Cardiology Internal Medicine

Heart Failure with Reduced Ejection Fraction (HFrEF)

Heart Failure With Reduced Ejection Fraction, HFrEF
Heart Failure With Reduced Ejection Fraction, HFrEF, Right Sided.

Introduction – Heart Failure with Reduced Ejection Fraction

Heart Failure with Reduced Ejection Fraction (HFrEF) is a common condition, with higher incidence and prevalence at later stages of life. The underlying cause is found in some form of injury or disease of the heart. It is estimated that about 2% of the population is affected and in individuals over 80 years the prevalence is 10%.

Heart failure has a high mortality rate, which can be reduced with adequate treatment. Sudden death is a common cause of mortality. Heart failure can debut acutely (acute heart failure), but can just as often have a slow course of onset. Registry studies show that a remarkable number of patients are not adequately diagnosed or treated according to established recommendations. In part, this may be because the symptoms can easily be mistaken for other causes or that heart failure is one of several comorbidities of the patient.


Etiology

All heart disease can cause heart failure. Heart failure can also be affected by diseases and conditions outside the heart. Toxins, drugs, and poisons can sometimes cause heart failure. It is common for patients with heart failure to have other complicating comorbidities. However, heart failure may be the condition that has the most severe prognosis, which is often not sufficiently acknowledged in care.


Common Causes – Heart Failure with Reduced Ejection Fraction

  • Ischemic heart disease, with or without underlying myocardial infarction, is by far the most common cause of heart failure (cause of 50-75% of all heart failure)
  • Hypertension (alone or with other causes)
  • Cardiac Muscle Diseases (Cardiomyopathies)
  • Valvular
  • Diabetes
  • High alcohol consumption (alcoholism)

Common causes of acute deterioration in chronic heart failure

  • Acute ischemia or heart attack
  • Poor compliance (patient has not taken his medication as prescribed)
  • Acute infection (in flu, heart failure is a common cause of death)
  • Arrhythmia (e.g. atrial fibrillation )
  • Drug and alcohol abuse
  • Anemia
  • Impaired renal function
  • Deterioration in concurrent chronic lung disease (COPD)
  • Drugs that interact with heart failure (NSAIDs) or cardiotoxic drugs (cancer treatment)

Symptoms – Heart Failure with Reduced Ejection Fraction

  • The cardinal symptom is dyspnea, which is accentuated when lying down (orthopnea) and when exerted. Paroxysmal nocturnal dyspnea is a typical heart failure symptom.
     
  • Palpitations or other chest discomfort.
     
  • Weight gain, leg swelling, and abdominal distension.
     
  • Impaired general condition.

Clinical Findings

The following list of findings exists in different constellations depending on the severity and type of heart failure. In the case of chronic heart failure treated with recommended drugs, a functional impairment may present with very discrete or non-existent clinical findings.

  • General appearance: Labored breathing, especially when lying down, cold skin, cyanosis.
     
  • Heart rate and blood pressure: Heart failure may be associated with hypertension and high blood pressure. However, more common in chronic heart failure is low and sometimes difficult measured blood pressure. Heart rate is usually elevated, the pulse is weaker than normal.
     
  • Pulmonary auscultation: Pulmonary rales, pronounced basally. The worse the pulmonary congestion, the higher up the pulmonary fields, rales can be heard. Extended expirium and rhonchi.
     
  • Heart: Tachycardia, throat swelling, neck vein stasis, left-shifted and widened ictus, murmurs due to valvular pathology, S3 heart sound.
     
  • Abdomen: Enlarged and aching liver, ascites.
     
  • Extremities: Pitting edema.

Assessment

  • Determine the diagnosis of heart failure
  • Assess the degree of heart failure
  • Determine the cause of heart failure

To determine the diagnosis of heart failure, there should be typical symptoms as well as signs of impaired heart function. In most cases, echocardiography is needed to determine the diagnosis and the cause of heart failure, systolic or diastolic dysfunction, and valvular disease.


Diagnostics (Primary Care Level)

  • ECG (arrhythmia, signs of infarction, bundle branch blocks, AV block)
  • Cardiac radiology (cardiac enlargement, pulmonary stasis, pleural fluid, pulmonary abnormalities. Also motivated by the fact that lung disease is the most common differential diagnosis of heart failure.)

Blood:

  • Electrolytes (sodium, potassium, creatinine)
  • Liver panel (ASAT, ALAT, ALP, bilirubin)
  • Glucose
  • CRP
  • CBC (Hb, LPK, TPK)
  • Hematological tests (Prothrombin, APTT)
  • Thyroid diagnostics (TSH, T3 / T4)
  • BNP or NT-proBNP, see below

Completely normal ECG and normal cardiac x-rays, as well as normal values ​​of BNP / NT-proBNP, make the diagnosis of heart failure unlikely.

Other Diagnostics (Cardiology / Medical Clinic)

  • Echocardiography (assessment of the degree of heart failure [ejection fraction] and the possibility of underlying heart disease). Echocardiography is indicated in all newly discovered cases of heart failure.
     
  • Exercise ECG testing (maximum work ability is a measure of the degree of heart failure; underlying myocardial ischemia can be evaluated).
     
  • Cardiac event recorder (arrhythmia).
     
  • Coronary angiography (ischemic heart disease).
     
  • CT angiography or cardiac scintigraphy (to exclude coronary disease)
     
  • Cardiac magnetic resonance imaging – can provide information about myocardial changes such as scars or edema, ventricular and flap functions.
     
  • Cardiac catheterization for evaluation of pressure and flow, combined with cardiac biopsy (in rare cases).

Natriuretic peptides

Natriuretic peptides are secreted from cells in the atrium and ventricles of the heart in response to rising filling pressures and stretching of tissue.

The levels of the peptides correlate well with the degree of heart failure and prognosis. Studies show that natriuretic peptides also rise in more severe heart disease of another type, for example in acute coronary syndrome, valvular disease, etc.

Today, rapid tests are available and many laboratories have set up routine methods for analyzing BNP and NT-proBNP. The interpretation of these two peptides is similar, but the reference values ​​are different (higher values ​​for NT-proBNP), so the reference values ​​of the local laboratory must be taken into account. In most cases, patients with newly discovered or worsened heart failure have values ​​of NT-proBNP exceeding 1000 ng / L. NT-proBNP values ​​are four times higher than BNP values ​​approximately.

Low values ​​strongly advise against heart failure diagnosis (eg NT-proBNP <125 ng / L). Medium values ​​lead to heart failure suspicion. Levels of natriuretic peptides increase with age, renal impairment, atrial fibrillation and in women. Obesity can give lower values. BNP and NT-proBNP can be valuable in emergency situations for diagnosis of unclear dyspnea. Many units use the peptides as monitoring during chronic disease course.

Further Reading