Moment: Thursday, January 6th, 2017
”Physically or emotionally, the heart is a muscle; the more you use it the stronger it gets.”
My love for the heart was ignited when I began teaching Hands-Only CPR classes in high school, and I remember in high school, our teachers had invited a panel of healthcare professionals from Baylor Scott and White-Round Rock, and I mustered up the courage to ask what I should do to prepare to become a doctor. I felt a little ridiculous asking that when I still had about 7 years of education before I would even set foot in a medical school, but I knew that if I was going to commit to a career, I wanted to make sure I liked it, so I tried to learn as much as I could.
A P.A. from the cardiology department told me that the most important thing to learn is how the heart (and every other organ in your body) works when it’s in 100% mint condition, and then try to figure out what happens if you make one single tiny thing go wrong, because you can’t find a problem if you don’t know what the normal condition is. I really took this piece of advice to heart (lol) and committed to learning about the heart. My health science teacher, Mrs. Hamilton, helped me learn the flow of blood by creating a floor mat in the shape of a heart and letting me walk through it like I was a red blood cell. I watched YouTube videos about how to read EKG’s and even went through a life-sized heart at a HOSA conference.
I was a pro at it. I could name all of the major structures of the heart and identity every blip on a heart monitor. But over the years, it started to fade away, as memory tends to do, but it all came rushing back in the past few weeks when we went through the heart unit in my Anatomy and Physiology class (I just took my final yesterday!). I’ve just gotta say, the heart is just as awesome as I remember it, and every single lecture was just another reminder that this is exactly what I want to dedicate my life to.
With this quarantine, I've had the time to truly appreciate what I'm learning instead of just cramming it into my brain, so I just wanted to share a little bit about the amazing little ticker that lives inside of you. They say that teaching helps you learn better, so here goes!
The heart has four chambers: the right and left atria, and the right and left ventricle. The blood comes in the heart from the body, drained of oxygen, through the superior and inferior vena cava into the right atrium, which just means “room”. I know it looks like the right atrium is on the left, but you just have to pretend like you’re looking at a patient and base your directions off that. I’m convinced that I’m so directionally challenged solely because of this rule.
Anyways, gravity does most of the work to make the blood go from the right atrium down to the right ventricle, but there’s an emphasis on “most”. There’s still a little blood left in there, but we need to get it all out in order to make sure the body is as oxygenated as possible, so the right atrium contracts to squeeze the last bit of blood out, kind of like the end of a toothpaste tube. Then once all the blood is in the right ventricle, the gate between the right atrium and ventricle, known as the tricuspid valve, slams shut so the blood can’t go back.
Now the blood is trapped in the right ventricle, so it contracts to try to push the blood out, and it winds up going through the pulmonary (meaning lungs) semilunar valve and out the pulmonary arteries into the lungs to FINALLY pick up some of the life-giving oxygen we all need. The blood circles back around to the heart through the pulmonary veins and ends up in the left atrium.
Gravity once again does its duty by letting the blood flow down into the left ventricle, and after the atrium contracts to coax in the rest of it, the bicuspid valve slams shut in a similar fashion to the tricuspid valve earlier. Then the left ventricle contracts to push the now-oxygenated blood through the aortic semilunar valve into the aorta, the largest artery in the body, which carries blood with oxygen and nutrients to the entire body.
Those two valve slams that we talked about are what creates the “lub-dub” you hear through a stethoscope or feel when you check your pulse. The intricacies of the heart are so incredible, because guess what? ALL of that happens...in an organ the size of your fist. *mind blown*
