A Sudden Cardiac Arrest (SCA), also known as Sudden Cardiac Death, is a fast and abrupt cessation of heart functions, caused by an alteration in heart rates. It occurs few instants after the manifestation of its symptoms, which you can read about here(link), affecting also people who have never been diagnosed with a heart disease.
SCA is often confused with a Heart Attack which is, however, a different condition. In a Heart Attack, the deficit in heart functions is caused by an obstruction of a blood vessel, that would cause itself a stop in the blood flow to the heart. This lack in blood supply may cause the death of the heart muscle tissue but does not automatically imply the victim’s death. There are also other differences .
On the other hand, a Sudden Cardiac Arrest is an electrical problem which can sometimes be provoked by a serious Heart Attack. More often, however, it is provoked by an alteration in the heart electrical system that affects its pumping rhythm. This alteration is called arrhythmia and can happen in two directions: if the heart rate is slower than 60 beats per minute, the heart is experiencing Bradycardia; if the rate is faster than 100 beats per minute, a Tachycardia is diagnosed.
It’s clear that arrhythmias affect deeply heart functions, compromising its ability to pump blood to the body. For this very reason, symptoms of arrhythmia could be feeling tired, passing out, anxiety, shortness of breath, chest pain, lightheadedness or loss of consciousness, since the body is not properly receiving blood, oxygen and nutrients. Arrhythmias can often be momentary and won’t even be perceived. Sometimes, they can result in even more serious conditions such as the ventricular tachycardia and the ventricular fibrillation, which cause cardiac arrest.
The ventricular fibrillation is the most serious issue regarding cardiac rhythm. It provokes an incredibly fast and chaotic rate, during which the lower chambers quiver and the heart cannot pump any blood, leading to cardiac arrest.
The most effective way to stop a Sudden Cardiac Arrest caused by ventricular fibrillation is to use a defibrillator on the victim, so having an AED nearby can be lifesaving when this unexpected event occurs.
Apart from ventricular defibrillation, SCA can have several other causes. Among them, congestive heart failure, in which the heart is not pumping enough blood to meet the body’s needs, and heart valve problems can increase the risk of SCA. Another condition to mention is cardiomyopathy, which comprehend a number of disease regarding the mechanical properties of heart muscles which, as well as Myocarditis, heart muscles inflammations, can also be an SCA cause. Moreover, there are some diseases regarding the electrical system directly or genetic conditions such as the Brugada Syndrome, with which people are born, that can happen to affect heart rate and cause Sudden Cardiac Arrest.
Some of these conditions can be tricky to diagnose, the people affected may not present any of the symptom until the SCA occurs. For women and kids they can be even more difficult to discover, since not a lot of attention is given to prevention. Much more attention is given to men older than 40 years, however, those syndromes can hit everyone. And still, it is unfortunately very uncommon to get an heart check like an ECG before turning 30. Find out which are the exams recommended to prevent Sudden Cardiac Arrest.