Understanding Low Ejection Fraction: Signs, Symptoms, and Treatment Options

Heart failure affects millions of people globally, and one of the most important metrics used to assess cardiac function is ejection fraction. Whether you have been recently diagnosed or are supporting someone through a cardiac condition, knowing the basics of ejection fraction, its causes, symptoms, and how it is diagnosed can help you make more informed decisions about care.

What is ejection fraction and how is it measured?

Ejection fraction refers to the percentage of blood the left ventricle pumps out with each heartbeat. A normal ejection fraction typically falls between 55% and 70%, meaning the heart pushes out more than half its blood volume with every contraction. When this figure drops below 40%, it is generally classified as low, or reduced ejection fraction, often referred to medically as HFrEF (heart failure with reduced ejection fraction). This measurement is most commonly obtained through an echocardiogram, a non-invasive ultrasound of the heart, though it can also be assessed via cardiac MRI, nuclear stress tests, or a CT scan.

Common causes and risk factors for low ejection fraction

A number of underlying conditions can contribute to a reduced ejection fraction. Coronary artery disease is one of the most frequently cited causes, as blockages in the arteries limit blood flow to the heart muscle, weakening it over time. Other contributing factors include previous heart attacks, high blood pressure, diabetes, certain viral infections that affect the heart muscle (myocarditis), and long-term alcohol use. Genetic conditions such as dilated cardiomyopathy can also play a role. Risk increases with age, and lifestyle factors such as smoking, obesity, and physical inactivity may accelerate the deterioration of heart function. Some chemotherapy treatments have also been associated with reduced cardiac output as a side effect.

Signs, symptoms, and when to seek medical help

The symptoms of low ejection fraction often mirror those of heart failure more broadly. Fatigue and shortness of breath, particularly during physical activity or when lying flat, are among the most reported experiences. Swelling in the legs, ankles, or feet caused by fluid retention is another hallmark sign. Some individuals notice a persistent cough, rapid or irregular heartbeat, reduced ability to exercise, or difficulty concentrating. Sudden weight gain from fluid buildup can also occur within a short period. If you or someone you know experiences chest pain, severe breathlessness, or fainting, emergency medical attention should be sought immediately. Even milder symptoms that are new or worsening deserve prompt evaluation by a healthcare provider.

This article is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for personalized guidance and treatment.

Diagnostic tests and interpreting results

Diagnosing a low ejection fraction typically begins with a thorough clinical examination followed by targeted testing. An echocardiogram remains the most widely used diagnostic tool due to its accessibility and real-time imaging capability. Blood tests, including BNP or NT-proBNP levels, can indicate cardiac stress, while an electrocardiogram (ECG) helps identify rhythm abnormalities. In some cases, a cardiac catheterization may be recommended for a more detailed assessment of the heart’s structure and blood flow. Interpreting results requires clinical context since ejection fraction alone does not tell the full story. A cardiologist will consider all findings together to determine the severity of the condition and the most appropriate course of action.

Treatment approaches for low ejection fraction

Managing a low ejection fraction typically involves a combination of medication, lifestyle changes, and in some cases, device or surgical interventions. Commonly prescribed medications include ACE inhibitors or ARBs to relax blood vessels, beta-blockers to reduce heart strain, and diuretics to manage fluid retention. SGLT2 inhibitors, originally developed for diabetes, have shown significant benefits for heart failure patients in recent clinical studies. Cardiac resynchronization therapy (CRT), which uses a specialized pacemaker, can improve the coordination of heart contractions in eligible patients. In severe cases, implantable cardioverter-defibrillators (ICDs) may be recommended to prevent life-threatening arrhythmias. For end-stage cases, a heart transplant or ventricular assist device may be considered. Lifestyle modifications such as limiting sodium intake, avoiding alcohol, maintaining a healthy weight, and engaging in medically supervised physical activity are also central to long-term management.

Understanding low ejection fraction is a meaningful step toward managing heart health more effectively. With the right combination of medical care and lifestyle awareness, many people with reduced ejection fraction are able to maintain a good quality of life and slow the progression of their condition.