heart failure heart failure heart failure (hf), also known as congestive heart failure (chf), is a syndrome, a group of signs and symptoms, caused by an impairment of the heart's blood pumping function. symptoms typically include shortness of breath, excessive fatigue, and leg swelling. the shortness of breath may occur with exertion or while lying down, and may wake people up during the night. chest pain, including angina, is not usually caused by heart failure, but may occur if the heart failure was caused by a heart attack. the severity of the heart failure is mainly decided based on ejection fraction and also measured by the severity of symptoms . other conditions that may have symptoms similar to heart failure include obesity, kidney failure, liver disease, anemia, and thyroid disease. heart failureother namescongestive heart failure (chf), congestive cardiac failure (ccf)a man with congestive heart failure and marked jugular venous distension. external jugular vein marked by an arrow.specialtycardiologysymptomsshortness of breath, exhaustion, swollen legsdurationlifetimecausesheart attack, high blood pressure, abnormal heart rhythm, excessive alcohol use, infection, heart damagerisk factorssmoking, sedentary lifestyle, exposure to second-hand smokediagnostic methodechocardiogramdifferential diagnosiskidney failure, thyroid disease, liver disease, anemia, obesitymedicationdiuretics, cardiac medicationsfrequency40 million (2015), 1–2% of adults (developed countries)deaths35% risk of death in first year common causes of heart failure include coronary artery disease, heart attack, high blood pressure, atrial fibrillation, valvular heart disease, excessive alcohol consumption, infection, and cardiomyopathy. these cause heart failure by altering the structure or the function of the heart or in some cases both. there are different types of heart failure: right-sided heart failure, which affects the right heart, left-sided heart failure, which affects the left heart, and biventricular heart failure, which affects both sides of the heart. left-sided heart failure may be present with a reduced ejection fraction or with a preserved ejection fraction. heart failure is not the same as cardiac arrest, in which blood flow stops completely due to the failure of the heart to pump. diagnosis is based on symptoms, physical findings, and echocardiography. blood tests, and a chest x-ray may be useful to determine the underlying cause. treatment depends on severity and case. for people with chronic, stable, mild heart failure, treatment usually consists of lifestyle changes, such as not smoking, physical exercise, and dietary changes, as well as medications. in heart failure due to left ventricular dysfunction, angiotensin-converting-enzyme inhibitors, angiotensin receptor blockers, or angiotensin receptor-neprilysin inhibitors, along with beta blockers, mineralocorticoid receptor antagonists and sglt2 inhibitors are recommended. diuretics may also be prescribed to prevent fluid retention and the resulting shortness of breath. depending on the case, an implanted device such as a pacemaker or implantable cardiac defibrillator may sometimes be recommended. in some moderate or more severe cases, cardiac resynchronization therapy (crt) or cardiac contractility modulation may be beneficial. in severe disease that persists despite all other measures, a cardiac assist device ventricular assist device, or, occasionally, heart transplantation may be recommended. heart failure is a common, costly, and potentially fatal condition, and is the leading cause of hospitalization and readmission in older adults. heart failure often leads to more drastic health impairments than failure of other, similarly complex organs such as the kidneys or liver. in 2015, it affected about 40 million people worldwide. overall, heart failure affects about 2% of adults, and more than 10% of those over the age of 70. rates are predicted to increase. the risk of death in the first year after diagnosis is about 35%, while the risk of death in the second year is less than 10% in those still alive. the risk of death is comparable to that of some cancers. in the united kingdom, the disease is the reason for 5% of emergency hospital admissions. heart failure has been known since ancient times, it is mentioned in the ebers papyrus around 1550 bce. definition heart failure is not a disease but a syndrome – a combination of signs and symptoms – caused by the failure of the heart to pump blood to support the circulatory system at rest or during activity.: 3612 it develops when the heart fails to properly fill with blood during diastole, resulting in a decrease in intracardiac pressures or in ejection during systole, reducing cardiac output to the rest of the body.: 3612 : e272 the filling failure and high intracardiac pressure can lead to fluid accumulation in the veins and tissue. this manifests as water retention and swelling due to fluid accumulation (edema) called congestion. impaired ejection can lead to inadequate blood flow to the body tissues, resulting in ischemia. signs and symptoms signs and symptoms of severe heart failure congestive heart failure is a pathophysiological condition in which the heart's output is insufficient to meet the needs of the body and lungs. the term "congestive heart failure" is often used because one of the most common symptoms is congestion or fluid accumulation in the tissues and veins of the lungs or other parts of a person's body. congestion manifests itself particularly in the form of fluid accumulation and swelling (edema), in the form of peripheral edema (causing swollen limbs and feet) and pulmonary edema (causing difficulty breathing) and ascites (swollen abdomen). symptoms of heart failure are traditionally divided into left-sided and right-sided because the left and right ventricles supply different parts of the circulation. in biventricular heart failure, both sides of the heart are affected. left-sided heart failure is the more common. left-sided failure the left side of the heart takes oxygen-rich blood from the lungs and pumps it to the rest of the circulatory system in the body, except for the pulmonary circulation). failure of the left side of the heart causes blood to back up into the lungs, causing breathing difficulties and fatigue due to an insufficient supply of oxygenated blood. common respiratory signs include increased respitatory rate and labored breathing (nonspecific signs of shortness of breath). rales or crackles heard initially in the lung bases and when severe in all lung fields indicate the development of pulmonary edema (fluid in the alveoli). cyanosis, indicates deficiency of oxygen in the blood, is a late sign of extremely severe pulmonary edema. other signs of left ventricular failure include a laterally displaced apex beat (which occurs when the heart is enlarged) and a gallop rhythm (additional heart sounds), which may be heard as a sign of increased blood flow or increased intracardiac pressure. heart murmurs may indicate the presence of valvular heart disease, either as a cause (e.g., aortic stenosis) or as a consequence (e.g., mitral regurgitation) of heart failure. reverse insufficiency of the left ventricle causes congestion in the blood vessels of the lungs, so that symptoms are predominantly respiratory. reverse insufficiency can be divided into the failure of the left atrium, the left ventricle, or both within the left circuit. patients will experience shortness of breath (dyspnea) on exertion and, in severe cases, dyspnea at rest. increasing breathlessness while lying down, called orthopnea, also occurs. it can be measured by the number of pillows required to lie comfortably, with extreme cases of orthopnea forcing the patient to sleep sitting up. another symptom of heart failure is paroxysmal nocturnal dyspnea: a sudden nocturnal attack of severe shortness of breath, usually occurring several hours after falling asleep. there may be "cardiac asthma" or wheezing. impaired left ventricular forward function can lead to symptoms of poor systemic perfusion such as dizziness, confusion, and cool extremities at rest. right-sided failure severe peripheral pitting edema right-sided heart failure is often caused by pulmonary heart disease (cor pulmonale), which is typically caused by issues with pulmonary circulation such as pulmonary hypertension or pulmonic stenosis. physical examination may reveal pitting peripheral edema, ascites, liver enlargement, and spleen enlargement. jugular venous pressure is frequently assessed as a marker of fluid status, which can be accentuated by testing hepatojugular reflux. if the right ventricular pressure is increased, a parasternal heave which causes the compensatory increase in contraction strength may be present. backward failure of the right ventricle leads to congestion of systemic capillaries. this generates excess fluid accumulation in the body. this causes swelling under the skin (peripheral edema or anasarca) and usually affects the dependent parts of the body first, causing foot and ankle swelling in people who are standing up and sacral edema in people who are predominantly lying down. nocturia (frequent night-time urination) may occur when fluid from the legs is returned to the bloodstream while lying down at night. in progressively severe cases, ascites (fluid accumulation in the abdominal cavity causing swelling) and liver enlargement may develop. significant liver congestion may result in impaired liver function (congestive hepatopathy), jaundice, and coagulopathy (problems of decreased or increased blood clotting). biventricular failure dullness of the lung fields when percussed and reduced breath sounds at the base of the lungs may suggest the development of a pleural effusion (fluid collection between the lung and the chest wall). though it can occur in isolated left- or right-sided heart failure, it is more common in biventricular failure because pleural veins drain into both the systemic and pulmonary venous systems. when unilateral, effusions are often right-sided. if a person with a failure of one ventricle lives long enough, it will tend to progress to failure of both ventricles. for example, left ventricular failure allows pulmonary edema and pulmonary hypertension to occur, which increase stress on the right ventricle. though still harmful, right ventricular failure is not as deleterious to the left side. causes since heart failure is a syndrome and not a disease, establishing the underlying cause is vital to diagnosis and treatment. in heart failure, the structure or the function of the heart or in some cases both are altered.: 3612 heart failure is the potential end stage of all heart diseases. common causes of heart failure include coronary artery disease, including a previous myocardial infarction (heart attack), high blood pressure, atrial fibrillation, valvular heart disease, excess alcohol use, infection, and cardiomyopathy of an unknown cause.: e279 : table 5 in addition, viral infections of the heart can lead to inflammation of the muscular layer of the heart and subsequently contribute to the development of heart failure. genetic predisposition plays an important role. if more than one cause is present, progression is more likely and prognosis is worse. heart damage can predispose a person to develop heart failure later in life and has many causes including systemic viral infections (e.g., hiv), chemotherapeutic agents such as daunorubicin, cyclophosphamide, trastuzumab and substance use disorders of substances such as alcohol, cocaine, and methamphetamine. an uncommon cause is exposure to certain toxins such as lead and cobalt. additionally, infiltrative disorders such as amyloidosis and connective tissue diseases such as systemic lupus erythematosus have similar consequences. obstructive sleep apnea (a condition of sleep wherein disordered breathing overlaps with obesity, hypertension, and/or diabetes) is regarded as an independent cause of heart failure. recent reports from clinical trials have also linked variation in blood pressure to heart failure and cardiac changes that may give rise to heart failure. high-output heart failure high-output heart failure happens when the amount of blood pumped out is more than typical and the heart is unable to keep up. this can occur in overload situations such as blood or serum infusions, kidney diseases, chronic severe anemia, beriberi (vitamin b1/thiamine deficiency), hyperthyroidism, cirrhosis, paget's disease, multiple myeloma, arteriovenous fistulae, or arteriovenous malformations. acute decompensation main article: acute decompensated heart failure kerley b lines in radiograph of acute cardiac decompensation. the short, horizontal lines can be found everywhere in the right lung. chronic stable heart failure may easily decompensate. this most commonly results from a concurrent illness (such as myocardial infarction (a heart attack) or pneumonia), abnormal heart rhythms, uncontrolled hypertension, or a person's failure to maintain a fluid restriction, diet, or medication. other factors that may worsen chf include: anemia, hyperthyroidism, excessive fluid or salt intake, and medication such as nsaids and thiazolidinediones. nsaids increase the risk twofold. medications a number of medications may cause or worsen the disease. this includes nsaids, cox-2 inhibitors, a number of anesthetic agents such as ketamine, thiazolidinediones, some cancer medications, several antiarrhythmic medications, pregabalin, alpha-2 adrenergic receptor agonists, minoxidil, itraconazole, cilostazol, anagrelide, stimulants (e.g., methylphenidate), tricyclic antidepressants, lithium, antipsychotics, dopamine agonists, tnf inhibitors, calcium channel blockers (especially verapamil and diltiazem), salbutamol, and tamsulosin. by