Systolic (i.e. Pumping) Function: An Overview

Systolic function refers to the heart’s ability to contract and pump blood out of the ventricles into the arteries, supplying oxygen-rich blood to the body. Healthy systolic function is vital for maintaining adequate blood flow and ensuring that the body’s organs and tissues receive the oxygen they need.

This page covers the essential aspects of systolic function, including its definition, the seriousness of impaired systolic function, its types, symptoms, causes, and treatments. Additionally, we explore the role of heart scans in diagnosing systolic dysfunction and emphasise the importance of seeking care from a professional cardiac clinic.

What is Systolic Function?

Systolic function refers to the phase of the cardiac cycle in which the heart’s ventricles contract to pump blood out of the heart and into the arteries. During systole, the left ventricle pumps blood into the aorta, which then delivers it to the rest of the body, while the right ventricle pumps blood into the pulmonary artery, sending it to the lungs for oxygenation.

The efficiency of systolic function is critical for maintaining an adequate cardiac output, which is the amount of blood the heart pumps each minute. Systolic function is often assessed by measuring the ejection fraction (EF), which is the percentage of blood ejected from the left ventricle with each heartbeat. A normal ejection fraction typically ranges from 50% to 70%.

How Serious Is It? & Are There Different Types?

Impaired systolic function, also known as systolic dysfunction, is a serious condition that can lead to heart failure and other cardiovascular complications if left untreated. The severity of systolic dysfunction can vary, and it is often classified based on the ejection fraction:

1. Mild Systolic Dysfunction: In this stage, the ejection fraction is slightly reduced (40%-49%). The heart’s ability to pump blood is mildly impaired, but the patient may not experience significant symptoms.
2. Moderate Systolic Dysfunction: The ejection fraction is moderately reduced (30%-39%). The heart’s pumping efficiency is significantly impaired, and symptoms such as shortness of breath and fatigue may begin to appear.
3. Severe Systolic Dysfunction: The ejection fraction is severely reduced (below 30%). The heart is unable to pump blood effectively, leading to symptoms of heart failure, such as severe shortness of breath, swelling, and exercise intolerance.

Systolic dysfunction can lead to a condition known as heart failure with reduced ejection fraction (HFrEF), where the heart’s ability to pump blood is significantly diminished, leading to insufficient blood flow to meet the body’s needs.

Symptoms

The symptoms of systolic dysfunction can vary depending on the severity of the condition and may include:

• Shortness of breath: Especially during physical activity or when lying down, as the heart struggles to pump blood efficiently.
• Fatigue: A persistent feeling of tiredness, even with minimal exertion, due to inadequate blood flow to the muscles and tissues.
• Swelling: Particularly in the legs, ankles, and feet, as fluid builds up due to poor circulation and heart failure.
• Chest pain or discomfort: Often due to reduced blood flow to the heart muscle itself.
• Palpitations: Sensations of irregular, rapid, or forceful heartbeats, as the heart tries to compensate for reduced pumping efficiency.
• Exercise intolerance: Difficulty performing physical activities that were previously manageable, often due to reduced cardiac output.

Causes

Systolic dysfunction can result from a variety of underlying conditions or factors:

• Coronary artery disease (CAD): Blockages in the coronary arteries can reduce blood flow to the heart muscle, leading to damage and impaired systolic function.
• Heart attack (myocardial infarction): A heart attack can cause permanent damage to the heart muscle, reducing its ability to contract and pump blood effectively.
• Hypertension: Chronic high blood pressure can strain the heart over time, leading to thickening of the heart muscle (left ventricular hypertrophy) and eventually to systolic dysfunction.
• Cardiomyopathy: Diseases of the heart muscle, such as dilated cardiomyopathy, can weaken the heart’s ability to contract, leading to systolic dysfunction.
• Valvular heart disease: Conditions affecting the heart valves, such as aortic stenosis or mitral regurgitation, can increase the workload on the heart and contribute to systolic dysfunction.
• Diabetes: High blood sugar levels can damage the heart muscle and blood vessels, leading to impaired systolic function.
• Obesity: Excess body weight can strain the heart and contribute to the development of systolic dysfunction.

Treatments

Treatment for systolic dysfunction focuses on managing the underlying causes, alleviating symptoms, and improving heart function. Treatment options include:

• Lifestyle changes: Adopting a heart-healthy lifestyle is crucial for managing systolic dysfunction. This includes regular exercise, a balanced diet, weight management, and quitting smoking.
• Medications: Various medications may be prescribed to manage symptoms, reduce the workload on the heart, and improve its function. These may include beta-blockers, ACE inhibitors, angiotensin II receptor blockers (ARBs), diuretics, and aldosterone antagonists.
• Implantable devices: In some cases, devices such as implantable cardioverter-defibrillators (ICDs) or biventricular pacemakers (cardiac resynchronization therapy) may be recommended to help manage heart rhythm and improve systolic function.
• Surgical intervention: For patients with severe systolic dysfunction due to coronary artery disease or valvular heart disease, surgery may be necessary to restore blood flow to the heart muscle or repair/replace damaged heart valves.

The Role of Heart Scans in Identifying The Issue

Heart scans are essential for diagnosing systolic dysfunction and assessing its severity. These imaging tests allow cardiologists to evaluate the heart’s structure, measure ejection fraction, and identify any underlying conditions contributing to the dysfunction. Common heart scans used in diagnosing systolic dysfunction include:

• Echocardiogram: An ultrasound of the heart that provides detailed images of the heart’s chambers and valves. It is the primary tool for assessing ejection fraction and evaluating systolic function.
• Cardiac MRI: Offers a comprehensive view of the heart’s structure and function, including precise measurements of ejection fraction and muscle damage.
• Nuclear Stress Test: Measures how well the heart pumps blood during exercise or stress, helping identify areas of the heart that may not be receiving enough blood.
• Cardiac CT Scan: Provides high-resolution images of the heart’s anatomy, helping to identify blockages in the coronary arteries or structural abnormalities that may contribute to systolic dysfunction.

The Importance of Trusting a Professional Cardiac Clinic

Given the complexity and potential seriousness of systolic dysfunction, it is essential to seek care from a professional cardiac clinic with experienced cardiologists and access to advanced diagnostic tools. A specialised cardiac clinic can provide accurate diagnoses, develop personalised treatment plans, and offer ongoing care to manage the condition effectively. Trusting a professional cardiac clinic ensures that patients receive the highest standard of care, which is critical for preventing complications, improving symptoms, and enhancing long-term outcomes.

In conclusion, systolic dysfunction is a significant cardiac condition that requires careful monitoring and appropriate treatment. Understanding its symptoms, causes, and treatment options, along with the importance of professional care, is essential for managing the condition effectively and maintaining a better quality of life.