heart failure

Heart failure develops when the heart, via an abnormality of cardiac function (detectable or not), fails to pump blood at a rate commensurate with the requirements of the metabolizing tissues or is able to do so only with an elevated diastolic filling pressure.

Essential update: New heart failure guidelines published jointly by the American College of Cardiology and the American Heart Association

In June 2013, the American College of Cardiology and the American Heart Association released updated guidelines for the management of heart failure. Key recommendations include the following

·                The use of aldosterone antagonists in heart failure is strongly recommended, not only for advanced heart failure but also for mild to moderate heart failure in patients with reasonably intact renal function

·                Cardiac resynchronization therapy (CRT) may also be of benefit in mild to moderate heart failure

·                Mechanical circulatory support is an important component of treatment for advanced heart failure

·                Heart failure readmissions can be reduced by using in-hospital systems to identify heart failure patients appropriate for guideline-directed medical therapy; by developing transitional care and discharge planning that emphasizes patient education to increase treatment compliance, manage comorbid conditions, and tackle psychosocial barriers to care; by employing a multidisciplinary heart failure disease management program; and by following up every discharged patient with a phone call within 3 days and a doctor appointment within 2 weeks

Signs and symptoms

Signs and symptoms of heart failure include the following:

·                Exertional dyspnea and/or dyspnea at rest

·                Orthopnea

·                Acute pulmonary edema

·                Chest pain/pressure and palpitations

·                Tachycardia

·                Fatigue and weakness

·                Nocturia and oliguria

·                Anorexia, weight loss, nausea

·                Exophthalmos and/or visible pulsation of eyes

·                Distention of neck veins

·                Weak, rapid, and thready pulse

·                Rales, wheezing

·                S3 gallop and/or pulsus alternans

·                Increased intensity of P2 heart sound

·                Hepatojugular reflux

·                Ascites, hepatomegaly, and/or anasarca

·                Central or peripheral cyanosis, pallor

Diagnosis

Heart failure criteria, classification, and staging

The Framingham criteria for the diagnosis of heart failure consists of the concurrent presence of either 2 major criteria or 1 major and 2 minor criteria.

Major criteria include the following:

·                Paroxysmal nocturnal dyspnea

·                Weight loss of 4.5 kg in 5 days in response to treatment

·                Neck vein distention

·                Rales

·                Acute pulmonary edema

·                Hepatojugular reflux

·                S3 gallop

·                Central venous pressure greater than 16 cm water

·                Circulation time of 25 seconds

·                Radiographic cardiomegaly

·                Pulmonary edema, visceral congestion, or cardiomegaly at autopsy

Minor criteria are as follows:

·                Nocturnal cough

·                Dyspnea on ordinary exertion

·                A decrease in vital capacity by one third the maximal value recorded

·                Pleural effusion

·                Tachycardia (rate of 120 bpm)

·                Bilateral ankle edema

The New York Heart Association (NYHA) classification system categorizes heart failure on a scale of I to IV,as follows:

·                Class I: No limitation of physical activity

·                Class II: Slight limitation of physical activity

·                Class III: Marked limitation of physical activity

·                Class IV: Symptoms occur even at rest; discomfort with any physical activity

The American College of Cardiology/American Heart Association (ACC/AHA) staging system is defined by the following 4 stages

·                Stage A: High risk of heart failure but no structural heart disease or symptoms of heart failure

·                Stage B: Structural heart disease but no symptoms of heart failure

·                Stage C: Structural heart disease and symptoms of heart failure

·                Stage D: Refractory heart failure requiring specialized interventions

Testing

The following tests may be useful in the initial evaluation for suspected heart failure

·                Complete blood count (CBC)

·                Urinalysis

·                Electrolyte levels

·                Renal and liver function studies

·                Fasting blood glucose levels

·                Lipid profile

·                Thyroid stimulating hormone (TSH) levels

·                B-type natriuretic peptide levels

·                N-terminal pro-B-type natriuretic peptide

·                Electrocardiography

·                Chest radiography

·                2-dimensional (2-D) echocardiography

·                Nuclear imaging

·                Maximal exercise testing

·                Pulse oximetry or arterial blood gas

Management

Treatment includes the following:

·                Nonpharmacologic therapy: Oxygen and noninvasive positive pressure ventilation, dietary sodium and fluid restriction, physical activity as appropriate, and attention to weight gain

·                Pharmacotherapy: Diuretics, vasodilators, inotropic agents, anticoagulants, beta blockers, and digoxin

Surgical options

Surgical treatment options include the following:

·                Electrophysiologic intervention

·                Revascularization procedures

·                Valve replacement/repair

·                Ventricular restoration

·                Extracorporeal membrane oxygenation

·                Ventricular assist devices

·                Heart transplantation

·                Total artificial heart