This may be preceded by dizziness, shortness of breath, a racing heartbeat, or abnormal breathing, though some experience no warnings at all.
The symptoms of cardiac arrest come on suddenly and must be treated with cardiopulmonary resuscitation (CPR) and a defibrillator immediately
Any delay in care increases one’s risk of death.2
Some people who experience cardiac arrest have some sense that something is wrong ahead of time.
Cardiac arrest may be preceded by warning symptoms, such as:2
- Difficulty breathing or shortness of breath
- Chest pain
- Nausea and/or vomiting
- Irregular or racing heartbeat (arrhythmia)
- Lightheadedness and dizziness
- Passing out, fainting, or losing consciousness
These symptoms, of course, can be confused with those of several other conditions.
Consequently, people often do not realize that there is a problem until the actual cardiac arrest event itself is occurring.
Cardiac Arrest, Classic Symptoms
Depending on the cause, cardiac arrest can mimic other conditions.
There are three signs that, when present together, can help you distinguish a cardiac arrest from another emergency. When in doubt, seek emergency medical attention.
Early recognition of cardiac arrest symptoms, along with a fast, appropriate response, can significantly increase one’s chances of survival.3
Sudden Loss of Consciousness
The stoppage of blood flow to the brain deprives the brain of the oxygen and sugars it needs to function, resulting in the loss of consciousness (syncope).
This will occur within seconds of the heart stopping.4
Unlike other forms of syncope, in which a person may be affected suddenly or intermittently, loss of consciousness with cardiac arrest will persist until heart function and circulation are restored.
At the onset of cardiac arrest, there will often be agonizing gasping motions, labored breathing, and sometimes gurgling, moaning, or grunting.
This is known as agonal respiration, and it is present in 40% to 60% of cardiac arrest cases.
Agonal respiration is not actually breathing, per se, but rather a reflex of the brainstem as it is confronted with a cataclysmic breakdown of heart function.5
Typically, this lasts for just a few minutes before a person collapses.1
Unless heart function and respiration are restored within minutes, permanent brain damage will occur.6
The absence of a pulse is the central sign of cardiac arrest. Unfortunately, this is the symptom often missed by lay rescuers who don’t know how to find a pulse.
Don’t waste time looking for a pulse if the person has already collapsed and stopped breathing.
Even professional rescuers are being asked to spend fewer than 10 seconds checking for pulse.1
Instead, you should initiate CPR and defibrillation immediately.
Cardiac Arrest In Children
Each year, at least 20,000 infants and children go into cardiac arrest in the United States.
The American Heart Association (AHA) emphasizes the importance of administering CPR as soon as you recognize an infant or child is not breathing.
Again, you should not delay CPR to check for a pulse.7
Whereas heart disease is the leading cause of cardiac arrest in adults, children are more likely to go into cardiac arrest due to respiratory failure or asphyxia (oxygen deprivation).
Possible causes include respiratory infection, drowning, or drug overdose.8
Symptoms of impending cardiac arrest in children can begin minutes to hours before the cardiac arrest event
Some children may be asymptomatic. Others may have stomach pain, shortness of breath, dizziness, nausea, headache, or pain in their back or neck.9
According to the AHA, adequate ventilation is essential when the cause of cardiac arrest is respiratory failure.
Thus, infants and children receiving CPR should be given 20 to 30 breaths and 100 to 120 chest compressions per minute, for a ratio of two breaths per every 30 chest compressions.7
Outcomes After Cardiac Arrest
Early CPR with defibrillation is the only way to reverse cardiac arrest. Speed is of the essence if a person is to survive.
For every minute that passes without defibrillation, the chance of survival decreases by anywhere from 7% to 10%.
If emergency services arrive and administer defibrillation, survival rates are as high as 49%.3
Unfortunately, the more time that passes between the onset of cardiac arrest and treatment, the more likely it is for the cardiac arrest to lead to death.
- Panchal AR, Bartos JA, Cabañas JG, et al. Part 3: Adult basic and advanced life support: 2020 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation. 2020 Oct;142(16):s366-s468. doi:10.1161/CIR.0000000000000916
- National Heart, Lung, and Blood Institute. Sudden cardiac arrest.
- Benjamin E, Virani S, Callaway C, et al. Heart disease and stroke statistics—2018 update: A report from the American Heart Association. Circulation. 2018 Mar;137(12):e67-e-492. doi:10.1161/CIR.0000000000000558
- Shen WK, Sheldon R, Benditt D, et al. 2017 ACC/AHA/HRS guideline the evaluation and management of patients with syncope: A report of the American Heart Association Task Force on clinical practice guidelines and the Heart Rhythm Society. Circulation. 2017 Mar;136(5):e60-e122. doi:10.1161/CIR.0000000000000499
- Chan J, Rea T, Gollakota S, Sunshine JE. Contactless cardiac arrest detection using smart devices. NPJ Digital Medicine. 2019 Jun;2(1):1-8. doi:10.1038/s41746-019-0128-7
- Welbourn C, Efstathiou N. How does the length of cardiopulmonary resuscitation affect brain damage in patients surviving cardiac arrest? A systematic review. Scand J Trauma Resusc Emerg Med. 2018;26(1):77. doi:10.1186/s13049-018-0476-3
- Merchant R, Topjian A, Panchal A, et al. Part 1: Executive summary: 2020 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation. 2020 Oct;142(suppl 2):s337–s357. doi:10.1161/CIR.0000000000000918
- Atkins D. Cardiac arrest in children and young adults. Circulation. 2012 Aug;126(11):1325-1327. doi:10.1161/CIRCULATIONAHA.112.129148
- Winkel BG, Risgaard B, Sadjadieh G, Bundgaard H, Haunsø S, Tfelt-Hansen J. Sudden cardiac death in children (1-18 years): symptoms and causes of death in a nationwide setting. European Heart Journal. 2014 Apr;35(13):868-875. doi:10.1093/eurheartj/eht509
- Marijon E, Uy-Evanado A, Dumas F, et al. Warning Symptoms Are Associated With Survival From Sudden Cardiac Arrest. Ann Intern Med. 2016;164(1):23. doi:10.7326/m14-2342
- Nishiyama C, Iwami T, Kawamura T, et al. Prodromal symptoms of out-of-hospital cardiac arrests: A report from a large-scale population-based cohort study. Resuscitation. 2013;84(5):558-563. doi:10.1016/j.resuscitation.2012.10.006