What Are Acute and Chronic Heart Failure?

Heart failure (HF) can develop suddenly or slowly. This is called the time of onset. The way heart failure develops affects the way it is treated and often impacts the outcome.

Acute heart failure

People with acute heart failure (AHF) have no previous signs and symptoms of heart failure. The rapid onset of new or worsening signs and symptoms typically requires immediate intervention. It is less prevalent than heart failure that develops over time.

Causes and symptoms of acute heart failure

The most common cause of acute heart failure is a heart attack (also called myocardial infarction or MI). This is caused by blockages in the arteries supplying blood to the heart muscle. Other causes include viruses, severe infections, allergic reactions, blood clots in the lungs, certain medications, or an illness that can attack the heart muscle.¹

Shortness of breath (dyspnea) is the most common symptom of AHF. Acute heart failure can also present with symptoms of rapid swelling and fluid retention characterized by sudden weight gain, up to several pounds in a 24-hr period. Coughing, wheezing, difficulty laying flat to sleep, as well as an irregular heartbeat can also be symptoms. In some cases, it is related to pre-existing cardiomyopathy. AHF often requires unexpected hospital admission. This tends to have a poor prognosis, with a high risk of readmission and death post-discharge.¹ Seek emergency medical treatment if sudden or painful symptoms develop.

Diagnosis and treatment of acute heart failure

In order to diagnose acute heart failure, a physician will take a complete medical history and perform a physical exam to detect congestion and fluid build-up or abnormal heart rhythms. Blood and imaging tests are also used to diagnose the type of heart failure and to determine how severe it is.³ Treatment options include medication, surgery, and implanted medical devices as well as recommended lifestyle modifications. Managing symptoms is always a part of treating any kind of heart failure.²

Chronic heart failure

The term heart failure generally describes people with established chronic heart failure (CHF).⁴ Chronic heart failure develops slowly. It is a condition in which the heart has become weaker and has difficulty pumping enough blood through the body to supply it with oxygen.^4-5

Causes and symptoms of chronic heart failure

HF is most common in men and people over age 65. It can be caused by coronary artery disease, heart attack, high blood pressure, or other conditions that may have damaged or weakened the heart. Risk factors include older age, being overweight, and the presence of metabolic disorders like diabetes. Symptoms can include shortness of breath, fatigue during normal activities, and swelling of the feet, ankles, and abdomen.⁴ CHF is a long-term condition that can get worse over time and interferes with the heart's ability to pump blood out to the rest of the body.²

Symptoms of chronic heart failure include:²

• Shortness of breath (dyspnea) upon exertion or lying down
• Fatigue and weakness
• Swelling in the lower extremities and/or abdomen
• Rapid weight gain from fluid retention
• Irregular heartbeat (arrhythmia)
• Difficulty exercising
• Persistent cough or wheezing with white or pink blood-tinged phlegm
• Chest pain if your heart failure is caused by a heart attack

Diagnosis and treatment of chronic heart failure

The diagnosis of chronic heart failure uses the same format as when diagnosing acute heart failure. A physician will take a complete medical history and perform a physical exam to detect congestion and fluid buildup or abnormal heart rhythms. Blood and imaging tests are also used to diagnose the type of heart failure and to determine how severe it is. To determine the most appropriate treatment, heart failure is generally classified by doctors to assess the stage and functional status of HF according to the severity of their self-reported symptoms.^2,3

Chronic HF is a life-long condition that will get worse over time. It generally cannot be cured but it can be medically managed over a lifetime. Treatments may be able to improve the signs and symptoms of heart failure and help you live longer. Lifestyle changes require effort, but increasing exercise, reducing dietary sodium, managing stress, and losing weight may improve quality of life.²