What happens during cardiac arrest
In most cases, the heart does not stop immediately, but begins to contract chaotically: ventricular fibrillation or pulseless ventricular tachycardia occurs. In this case, the blood is not released into the vessels, the pressure drops to zero. Less common is asystole - a complete absence of electrical activity - or electromechanical dissociation, when there are impulses but no contractions. The brain tolerates the lack of blood flow for only a few minutes, so it is not the diagnosis on the spot that is important, but the immediate start of resuscitation.
- Ventricular fibrillation is the most common mechanism
- Pulseless ventricular tachycardia
- Asystole
- Electromechanical dissociation
- Cardiac arrest is not the same as a heart attack, although it is often caused by it
Causes and risk factors
The most common cause in adults is coronary heart disease, especially acute myocardial infarction and scar changes after a heart attack. In young people and athletes, cardiomyopathies, coronary artery anomalies, myocarditis and hereditary rhythm disorders come to the fore. Stopping can also be caused by severe electrolyte disturbances, overdose of drugs and drugs, electric shock, drowning, and serious injury.
- Coronary heart disease and myocardial infarction
- Heart failure with reduced ejection fraction
- Hypertrophic and dilated cardiomyopathy
- Long QT syndrome, Brugada syndrome
- Myocarditis
- Disorders of potassium and magnesium levels, poisoning
- Smoking, obesity, diabetes, high blood pressure
First aid: what to do before the ambulance arrives
Make sure the person is unresponsive and not breathing normally, and immediately call an ambulance on 103 using speakerphone. Lay the victim on a hard, flat surface, place the heel of your palm on the middle of the chest, the other hand on top and begin rhythmic pressure to a depth of about 5 cm with a frequency of approximately 100-120 per minute, completely releasing the chest between pressures. Do not interrupt the massage for more than a few seconds. If you have an automatic defibrillator nearby, turn it on and follow the voice prompts.
- Check reaction and breathing, call for help
- Call 103 without leaving the victim's side
- Start chest compressions without delay
- Rhythm - about 100-120 pressures per minute
- Use an automated external defibrillator if available
- Continue until the team arrives or signs of life appear
Examination after recovery and in people at risk
After successful resuscitation, the task of doctors is to find the cause and prevent recurrence. In the hospital, an ECG, tests for markers of myocardial damage and electrolytes, echocardiography are performed, and if a heart attack is suspected, coronary angiography is performed. For people without cardiac arrest but with syncope on exertion, palpitations, or a family history of sudden death at a young age, a cardiologist will schedule a routine evaluation.
- ECG and rhythm re-registration
- Echocardiography
- 24-hour Holter ECG monitoring
- Load test (treadmill test)
- Coronary angiography according to indications
- Blood tests: electrolytes, troponin
- Genetic testing for hereditary syndromes
Treatment of cause and prevention
Further tactics depend on what caused the stop. In case of a heart attack, blood flow in the artery is restored; in case of dangerous arrhythmias, implantation of a cardioverter-defibrillator is discussed, which recognizes fibrillation and delivers a shock. For heart failure, medications are selected that have been proven to reduce the risk of sudden death. All medications are prescribed by a doctor. General prevention - control of blood pressure, cholesterol and sugar, quitting smoking, feasible regular activity and timely examination in case of fainting.
- Treatment of coronary heart disease, revascularization
- Implantable cardioverter-defibrillator according to indications
- Continuous therapy for heart failure
- Control blood pressure, cholesterol and glucose
- Quitting smoking and drinking energy drinks in large quantities
- Examination before starting intensive training
- Teaching loved ones cardiopulmonary resuscitation skills