From orange juice, to a ripe tomato, to your new girlfriend; everyone loves a good squeeze. But these three delectables are not your MAIN SQUEEZE. Squeezing your own heart is something you do about 60 to 100 times per minute, every minute, from before you are born until the moment you die. If you can't imagine how you are squeezing your girlfriend and squeezing your own heart at the same time, then now is a good time for some anatomy of the heart.


Instead of trying to conjure up the image of an icky, gooey, bloody blob of organ meat, it may help to start off imagining that the heart is kind of like a Highlander's bagpipe. It's a hollowed out bag with pipes emerging out of it, through which something flows. Doesn't that sound nicer? The anatomy of the heart can be boiled down to the SIX-P's….


1. The (Chamber) Pot


The indoor toilets of yesteryear were simply vessels that held fluid---Let's not go there with the solids. The heart is a four-chambered pot, but more like a bag, albeit a very muscular bag. Blood flows from one chamber to another, picks up oxygen, flows back into another chamber and then out through the body.

heart anatomy

Image by Blausen Medical Communications, Inc. [CC BY 3.0], via Wikimedia Commons

The anatomy of the heart includes a barrier called the septum. It is a wall of tissue that divides the right and left ventricles, prevents the co-mingling of oxygenated and de-oxygenated blood, and houses electrical pathways.

No Choosing Sides: The Chambers

Two different views of the anatomy of the heart

Image by OpenStax College [CC BY 3.0], via Wikimedia Commons

The top two chambers are situated on the north side of a division from the bottom two chambers to the south, but they all pump the same blood. Although the two chambers to the right receive and send blood to different places than the left 2 chambers, all four work together to send de-oxygenated blood through the lungs and push oxygenated blood out into the body.


The Atria

Each upper chamber of the heart is called an atrium, and just like an atrium in a building, it is an open space. The atria are a bit lame in their squeezing action; although they contract, they don't have the same force as their macho southern brothers. Despite such an inviting locale, you don't want your blood lounging around and clotting.

The Ventricles

ventricles of the heart contracted

Image by Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436. [CC BY 3.0], via Wikimedia Commons

The Ventricles are über muscular (No, not the beefcakes in the taxi) chambers that do the hard squeezing. They do more exercise in a matter of minutes than some people do in a week.

The Right Atrium And Right Ventricle

The right atrium takes in blood that unloaded its oxygen supply as it cruised through the vascular system of the body. It pushes that blood out through an opening and into the right ventricle. The right ventricle squeezes that out-of-breath blood into the pulmonary system (lungs), where it loads up with tons of oxygen.

The Left Atrium And Left Ventricle

The left atrium receives blood that is packed with oxygen and drains it into the left ventricle. The left ventricle --- the true powerhouse ---then shoots oxygenated blood up and out into the body like a fire hose on fire.

blood flow through the anatomy of the heart

Image by National Institutes of Health [Public domain], via Wikimedia Commons


1. Doe-Si-Doe: The Eternal Square Dance

Are you ready square dancers? Let's take it from the top!

De-oxygenated blood from the body enters the right atrium. The right atrium fills and drains into the right ventricle. The right ventricle fills with blood and squirts it into the lungs, where the blood picks up oxygen. 

Oxygenated blood then pours into the left atrium. When the left atrium is full that blood is sent to the left ventricle; the left ventricle then ejects oxygenated blood out into the hungry body.

Around and around the dance floor you go. This dance goes on from before birth until death—Your Personal Eternity.

2. The Pump

water pump

Image via Pixabay


No, silly, not that kind of pump! The heart's pump uses pressure differentials and muscle power to move blood through the chambers and out into the body. Every time the heart beats the two ventricles squeeze or contract, while the two atria relax and fill. The atria contract prior to ventricular contraction and this timing delay allows for the chambers to adequately fill with blood.

The Heart Is A Muscle

The anatomy of the heart includes exclusive designer features. Cardiac muscle tissue is only found in the heart. Muscle fibers are connected at the ends by little doodads called intercalated discs, and this is what allows the cardiac muscle to contract in a wavelike fashion.

cardiac muscle tissue close up

Cardiac (heart) muscle image by OpenStax College [CC BY 3.0], via Wikimedia Commons

Cardiac muscle is responsible for the contraction and relaxation of the heart. More than that, it has to have enough power and energy to eject blood with enough force to feed the waiting masses (organs and tissues). 

During a heart attack, muscle tissue is deprived of oxygen and begins to die; the damage depends on how severe the heart attack and how long the deprivation. Dead heart tissue = useless heart tissue = broken pump; how broken depends on the severity and duration of the damage.


3. The Police

Well, so what keeps the blood flow from going in the other direction? There must be some kind of police to keep order. 

Is there some kind of hematologic dominatrix with a black leather whip maintaining dynamic discipline? No, there are 4 heart valves that prevent blood backflow.


The Valves

heart valves

Image by OpenStax College [CC BY 3.0], via Wikimedia Commons

There are four heart valves:

  •  The tricuspid valve
  • The pulmonic value
  •  The mitral valve
  • The aortic valve

The tricuspid valve prevents backflow of blood from the right ventricle into the right atrium. It has three leaflets or flaps.

The pulmonic valve lies between the right ventricle and the pulmonary system. It has three cusps.

Pulmonary valve

Image by Mariana Ruiz LadyofHats [Public domain], via Wikimedia Commons

The mitral valve, like its brother in the other atrium, has 2 flaps. It lies between the left atrium and the left ventricle. It has the pressure from that muscle-bound left ventricle to contend with.

Not to show favoritism, but the aortic valve has perhaps the biggest job of all. It opens to allow the oxygenated blood from the ventricle to shoot out into the rest of the body, and it has to close in enough time to prevent backflow.


valves of the heart

Image by National Heart Lung and Blood Institute (NIH) [Public domain], via Wikimedia Commons


Cat Flap, Toilet Flap, Flappin' In The Breeze

Cat looking through cat flap in door

Image via Pixabay

Heart valves are not like cat flaps; they only open one way. When any of the heart valves fail to close tightly, a condition called regurgitation occurs. Some of the blood that is ejected through the valve flows back into the originating chamber. This is when symptoms occur such as:

• Exertional fatigue and weakness
• Shortness of breath
• Swollen ankles and feet
• Chest pain
• Lightheadedness or fainting
• Dysrhythmias
• Heart murmur

When the valves become narrowed, the amount of blood that can get through is reduced, and the heart is forced to work harder and weakening the heart. Symptoms of valvular stenosis include:

• Abnormal heart sounds
• Chest pain
• Dizziness
• Shortness of breath
• Fatigue
• Dysrhythmias
• Failure to thrive

There are congenital heart valve diseases, which means you are born with them. The valves may be the wrong size, malformed or incorrectly attached. Bummer.

Heart valves may be likened to the flapper in your toilet tank. The pressure and volume of blood rushing into a relaxed (non-contracting) chamber keeps the valve closed until the pressure (not only against the walls of the chamber but pressure from a heart contraction) and volume forces it open. 

Heart valves may be likened to the flapper in your toilet tank. The pressure and volume of blood rushing into a relaxed (non-contracting) chamber keeps the valve closed until the pressure (not only against the walls of the chamber but pressure from a heart contraction) and volume forces it open. 

While chamber one (an atrium) has been relaxing and filling, the chamber below it (a ventricle), has been contracting and ejecting blood out through its respective valve. When there is no more ejecting blood forcing the valve open, the valve closes as the pressure declines; it's all about the force of contraction and the pressure gradient.

Listen To Your Heart

No, not that song by Roxette. Put your ear down on the chest of your favorite (or wannabe favorite) squeeze and listen to their heartbeat. Better yet, find a stethoscope, plug it into your ears and put the diaphragm (that little round thing at the end) over your own heart and just listen. That Lub-Dub sound is proof that your heart valves are opening and closing.

heart and earbuds

Image CC0 via pxhere

4. The Power

Well, so what powers the pot and the pump and the police? There, within the anatomy of your heart, lies an awesome electrical system. The system controls the timing of your heartbeat by regulating your rate and your rhythm and initiating a chemical wave of electrical impulses from your right atrium, down through conduction pathways and causes the ventricles to contract.

Electrical system of the heart

Image by OpenStax College [CC BY 3.0], via Wikimedia Commons

Nod​​​​es, Bundles And Other Doodads


The electrical activity in the normal heart is initiated by 2 specialized knobs of tissue called nodes; these are the pacemakers of the heart. The SA node is embedded in the right atrium, starts the spark and establishes the rhythm. The AV node dwells in the border between the atrium in the ventricles. The atria then contract in their rather lame way.

After a brief delay at the junction between the atrium in the ventricles, the electrical activity travels through a conduction pathway called the Bundle of His and into the ventricles. The Bundle of His then divides into right and left cables called Bundle Branches; the bundle branches have little shoots called Purkinje fibers. Once the electricity reaches the ventricles, they squeeze.


Each squeeze= one heartbeat. The anatomy of the heart is beautifully efficient.

system of the heart

Image by Madhero88 (original files); Angelito7 (this SVG version); [CC BY-SA 3.0], via Wikimedia Commons

Heartstrings

Your favorite squeeze or a sad movie might tug at your heartstrings, also known as the chordae tendineae.  These stringy, and bundled fibers are not only part of a never-ending cycle of electrical activity, but they have their own intrinsic heart rate, should your heart's own pacemakers fail to fire off  like they should.

Hand holding heart

Image by OpenStax College [CC BY 3.0], via Wikimedia Commons

​Eurhythmics

Yes indeed, sweet dreams are made of this: harmonious, pleasing, normal heart rhythms. When the heart beats faster than usual, it may be that you are exercising or putting the squeeze on a new girlfriend. When your heart beats too fast, too slow or irregularly, you will need to have it checked out if it is persistent and if it causes you to have symptoms. 

The types of arrhythmias are:

  • Atrial fibrillation
  • Bradycardia
  • Conduction disorders
  • Premature contractions
  • Tachycardia
  • Of ventricular fibrillation
  • Other rhythm disorders
  • Pediatric arrhythmias
heart arrhythmias

Image by CNX, CC by 3.0, via Wikipedia Commons

The symptoms of arrhythmias include:

  • A fluttering in the chest
  • A racing heartbeat
  • A slow heartbeat
  • Chest pain
  • Shortness of breath
  • Lightheaded or dizziness
  • Sweating
  • Fainting

If you are not sure if that funny feeling or discomfort in your chest is due to an arrhythmia, contact your physician, or you can get information from the American Heart Association.

If you are significantly symptomatic and it's not a higher-than-normal heart rate due to usual activities such as exercise; if it feels like you're going to faint or you have chest pain, DIAL 911. There are some cardiac arrhythmias that are lethal--- ventricular fibrillation will take your life unless cardiac life support maneuvers are initiated immediately.

5. The Pipes

The Pot, the Pump, the Police, and the Power source all work together to take in the de-oxygenated blood, load it up with oxygen and move it out into the body. 

The anatomy of the heart includes arteries that send oxygenated blood out from the heart and into the body and veins that bring deoxygenated blood from out in the body, back into the heart. 

The exception to this occurs in the pulmonary system. The pulmonary artery is fed deoxygenated blood coming from the right ventricle. The pulmonary veins send oxygenated blood from the lungs to the left atrium.

When these blood vessels become narrowed with cholesterol induced plaque or from other pathological processes, blood flow is a no-go. If a blood clot or any other kind of clot breaks off, escapes from its moorings and completely blocks an artery, blood flow becomes a no-show. The type of tissues (heart, brain, lung, legs) that are fed through the clogged artery will determine what functions will be impaired, if not lost.

Arterial plaque buildup

Image by National Heart Lung and Blood Institute (NIH) [Public domain], via Wikimedia Commons

6. The Pig Out

Two man eating pizza

Image via Eglin AFB, USAF, CC0

A guy's gotta eat to keep goin', right? The heart requires a food supply as well. The largest artery in the body is called the aorta; it is fed by the left ventricle. Some of the blood that comes rushing out of the heart gets diverted to the heart muscle itself. Even the heart likes to chow down.

Feed Thyself

Right out of the chute, the aorta branches off into the right and left coronary arteries. These arteries are the ones that feed the heart itself. They then further divide into smaller arteries:

• Left anterior descending artery (LAD)
• Left circumflex artery
• Left marginal artery
• Left anterior descending
• Right marginal artery
• Right posterior descending artery

Don't worry about each and every offshoot from the left and right coronary arteries, because clots that occur above the little guys are going to block blood flow to them no matter what. Once again, the damage, e.g., a heart attack, all depends on location, the severity of blockage and duration.

The Good, The Bad And The Ugly

The Good

The anatomy of the heart is an awesome thing.

It is astonishing when you think of how the 6-P's:

• The Pot- a bag of chambers
• The Pump-heart muscle
• The Police-the valves
• The Power-the electrical system
• The Pipes-the blood vessels
• The Pig out-the self-feeding coronary arteries

model of the anatomy of the heart

Image via Pixabay

hands showing teamwork

Image via Pixabay

All work together to generate the 7th-P--- the PULSE. And they do so from before you were born until the moment of your death. Let's see you and your co-workers work that well together for even 10 minutes.

The Bad

Some of us are born with bad hearts; there will be problems no matter how we live our lives. Some of us have heart problems inflicted upon us, such as a gunshot wound or a knife through the heart. But the biggest cause of a bad heart is because of the things we do and put into our bodies over time, AKA our lifestyle.

drunken stuffed animal

Image via Pexels


The Four B's: Booze, Benzedrine, Barbecue and Babes

hippies halloween costume

Image via Pixabay

For us baby boomers, those born between 1946 and 1961, many of us drank booze until our faces went numb on a regular basis. Some may have even had a fairly steady diet of prescription drugs, many of which are no longer on the market because they're so bad for you.

We ate all the artery clogging, artificially colored, artificially flavored, sodium saturated, and nitrate soaked foods we could shove into our pie holes. We spent so much time squeezing the tomatoes that we chronically failed to get enough sleep.

Younger generations have learned from baby boomer mistakes and, with the help of modern research, are more health conscious. 

The anatomy of the heart often runs in families. That means that some of us inherit bad genes or predispositions for heart problems.

There are some people whose luck and genetics makes them bulletproof, and there are those lifelong health fanatics that drop dead of a widowmaker heart attack at the age of 35. Go figure.


Healthy senior citizen setting on the rock

Image CC0 via Pixabay

The Ugly

The ugliest part of the heart is the hospital bill that comes after poor heart health catches up with us. It's never too late to begin living a healthy lifestyle, and it's never a bad thing to start. If you can make one change at a time, then you are doing better than you did the day before. Some changes you can make are:

• Control your blood pressure
• Control your cholesterol and triglycerides
• Stay at a healthy weight
• Eat a healthy diet
• Get regular exercise
• Quit smoking
• Reduce stress

Man holding a wallet

Image via Pexels

You can get advice from the Mayo Clinic, or you can search the web for something that might work for you. Don't give up, no matter how often you get down, and just live one day at a time.


Anatomy Of The Heart

human heart rhythm

Image via MaxPixel

Unlike your favorite squeeze, your pump won't dump you when you're down. It will only desert you if you have gone too far for far too long with the Four B's, and all the other things that are so good and so bad for us.

Everyone loves a good squeeze, but your main squeeze is your OWN HEART.

Your heart puts up with you no matter what. That makes it your BRAVEHEART.

Year after year, your heart just keeps on beating. That makes it your TRUE HEART.

But never ever forget that it is also your ONLY HEART.


Featured Image; CC0 via Pixabay

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