Cardiac Physiology Walkthrough

Cardiac physiology is the study of how the heart works. It looks at how the heart pumps blood, controls blood flow, and keeps the body’s blood moving. This study helps us learn about the heart's electrical and mechanical activities.

The heart's main job is to pump blood around the body. This helps give oxygen and food to the body and takes away waste like carbon dioxide. The heart does this by squeezing and relaxing its muscles in a special order.

Here are some tools and techniques that might help understand better:

• Use Pictures: Look at pictures of the heart and how it works.
• Watch Videos: Watch videos that explain the heart in simple ways.
• Ask for Help: Ask a teacher or adult to explain it to you.

The heart is like a pump that moves blood around your body. It does this by beating. The heart has four rooms called chambers. The top rooms are the atria, and the bottom rooms are the ventricles.

When your heart beats, blood moves from the atria to the ventricles. Then, the ventricles push the blood into the arteries. This happens when the heart squeezes, which is called systole.

When the heart relaxes, called diastole, it fills up with blood again.

If you find this hard to read, you can use tools like text-to-speech apps to listen to the words. You can also ask someone to read it with you and explain if you have questions.

The SA node is a special part of the heart. It is in the top right part of the heart. It helps the heart beat in a steady way. It sends out tiny electric messages. These messages tell the heart to beat. First, the top parts of the heart squeeze. This pushes blood into the bottom parts of the heart.

The AV node is like a tiny gate between two rooms in the heart: the atria and the ventricles. It helps control the signal that tells the heart to beat. The AV node slows down this signal so the atria have time to squeeze and push blood into the ventricles before the ventricles squeeze.

If you need help understanding this, try using pictures of a heart to see where the atria and ventricles are. You can also use apps or websites that show how the heart beats. Taking a deep breath and reading slowly can help too.

The heart has two main jobs. First, it squeezes to push blood out. This is called systole. Then, it relaxes to let blood in. This is called diastole. These jobs keep blood moving around the body.

Tip: You can use pictures or videos to help understand how the heart works. There are apps that show the heart beating in slow motion. These can help you see what happens during systole and diastole.

The heart pumps blood every minute. This amount of blood is called cardiac output. It is important because it shows how much blood, oxygen, and food reach the body. To find cardiac output, we multiply how fast the heart beats by how much blood is pumped each beat.

Your heart beats faster or slower because of different things. These things include moving around, how you feel, how hot or cold it is, how you are sitting or standing, medicine you take, and how healthy you are.

A part of your body called the autonomic nervous system helps control your heart rate. One part, called the sympathetic system, makes your heart beat faster. Another part, called the parasympathetic system, makes your heart beat slower.

Here are some tips to help if you’re trying to understand this better:

• Take deep breaths to help calm your heart rate.
• Try moving to see how it speeds up your heart.
• Check if you notice changes when you’re excited or scared.

The Frank-Starling law explains how the heart works. It says that the heart pumps harder when its walls stretch more. So, if the heart fills up with more blood, it can pump more strongly.

To understand this better, think of it like a balloon. If you blow more air into a balloon, it stretches, and when you let go, it pushes the air out quickly. The heart works in a similar way with blood.

If you need help with reading, you can use tools that read out loud or apps that highlight words. These tools can make reading easier and more fun!

Blood pressure is how hard your blood pushes against the sides of your blood tubes. It shows how hard your heart is working to move blood around your body. It is important to know your blood pressure because if it is too high or too low, there could be problems with your heart.

The coronary arteries are like special roads that bring oxygen-rich blood to the heart muscle. The heart works all the time, so it needs a steady flow of oxygen and food from these arteries to keep working well.

An electrocardiogram, or ECG, is a test that checks how your heart is working. It looks at the electrical signals your heart makes. An ECG can help doctors see if your heart is beating normally, if there has been a heart attack, or if there are any problems with how your heart is built or how it works.

Heart valves help blood move the right way through the heart. They open to let blood go forward and close to stop it from going backward. The four main heart valves are called mitral, tricuspid, aortic, and pulmonary.

To help understand better, you can use pictures or diagrams of the heart. Watching videos about how the heart works can also be helpful.

The myocardium is a special muscle in the heart. It helps the heart pump blood all around the body. This heart muscle is strong and can keep working without getting tired.

Here are some tips to help understand this better:

• Think of the myocardium as the heart's "super muscle."
• This muscle works like a pump to move blood everywhere.
• Even though we rest, the myocardium keeps working hard.

Use pictures and videos to see how the heart works.

Exercise helps the heart work better. It makes the heart muscle stronger and helps the heart pump more blood. This makes blood flow better around the body. Doing exercise often can make your heart stronger, lower your heart rate when you are resting, and make you less likely to get heart problems.

To help understand this better, you can use pictures and videos. Listening to audio explanations or using apps that read text out loud can be helpful too.