Tag Archive for: syncytium

Your Heart: Autorhythmicity

Your heart can beat over 200 times per minute during maximal exercise, depending on your age, yet every beat is a succinct event made up of many steps with every one of those beats controlled by the electrical system of the heart. While that’s incredible in and of itself, the real story is one of the most amazing features of your heart called autorhythmicity.

Your heart has a special area in one chamber that stimulates it to beat. It’s called the sino-atrial node (SA node) or the pacemaker. Think of that as the command center: it takes information coming from your body and sets the pace of your heart rate.

What you might not know is that some cells of the heart can stimulate themselves to beat. If something goes wrong with the electrical system for some reason, your heart can go right on beating because of the muscle make-up we talked about in Saturday’s Memo on syncytium. It lends itself to this autorhythmic feature. Think of it as the ultimate fail-safe system—makes you sleep a little easier, doesn’t it?

One more cool feature I’ll talk about on Saturday.

What are you prepared to do today?

        Dr. Chet

Your Heart: Syncytium

The next few Memos were from 2016 and are still relevant today! This is why your heart is special. Let’s begin American Heart Month with some facts you probably didn’t know about your heart. Your heart is unique in many ways, and you’re going to learn about a few of them.

The heart muscle is similar to skeletal muscle in the way it contracts, but that’s where the similarity ends. While skeletal muscle is laid out in parallel fashion and independent of one another, the heart muscle splits and connects to other fibers. In that way, every heart muscle cell connects to every other heart muscle cell, and that allows signals to be transferred very quickly. It’s referred to as a syncytium (pronounced sinˈsiSHəm) because it can act as a single unit.

But the heart must contract in specific locations at the correct time in order for blood to be pumped. The heart has to contract at the upper chambers first, the atria, and then the bottom of the lower chambers called the ventricles. That allows the blood to be pumped from the upper chambers to the lower, then from the lower chambers through arteries to the body.

Pretty cool, isn’t it? Wait until you read Tuesday’s Memo about the electrical system of the heart.

What are you prepared to do today?

        Dr. Chet

Your Heart and Syncytium

We’re finishing American Heart Month with some things you probably didn’t know about your heart. Your heart is unique in many ways and this week, you’re going to learn a few of them.

The heart muscle is similar to skeletal muscle in the way it contracts, but that’s where the similarity ends. While skeletal muscles are laid out in parallel fashion and independent of one another, the heart muscle splits and connects to other fibers. In that way, every heart muscle cell connects to every other heart muscle cell. That allows signals to be transferred very . . .

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