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5.9.2. Heart disease

Heart disease

Some of the most important heart diseases are:

Myocardial infarction

heart attack occurs when one of the coronary arteries that supply the heart becomes blocked with a clot or an atheroma plaque that prevents nutrients and oxygen from reaching the cells, causing part of the heart muscle to die (necrosis). If the affected area is very large, death occurs.

The person who is having a heart attack feels strong pain in the chest that spreads to the side and left side and other parts of the body.

Angina pectoris

The angina is caused by lack of oxygen in the myocardium by a plaque in the arteries coronary and manifested by chest pain and tightness behind the sternum.

It differs from myocardial infarction in that, although it also causes pain in the chest, necrosis of the muscle does not occur.

There are two types of angina pectoris:

  • Stable angina: it is the most frequent, and it occurs when exercising (lifting weight, doing sports, sexual activity) or emotional stress, lasts a few minutes and is relieved with rest or medication.
  • Unstable angina: it can appear at rest, causes more pain, lasts longer and is not relieved by rest or medication. It is more serious, and can precede a heart attack.

Heart failure

The heart failure occurs when the heart does not pump whole blood to the organs needed. As there is not enough blood supply, some of the symptoms that appear are the sensation of shortness of breath, fatigue, weakness and accumulation of fluids in the tissues (edema).


The cardiac arrhythmia is altered heart rate of the heart. This rhythm is controlled by nodules located on the wall of the heart, which through electrical impulses cause the heart to contract and dilate.

If for some reason these nodules change their rhythm, the blood has more trouble reaching the organs efficiently. The use of a pacemaker allows you to regulate and maintain your heart rate at all times.

Some of the most common arrhythmias are:

  • Tachycardia : it is an acceleration of the heart rate.
  • Bradycardia : is the deceleration of the heart rate.

Curiosity: Beethoven and cardiac arrhythmia.

Heart murmur

The heart murmur is an abnormal sound that is perceived with auscultation (using the stethoscope ) produced by the alteration of a heart valve.

Video: Heart murmur.



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