Cocaine Use and Heart Attack
Heart attack is the common name for a disruption of the normal supply of blood flowing to any given portion of the heart muscle; doctors and researchers refer to the condition more formally as a myocardial infarction. Without its required supply of oxygen-bearing blood, the heart muscle will die off quickly, producing a situation that can lead to serious heart damage or rapid death. People who use cocaine develop a number of problems in their normal cardiovascular (heart and blood vessel) health that contribute greatly to their heart attack risks. These problems occur in the aftermath of both short- and long-term cocaine use, and affect even casual users of the drug.
Heart Attack Basics
The heart gets its blood supply from two main vessels called the left and right coronary arteries, which extend from the body’s main artery, known as the aorta, and branch out into different sections of the heart muscle. It is the oxygen content in the blood flowing through these arteries that allows the heart to maintain its constant cycle of pumping and resting. In the general population, the conditions for a heart attack usually begin when a wax-like, cholesterol-containing substance called plaque builds up on the walls of the coronary arteries and encourages the formation of a blood clot. If a clot grows large enough to seriously reduce or cut off the blood flow through the affected artery, the tissue fed by that artery will start to die and the individual will start developing heart attack-related symptoms.
Plaque buildup in the arteries is part of an artery-hardening process called atherosclerosis (or arteriosclerosis), which typically occurs gradually over time in any given individual. While this buildup is the number one cause of heart attacks, other cardiovascular problems can produce the same result. For instance, the coronary arteries can develop a condition called vasospasm, which occurs when abnormal, severe narrowing of the artery interiors leads to a dangerous drop in blood flow. Some people also develop a heart attack as a consequence of serious heartbeat abnormalities or a form of pumping insufficiency commonly known as heart failure.
Cocaine’s Effects on the Heart
Cocaine use triggers a significant boost in the body’s supply of a chemical called norepinephrine, which acts as a neurotransmitter and increases the frequency of certain types of communication between nerve cells called neurons. Specifically, norepinephrine produces increasing levels of activity in the neurons of a system called the sympathetic nervous system, which branches throughout the body and helps provide involuntary control of the heart muscle and blood vessels, as well as a number of additional vital organs. When cocaine enters the bloodstream, activation of the sympathetic nervous system produces heart-related changes in normal body function that include blood pressure increases, heartbeat acceleration, and an increase in the amount of blood pumped by the heart in any given minute.
Mechanisms of a Cocaine-Related Heart Attack
Along with its basic alteration of normal heart function, cocaine use produces several specific changes that increase the risks for a heart attack. For instance, according to a study published in 2012 by the University of Sydney, cocaine use produces a form of artery stiffness that mimics the stiffness of atherosclerosis, and also produces abnormal thickness in the part of the heart muscle responsible for pumping oxygen-bearing blood out of the heart and into the aorta. Even in people who only use cocaine once a month, these heart attack-promoting changes remain in effect for a minimum of 48 hours.
According to a separate 2008 report sponsored by the National Institute on Drug Abuse, cocaine use also elevates the levels of components in the blood called clotting factors; in turn, this elevation increases the likelihood that a heart attack-inducing blood clot will form in one of the coronary arteries. Long-term cocaine use, in particular, contributes to an inflammation in the artery walls that promotes the onset of clot formation. In addition, use of cocaine can trigger serious cases of artery-blocking vasospasm within either of the two coronary arteries, or in the smaller vessels that branch from those arteries.
People between the ages of 18 and 45 are particularly susceptible to a cocaine-induced heart attack, according to a study published in 2007 in the journal “Clinical Medicine & Research.” These risks apply to all cocaine users in this age group, whether or not they have a previous history of heart- or blood vessel-related health problems. As stated previously, the heart-endangering effects of cocaine appear in people who use the drug as infrequently as once every 30 days.