Patients having a cardiac arrest will present with abrupt and drastic symptoms before the disease becomes eminent. In a number of cases, patients would suddenly collapse unconscious and may gain consciousness after a few minutes, or may never regain consciousness at all. It is also observable that breathing can arbitrarily stop during the cardiac event. Pulses may become faint or may not be appreciable at all especially during shock. In some cases of cardiac arrest, a number of signs may herald its onset like chest pain, fainting, dizziness, fatigue, shortness of breath, palpitation, vomiting, and weakness.

• Collapse

  Blood flow to the brain is reduced to the point that the person loses consciousness and collapses. Unless emergency treatment is provided quickly, death usually follows. Anyone is at risk There are no warning signs associated with SCA. [zoll.com]

  When someone collapses do you know what to do? There are many reasons why someone may collapse. Chief among those reasons are sudden cardiac arrest and heart attack. They are not the same thing. [plustrac.com]

  Due to the relative infrequency of in-hospital cardiac arrest, NIRS has not previously evaluated the period immediately prior to hemodynamic collapse. [ncbi.nlm.nih.gov]

  The research team searched Google and YouTube for other videos of athletes collapsing during play. [chicagotribune.com]

• Hypothermia

  Lundbye -- Hypothermia: How to Cool / Matthew W. Parker and Justin B. [worldcat.org]

  Due to costs and various health policies there is no comprehensive study in the world that has been able to guide the relevant literature on therapeutic hypothermia. [ncbi.nlm.nih.gov]

  Also known as: Hypothermia after cardiac arrest Therapeutic hypothermia after cardiac arrest is a medical treatment used to treat patients who remain unconscious after resuscitation from cardiac arrest. [oregon.providence.org]

• Weakness

  She was nauseous, vomited and had weakness of the left arm and leg. She developed a right-sided ptosis, miosis and a contralateral hemiparesis, consistent with Horner's syndrome. [rug.nl]

  A 16-year-old female patient was admitted to the emergency ward with complaints of weakness and abdominal pain, and she had four cardiac arrests during her evaluation period. She was referred to our clinic for permanent pacemaker implantation. [ncbi.nlm.nih.gov]

  Cardiac arrest often occurs without warning, causing people to suddenly: Collapse Lose consciousness Stop breathing Have no pulse Prior to collapsing, some people might experience symptoms such as: Fatigue Fainting Dizziness Chest pain Shortness of breath Weakness [utswmedicine.org]

  So a weak-stomached homicide cop looks into the possibilities of a black market for human organs, while across town a man must make a difficult decision regarding his wife, who needs a transplant... Written by Brian J. [imdb.com]

• Unconsciousness

  For those who became unconscious during the cardiac arrest, a spontaneous vascular circulation within less than 25 minutes offers a good chance of survival after the event. [symptoma.com]

  Once CPR or assisted ventilation has been established on an unconscious patient, assess the scene to determine if an opioid was ingested, inhaled or injected. [ems1.com]

  Also known as: Hypothermia after cardiac arrest Therapeutic hypothermia after cardiac arrest is a medical treatment used to treat patients who remain unconscious after resuscitation from cardiac arrest. [oregon.providence.org]

  A person in cardiac arrest will be unconscious and will stop breathing or will not be breathing normally (they may make gasping noises or may be breathing irregularly). [heartfoundation.org.au]

  Tom Petty was rushed to the hospital Sunday night after he was found unconscious, not breathing and in full cardiac arrest ... law enforcement sources tell TMZ. EMTs rushed to his Malibu home and were able to get a pulse. [tmz.com]

• Fatigue

  Dizziness, fainting, chest pain, and fatigue may sometimes herald the disease process. Diagnosis ECG is imperative in the face of a cardiac arrest. [symptoma.com]

  Lightheadedness/Fainting Fatigue Shortness of breath Nausea and/or vomiting Cold sweats Heart palpitations: when you feel like your heart is racing, pounding or fluttering. [rwjbh.org]

  […] frequent early warning signs and symptoms, which included: chest pain dyspnea “syncope” or losing consciousness unexpectedly and “palpitations” or an abnormal fluttering, thumping feeling in your chest ongoing influenza-like symptoms (e.g. malaise, fatigue [myheart.net]

  Right before cardiac arrest, some people may feel fatigued, have chest pain or shortness of breath, faint, or vomit. Often, though, cardiac arrest happens with no warning. [kidshealth.org]

  Symptoms of Cardiac Arrest Cardiac arrest often occurs without warning, causing people to suddenly: Collapse Lose consciousness Stop breathing Have no pulse Prior to collapsing, some people might experience symptoms such as: Fatigue Fainting Dizziness [utswmedicine.org]

• Pneumonia

  Overall the quality of the evidence was moderate (pneumonia) to low (hypokalaemia). [ncbi.nlm.nih.gov]

  […] provision in clear and unequivocal terms, it must be given a restrictive interpretation’. (13) en Pulmonary disorders There have been rare reports of acute diffuse infiltrative pulmonary disease of unknown aetiology such as pneumonitis, interstitial pneumonia [mt.glosbe.com]

  Another possible cause is stopping breathing, such as when a person drowns or has severe pneumonia. A person in cardiac arrest lies motionless without breathing and does not respond to questions or to stimulation, such as shaking. [msdmanuals.com]

• Snoring

  Patients with primary cardiac arrest often gasp (an abnormal snoring-like respiration) which provides adequate ventilation, but indicates a cardiac arrest. [heart.arizona.edu]

  If you have disrupted sleep, Jain suggests being screened for sleep apnea, a common, chronic disorder marked by numerous pauses in breathing while you sleep, often accompanied with loud snoring or choking sounds. [prevention.com]

  He had this snoring-type sound, which is a breathing you get when your heart is not functioning properly and you're trying to grasp for air. I tipped him back and did a sternal rub, which is when you take your knuckles and rub on your sternum. [bleacherreport.com]

• Diarrhea

  Low potassium levels can occur alongside many chronic diseases, be a side effect of a medication or be due to constant vomiting or diarrhea from an illness. [livestrong.com]

  TNF-α is associated with demyelinating peripheral neuropathy, hepatosplenomegaly, endocrine dysfunction, edema, weight loss, hypertriglyceridemia and diarrhea. [scielo.br]

• Mouth Breathing

  Conventional CPR includes both chest compressions and 'rescue breathing' such as mouth-to-mouth breathing. [ncbi.nlm.nih.gov]

  Only people with CPR training should attempt mouth-to-mouth breathing. [chicagotribune.com]

  Conventional CPR includes both chest compressions and ‘rescue breathing’ such as mouth‐to‐mouth breathing. [doi.org]

  Untrained rescuers receiving telephone advice are unable to do effective CPR combining rescue breaths and chest compressions. 14,15 Rescuers may also be more likely to start CPR if they do not have to provide mouth-to-mouth breaths. 16 Compression-only [resus.org.uk]

• Heart Disease

  According to the American Heart Association, as many as 50% of SCA victims have no prior indication of heart disease - their first symptom is cardiac arrest. [utahsafetycouncil.org]

  Congenital heart diseases: The innate abnormalities seen in congenital heart diseases can trigger a cardiac arrest as well as the scars left in the myocardium after its corrective surgery among adults. [symptoma.com]

  Read more about coronary heart disease risk factors. [web.archive.org]

  The majority of these deaths are related to ischemic heart disease, however increasingly recognized are non-ischemic causes such as cardiac channelopathies. [ncbi.nlm.nih.gov]

• Hypotension

  CASE REPORT A 65-year-old man was admitted to the Emergency Department with dysarthria, left facial ptosis, left hemiplegia, and arterial hypotension of 75/50 mmHg. [ncbi.nlm.nih.gov]

• Cyanosis

  The diagnosis of truncus arteriosus is suspected in newborns with mild cyanosis, a cardiac murmur, and pulmonary overcirculation. [doi.org]

  […] epinephrine in the field. 14, 15 On the other hand, as EMS personnel in Japan are legally prohibited from terminating resuscitation in the field (except in specific situations such as decapitation, incineration, decomposition, rigor mortis, or dependent cyanosis [jaha.ahajournals.org]

• Blurred Vision

  Common side effects of nitrates include headaches, dizziness, nausea and vomiting, blurred vision, fast heartbeat, sweating, and flushing on the face and neck. Low blood pressure and dizziness can be relieved by lying down with the legs elevated. [mountsinai.org]

• Fear

  The opposite word of Heart Failure is: Animosity, Apathy, Cowardice, Disdain, Dislike, Exterior, Fear, Hate, Hatred, Head, Indifference, Malevolence, Meanness, Mercilessness, Outside, Periphery, Surface, Ill Will and Exteriority. [urdupoint.com]

  These people fear that people who have AEDs in their homes will delay calling for help during an emergency. They're also concerned that people who have home-use AEDs will not properly maintain the devices or forget where they are. [web.archive.org]

  Images: Thinkstock Updated: July 17, 2015 Published: July, 2015 New findings may help allay fears about sports-related heart death. To continue reading this article, you must login. [health.harvard.edu]

  "This was something which I feared and something which I warned about," Oxman told CNN. "I can tell you for sure that this is something I warned about. Where there is smoke there is fire." [foxnews.com]

  His doctors believed a virus may have caused the arrhythmia O’Brien suffered; fearing a repeat event, they implanted a defibrillator. Today, O’Brien runs about 50 miles a week, follows a vegan diet, and calls both Fleitas and Getty “great” friends. [runnersworld.com]

• Dizziness

  Some people may have a racing heartbeat or feel dizzy or light-headed just before they faint. Within an hour before SCA, some people have chest pain, shortness of breath, nausea (feeling sick to the stomach), or vomiting. [web.archive.org]

  Dizziness, fainting, chest pain, and fatigue may sometimes herald the disease process. Diagnosis ECG is imperative in the face of a cardiac arrest. [symptoma.com]

  Symptoms of a Heart Attack Chest pains - uncomfortable pressure, tightness of the chest Pain in the arms, neck, jaw and shoulder Sweating Nausea Dizziness Labored breathing Heart palpitations Causes of Cardiac Arrest The immediate cause of cardiac arrest [marshfieldclinic.org]

  In this recent study men tended to have more chest pain and women tended to have more shortness of breath, lightheadedness, and dizziness. The exact reason for this difference in symptoms between men and women is not known. [myheart.net]

• Seizure

  Among the central nervous system side effects the epileptic seizures, stroke, transient and temporary leucoencephalopathy, and global amnesia are well known. [ncbi.nlm.nih.gov]

  /seizure-like activity, especially with or just after activity Dizziness or lightheadedness Racing heart rate, palpitations Excessive fatigue or unexplained shortness of breath with exercise Recent viral infection with chest pain or change in exercise [chop.edu]

  While the drugs effectively reduced patients’ arrhythmias, they had no effect on seizures, minimizing the chance that the seizures were simply misdiagnosed cardiac side effects. [futurity.org]

• Altered Mental Status

  A 10-year-old previously healthy child presented with sudden cardiac arrest after an insidious course of throat pain, fever, and progressive altered mental status. [ncbi.nlm.nih.gov]

  If the bradycardia is suspected to be the cause of acute altered mental status, ischemic chest discomfort, acute heart failure, hypotension, or other signs of shock, the patient should receive immediate treatment. [doi.org]

• Lethargy

  Side Effects Although most people tolerate them well, beta blocker side effects can include fatigue, lethargy, vivid dreams and nightmares, depression, memory loss, and dizziness. They can lower HDL ("good") cholesterol. [mountsinai.org]

• Tingling

  Angina pain or discomfort is typically described by people as fullness, tingling, squeezing, pressure, heavy, suffocating, or gripping. It is rarely described as stabbing or burning. [mountsinai.org]

The following diagnostic modalities and tests are done to patients suspected of having cardiac arrest:

• Electrocardiogram (ECG): This test uses electrodes that are attached on the chest and limbs to detect the electrical activity of the heart [8]. Characteristic ECG tracing can reveal that cardiac arrest has recently occurred.
• Cardiac enzymes: This type of blood test detects the enzymes that is leaked by the damaged heart. 
• Electrolytes: Important electrolytes that helps propagate cardiac impulses like potassium, sodium, calcium, and magnesium can be quantitatively measured in the serum.
• Drug test: The use of a drug assay from the serum can determine the possible agents that could have caused the arrhythmia and eventually cardiac arrest.
• Thyroid hormones: The high levels of thyroid hormones may induce cardiac arrhythmias. 
• Chest X-ray: This imaging technique will show the actual shape of the heart and determine the presence of heart failure.
• Echocardiogram: This imaging modality will elucidate the part of the heart involved in ischemia and demonstrate any valvular abnormalities.
• Coronary angiogram: Contrast dyes could be delivered through a cardiac catheter to show any functional blockage to the vessels of the heart. 

The following treatment modalities are used in patients who present with cardiac arrest:

• CPR: Witnesses of an attack must ensue CPR right away as soon as the event happens to increase the survival chance [9]. CPR is focused on the restoration of airways, breathing and circulation before the patient is brought to the emergency room.
• Defibrillation: This makes use of an electric shock that is directly delivered to the chest to reverse the fibrillation. 
• Anti-arrhythmic drugs: In the emergency room, patients are given anti-arrhythmics to control the arrhythmia that caused the arrest. The more common anti-arrhythmic drugs used during cardiac arrest include angiotensin converting enzyme (ACE) inhibitors, calcium channel blockers, and amiodarone. 
• Implantable cardioverter-defibrillator (ICD): As soon as the patient is stabilized, this battery operated implantable device may be installed to perpetually monitor the heart rhythm and automatically give out charged impulses to stabilize the heart rhythm when the need arises [10].
• Coronary angioplasty: This is the surgical repair of the clogged vessels to restore the free flow of blood towards the heart muscles. 
• Coronary bypass surgery: This makes use of vein to surgically bypass the clogged coronary artery and restore normal blood flow and circulation.
• Corrective surgery: This procedure is done to repair congenital defects that predisposes to arrhythmias
• Heart transplant: Patients with heart failure and have concurrently experienced cardiac arrest will greatly benefit from a heart transplantation surgery. 

The prognosis of cardiac arrest greatly depends on several signs during the CPR phase. Patients will have better outlook when they have an unsupported systolic pressure of 90 mmHg after the arrest. For those who became unconscious during the cardiac arrest, a spontaneous vascular circulation within less than 25 minutes offers a good chance of survival after the event. Patients who stay unconscious may have a good outlook if they show signs of neurological responsiveness upon stimulation [7].

The most common condition that leads to cardiac arrest are cardiac arrhythmias [1]. There are a number of cardiac conditions that may lead to life-threatening cardiac arrhythmias:

• Coronary artery disease: This refers to heart diseases characterized by the clogging of vessels due to cholesterol deposits. The most common cause of sudden cardiac arrest is coronary artery disease. 
• Myocardial infarction: This cardiac condition is considered a severe and acute coronary disease that may trigger ventricular fibrillation and cardiac arrest. 
• Cardiomyopathy: The progressive enlargement and thickening of the heart muscles may lead to abnormal cardiac function and abnormal electrical impulses generation.
• Congenital heart diseases: The innate abnormalities seen in congenital heart diseases can trigger a cardiac arrest as well as the scars left in the myocardium after its corrective surgery among adults. 
• Valvular heart diseases: The stenosis or the regurgitation seen in heart valves can advertently lead to chamber enlargements that increases the risk for an arrhythmia.
• Electrical disorders of the heart: This refers to primary heart conditions that may lead to abnormal heart rhythms like long QT syndrome and Brugada syndrome [2].

In the United States, cardiac arrests account for at least 350,000 deaths per year. The annual prevalence rate translates to 1 to 2 cases per 1000 adult population. More than half of the cases of cardiac arrest have an underlying diagnosed or undiagnosed coronary artery disease. Patient who survives a cardiac arrest event will have a higher chance of recurrence within the first 6 to 24 months from the initial attack. Internationally, mortalities associated with cardiac arrests number up to 7 million deaths per year [3].

Among the more than 300,000 cardiac arrest deaths in the United States, at least 40% of these occur unwitnessed. Mortality in cardiac arrest greatly depends on the competence of the by-stander to conduct an immediate cardiopulmonary resuscitation (CPR) to the victim, and the duration between the time of arrest and the conduction of the patient to the nearest hospital [4]. Deaths with cardiac arrest are seen to be higher among the black races compared to the white ones [5]. Men are more prone to cardiac arrest than women with prevalence ratio of 3:1. In the Framingham cardiac studies, the highest age incidence where cardiac arrest was observed were between the ages 45 to 54 years old [6].

The abnormal electrophysiologic mechanisms involved in the development of arrhythmias that lead to cardiac arrest are diverse and multifactorial. Alteration in normal physiology that may affect the normal electroconductivity of the heart impulses emanates from the subcellular, cellular, tissue, and organ level. In the subcellular level, abnormalities in the sodium, potassium, and calcium channels increase the likelihood of ventricular tachyarrhythmias and ventricular fibrillation. A sick sinus at the cardiac tissue level that causes asystole and bradyarrhythmias accounts for 20% to 30% of cardiac arrest deaths. Organic defects with hypertrophic cardiomyopathy and dilated cardiomyopathy are associated with high risk for sudden cardiac arrest.

The best way to prevent the occurrence of a cardiac arrest is to actively reduce its established risk factors. Patients with diagnosed cardiac diseases must abide religiously with their maintenance medications and visit their cardiologist regularly. A smoke free and a stress free lifestyle will prevent a number of cardiac events and would significantly lower the strain to the heart. A nutritious diet that is good for the heart should also be in place. An active lifestyle with regular cardio exercises will lower the likelihood of a sudden cardiac arrest.

Cardiac arrest is described to be the sudden and unexpected loss of cardiac function, consciousness, and breathing. Cardiac arrest usually ensues with an inciting electrical disturbance to the heart resulting in pump failure and the discontinuation of the blood flow in circulation. Cardiac arrest is considered a medical emergency, any delay in resuscitative efforts can result to sudden cardiac death and eventually the patient’s demise.

Definition

Cardiac arrest is a medical term that refers to the mechanical cessation of the heart resulting to the absence of circulating blood in the system resulting to a serious physiologic disturbance.

Cause

The great majority of cardiac arrest is caused by cardiac arrhythmias. There are a number of cardiac disorders that predisposes to arrhythmias like coronary artery disease, myocardial infarction, cardiomyopathy, and congenital heart diseases.

Symptoms

Patients in cardiac arrest will acutely be unconscious with eminent signs of shock. Dizziness, fainting, chest pain, and fatigue may sometimes herald the disease process.

Diagnosis

ECG is imperative in the face of a cardiac arrest. Ancillary tests like cardiac enzymes, electrolytes, echocardiography, chest X-ray, and coronary angiogram are also done when the patient is stabilized.

Treatment and follow-up

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