford or have trouble taking your medicines, talk to your health care provider.



Medicines for heart failure.

Diuretic – People with heart failure often develop swelling (also called edema) in the legs and fluid in the lungs. A diuretic (also called a "water pill") helps your body get rid of the excess fluid.

ACE inhibitor, ARNI, or ARB – Angiotensin-converting enzyme inhibitor ("ACE inhibitor"), angiotensin receptor-neprilysin inhibitor ("ARNI"), and angiotensin II receptor blocker (called "ARB") medicines all widen blood vessels and lowers blood pressure, making it easier for your heart to pump. They also directly improve heart function and have been shows to decrease the risk of dying or getting admitted to the hospital. Some examples of ACE inhibitors include enalapril and lisinopril. The ARNI sacubitril-valsartan (brand name: Entresto) has two medicines in a single pill. One is the ARB called valsartan; the other is called sacubitril, and can help your body to retain less fluid and relax blood vessels. Some examples of single-agent ARB include candesartan and valsartan.

Beta-blocker - A beta blocker can slow your heart rate and lower your blood pressure. These medicines also protect the heart from the adverse effects of certain hormones that are increased when a person has heart failure. It can take time to start working, and some people feel worse right after they start taking it. This medication can help prolong life. Some examples of beta blockers include carvedilol, metoprolol and bisoprolol.

Mineralocorticoid receptor antagonist – A mineralocorticoid receptor antagonist is a type of diuretic. It protect sthe heart from hormone effects that can happen when a person has heart failure. This medication can cause high potassium levels. Some examples of mineralocorticoid receptor antagonists include spironolactone and eplerenone.

An SGLT2 inhibitor – These medications are used to treat people with diabetes and have been shown to be of benefit to treat heart failure with reduced ejection fraction.

Nitrate with hydralazine – A nitrate and hydralazine work together to relax and expand blood vessels. This combination of medicines is sometimes used in people who cannot take an ACE inhibitor, ARB, or ARNI. It is often beneficial in African-American people with heart failure.

Digoxin – Digoxin helps the heart pump with more force. This can help reduce some of the symptoms of heart failure.



Heart rhythm treatment — In some people with heart failure, an abnormal heart rhythm (arrhythmia) develops. Some abnormal heart rhythms are treated with medications. If you have a condition that causes an abnormal heart rhythm, your doctor might recommend a device that shocks the heart and returns it to a normal rhythm. The device is called an implantable cardioverter-defibrillator (ICD). It is implanted under the skin in your upper chest.

Treatment for advanced heart failure — Heart transplantation can be helpful for some people with severe heart failure that has not responded to other treatments. However, careful screening is required to ensure that heart transplantation is appropriate. In addition, the supply of hearts available for transplant is limited, so most people must wait for months or even years before a new heart is available. People who have a heart transplant are followed closely before and after surgery, since there are numerous risks. Your doctor might recommend something called a left ventricular assist device (LVAD) instead of transplantation OR while you wait for transplantation. This device is a pump that is surgically implanted inside the chest and designed to improve blood flow to the body when the heart pump is weakened.



For more information in how the heart works, Dr. Campbell does a very detail explanation: https://youtu.be/VWamhZ8vTL4