Heart failure with preserved left ventricular systolic function, often called Heart Failure with Preserved Ejection Fraction (HFpEF), is a distinct form of heart failure. This condition means the heart cannot effectively pump blood throughout the body despite a seemingly normal pumping action. Its prevalence has been increasing. Approximately half of all individuals diagnosed with heart failure have this type.
Understanding Preserved LV Systolic Function
Left ventricular (LV) systolic function describes the pumping action of the heart’s main chamber, the left ventricle. This chamber contracts to push oxygenated blood to the body. In “preserved” LV systolic function, the ejection fraction (EF)—the percentage of blood pumped out with each beat—is normal, defined as 50% or greater.
Despite this normal ejection fraction, the heart muscle in HFpEF becomes stiff. This stiffness impairs the heart’s ability to relax and fill with blood during diastole, the resting phase between beats. Consequently, even though the heart contracts well, it cannot take in enough blood to meet the body’s demands, especially during physical activity. This contrasts with Heart Failure with Reduced Ejection Fraction (HFrEF), where the heart muscle is weakened and cannot pump blood effectively, resulting in a lower ejection fraction, typically 40% or less. HFpEF is a serious form of heart failure, leading to symptoms and a reduced quality of life.
Underlying Causes and Risk Factors
Many conditions and factors contribute to preserved LV systolic function. Uncontrolled high blood pressure, or hypertension, is a frequent contributor, affecting 80% to 90% of HFpEF patients. Over time, chronic hypertension can cause the left ventricle to thicken and stiffen, hindering its ability to relax and fill with blood. Diabetes mellitus is another significant factor, with at least one-third of HFpEF patients having this diagnosis.
Obesity is a major risk factor, as over 80% of individuals with HFpEF are obese. Excess weight can lead to changes in heart structure and function, including increased stiffness. Advanced age is strongly associated with new onset HFpEF, as aging promotes changes in the heart muscle and blood vessels. Other conditions like sleep apnea, chronic kidney disease, atrial fibrillation, and coronary artery disease can also contribute by causing structural and functional changes in the heart. Often, HFpEF arises from a combination of these risk factors rather than a single cause.
Recognizing Symptoms and Diagnostic Approaches
Individuals with preserved LV systolic function often experience symptoms. Shortness of breath, particularly during physical exertion or when lying flat (orthopnea), is a frequent complaint. Many also report fatigue and a reduced ability to engage in physical activities. Swelling in the legs, known as peripheral edema, can also occur.
Diagnosing HFpEF requires a comprehensive evaluation, as its symptoms can overlap with other conditions. A physical examination may reveal signs of fluid overload, such as jugular venous distention or crackles in the lungs. Echocardiography is a primary diagnostic tool, allowing healthcare providers to assess the heart’s structure and function, including left ventricular ejection fraction and evidence of impaired relaxation or increased filling pressures. Blood tests, specifically measuring natriuretic peptides like BNP or NT-proBNP, also support the diagnosis, as elevated levels can indicate heart strain. In some cases, exercise stress testing or invasive hemodynamic assessment may be performed to reveal elevated heart pressures that only become apparent during physical activity.
Treatment and Lifestyle Management
Managing preserved LV systolic function involves a multifaceted approach aimed at alleviating symptoms, improving functional capacity, and preventing hospitalizations. A primary strategy involves addressing and controlling the underlying conditions that contribute to HFpEF. This includes rigorous management of high blood pressure, diabetes, and other associated health issues. Diuretic medications are commonly prescribed to reduce fluid retention and ease symptoms like shortness of breath and swelling.
Newer medications, such as sodium-glucose cotransporter-2 (SGLT2) inhibitors, have shown promise in improving outcomes for individuals with HFpEF. Angiotensin receptor-neprilysin inhibitors (ARNIs) and mineralocorticoid receptor antagonists (MRAs) may also be considered.
Alongside medical therapies, lifestyle modifications play a significant role. Regular physical activity, tailored to individual abilities, can improve exercise tolerance and overall well-being. Adopting a low-sodium diet helps minimize fluid retention. Weight management, through dietary changes and exercise, is also beneficial, particularly for those who are obese. Smoking cessation is recommended to improve cardiovascular health.