Heart failure occurs when the heart is unable to pump enough blood to meet the body’s needs. Heart failure involving the left ventricle of the heart can be systolic or diastolic.
The left ventricle is one of four chambers of the heart. The function of the left ventricle is to pump oxygen-rich blood around the body.
Left-sided, or left ventricular, heart failure reduces the amount of blood that the left ventricle can pump around the body.
Left-sided heart failure can be either systolic or diastolic, depending on whether the issue occurs between or during heartbeats. The timing will depend on whether the problem is with the pumping or the relaxing function of the heart.
This article looks at the differences between systolic and diastolic heart failure. It also explains how doctors diagnose and treat both of these types of left ventricular heart failure.
Left-sided heart failure can cause shortness of breath, coughing, or trouble breathing, especially during physical activity.
Systolic heart failure
Systolic heart failure occurs when the left ventricle is unable to contract strongly enough when the heart beats.
With each contraction of the left ventricle, the heart pumps oxygen-rich blood out and around the body.
If the left ventricle is unable to contract fully, the body cannot get the amount of oxygen that it needs. An insufficient oxygen supply can lead to symptoms, as well as organ dysfunction.
Diastolic heart failure
Diastolic heart failure occurs when the left ventricle cannot relax properly between heartbeats.
The left ventricle fills with oxygenated blood between heartbeats, then pumps the blood around the body during a heartbeat, also known as systole.
If the left ventricle cannot fully relax, it cannot hold the amount of blood that the body needs. It can also lead to high pressure within the chambers of the heart and, in turn, increased pressure in the lungs.
Doctors diagnose systolic and diastolic heart failure using many of the same tests.
Systolic heart failure diagnosis
Doctors also refer to systolic heart failure as heart failure with reduced ejection fraction (HFrEF).
Ejection fraction is a measurement of how much blood the left ventricle pumps out each time it contracts.
The American Heart Association (AHA) note that in general, the normal ejection fraction of a heart falls between 50% and 70%, while an ejection fraction of 41–50% is borderline reduced. A person who has HFrEF may have an ejection fraction of less than 40%.
When diagnosing HFrEF, a doctor may use an echocardiogram to check a person’s ejection fraction percentage.
An echocardiogram is a test that uses sound waves to form a picture of the heart.
Diastolic heart failure diagnosis
Doctors may sometimes refer to diastolic heart failure as heart failure with preserved ejection fraction (HFpEF).
A person can have diastolic heart failure and still have a normal ejection fraction.
The left ventricle can become stiff and thick, increasing the pressure in the heart or meaning that it can hold a smaller amount of blood than usual. However, this thickened left ventricle could still appear to pump out a normal percentage of the blood that it takes in.
A doctor may also use an echocardiogram to diagnose HFpEF.
In addition, a medical team may use an electrocardiogram (EKG) to determine the thickness of a person’s left ventricle. More sophisticated imaging tests, such as cardiac MRI, can help confirm this measurement.
As part of the diagnostic process for both forms of left-sided heart failure, a doctor will likely ask the person about their symptoms and medical history.
Both systolic and diastolic heart failure have a range of treatment options.
Systolic heart failure treatment
A person’s medical care team may treat systolic heart failure with various medications, including:
- diuretics, which help reduce fluid buildup in the body
- angiotensin converting enzyme (ACE) inhibitors, which help lower blood pressure and reduce strain on the heart
- beta-blockers, to reduce the heart rate and blood pressure
- mineralocorticoid receptor antagonists (MRAs), to lower blood pressure
- angiotensin receptor blockers (ARBs), which doctors can prescribe if a person cannot tolerate ACE inhibitors
- angiotensin receptor-neprilysin inhibitors (ARNIs), a combination medication that doctors use to lower blood pressure and reduce fluid buildup
- SGLT2 inhibitors, which are a treatment for diabetes but also improve outcomes in people with heart failure
- ivabradine (Corlanor), to reduce the heart rate
- digoxin (Lanoxin), which lowers the heart rate and strengthens heart contractions
- vasodilators, to lower blood pressure
Systolic heart failure may require a person to take a combination of medications.
Research from 2016 found that taking a combination of ACE inhibitors and beta-blockers can reduce a person’s risk of death due to heart failure by
The same research also found that taking a combination of medications could reduce the risk of hospitalization for a person with HFrEF by 64%.
Diastolic heart failure treatment
Currently, there is little information on the benefit of medication for a person with diastolic heart failure.
However, a doctor may use certain medications, such as diuretics, to improve the symptoms of diastolic heart failure. Alternatively, they may prescribe beta-blockers to increase the diastolic filling time.
The treatment of diastolic heart failure may focus on managing its cause or contributing factors. This treatment may involve taking medication to control blood pressure or correct heart rhythm problems.
A doctor may recommend that people with left-sided heart failure adjust their everyday habits to increase heart health. They might suggest:
- eating a healthy diet
- moderating alcohol intake
- reaching or maintaining a moderate weight
- increasing physical activity levels
- limiting daily sodium and fluid intake to less than 1,500 milligrams and 2 liters, respectively
- quitting smoking, if a smoker, or avoiding secondhand smoke
Some people with HFrEF may need a special pacemaker or defibrillator. If a person’s left-sided heart failure worsens, they may need surgery or another medical procedure.
Surgically implanted devices
A person with left-sided heart failure may benefit from the following surgically implanted devices:
- Left ventricular assist device (LVAD): The LVAD is a mechanical pump that helps the weakened left ventricle pump blood around the body. A person can use this device while waiting for a heart transplant.
- Cardiac resynchronization therapy (CRT): The CRT is a type of pacemaker that helps the left and right ventricles contract more regularly and in sync with one another.
- Implantable cardioverter-defibrillator (ICD): Some people who have heart failure will experience irregular heartbeats, which can cause sudden cardiac arrest. An ICD monitors a person’s heart rate and uses electricity to correct irregular rhythms.
A person who receives treatment but continues to experience severe heart failure symptoms may require surgery.
Doctors may also recommend surgery if a correctable condition, such as a heart abnormality, is the cause of a person’s heart failure.
Surgeries available to a person with left-sided heart failure include:
- Heart transplantation: This form of surgery involves a surgeon replacing a person’s damaged heart with a healthy heart from a donor. It can take a long time for a person to receive a heart transplant, and this procedure only takes place when other treatments have failed.
- Corrective surgery: This type of surgery involves correcting a defect in the heart that is causing heart failure. Corrective surgery may involve replacing faulty heart valves or attaching new blood vessels to bypass blocked sections of the artery.
- Cardiac catheterization: Also known as percutaneous coronary intervention (PCI), cardiac catheterization surgery involves removing blockages in the coronary arteries.
Issues with the left ventricle cause left-sided heart failure. Left-sided heart failure can be systolic or diastolic.
Systolic heart failure occurs during a heartbeat and relates to the pumping function, whereas diastolic heart failure occurs between heartbeats and is due to an issue with the relaxing function.
A doctor can diagnose systolic and diastolic heart failure using various tests.
They treat systolic heart failure using medications. However, the treatment of diastolic heart failure focuses on its causes and symptoms.
Various surgical procedures are available to treat left-sided heart failure if other treatments prove ineffective.
A person with left-sided heart failure can discuss the treatment options that are most appropriate for them with their doctor.