Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. Hey brain Stuff,
Speaker 1: Lauren Vogelbaum. Here. Your heart works NonStop to deliver nutrient
Speaker 1: rich blood to every part of your body, but its
Speaker 1: first priority is always to take care of number one, A,
Speaker 1: meaning itself. You can think of it sort of like this.
Speaker 1: When you deposit money into a checking account, you establish
Speaker 1: a system where all of your money passes from you
Speaker 1: to your bank and then follows one of two paths.
Speaker 1: It may either earn interest while the bank loans it out,
Speaker 1: or it may scatter to pay for your various expenses,
Speaker 1: but the bank most likely ear marks some small portion
Speaker 1: of those funds for itself. First. When you look at
Speaker 1: your monthly statement, you'll see all of the deductions you
Speaker 1: made from your account, and there at the top a
Speaker 1: monthly checking fee from the bank. Your heart handles blood
Speaker 1: in pretty much the same way. In the average adult human,
Speaker 1: the heart pumps about two thousand gallons of blood a
Speaker 1: day through its chambers. That's about seven five hundred liters.
Speaker 1: Of course, the average adult human does not hold that
Speaker 1: much blood. The heart is pumping the same blood over
Speaker 1: and over. Your heart beats about one hundred thousand times
Speaker 1: every day to supply the cells in your body with
Speaker 1: freshly oxygenated blood. That's a seriously powerful muscle, and it
Speaker 1: means that even though your heart's function is to provide
Speaker 1: other muscles with blood, it needs its own supply too. Today,
Speaker 1: let's talk about how your heart gets that blood and
Speaker 1: what can go wrong when it doesn't. Your heart receives
Speaker 1: oxygenated blood in the same way that your brain, your feet,
Speaker 1: and the rest of your body does through an artery,
Speaker 1: but the heart takes the very first cut of the
Speaker 1: good stuff arriving in from the lungs, just as the
Speaker 1: bank makes sure its fees are paid first. To mix
Speaker 1: our metaphors, the heart basically has its own freeway exit
Speaker 1: for fresh blood that it's just pumping out. The oxygenated
Speaker 1: blood coming out of the heart is getting on the
Speaker 1: freeway to the rest of your body, and a little
Speaker 1: bit gets off at the first overpass and takes a
Speaker 1: side road back into the heart. But okay, let's back
Speaker 1: up a little. Your heart is divided into four chambers,
Speaker 1: the left atrium and left ventricle, and then the right
Speaker 1: atrium and right ventricle. The left side is receiving fresh,
Speaker 1: oxygen rich blood from your lungs, then sending it through
Speaker 1: the left atrium down into the left ventricle, where the
Speaker 1: heart's contractions forces it throw valve into the aorta at
Speaker 1: one of the heart's main outward bound pipelines. The right atrium,
Speaker 1: on the other hand, handles oxygen poor blood coming in
Speaker 1: from all over the body and ships it down into
Speaker 1: the right ventricle. From there, the heart's contractions force this
Speaker 1: less than fresh blood out into the pulmonary artery, which
Speaker 1: forwards it to the lung for reoxygenation. The heart can't
Speaker 1: just take its oxygens straight from the blood that's constantly
Speaker 1: passing through its chambers, partially because if that were the
Speaker 1: way it worked, the cells on the right side of
Speaker 1: the heart that intakes used blood from the body would
Speaker 1: be out of luck, so the rest of the body
Speaker 1: doesn't want the heart's cast offs. If the heart replenished
Speaker 1: its own oxygen supply directly from the river of blood
Speaker 1: flowing through it, the blood leaving the heart would have
Speaker 1: less oxygen to deliver to the body. Instead, the muscle
Speaker 1: exercises some restraint and feeds itself through arteries that run
Speaker 1: off of the aorda, just like every other part of
Speaker 1: the body. These arteries are called appropriately the left and
Speaker 1: right coronary arteries. Once the aorta leaves the heart, blood
Speaker 1: can branch off almost immediately into the coronary arteries. The
Speaker 1: left coronary artery feeds the left side of the heart
Speaker 1: and usually splits into two large branches, the left anterior
Speaker 1: descending which descends down the front of the heart, and
Speaker 1: the left circumflex, which winds back around the heart. The
Speaker 1: right cornary artery supplies the right side of the heart
Speaker 1: and the nodes that provide electrical signals to the heart.
Speaker 1: Plus it branches off into the posterior descending artery, which
Speaker 1: descends down the back of the heart. Interestingly, we don't
Speaker 1: all have the same network of arteries feeding our hearts.
Speaker 1: Some people have a third main coronary artery that juts
Speaker 1: off of the aorta, and others have only a single
Speaker 1: main coronary artery. Sometimes it's the right one instead of
Speaker 1: the left, that branches into two more arteries. Regardless of
Speaker 1: these harmless differences, the result is the same. The arteries
Speaker 1: branch off in two smaller arteries, and all the arteries
Speaker 1: and their branches wrap around the heart sort of like
Speaker 1: a crown, hence the term coronary. This way, all of
Speaker 1: the heart's tissues receive a fresh blood supply, giving it
Speaker 1: the fuel it needs to pump day in and day out.
Speaker 1: But what happens if something goes wrong? Problems and blockages
Speaker 1: in the coronary arteries are what cause heart attacks. These
Speaker 1: arteries start out big, soft, and smooth inside. They're usually
Speaker 1: around three to four millimeters in diameter, which is a
Speaker 1: little bit over a tenth of an inch, or around
Speaker 1: the size of a cocktail straw. But as we grow older,
Speaker 1: we can damage those once supple arteries via wear and tear, stress,
Speaker 1: fatty and salty foods, and not getting enough exercise. Over
Speaker 1: the decades, they collect plaque, which are fatty deposits along
Speaker 1: their inner walls, causing the arteries to harden and narrow.
Speaker 1: This condition is known as arthrosclerosis. Unchecked, it can develop
Speaker 1: into coronary artery disease, also known as coronary heart disease.
Speaker 1: As this condition advances, a number of things can happen.
Speaker 1: For example, if a portion of your heart muscle is
Speaker 1: receiving some but not enough oxygen due to partially blocked arteries,
Speaker 1: your heart won't be happy about it. The muscle will
Speaker 1: file a formal complaint with you in the form of
Speaker 1: chest pain called angina. This can feel like pressure or
Speaker 1: burning in your chest, like it's difficult to draw breath, or,
Speaker 1: especially in women, like discomfort in the neck, jaw, or back,
Speaker 1: maybe along with a stabbing chest or stomach pain. Angina
Speaker 1: usually happens when you start exerting yourself, maybe if you're
Speaker 1: climbing a flight of stairs or taking a brisk walk,
Speaker 1: and will usually go away within a couple minutes once
Speaker 1: you've had a chance to rest. You know, your heart
Speaker 1: doesn't require much oxygen when you're sitting by the pool,
Speaker 1: so it's usually fine, but the muscle will start feeling
Speaker 1: the lack of oxygen when you start swimming laps. This
Speaker 1: is called stable angina. It's something to pay attention to
Speaker 1: and inform a healthcare provider about, but it's not an emergency.
Speaker 1: Is an emergency is if you feel angina when you're
Speaker 1: at rest, especially if it's severe and keeps going for
Speaker 1: twenty minutes or longer. This is called unstable angina and
Speaker 1: requires immediate medical attention because it means the heart isn't
Speaker 1: getting enough blood to do its job period. Another thing
Speaker 1: that can go wrong with the plaque build up inside
Speaker 1: of your coronary arteries is sort of counterintuitive. You would
Speaker 1: think that if one of these obstacles broke open, that
Speaker 1: would be a good thing, but it can result in
Speaker 1: a blood clot forming at the sight of the rupture
Speaker 1: in the plaque. This little clot can totally block the artery.
Speaker 1: Within minutes, heart tissue downstream of the artery will basically suffocate,
Speaker 1: damaging the muscle. This is what's called a heart attack
Speaker 1: or myocardial infarction. Similar symptoms apply a discomfort or pain
Speaker 1: in the chest up through the jaw or down the
Speaker 1: arm or back, shortness of breath, weakness or dizziness, and
Speaker 1: sometimes a lot of nausea and sweating. And you probably
Speaker 1: know this, but I'm going to say it anyway, this
Speaker 1: is definitely a medical emergency, like to the point that
Speaker 1: you should call medical professionals to send you help right away,
Speaker 1: like dialing nine to one one instead of trying to
Speaker 1: get yourself to a doctor. All of this can be
Speaker 1: really scary, but there are lots of ways that healthcare
Speaker 1: providers can help get a dangerously blocked coronary artery up
Speaker 1: and running again. For example, Balloon angioplasty. This procedure uses
Speaker 1: a tiny medical grade balloon to open a clogged artery
Speaker 1: near the groin or in the arm. The provider accesses
Speaker 1: a blood vessel that leads to an artery that leads
Speaker 1: to the heart. They'll insert one or more wires and
Speaker 1: catheters and thread them up through the artery using special
Speaker 1: dye and an X ray machine. They'll find any blockages.
Speaker 1: Once found, they lead the catheter to the blockage and
Speaker 1: briefly inflate a tiny balloon on the tip to push
Speaker 1: the plaque aside and allow blood to flow more freely.
Speaker 1: This won't stop the arteries from blocking again, but it
Speaker 1: will help prevent an emergency and ease any discomfort that
Speaker 1: you're experiencing. Sometimes, in addition to or instead of an antioplasty,
Speaker 1: a metal or plastic tube called a stent may be
Speaker 1: inserted into a blocked artery to help prop it open.
Speaker 1: Doctors may perform angioplasty and stenting on a patient before, after,
Speaker 1: or during a heart attack. Some cardiologists prefer just stenting
Speaker 1: without angioplasty. The drawback of this procedure is that stents
Speaker 1: can clog just like your arteries. The upside to these
Speaker 1: procedures is that they're relatively non invasive. The patient can
Speaker 1: be awake, though mildly sedated. If things are a little
Speaker 1: more serious, a provider may perform what's called a coronary
Speaker 1: artery bypass graft. During this procedure, the provider temporarily stops
Speaker 1: the heart and sets up artificial respiration. A vainer artery
Speaker 1: that won't be missed too much is taken from somewhere
Speaker 1: else in the body, possibly your arm or leg. Surgeons
Speaker 1: attach one end of the graft to the a orda
Speaker 1: and the other end to the artery on the far
Speaker 1: side of the blockage. This detour enables blood to bypass
Speaker 1: the blockage and flow unobstructed. When you hear the terms double, triple,
Speaker 1: or even quadruple bypass surgery, it refers to the number
Speaker 1: of arteries receiving bypass graphs. Of course, these procedures are
Speaker 1: only part of a treatment plan for making sure that
Speaker 1: your hard working heart gets the blood supply that it needs.
Speaker 1: A health care provider may prescribe medications or recommend basically
Speaker 1: cardiac physical therapy in the form of exercise or changes
Speaker 1: to your diet or mental health care to help with
Speaker 1: anxiety and stress. As always, if you're concerned about yourself
Speaker 1: or a loved one, talking to a medical professional should
Speaker 1: be the first step. There's a lot of information and
Speaker 1: mis information out there about what's healthy, and they'll be
Speaker 1: able to help you personally, cut through the noise and
Speaker 1: keep that blood flowing. Today's episode is based on the
Speaker 1: article how and why does the heart pump blood to
Speaker 1: itself on how stuffworks dot com, written by Tom Sheeve.
Speaker 1: Brain Stuff is production of iHeartRadio in partnership with HowStuffWorks
Speaker 1: dot Com, and it is produced by Tyler Klang. Four
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