Tag Archive for: heart

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

Finding the Cause of Death

Last week, I left you with a question about a hypothetical situation: What if my grandmother’s bedsores had become infected to the degree that it spread throughout her body; she still had congestive heart failure but didn’t have pulmonary effusion at that time. What would be the primary cause of death?

With so many health experts and influencers that get a lot of attention in social media, causes of death appear to be misunderstood. Let’s cover it as simply as I can, based on the definitions from the CDC, WHO, and other agencies around the world.

  • The primary cause of death is the situation or condition that started the chain of events resulting in death.
  • The secondary cause(s) of death are any conditions that may have contributed to the death.

In the case of the hypothetical situation, the cause of death was the systemic infection from the bedsores. The congestive heart failure was a secondary cause of death. We can’t know for certain, but the infection probably took away the ability to fight back due to the weakened condition of the cardiovascular system.

I’ll give some examples of misinformation in Saturday’s Memo—which is May 10. Long time readers will understand the significance of that day.

What are you prepared to do today?

        Dr. Chet

Why My Grandmother Died

You may be wondering why the TAP-IT study created that stop-in-my-tracks moment. In the mid-1980s, my grandmother Frances was 80 years old and was always my biggest fan. She had congestive heart failure, so doctors tried the needle procedure, which drained close to 20 lbs. of fluid from around her lungs; you can imagine the pressure that caused on her heart. But congestive heart failure is an unforgiving disease—at least it was back then. Without a real treatment other than thoracentesis, there’s no cure.

Months later, the pulmonary effusion happened again, but she refused treatment because the procedure had hurt too much the first time. She died a couple of weeks later. The study prompted my realization that a medication like a diuretic might have prevented a rather difficult death with multiple bedsores.

The fact that there was never a randomized controlled trial to compare the two approaches until 45 years later just absolutely astounds me. At least now there are treatment options for people with the same condition without the same type of complications.

Just to be clear: there was no coming back from advanced congestive heart failure as my grandmother had. Using either procedure would not have cured her—it would have eventually killed her anyway. But the difference was really in her quality of life. She may have lived longer and certainly less painfully using the diuretic, which as I said was available even back then. But there was no research to support it.

What Was the Cause of Death?

There appears to be a lot of misinformation today about cause of death. I’m going to use my grandmother as an example. I mentioned that she had severe pulmonary effusion due to the congestive heart failure. But she also had bedsores. If they had gone septic, resulting in a whole-body infection, what would have been the official cause of death? That’s what we’ll explore next week. Please share your thoughts.

What are you prepared to do today?

        Dr. Chet

Reference: Circulation. 2025 Apr 1;151(16):1150–1161

TAP-IT to Stop It

Have you ever had a moment where you were reading something, listening to an audio, or watching a video where you just had a moment of realization and absolutely stopped in your tracks? The reason is that you got hit with a discovery of some fact that you didn’t know. More than that, you realized what it meant. That’s what happened to me while listening to a podcast from a cardiologist about pulmonary effusion and how to treat it.  Let’s start there.

Pulmonary effusion (PE) is the buildup of fluids in the connective tissue surrounding the lungs and the chest cavity.  If enough fluid builds, it’s going to push on the lungs and ultimately push on the heart and make it very hard to breathe. To restore function, the fluid has to be removed. This happens to people who have congestive heart failure.

The TAP-IT study, formally called Thoracentesis to Alleviate Cardiac Pleural Effusion–Interventional Trial, was recently published in a leading heart journal. The researchers selected subjects who were 80+ years of age with less than a 25% ejection fraction. This population was chosen because they are the ones most likely to suffer from pleural effusion. They compared subjects who took diuretics to alleviate the fluid with subjects who got thoracentesis. The goal was to determine if there were any differences in outcomes as assessed by the number of days lived after beginning treatment.

The results? There were no differences in outcomes between the two groups. That’s amazing! Both reduced the pleural effusion, but there were differences in patient comfort and quality of life. As you might imagine, sticking a 2- to 5-inch needle through the rib space and into the pleural cavity to drain the fluid is going to be uncomfortable if not downright painful. There were also 20 out of 80 pneumothoraxes with the needle approach, while there were no complications noted in the group that took the medication.

The realization? This was the first randomized controlled trial that compared thoracentesis with diuretics, even though diuretics have been available for 75 years and thoracentesis for 175 years! Why did that matter to me? I’ll tell you on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: Circulation. 2025 Apr 1;151(16):1150–1161

Exercise Your Heart, Part 2

Did you ever have to hurry to catch a connecting flight? Walk fast or maybe even jog? Were you able to do it?

How about carrying a child who weighs 45 pounds for a quarter mile because she’s hurt her foot? Could you do it?

That’s where your heart reserve comes in: facing challenges that put your heart to the test. Everyday training helps, but getting fitter is also important for those occasions when you need more. If your physician says you can do it, interval training is the solution to building a reserve.

Intervals have been around for decades, and they became a fad with something called High Intensity Interval Training (HIIT). They’re the same thing except that HIIT is supposed to replace all other aerobic exercise to save time. I’m sorry, but it’s just not enough. Doing well on a fitness test isn’t the same as living.

The idea is to exercise as fast as you’re able for 30 to 60 seconds, then rest for one or two minutes, sometimes even more. Repeat the cycle eight to twelve times and you’re done. For some people, walking faster for 30 seconds is enough; for others turning up the intensity on a bike to the highest level for 60 seconds would be the intensity. It doesn’t matter your level when you begin; it will help you build a reserve for challenges. That’s something we all need. Again, you have to check with your physician before exercising to build a baseline or a reserve. It’s one of the keys to living every day.

Think we’re done with exercise? Nope. We’ll turn to those other muscles next week.

What are you prepared to do today?

        Dr. Chet

Exercise Your Heart, Part 1

In my opinion, the single most important thing you can do to be able to live life at your best is to exercise your heart. Every day. You don’t have to run marathons; you don’t ever need to run at all. You just need to train your heart every day. I’ve broken it down into two components that I’ll call baseline and reserve.

The aerobic baseline for your heart is just that: the level of fitness you need to accomplish every day tasks. The baseline will be different based on your age, your initial fitness level, and what your everyday activities are. That’s as simple as walking across a room and as challenging as being a laborer on a construction site or moving furniture up five flights of stairs.

If there are no orthopedic issues, the simplest exercise is walking or it could be long-distance running or bike riding. The goal is to get your heart rate elevated enough to cause the heart to beat faster than it does when resting. That trains the heart in more ways than I can explain.

The simplest way to describe how to do it’s this way. Walk fast enough so that you have to take a deep breath once in a while but you can carry on a conversation. If you can’t talk, slow it down. But if you can sing, that’s too slow. You can use that across every aerobic type of exercise from aerobics to Zumba. The goal is at least 30 minutes most days of the week.

You also need a reserve and I’ll talk about that on Saturday.

What are you prepared to do today?

        Dr. Chet

Do You Make Enough Coenzyme Q10?

There’s one major difference between coQ10 and other vitamins, minerals, and nutrients such as omega-3s: we can produce coQ10 ourselves. The problem is that we may not produce all the coQ10 we need, especially as we get older.

CoQ10 is used in the production of energy from both carbohydrates and fat in the mitochondria of the cells. You remember mitochondria from science class; they’re often called the powerhouse of the cells. And coQ10 is the substance that’s used to produce that power. It’s critical in the steps where oxygen is used to produce ATP, the . . .

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