If at least one coronary artery is completely closed, this is considered to be a heart attack (myocardial infarction). A blood clot which attaches itself to an arteriosclerotic constriction is generally responsible for the obstruction. A heart attack is an emergency which requires correct, urgent action. The more quickly a patient suffering a heart attack receives the correct treatment, the better their prognosis will be.
Arteriosclerosis is usually the underlying cause of a heart attack. The main risk factors for the occurrence of arteriosclerosis are smoking, high blood pressure and high cholesterol. If an already calcified coronary artery is completely closed by a blood clot, this causes a heart attack. A part of the heart muscle then no longer receives oxygen and dies quickly as a result if the circulatory disorder is not quickly remedied. Scar tissue also forms in the heart muscle after a heart attack. This can cause cardiac arrhythmias or cardiac insufficiency.
Heart attack patients often suffer from angina pectoris with temporary circulatory disorders of the heart before a heart attack. However, unlike angina pectoris, the symptoms of a heart attack are generally much stronger. Severe chest pain or a feeling of tightness in the chest, accompanied by shortness of breath, nausea, sweating and fear of death are typical symptoms of a heart attack. Doctors also call these clinical symptoms acute coronary syndrome. However, milder pain which does not improve when a patient keeps still and lasts longer than 15 minutes can already point to a heart attack. The pain also often radiates into the neck, the shoulders and the arms.
If you suspect that someone is having a heart attack, they must be immediately admitted to hospital. The diagnosis can be quickly made with an ECG examination and by determining the troponin level in the blood. Troponin is a substance which occurs if the heart muscle is damaged. If a patient has a heart attack, increased troponin levels will already be detectable in the blood soon after the event.
It is vital that blood flow is restored to the heart muscle quickly after a diagnosis has been made. There are various options available. Depending on the situation, the blood clot responsible for the infarction can be dissolved with medication (thrombolysis), or the blocked blood vessel can be opened surgically. Find out more about the surgical treatment methods using balloon dilatation, stent or bypass surgery in the chapter entitled Surgery on the Coronary Arteries.
After a heart attack, existing risk factors usually require life-long treatment to prevent further incidents. Depending on the constellation, these include antihypertensives, cholesterol-reducing medication and blood thinners.