Heart failure is a serious, chronic condition where the heart muscle is unable to pump blood efficiently enough to meet the body’s needs. This inefficiency means that oxygen and nutrients are not delivered effectively to tissues, and waste products are not cleared adequately. The condition affects millions of people globally, often progressing slowly. Understanding the specific type of heart failure is important because it directs the appropriate treatment plan.
Defining Systolic Heart Failure
Systolic heart failure represents a failure of the heart’s pumping action, specifically the contraction phase. This form is formally known as Heart Failure with Reduced Ejection Fraction (HFrEF). The mechanical problem lies in the left ventricle, the heart’s main pumping chamber, which becomes weakened and unable to squeeze forcefully enough.
The measure used to define this condition is the Ejection Fraction (EF), which is the percentage of blood the left ventricle pushes out with each beat. A healthy heart typically ejects between 55% and 70% of the blood inside its chamber during a contraction. In systolic heart failure, the EF is reduced, with a value of 40% or less indicating HFrEF.
This reduced pumping ability contrasts with another major type, diastolic heart failure, where the heart muscle becomes stiff and cannot relax properly to fill with blood. In systolic failure, the muscle is flabby and weak, impairing the ability to push blood out. When the left ventricle cannot effectively empty, blood can back up, leading to congestion in the lungs and other parts of the body.
Primary Causes and Risk Factors
The primary cause of systolic heart failure is any condition that damages or over-stresses the left ventricular muscle. Coronary Artery Disease (CAD) is the most common underlying factor, causing the blood vessels supplying the heart muscle to narrow. This narrowing limits the flow of oxygen and nutrients, leading to damage.
A previous heart attack (myocardial infarction) is a direct result of CAD and a significant cause of HFrEF. It causes permanent scarring of the heart muscle, which can no longer contract effectively. Uncontrolled chronic hypertension (high blood pressure) also contributes by forcing the heart to pump against greater resistance. This prolonged strain weakens the ventricular walls, reducing their pumping power.
Other conditions leading to weakening include valvular heart disease, such as a leaky mitral valve (regurgitation) or a narrowed aortic valve (stenosis). These problems increase the volume or pressure load on the ventricle, causing it to stretch and weaken. Long-term abnormal heart rhythms (arrhythmias) and diseases of the heart muscle (cardiomyopathies) are also frequent contributors.
Recognizing the Symptoms
Systolic heart failure symptoms result from poor forward blood flow and fluid congestion. Shortness of breath (dyspnea) is a common sign, occurring because blood backs up into the lungs. This breathlessness worsens during physical activity or when lying flat, often requiring people to sleep propped up on pillows.
Persistent fatigue and generalized weakness are frequently reported, stemming from the weakened heart’s inability to deliver enough oxygenated blood to the body’s muscles and organs. Even light activities become difficult, reflecting reduced cardiac output. Fluid retention (edema) is another clear sign, manifesting as swelling typically in the legs, ankles, and feet, or extending to the abdomen.
A rapid or irregular heartbeat may be noticed, as the heart attempts to compensate for its reduced pumping force by beating faster. Other manifestations of fluid buildup can include a persistent cough or wheezing, sometimes producing a frothy, pink-tinged sputum. Sudden, unexplained weight gain of a few pounds over a couple of days can signal worsening fluid retention and should prompt medical attention.
Diagnostic Procedures and Management Overview
Diagnosing systolic heart failure requires a comprehensive evaluation, with the echocardiogram serving as the most informative tool. This non-invasive ultrasound uses sound waves to create a moving image of the heart, allowing doctors to measure the Ejection Fraction directly. Confirming an EF of 40% or less establishes the diagnosis of HFrEF.
Supporting diagnostic procedures include blood tests, notably measuring B-type natriuretic peptide (BNP) or NT-proBNP levels. These hormones are released when the heart muscle is stretched, and elevated levels suggest heart failure. An electrocardiogram (ECG) and a chest X-ray check for rhythm abnormalities or signs of an enlarged heart and fluid in the lungs.
Management focuses on reducing the heart’s workload, controlling symptoms, and slowing muscle damage progression. Medications are a mainstay of treatment, including classes designed to manage fluid retention, lower blood pressure, and lessen long-term strain. These therapies block hormonal systems that cause heart damage and help the heart muscle remodel.
Lifestyle modifications are equally important and include adhering to a heart-healthy diet with restricted sodium and fluid intake. Regular physical activity and avoiding alcohol and tobacco products are also recommended to support heart function. For advanced cases, doctors may recommend implantable devices, such as pacemakers for cardiac resynchronization therapy or implantable cardioverter-defibrillators (ICDs), to help the heart beat more efficiently and prevent sudden cardiac events.