For the hundreds of thousands of people who experience a heart attack annually, the life-threatening experience undoubtedly leads to further fear, anxiety, and a slew of questions about their health, wellness, and future. Since heart attacks differ in scope of damage, severity, and subsequent necessary care, people who have experienced a heart attack and their loved ones may feel overwhelmed by the maintenance that follows such an event. Some patients may experience a weakened heart function following a heart attack. These individuals exhibit an increased risk of sudden cardiac arrest (SCA), a life-threatening condition with no visible warning signs.
Left untreated, the onset of sudden cardiac arrest can lead to death within minutes. But for some individuals who have experienced a heart attack, there are treatment options that can provide security and protection against SCA, including devices like the ZOLL LifeVest.
Many people believe a heart attack and SCA are the same, but the two conditions vary greatly and require vastly different intervention. Understanding the difference between these conditions can help to save lives.
What is a Heart Attack?
Heart attacks occur when the blood flow and supply to a specific part of the heart is diminished or blocked. This lack of oxygenated blood flow causes affected chambers of the heart to die. Treatment for a heart attack often includes an emergent procedure, such a stent placement or bypass surgery. These procedures are meant to clear blockages and restore vital blood flow to the heart.
Though everyone has seen stereotypical images of a heart attack occurring, complete with a relatively fit older man clutching at his chest, heart attack symptoms expand beyond this image. With various symptoms, heart attacks can be recognized by individuals who are experiencing them, as well as bystanders and loved ones. Most notably, individuals experiencing a heart attack often remain awake and aware of their symptoms.
Common symptoms include nausea, lightheadedness, sweating, shortness of breath, radiating pain in the shoulders and jaw that moves down the arm, and pain or discomfort in the chest that can last a few minutes over a series of several days. For women, common symptoms may also include swelling in the ankles and legs, overwhelming weakness, and stomach pain. Together, any combination of these physical symptoms can alert individuals of immediate danger. They can also alert bystanders and loved ones to seek medical attention, maximizing the chances of survival and limiting damage to the heart.
While the prevalence of heart disease has been focused traditionally on the male population, heart disease is considered the most common cause of death for women. With women often experiencing different heart attack symptoms than their male counterparts, it is especially important for women to learn about the additional symptoms of a heart attack.
What is Sudden Cardiac Arrest?
A patient’s heart rhythm is controlled by the heart’s internal electrical system, and when that system breaks or is otherwise compromised, this can trigger a life-threatening rapid heartbeat, known as sudden cardiac arrest (SCA). When this occurs, the heart stops effectively beating, quivering or shaking instead of pumping blood to the brain and body. Without the needed supply of blood to the body and brain, SCA often causes immediate loss of consciousness, leaving victims unable to summon medical attention if alone.
As the third leading cause of death in the United States, sudden cardiac arrest is a life-threatening condition with a very small window of opportunity for successful medical intervention. If untreated, death results within minutes. With no visible symptoms or preemptive warning signs, SCA events are difficult to predict by individuals who have them and are recognized by bystanders and loved ones only after an individual loses consciousness, lessening the chances of survival.
How Does a Heart Attack Differ From Sudden Cardiac Arrest?
Perhaps the largest differentiator is that SCA victims typically lose consciousness immediately while heart attack victims often remain awake. In the event of a heart attack, individuals do not lose consciousness, and the heartbeat remains functional. Conversely, in the case of SCA, individuals lose consciousness within seconds, and the heart does not continue to beat effectively. While it is critical to summon emergency medical help in both cases, people who experience SCA events while alone are unable to do so, increasing the risk of mortality greatly. Thus, while the survival rate for heart attacks is somewhat high, the average survival rate for SCA remains only about 10 percent.
Heart attacks are sometimes described as a “plumbing issue,” as they occur when there is a blockage in the heart’s internal system of arteries and veins (the “pipes”), disrupting blood flow to the heart’s muscle. Conversely, SCA can be seen as an “electrical issue,” as it occurs when the heart’s internal electrical system is disrupted, causing a life-threatening an irregular heartbeat.
While heart attacks and SCA are different, they can be related. Patients who have suffered a heart attack and have a reduce heart function are at high risk for SCA, particularly in the first three months after their heart attack. For patients with a known risk of SCA, there are treatment options so that patients can have protection.
Increased Risks for SCA
People who have experienced a heart attack are at a heightened risk of experiencing SCA. After surviving a heart attack and subsequent emergency medical procedures, some people are left with weakened hearts, unable to pump sufficient amounts of blood throughout the body. Following a heart attack, the dead or damaged heart muscles can impact the heart’s electrical functioning, as the electrical systems cannot effectively work with the damaged or dead muscle tissue.
Even with the implementation of stents and the surgical removal of clots, the heart does not immediately regain the power to generate 100 percent effective activity, putting people at an increased risk of SCA as the heart’s operations regain functionality. Similarly, if subsequent surgical intervention is needed in the form of bypass surgery or the installation of a permanent defibrillator, this places people at a heightened risk of SCA on a longer-term basis.
Ejection fraction (EF) is used by cardiologists to determine how well the heart is pumping blood. Ejection fraction is calculated by the percentage of blood pumped through the heart with each beat. A normal EF is about 55-70 percent. Following a heart attack, some patients experience a much lower EF. An EF of 35 percent or below increases a person’s risk of SCA.
How ZOLL LifeVest Provides a Life-Saving Service
When a person experiences a life-threatening rapid heart rhythm, the heart stops beating effectively and requires defibrillation shocks to restart a normal rhythm. This life-saving defibrillation can restore a life-sustaining heartbeat and allow people to regain consciousness. When successful defibrillation occurs at the onset of SCA, a person’s chance for survival considerably increases.
Outside of the hospital, the survival rate of SCA is only about 10%. For patients who have a known risk of SCA, such as those who have recently suffered a heart attack and have a weakened heart function, there are treatment options so that patients can have protection from SCA. The ZOLL LifeVest wearable cardioverter defibrillator (WCD) can provide constant monitoring, along with autonomously deployed treatment shocks in the event of SCA, providing patients with the support they need when they are at their most vulnerable. ZOLL LifeVest is a temporary therapy worn by patients during their cardiac recovery, allowing their physician time to assess their long-term risk for SCA.
ZOLL LifeVest is designed to be worn at all times, except for a short shower or bath. When worn as directed, ZOLL LifeVest continuously monitors the heart rhythm. If a life-threatening rapid heart rhythm is detected, the WCD is designed to automatically deliver a treatment shock without the need for any human intervention, providing the life-saving defibrillation crucial to restoring the heart’s rhythm. Typically this entire process, from detecting a life-threatening heart rhythm to delivering a treatment shock, takes less than one minute, generating a swift and timely response.
How ZOLL LifeVest Works
Composed of three main parts, the WCD contains a wearable garment, an electrode belt, and a monitor. The garment is intended to be worn directly against the skin and contains the electrode belt, which can detect irregular heart rhythms and administer life-saving treatment to restore the heart’s rhythm. The monitor continuously records heart rate. The monitor can be worn attached to the belt loop of pants or with a shoulder strap. ZOLL LifeVest is designed to allow patients to return to most daily activities.
For people who have recently suffered from a heart attack, this return to normalcy can be an important part of recovery. During cardiac recovery, ZOLL LifeVest can provide patients peace of mind knowing they have protection from SCA.
