Chronic heart failure

chronic heart failureChronic heart failure (also known as cardiac failure or congestive heart failure) is a condition characterized by an abnormal heart function – insufficient to pump the blood effectively.

Description
The heart is the major part of the circulatory system which pumps blood. Heart failure is a life-threatening condition when the heart is unable to pump blood effectively. This leads to the stasis of the blood in the pulmonary and systemic circulation and  impairment of the blood supply to the brain, muscles and other internal organs.
It was estimated that about  15-23 million of people in the world suffer from chronic heart failure.



Causes and risk factors

  • Arterial hypertension;
  • Diabetes mellitus;
  • Coronary artery disease and  myocardial infarction;
  • Left ventricle hypertrophy;
  • Heart defects;
  • Cardiomyopathy(dilated, hypertrophic, restrictive);
  • Myocarditis and pericarditis;
  • Pulmonary hypertension;
  • Valvular heart disease;
  • Alcohol abuse;
  • Anemia;
  • Liver cirrhosis;
  • Thyrotoxicosis;
  • Beri-beri;
  • Severe smoking is associated with cardiovascular diseases.

 

Symptoms

Heart failure is characterized by the progressive course of the disease.
In the beginning ankles  and legs appear swollen, usually in the evening (peripheral edema). Edema occurs in the larger areas and become permanent as worsens the dysfunction of the heart due to the systemic congestion (anasarca may develop).
Shortness of breath/dyspnea is the most common and the first symptom of the heart failure. Initially shortness of breath occurs due to significant physical activity causing decreased exercise tolerance. As the disease progresses,  it occurs during walking and may be present at rest at late stages of the disease.
During the night a person may wake up because of the shortness of breath. A person should sit up or stay for about 30-40 minutes to relieve the symptoms. This condition is called paroxysmal nocturnal dyspnea and occurs due to the inability of the heart to pump blood when the body is in the recumbent position. The increased blood flow to the heart leads to the pulmonary congestion and, as a result, dyspnea.
Orthopnea is similar to paroxysmal nocturnal dyspnea, although occurs not only during the night and is associated with permanent  increased pulmonary pressure. Because of the same reason a person may experience coughing on exertion or at night. The crackles or crepitaions may be heard in the lungs. These sounds  are suggestive of pulmonary edema. Heart murmurs indicate the possibility of valvular heart disease as the underlying condition.
Another common and early symptom of the disease is nocturia – often voiding at night. When the blood supply to the kidneys is impaired oliguria (low urine output) develops.  
Systemic congestion causes abdominal pain and distention, dizziness, sometimes vomiting, constipation and diarrhea. Later occurs ascites – the accumulation of the fluid in the abdomen. Fluid may also accumulate in the chest (pleural effusion, hydrothorax). The liver appears enlarged (hepatomegaly).
Impaired blood supply to the muscles causes muscular atrophy and weakness.  
Decreased blood supply to the brain causes cerebral symptoms such as confusion, memory impairment, anxiety, headaches, insomnia and nightmares.

Leafy Greens and Whole Grains Help Lower the Risk of Heart Failure

Classification

High-output or low-output Depending on the heart output
Forward or backward Forward failure is characterized by the symptoms caused by low output, including hypotension; whereas in backward failure pulmonary venous congestion is seen
Right-sided or left-sided Depending on the dysfunction of the right or left heart chambers
Diastolic or systolic Based on the failure of the heart to relax normally (diastolic dysfunction) or contract effectively (systolic dysfunction)

 

New York Heart Association Functional Classification for Congestive Heart Failure

Class Description
I Unlimited ordinary physical activity
II Physical activity slightly limited due to fatigue, pain in the chest, shortness of breath etc.
III Physical activity greatly limited. Even minor activity causes dyspnea, chest pain, fatigue etc.
IV Any physical activity causes discomfort, the symptoms present even at rest.

 

Cardiovascular disease risk test

Cardiovascular disease risk test

Diagnosis
The diagnosis is made based on the following examinations:

  • Blood test;
  • Urine test helps to estimate the function of the kidneys;
  • ECG helps to assess the heart rhythm and rate, verify the conduction problems, ischemia of the heart muscle and the signs of the infarction;
  • EchoCG helps to verify the underlying condition and estimate the heart function and to determine the stroke volume, the end-diastolic volume, the ejection fraction (EF) (low EF is characteristic for systolic heart failure, whereas in diastolic heart failure the EF remain normal);
  • Chest X-ray to diagnose pulmonary edema;
  • Coronary angiography may be performed to imagine the blocked vessel  and may be used to restore the blood supply to the myocardium;
  • Endomyocardial biopsy is helpful to make a diagnosis of cardiomyopathy, myocarditis;

 

Treatment
Chronic heart failure requires non-pharmacological, pharmacological and invasive treatment.
Non-pharmacological treatment includes lifestyle changes: weight loss if possible or at least weight control, regular physical activity, well-balanced diet with low lipid intake, sodium and fluid (to 1.5 L per day) restriction. A person with chronic heart failure should be strongly recommended to quit smoking and stop drinking alcohol.
Invasive treatment of chronic heart failure includes:

  • Revascularization of the myocardium – the repair of the blood supply to the heart muscle by the means of coronary bypass surgery or coronary stent implantation.
  • Heart valve repair or replacement when the heart failure is caused by the valvular heart disease.
  • Pacemakers and implantable cardioverter-defibrillators (ICDs) are required to maintain the heart rhythm and the heart muscle contractions.
  • Left Ventricular Assist Device (artificial heart) is used temporally before the transplantation of the heart.
  • Heart transplantation is necessary when the pharmacological treatment fails to maintain the heart function.


Applicable medicines

  • Angiotensin-converting enzyme inhibitors (ACE inhibitors) – benazepril, captopril, enalapril, lisinopril etc.
  • Angiotension receptor blockers (ARBs) – valsartan, losartan etc.
  • Beta-blockers –atenolol, bisoprolol, metoprolol, nebivolol, propranolol etc.
  • Diuretics –  thiazide diuretics (indapamide, hydrochlorothiazide), loop diuretics (furosemide, torsemide),  potassium-sparing diuretics (triamterene, spironolactone).
  • Cardiac glycosides – digoxin.
  • Hydralazine and nitrates – nitroglycerin, isosorbide mononitrate etc.
  • Anticoagulants – warfarin, heparin etc.
  • Statins – simvastatin, atorvastatin etc.