The extent of the infarction depends on the size of the occluded vessel. The larger the vessel, the worse the consequences. In the case of a large infarction, the strain on the heart can be so great that the circulation collapses. Then there is an acute danger to life, just as there is if the infarction is accompanied by a cardiac arrhythmia (ventricular fibrillation). If a heart attack is suspected, the emergency services must therefore be called immediately!
In Germany alone, around 300,000 people suffer a heart attack every year. Unfortunately, the mortality rate is very high - almost half of all patients die before reaching the hospital. This makes myocardial infarction one of the most common causes of death in our country. The risk of a heart attack is higher in men than in women. This is mainly due to the fact that women have a reduced risk until the menopause thanks to female sex hormones. However, due to the non-specific symptoms and the fact that the rescue chain is triggered later, the death rate is higher in women.
The heart muscle, which pumps the blood through the human body, is supplied with oxygen and nutrients by the two coronary arteries. If deposits, so-called plaques, form in the arteries, the blood flow is impaired. These deposits of connective tissue, blood lipids and blood clots build up over many years. There is a risk of the plaque surface breaking open and causing a blood clot, which acutely blocks the coronary artery and causes a heart attack.
Doctors refer to vascular calcification as arteriosclerosis, the main cause of a heart attack. The disease itself, i.e. the narrowing (stenosis) of the coronary arteries, is referred to as coronary heart disease (CHD). Heart attack patients are often already being treated for angina pectoris (chest tightness), a condition that accompanies coronary heart disease. In addition to arteriosclerosis, other causes can also trigger a heart attack. Even in healthy coronary arteries, local formation(thrombosis) or the spread (embolism) of a blood clot can lead to a heart attack. Another possibility is vascular spasm (vasospasm).
Heart attacks cannot be completely prevented. However, there are some risk factors that promote heart disease:
- Unhealthy diet - foods with a high energy density and high fat content lead to obesity
- High cholesterol levels - the formation of plaque is favored
- Increased blood pressure - hypertension damages the inner walls of blood vessels
- Lack of exercise - sport lowers blood pressure and improves cholesterol levels
- Smoking - cigarettes, pipes and cigars promote the development of plaque
- Diabetes mellitus - elevated blood sugar levels damage the inner walls of the arteries
- Predisposition - the risk increases with diseases within the family
- Gender - men fall ill more often than women
- Age - increased risk for men aged 45 and over and women aged 55 and over
With a heart attack, every minute counts, so it is worth knowing the symptoms . It is important to know that the signs differ between men and women. The classic signs of a heart attack are
- Severe, sometimes burning or pressing pain in the chest that lasts longer than five minutes
- The pain may radiate to the shoulder, arm, upper abdomen or lower jaw
- Significantly more severe pain than during an angina attack, taking the nitrate medication has no effect
- Strong feeling of restlessness up to fear of death
- Pallor and cold sweats
- Shortness of breath and dizziness to the point of unconsciousness
- Nausea and vomiting
Only around a third of women suffer from the typical chest pain during a heart attack. Instead, women report a feeling of tightness in the chest, shortness of breath, nausea and vomiting or pain in the upper abdomen. Around half of all patients complain of sleep disturbances in the run-up to the infarction.
Myocardial infarction is not always accompanied by symptoms. Silent or silent myocardial infarction is only diagnosed after days or even years and often affects people with diabetes.
The most important examination procedure in the diagnosis of a heart attack is the ECG. Thanks to the electrocardiogram, the location and extent of the infarction can be determined. During the examination, special electrodes are attached to the patient's chest, which the doctor, usually a cardiologist, can use to check the heartbeat and electrical excitation in the heart muscle. This determines whether cardiac arrhythmia is present.
The results also provide information as to whether the heart attack is acute or has occurred some time ago. As infarctions cannot always be detected immediately on the ECG, several tests are carried out at intervals of a few hours if a myocardial infarction is suspected.
If no typical changes are visible on the ECG, an ultrasound examination can provide further information about the condition of the heart. A blood test is also arranged. The dying heart muscle cells release enzymes, which can also be detected in the blood in increased concentrations with a slight delay.
A cardiac catheterization provides a very precise diagnosis. A flexible plastic tube is inserted via the leg artery to the heart. A contrast agent is injected via the catheter, which makes the heart and vascular structures visible on the X-ray monitor. With this method, a blocked vessel can not only be detected, but also reopened at the same time.
Heart attack patients are taken to the intensive care unit. There, the declared aim is to reopen the blocked coronary artery. There are various procedures for this:
- Lysis therapy - The blood clot is dissolved using lysis medication. However, the medication not only affects the heart, but the entire body. Serious bleeding can be the result. Shortly after the heart attack, the chances of the coronary vessel reopening are greatest. However, this treatment method is hardly successful 12 hours after the heart attack.
- PCTA - Percutaneous transluminal coronary angioplasty is performed using a cardiac catheter. A balloon is used to dilate the affected coronary vessel so that blood flow to the heart is restored. A stent (a small metal scaffold) is often also implanted in the vessel to prevent it from closing again.
- Bypass surgery - If the changes to the coronary arteries are particularly severe, surgical intervention may be necessary. During bypass surgery, the doctor bridges the narrowed area with the help of a vascular substitute. Doctors refer to this as arterial bypass (using part of the thoracic artery) or venous bypass (using a vein from the thigh or lower leg).
Arteriosclerosis, the most common cause of myocardial infarction, is best prevented by reducing risk factors. Quitting smoking, a healthy and balanced diet and sufficient exercise keep the heart healthy. Overweight people should definitely consider losing weight. Patients with high blood pressure, elevated cholesterol levels or diabetes mellitus are advised to ensure that they receive optimal treatment and take their prescribed medication correctly.
