Cardiogenic shock represents a form of shock caused by weakened pumping action of the heart. It is an absolute emergency that often leads to death from heart failure without immediate treatment. There are multiple causes of cardiogenic shock.
What is cardiogenic shock?
Cardiogenic shock is caused by pumping failure of the heart. As part of this disease process, the heart is no longer able to ensure the required cardiac output (HMV). Cardiac output defines the volume of blood that the heart pumps through the body within one minute. It represents the product of heart rate and stroke volume. Heart rate, in turn, refers to heartbeats per minute. The stroke volume is the amount of blood pumped into the circulation by one heartbeat. Normally, cardiac output is approximately 4.5 to 5 liters per minute. During unusual exercise, the HMV can increase fourfold. This can be caused by both the increase in heart rate and the increase in stroke volume. Cardiac output can decrease dramatically due to a variety of causes. These causes include structural heart changes, valvular defects, arrhythmias, hypertension, myocardial infarction, or stiffening of the heart walls. Cardiogenic shock is the most extreme form of decreased cardiac output. However, cardiogenic shock is only one form of shock. In addition to cardiogenic shock, there is also volume deficiency shock, septic shock, and anaphylactic shock. However, each type of shock characterizes a life-threatening condition associated with hypoxia of the internal organs. Regardless of the cause, the course of shock is always the same.
Causes
Cardiogenic shock is generally caused by failure of cardiac output. The cause is usually a previous disease of the heart. In this case, the volume of blood flowing through the body suddenly decreases. As a result, the organs are not supplied with enough oxygen. The lack of oxygen leads to increased anaerobic degradation processes. This metabolic pathway does not require oxygen to break down nutrients and endogenous substances. As a result, complete degradation does not take place. Among other things, acidic degradation products are formed. The body therefore becomes more and more acidic, further fuelling the process. This acidosis causes the arterioles to slacken and damages the blood capillaries. Fluid loss sets in, which in turn increases hypovolemia. In addition, blood stasis occurs in the hair vessels, which can lead to microthrombi. The entire process, regardless of its cause, intensifies more and more in the form of a vicious circle and is therefore also referred to as a so-called shock spiral. Cardiogenic shock can be caused by, among other things, a heart attack, generalized heart failure, bradycardia. An extreme increase in heart rate, ischemia, arterial hypertension, or valvular heart disease. However, cardiac medications such as beta blockers, as well as cytostatic drugs or antidepressants, can also cause cardiogenic shock under certain circumstances.
Symptoms, complaints, and signs
Common symptoms of shock include pallor and hypotension. In cardiogenic shock, dyspnea, chest pain, and congested neck veins are also found. Furthermore, a severely reduced pulse rate (bradycardia), ventricular fibrillation, or pulmonary edema may also occur. Difficulty breathing occurs with moist rales. Systolic blood pressure is below 90 mmHg with a cardiac index below 1.8 l/min/m². Each square meter of body surface is perfused by a maximum of 1.8 liters of blood per minute. As a result, multi-organ failure of the liver, kidney, intestine, and central nervous system may occur. Consciousness becomes cloudy. Without treatment, cardiogenic shock can be fatal.
Diagnosis and course of the disease
Shock can be diagnosed very quickly based on symptoms. However, it is more difficult to determine what form of shock is present. However, a known cardiac condition and the additional symptoms that occur, such as respiratory distress or pulmonary edema, will quickly lead the physician to the suspected diagnosis of “cardiogenic shock.” Thus, after emergency treatment of the shock, the actual treatment of the heart can begin immediately.
Complications
This shock is usually a medical emergency. If this does not result in immediate treatment, the patient may also die. Severe respiratory distress usually occurs with this shock. The patient’s resilience drops significantly and the affected person appears tired and exhausted. Likewise, there may be a decreased heart rate and the affected person may continue to lose consciousness completely. The quality of life is significantly reduced and diminished by this shock. The internal organs also often no longer function properly, so that organ failure can occur in the worst case. It is not uncommon for patients to suffer from fear of death, panic attacks or sweating. Treatment of this shock must be immediate if the patient is to survive. Surgical interventions and medication are necessary to combat the symptoms. Furthermore, however, causal treatment of this complaint is also necessary so that the underlying disease is limited and shock does not occur again. Under certain circumstances, life expectancy may be reduced. Further complications depend thereby strongly on the basic illness, so that usually no general prediction is possible.
When should you go to the doctor?
If symptoms such as shortness of breath, discomfort of the cardiovascular system or chest pain are noticed, a doctor should be consulted in any case. If the symptoms occur quite suddenly, an emergency physician must be called. Cardiogenic shock can be fatal if not treated in time. Therefore, a doctor must be consulted at the first signs. If signs of shock are noticed, medical advice is also needed. First responders should call in the emergency medical services and provide first aid measures if in doubt. Typical shock symptoms such as shortness of breath or circulatory problems should always be clarified by a physician, regardless of whether cardiogenic shock is suspected. In addition to the family physician, the internist or a cardiologist can be involved. In some circumstances, the involvement of a therapist may also be appropriate, especially if the cardiogenic shock occurred in association with an accident or fall. Children who show signs of cardiogenic shock should be taken to a pediatrician promptly.
Treatment and therapy
Cardiogenic shock is an emergency and must be treated as soon as possible. This includes percutaneous coronary intervention (PCI). Here, a left heart catheter is used to dilate constrictions. For this purpose, a balloon or a stent is inserted via a catheter. If blood clots are present, systemic fibrinolysis is performed. Fibrinolysis is an enzymatic cleavage of fibrin, which allows the thrombi to dissolve. Furthermore, emergency bypass surgery must often be performed. At the same time, anticoagulant substances are administered to prevent further formation of blood clots. Anticoagulant substances include platelet function inhibitors or thrombin inhibitors. Parallel to emergency treatment, the cardiovascular system must be stabilized. Thus, the patient should be placed in cardiac bed positioning. In cardiac bed positioning, the upper body is positioned high and the legs low. This is to reduce venous blood flow to the heart. The patient must be secured against slipping in this position. The circulatory system is additionally stabilized by vasoactive substances such as dobutamine, vasodilators or norepinephrine. Intraaortic balloon counterpulsation is also often performed. This is a balloon pump commonly used in emergency medicine that also improves oxygen delivery by improving blood flow.
Outlook and prognosis
Treatment with catheter intervention and immediate opening of occluded coronary arteries has significantly reduced acute mortality in patients with cardiogenic shock over the past 20 years. Early recognition of cardiogenic shock is critical to reducing acute mortality. If cardiogenic shock remains untreated, this leads to multiple organ failure and subsequently to the death of the patient. For the further prognosis of surviving patients of cardiogenic shock, the first period immediately after hospital discharge seems to be particularly critical.Within the first 60 days, significantly more patients with cardiogenic shock die than patients without shock. During the stay in hospital, however, the chances of survival have increased significantly in recent years. As recently as the 1980s, about 70 percent of all patients admitted to a hospital with cardiogenic shock died. Today, the figure is around 40 percent. Adequate therapy management and close cardiac monitoring can improve the short- and long-term prognosis of patients with cardiogenic shock. However, complete recovery after an extensive infarction is usually no longer expected.
Prevention
The best prevention of cardiogenic shock is prevention of atherosclerosis, which can lead to heart disease. This can be achieved by maintaining a healthy lifestyle with a balanced diet, getting plenty of exercise, and avoiding alcohol and smoking.
Follow-up
In the event of such a shock, there are usually only a few measures of aftercare available to the affected person. In this case, an emergency physician should be called quickly or a hospital should be visited directly so that the affected person does not die as a result of this shock. Furthermore, the underlying disease must be treated to prevent a recurrence of this complaint. In many cases, however, such a shock significantly reduces the life expectancy of the affected person. In general, patients with this condition should take it easy and rest. Efforts or stressful or physical activities should be refrained from in order not to put unnecessary strain on the body. Furthermore, a healthy lifestyle with a healthy diet and light sports activities can also have a positive effect on the course of the disease. After emergency treatment, the cause of the shock must first be identified. Furthermore, the underlying disease must be limited, so that no general prediction can be made here. The affected person should have his heart regularly examined and checked by a physician. Further measures of aftercare are usually not available to the affected person. In many cases, they are strongly dependent on the underlying disease.
What you can do yourself
When cardiogenic shock occurs, first aid must be given immediately. First responders should keep the victim’s upper body slightly elevated. If blood pressure is low, the supine position is recommended, because otherwise too much blood will flow to the upper body and too much stress will be placed on the already damaged pump muscle. If the patient is conscious, he should sit on the floor with his legs outstretched and support his upper body backwards with his arms. It should be noted that the affected person must not drink anything. His clothing is best loosened. Accompanying these measures, the rescue service must be called as soon as possible. If the patient is unconscious, cardiac massage or rescue breathing is indicated. After treatment, the patient must take it easy for at least three to four weeks. Lifestyle changes may also be necessary. Depending on the cause, the doctor may recommend a healthier diet, more exercise and avoiding stress. It is important to avoid stimulants in the first period after the treatment. To avoid another shock, the patient should visit the clinic regularly for check-ups.