Myocardial Infarction

From the main symptom, the severe chest pain, the doctor at the emergency room of a suspected three conditions, he should quickly confirm or rule. The dircetor can suffer from:
- A pulmonary embolism - a blood clot that blocks a pulmonary artery
- Myocardial infarction - a heart attack can result from a blocked coronary artery
- A bone or muscle pain - caused by exertion, trauma, stress, among others.

All these conditions have as a symptom of chest pain. Although the medical examination and patient history, can indicate a heart problem, it can rarely provide a definitive diagnosis.


Diagnostic methods - Electrocardiogram:

To confirm a diagnosis or foil, several procedures are performed. The electrocardiogram is one of the most important tools to detect a heart attack.
Some waves visible through the electrocardiograph are characteristic of a myocardial infarction. May be present in the ST segment of the electrocardiogram, for example. According to the results, it is possible to distinguish two types of myocardial infarction:
- A first type, characterized by ST segment elevation, where the heartbeat is a specific behavior and their presence confirms the diagnosis of myocardial infarction;
- A second type where there is ST-segment elevation, for which the electrocardiogram is not conclusive and other diagnostic measures are needed to complement it.


Diagnostic methods - Blood tests specific:

These tests relate to specific markers that can be used to confirm or rule out a potential diagnosis. When the heart muscle cells begin to die, the walls begin to dissolve, releasing certain proteins into the bloodstream. These proteins include troponin T and I, myoglobin and CK-MB. Troponins are more relevant to their diagnosis because they are only present in heart muscle, while myoglobin is in all muscle cells.
The dedímero is also another specific marker that, when elevated, indicates an increase in coagulant activity. Thus, levels of d-dimer below a certain level, help to exclude a pulmonary embolism with high security. The NT-proBNP, in turn, is a specific marker for heart failure, reflecting the functional state of the heart muscle after myocardial infarction.


Diagnostic methods - blood tests to non-specific:

For a complete overview of the health of the patient, the physician should also evaluate other blood parameters, such as.
- Blood gases, which provide information about the respiratory status of the patient (eg due to heart failure after a myocardial infarction);
- Electrolytes, which when elevated may cause an increased risk or a cardiac arrhythmia;
- Blood glucose, which in diabetic patients may be affected due to the stressful situation;
- Markers of kidney function, creatinine and urea, as kidney function are compromised in cardiovascular patients,
- Coagulation (PT / INR) status


What happens in a heart attack?

A myocardial infarction (or heart attack) occurs when the blood of the coronary arteries that feed the heart is blocked. This obstruction usually due to a clot that is built from atherosclerotic plaques. As a result, the heart muscle no longer receive enough oxygen and myocardial cells deprived of oxygen begin to die. Depending on the size of the blocked artery and its necrotic heart muscle, stroke is more or less severe.


Extension of the problem: occurrence and associated costs

In 2003 was admitted by hospital emergency departments 682,130 patients (68.6% of the total number of admissions), of which 7.1% (48 310) had ischemic heart disease (ICD). In 28% of these patients was made the diagnosis of myocardial infarction, which had a mortality rate of 14% and 9% in the diagnosis of DCI acute or subacute, which includes cases of unstable angina, the rate was 4%.
Moreover, the total number of patients admitted during 2003, the DCI disease (coronary atherosclerosis) was diagnosed in 3.8% of cases, the failure rate was 8.49%.
While the DCI hospitalizations were more frequent in the age group between 51 and 75 years, mortality was higher in patients aged over 76.


Treatment Options

Next to a myocardial infarction, blood flow in blocked arteries should be reinstated as soon as possible in order to avoid irreversible damage to the heart muscle. There are two therapeutic approaches to the same situation:
- Thrombolysis by administration of a drug, this time, a potent anticoagulant, is prescribed to the patient to dissolve the clot in the coronary artery
- Percutaneous coronary intervention (PCI), in which a small catheter is inserted into the artery to widen its diameter.