Cardiac Arrest occurs when there is an irregularity in heartbeat, better known as arrhythmia. It is often caused by disrupted electrical signaling. This disrupted electrical impulse results in sudden cessation of the heart. The blood is no more pumped to vital organs like brain, lungs, etc. and the person loses consciousness within seconds. If undetected, the person may lose his life within minutes. Hence, a fast medical help is a must. Cardiac arrest is often confused with heart attack, but the two cases are different. Heart attack may cause an abnormality in heartbeat.
For a cardiac arrest, you may see one of these symptoms :
- The person may fall unconscious suddenly without any pain or uneasiness.
- Since the heartbeat ceases, pulse is not felt at any major artery.
- Due to the non-delivery of blood to the lungs, breathing halts as well.
Sometimes dizziness, fatigue, vomiting, sudden blackouts may occur prior to cardiac arrest, but mostly the symptoms are unseen.
The heart beats due to electrical impulses that are generated at two nodes, namely Sino-Atrial node (SAN) and Atrial-Ventricular node (AVN). The impulses generated by these create a rhythmic contraction and relaxation of the heart, and causes it to beat. The SAN is also known as “the primary pace- maker” of the body. AVN known as “the secondary pace-maker”, on the other hand cannot generate these by itself. The signals triggered by SAN are spread to AVN and then further to the entire cardiac musculature. Cardiac arrest results when SAN is not able to generate the electrical impulses properly.
It is the most common reason, where the heart specially the lower chambers shudder but are unable to pump any blood.
This is a condition in which the cholesterol along with calcium salts form plaque in the coronary artery of the heart, which is a major blood vessel supplying blood to the musculature. This results in the loss of supply of oxygen and as oxygen tension develops in the heart, irregular electrical conduction may occur.
Longer QT Syndrome
It is a heart abnormality seen in some people, where the heart valves are either thick or weak for taking up the electrical impulses and undergo synchronized beating.
Valvular Heart Disease
The heart valves may either leak or get constricted causing thickening of the heart muscles. This leads to the developing of a stress, and arrhythmia.
Brain is the ultimate center for the control of any function in the body including heartbeat. If in case the heartbeat center of the brain undergoes a stress or is under a low oxygen tension due to hemorrhage, arrhythmia can result.
There are numerous factors that lead to cardiac arrest or even death from the same. However, the leading factors for the same include:
Previous history of heart attack:
A major faction, i.e. up to a 75 percent of cardiac arrest is linked to previous occurrence of heart attack especially in a brief time period of 6 months after the attack has occurred.
Coronary Artery Disease:
Abnormal Heart Rhythm:
Many heart abnormalities that lead to abnormal rhythm of the heart can be a major inducer of cardiac arrest. These abnormalities include Wolff-Parkinson-White syndrome, Long QT syndrome, heart block or dangerously low heart rhythm.
Substance or drug abuse can be a major contributor to the induction of a cardiac arrest given the fact that it can trick the brain into release of various hormones in an uncontrolled pattern which can essentially harm the functioning of your heart.
Obesity, Diabetes and Blood Pressure:
Use of Diuretics:
Use of diuretics can lead to major changes in the level of magnesium and potassium in the blood that leads to onset of a cardiac arrest even if you do not suffer from any kind of heart disease.
If sudden or chronic chest pains, random changes in the breathing pattern, irregular pulse rate or shortness of breath persist, the patient should be immediately taken to a doctor. Survival chances of the patient become very rare, if the cardiac arrest lasts for more than 8 minutes. Helping the person with continuous and even compression on his chest or perform CPR during a cardiac arrest, by the time medical help arrives should be the first aid. Apart from that, the airway should be continuously checked and rescue breaths should be provided. If the unconscious person, being helped stops breathing, it should be a matter of immediate concern.
The treatment for cardiac arrest should be immediately started by the doctor.
- Usage of a defibrillator : Defibrillator delivers a shock to the heart and triggers the SAN to generate electrical impulses, so that the normal heartbeats can be restored. After each shock delivery, CPR is performed to stimulate the heart muscles for contractions.
- The medical personnel check for the electrolyte imbalance, presence of any heart disease, or a possible heart attack and administer medications accordingly to stimulate heart for normal beating.
- The doctors would advise use of drugs for long term and permanent cure of cardiac arrest. The drugs include angiotensin converting enzyme (ACE), Cordarone, Pacerone and calcium ion channel blockers.
- Coronary angioplasty : This is done to remove the blockage of the coronary artery and restore normal flow of blood through heart. Stents may also be added to the arteries to prevent them from further constrictions.
- Introducing an artificial Pace-maker : artificial pacemakers made up of lead electrodes are available in the market. These are fit into the heart near the SAN and work similar to the natural pace-maker for generation of impulses. These are known as Implantable cardioverter defibrillator.
- Corrective heart surgery : Any abnormality in the heart can also be cured by just correcting the heart condition as in case of cardiomyopathy. This would improve the flow of blood through the heart, thus lessening the chances of a cardiac arrest.
Post-surgical monitoring of the patient’s heart condition should be done to assure no further complications in his health conditions.
Image Credits : Featured Image