Congestive Heart Failure

ICD Referral Guidelines

What is Congestive Heart Failure?

Congestive heart failure (CHF) is a term used to describe the heart’s inability to pump enough blood to meet the body’s needs. Heart failure does not mean that the heart has failed completely, but rather that the heart is not strong enough to meet the body’s needs at times of stress or increased activity. The left ventricle normally receives blood from the lungs and pumps blood through the arteries to the brain, internal organs and extremities. When the left ventricle is weak the patient may experience symptoms of low cardiac output: fatigue and dizziness, and symptoms of congestion: shortness of breath on exertion, inability to lay flat and awakening at night-time with shortness of breath. If the CHF becomes severe fluid may leak into the lungs causing “pulmonary edema” and severe respiratory (breathing) difficulties. When the right ventricle fails the patient may also have symptoms of low cardiac output but also experience fluid build-up in the tissues of the body resulting in leg swelling (edema) and congestion of the internal organs.

Causes of CHF

Weakness of the left ventricle can be caused by:

  • Longstanding uncontrolled hypertension
  • Heart attacks — damage to the heart muscle due to coronary artery disease (blocked arteries)
  • Valvular heart disease — longstanding leaking or narrowing of the aortic or mitral valves
  • Viral, toxic or metabolic disturbances damaging the heart muscle. Alcohol is the commonest culprit
  • Longstanding rapid heart beating (racing) due to some form of arrhythmia
  • Congenital abnormalities e.g. ventricular septal defect (a hole between the left and right ventricles)

Weakness of the right ventricle may be caused by:

  • Failure of the left ventricle
  • High blood pressure within the lungs
  • Valvular heart disease — pulmonary valve stenosis (narrowing)/tricuspid valve leaking
  • Right ventricular infarction (heart attack) due to coronary artery disease
  • Congenital abnormalities e.g. atrial septal defect (a hole between the left and right atria)
  • Disease affecting the sac surrounding the heart (the pericardium) such as fluid accumulation (effusion) or abnormal thickening (constriction)

Is CHF dangerous?

Untreated CHF can lead to severe respiratory difficulties which can be life threatening. Fortunately there are many medications which are effective in treating the symptoms and improving the prognosis of CHF. Lifestyle modifications including proper diet and salt restriction can help reduce or eliminate the symptoms of CHF.

It is important for you to recognize the symptoms of heart failure and to alert your physician to any deterioration in your condition. If you act early on, severe heart failure and the need for hospitalization may be avoided.

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