Cardiac Arrest: Causes, Symptoms & Treatment Options

Cardiac arrest refers to a sudden, unexpected loss of hearing function. Although it can be lethal, getting treatment as soon as possible can improve your prognosis. 

Electrical impulses regulate the rhythm of the heartbeat. The heartbeat becomes irregular when the pattern of these impulses changes – also known as arrhythmia – whose intensity and severity might vary. In severe cases, arrhythmias can lead to cardiac arrest- a medical condition that might result in disability or death. As soon as you see any signs of cardiac arrest in yourself or someone you’re with, get emergency medical attention.

However, it must be noted that a heart attack is not the same as sudden cardiac arrest. When blood supply to a portion of the heart is restricted, a heart attack occurs, and cardiac arrest does not happen due to blockage. On the other hand, a heart attack may result in a shift in the electrical activity of the heart that triggers rapid cardiac arrest. The symptoms of cardiac arrest might range from no pulse to palpitations, no breathing, loss of consciousness, etc.

But it must also be noted that cardiac arrest sometimes shows no symptoms. So, seeing a doctor in case of minor discomfort is also advisable. 

What Causes Cardiac Arrest?

Any changes in the heart’s electrical activity- which controls the rate and rhythm of the heart, can cause cardiac arrest. The most common cause of cardiac arrest is irregular heart rhythm, known as ventricular fibrillation. This reduces the effective blood pumping – instead, the lower heart chambers quiver ineffectively due to irregular and rapid cardiac signals. Your risk of experiencing this kind of heartbeat issue may increase if you have certain cardiac diseases. However, even those without a heart condition may experience sudden cardiac arrest. Here are some of the causes of cardiac arrest: 

• Coronary Artery Disease – If the heart’s arteries fill with deposits of cholesterol and other materials, the heart’s blood flow may reduce and sudden cardiac arrest may occur.
• Heart Attack – A heart attack can result in ventricular fibrillation and abrupt cardiac arrest. Heart attacks are frequently caused by severe coronary artery disease. Moreover, scar tissue after a heart attack may remain in the heart. The heartbeat may alter as a result of the scar tissue.
• Heart Enlargement Known as Cardiomyopathy – This condition results from a strain in the heart muscle walls. The cardiac muscle thickens or grows larger. 
• Heart Valve Dysfunction – The heart muscle may expand or thicken due to leakage or narrowing of the heart valves. An elevated risk of developing an arrhythmia occurs when the chambers grow or weaken due to stress from a tight or leaking valve.
• Congenital Heart Defect – A congenital heart defect is the term for a cardiac condition existing from birth. A congenital cardiac condition frequently causes sudden cardiac arrest in children or teenagers. Sudden cardiac arrest is also more likely to occur in adults who have undergone surgery to address a congenital cardiac abnormality.
• LQTS (long QT syndrome) and Other Cardiac Signalling issues – Heart arrhythmias are brought on by disorders including Brugada syndrome and extended QT syndrome. Sudden death can happen if the heart rhythm isn’t rapidly restored. Sudden mortality is especially risky for young people with LQTS.

What are the Symptoms of Cardiac Arrest?

Cardiac arrest warning sigs are frequently the early symptoms. Receiving medical attention before cardiac arrest may save your life. Here are the symptoms of cardiac arrest: 

• Grow lightheaded (dizziness)
• feel weak or exhausted
• Shortness of breath
• Vomiting
• Palpating

If you or someone you are with encounters these symptoms, you need to get emergency care right away:

• No pulse
• Chest discomfort
• Unconsciousness and collapse
• Respiratory difficulties or cessation of breathing

What are the Treatment Options for Cardiac Arrest?

It is essential to seek medical attention if you have any abnormal cardiac symptoms. To start an effective treatment process, doctors will perform specific tests, such as an electrocardiogram, to identify abnormalities in the patient’s heart rhythm. Here are some tests that can help people with cardiac arrest: 

• Blood tests – These tests can look for signs of a heart attack and measure the magnesium and potassium levels in the blood. 
• Chest X-ray – They look for other signs of diseases in the heart. Also, it shows the shape and size of the heart and if a patient has a heart failure. 
• Nuclear Scan – This test is done with a stress test, which helps see problems related to blood flow. Healthcare providers inject a tiny amount of radioactive material, called a tracer, through an IV, which is tracked by a special camera and sees the inside of the person (heart and lungs). 
• Cardiac Catheterization – This test helps healthcare providers see blockages in the heart arteries using a long, thin, and flexible tube inserted in a blood vessel, usually in the wrist or groin. A small amount of dye is injected, which helps the arteries show up more clearly on X-ray images and videos. 
• Echocardiogram – This test shows how blood flows through the heart and the heart valves as the sound waves create images of the heart in motion. 

Several other tests may be done, which will be prescribed only if required, depending on your symptoms. The cardiology doctor will evaluate the diagnostic reports and create a treatment plan. 

Generally, immediate treatment is required in cases of cardiac arrests, which is often provided even before any diagnostic tests.  First line of treatment includes Cardiopulmonary resuscitation (CPR) or Defibrillation, which involves resetting the heart rhythm. 

Cardiopulmonary resuscitation (CPR):  In cases of sudden cardiac arrest, where the heartbeat has stopped, cardiopulmonary resuscitation, or CPR, is immediately performed. It involves hard and quick chest compressions. This immediate CPR recommendation is for both first responders and untrained observers. It’s important to provide CPR immediately if someone suffers a cardiac arrest, even if you aren’t sure how to do it. 

Defibrillation: Defibrillation involves applying an electrical shock across the chest using either adhesive pads or a pair of manual paddles placed on the patient’s chest. In order to effectively defibrillate, defibrillators usually use a biphasic waveform, which requires a lower energy level.

Here are some other treatment plans for cardiac arrest and related cardiac issues: 

Medicines – The heart rhythm can be restored with anti-arrhythmic medications. Additional medications that may be used to treat or reduce the risk of sudden cardiac death include –

• Beta-blockers.
• Inhibitors of the angiotensin-converting enzyme (ACE).
• Blockers of calcium channels. 

Surgeries – Surgeries might be necessary to open a blockage, treat heart rhythm problems, or place a device to ensure the heart functions properly. Here are some surgical processes involved – 

• An Implantable Cardioverter Defibrillator (ICD), similar to a pacemaker, is placed near the collarbone and continuously monitors the heart rhythm. If the device detects an abnormal heartbeat, it sends a shock to reset the heart rhythm. 
• Coronary Angioplasty, or percutaneous coronary intervention, opens blocked or clogged heart arteries. It can be done during coronary catheterization when the doctors find narrowed arteries. 
• Coronary Artery Bypass Surgery, also known as CABG (Coronary Artery Bypass Grafting), creates a new pathway for blood to flow around a blocked artery to the heart, which helps restore the blood flow to the heart. 
• Radiofrequency Catheter Ablation is done to block a faulty pathway that might cause irregular heartbeats. One of the more flexible tubes, also known as a catheter, is threaded through the blood vessels to inside the heart, creating small scars in the heart and blocking irregular heart signals. 
• Corrective Heart Surgery is a treatment to correct congenital heart valve disease or heart muscle disease. 

In addition to this treatment, doctors might also prescribe lifestyle changes, such as:

• Quit smoking
• Reduce the consumption of alcohol 
• Eat a healthy diet such as – omega-rich food (salmon), whole-grain food (brown rice), low fat dairy (feta), etc.

Conclusion

Cardiac arrest is a life-threatening condition marked by sudden loss of heart function. Symptoms include sudden collapse, loss of consciousness, and absence of pulse or breathing. Immediate treatment with CPR and defibrillation is critical for survival. Diagnosis involves medical history, physical examination, and various tests such as ECG and blood tests. 

Lifestyle changes such as regular exercise, a healthy diet, and avoiding smoking can lower the risk. However, it’s paramount to consult a healthcare provider for personalized advice. Early detection and management significantly improve outcomes, emphasizing the importance of proactive healthcare in mitigating cardiac arrest risks.