SIGNS AND SYMPTOMS

Intense and prolonged thoracic pain, felt as an intense pressure that can be extended (irradiation) to arms and shoulders, mainly the left ones, to the back, and even to teeth and jaw.

• The pain is described as a giant fist twisting the heart. It is similar to that provoked by angina pectoris (angina of the chest), but more prolonged and non respondent to nitroglycerin placed under the tongue.
• Pain is sometimes felt in a different way, or it doesn’t follow a fixed pattern, especially in the elderly and diabetics, who may feel it as a prolonged pain in the upper part of the abdomen that can be attributed to indigestion.

Difficulty in breathing.

Dizziness. The only symptom at 10%.

Others: Vomiting, nausea, fainting and excessive sweat can occur.

Unstable angina antecedents: Frequent attacks of Angina Pectoris not linked to physical activity.

An infarction is a tissue area that has died due to lack of oxygen.

The myocardium, or heart muscle, can suffer an infarction in the presence of an advanced coronary disease

The blood vessels corona which feed oxygen and nutrients to the actual heart muscle (“coronary” vessels) can develop atheroma plaque (see atherosclerosis), which compromises in greater or lesser degree, the flow of oxygen and nutrients to the actual heart, producing effects that vary from a angina pectoris (when the interruption of blood flow to the heart is temporary) to a myocardial infarction (which is permanent and irreversible).

The presence of atherosclerosis in a certain vessel provokes narrowing in that vessel which facilitates the development of a thrombus, a clot of platelets, coagulation proteins and cellular waste, that ends obstructing the vessel. An embolism is a thrombus that travels in the bloodstream until it reaches a small vessel where it is lodged as an embolus. Thrombosis and embolism are, therefore, equivalent terms.

A myocardial infarction is by definition a medical emergency. If you believe you may be having one or you are in the presence of someone who may be having it, look for immediate medical attention. Delays are serious mistakes that account for thousands of deaths every year.

DIAGNOSIS

• ECG. If a person shows symptoms associated with an infarction, an ECG will be immediately performed, even while in the ambulance that carries him/her. In fact, he/she will be connected to an ECG monitor during all his/her stay at the Hospital, at least if he/she is admitted to the ward dedicated to patients with serious heart diseases, or Coronary Unit.
• Analysis. They include the determination of some enzymes that increase in volume in the bloodstream when the heart tissue is damaged.
• Isotopic studies or heart catheterization (coronagraphy). They are introduced when the acute phase is over.
  In any case, you will be under observation for several days and will be allowed to gradually increase your physical activity. The admission time to the Hospital is very variable, but generally is from 7 to 14 days.

PROGNOSIS AND COMPLICATIONS

If the infarction area is small and doesn’t compromise the bio-electric system that controls heartbeat, the chances of surviving an infarction are high. However, one out of three persons who suffer an infarction die before they can get medical attention (sudden death). A few years ago, statistics were even worse (an early death for every two infarctions). This improvement in expectations is linked to the advancement in cardiopulmonary resuscitacion (CPR), in special diagnosis tests and in emergency attention, including medicalized ambulances, and coronary units.

Because of frequent sudden deaths, the cardiopulmonary resuscitation techniques must be applied as soon as possible, to any person going through a heart attack. The majority of those still living two hours after the attack, will survive.

However, there are some possible complications:

Heart Arrhythmia

There is a bio-electric system that controls the heart beats. If it is damaged during the infarction, serious arrhythmias may appear, like the one called ventricular fibrillation, when ventricles contract in a fast, uncoordinated and inefficient way, just like a “bag of worms”, and from blood pumping effects, the heart stops.

In some other persons, there may appear slow arrhythmias, that is, the heartbeat is too slow for the right function of the heart. This may require the temporary or permanent implantation of an artificial pacemaker

Heart Insufficiency

When the infarction area is extensive, the rest of the heart may be insufficient to perform the pumping work.

Death

In one out of four persons who suffer sudden deaths, there were no previous signs of heart failure. By far, the most frequent cause of sudden death by infarction is ventricular fibrillation.

TREATMENT

• Ask for help and seek immediate medical attention. Don’t try to drive yourself to a Hospital.
• Oxygen. It can be the first measure taken at the Hospital or in the ambulance.
• Analgesics (medicines against pain). If thoracic pain persists and becomes unbearable, morphine or similar medicines can be administered.
• Thrombolytics. They are drugs used to dissolve the clot that prevents the blood from flowing. Substances like streptokinase or “tissue plasminogen activator” are administered either in the vein or directly on the clot with a catheter (a long and flexible tube).
• Nitrates. Nitroglycerin derivatives allay the heart’s work and the need for oxygen. In angina pectoris they’re taken under the tongue or also in spray. They can also be taken in prolonged action pills or applied in slow release patches on the skin. During the acute phase of a heart attack, they are usually administered intravenously.
• Beta blockers. They act by blocking many adrenaline effects in the body, particularly the stimulating effects on the heart. As a result, the heart beats more slowly and with less intensity, and therefore needing less oxygen. They also reduce arterial tension.
• Digitalis. Drugs derived from digitalis, like digoxin, act by stimulating the heart so that it pumps more blood. This is particularly important, especially if the heart attack produces heart insufficiency.
• The calcium antagonist drugs or calcium channel blockers prevent the passage of calcium into the myocardioum cells. This reduces the tendency of coronary arteries to narrow, and the load of heart work, which in turn reduces the need for oxygen. They also reduce arterial tension. They aren’t usually used during the acute phase of a heart attack, but just immediately after.