heart attacks

Heart attacks are surprisingly common and every one of us, has at some point, had a family member or loved one that either had or succumbed to a heart attack. In common medical terminology, doctors often refer to heart attacks as "myocardial infarction" which is a fancy word that literally states that heart muscle is dying.  But heart attacks do not always come in one flavor. In fact, heart attacks are only one extreme of a spectrum of diseases that are known as heart disease.

In this segment, I won't limit myself to explaining heart attacks, but will focus on giving you the difference between "heart disease" and "heart attacks". In a nutshell, this difference has to do with acuity of the problem than anything else. But let's get to that a bit later. For now, lets understand what happens.

Your heart is a big strong muscle that is designed to pump blood to the rest of the body. It does so, by contracting and relaxing in turn, a process which we call the "cardiac cycle". Most of us can hear the outcome of the contraction-relaxation cycle as a "heart beat". In order for the heart to keep pumping, as you can imagine, an inordinate amount of energy is required. This energy comes from the blood which it pumps, which carries oxygen and other nutrients for the muscle to use. So, herein lies the interesting paradox: If the heart pumps blood to give blood to all the vital organs, who gives blood for the heart muscle to pump? Well, it turns out that the heart has to do this as well. It does so by "stealing" a bit of blood that it pumps, back into itself, via a group of arteries called coronary arteries. In Latin, corona means "crown" and these arteries sit right on top of the heart and shunts away a little bit of blood from the body as the heart pumps. This blood circles back through the heart and allows the heart to keep squeezing. 

It's a fairly simple process, but you can imagine what happens if this process goes awry. For example, if decades of sedentary lifestyle and bad food habits, smoking, and other risk factors cause lipids to get placed on the wall of these arteries, these lipid deposits can over time "choke" the artery off and prevent adequate blood flow from happening. When this happens, patients might be comfortable at rest, when there is just enough blood to get through the blockage (chokehold) to supply the heart muscle, but when the heart has to pump stronger and harder, it absolutely cannot.