Common Causes of Cardiac Arrest in Adults

Cardiac arrest in adults is most commonly caused by sudden cardiac death due to coronary artery disease. The underlying mechanism involves a sudden interruption of blood flow to the heart. This can be compared to a car engine without fuel—it will stop running, and the entire system shuts down. Similarly, if the heart does not receive adequate blood supply, it can cease beating. When the heart stops, it leads to immediate respiratory arrest and can be fatal within minutes if not treated promptly.

Understanding the Mechanism Behind Cardiac Arrest

When blood flow to the heart is abruptly cut off, the heart muscle becomes deprived of oxygen and essential nutrients. This lack of oxygen can cause the heart's electrical system to malfunction, resulting in arrhythmias or, ultimately, cardiac arrest. Without immediate intervention such as cardiopulmonary resuscitation (CPR) or defibrillation, the outcome can be fatal.

Triggers of Sudden Cardiac Arrest

Several lifestyle-related factors can contribute to sudden cardiac arrest. Excessive physical strain, chronic sleep deprivation, and intense emotional stress can all trigger coronary artery spasms or constriction, which may interrupt blood flow to the heart. These conditions can cause the heart to stop beating, leading to life-threatening consequences.

Coronary Artery Disease and Blood Clots

Another significant cause of cardiac arrest in adults is coronary artery disease, where plaque buildup inside the arteries can rupture. This rupture can lead to the formation of a blood clot, which blocks the flow of blood to the heart. In many cases, the blockage occurs in the left main coronary artery—an essential vessel supplying blood to the heart muscle. When this happens, cardiac arrest can occur within minutes, making it a critical and time-sensitive medical emergency.