Why should you invest a few precious heartbeats in learning something about your ticker?
Because of and heart attacks – and because in this country.
photo © 2009 | (via: )
Most of us think the heart is the most important organ in your body. While this might spark a heated philosophical debate, the heart has a certain anatomic primacy based on the simple fact you can’t live without it, even for a few minutes. And few things will ruin your day more.
Most of the important organs in your body are designed with a certain redundancy, like airplanes having two spark plugs per cylinder. You have two kidneys, but can get by on one. You can lose more than half of your liver, just as much of your intestines, blood or lungs, and live, although not with all of that occurring simultaneously. Running on 50 percent function of most organs will leave you alive to fight again.
Ah, but the heart – there can be only one.
Conceptually, the . It’s a variable speed pump. The faster it beats, the faster the blood goes round and round. It is actually kind of a double pump – one side pumps blood to the lungs, the other to the body. You have to be impressed by the build quality. Most hearts are good for 70+ years and more than 50 million cycles. Very few other things in the world, either living or inanimate, last 50 million cycles.
The heart is a lot like other pumps you know. Pumps, in general, don’t run on what they pump. Think about it – the oil pump in your car uses electricity to pump oil, and a pool pump uses the same to pump water. Similarly, the heart is not nourished by the blood inside the pump; rather, it is powered by the blood in vessels on the outside, namely the coronary arteries.
Given the coronary arteries’ well known propensity to plug up, perhaps the heart might have been better designed to get its nourishment from the blood inside.
But there are sound mechanical reasons why this can’t be. The first involves the heart’s thick muscular walls. There is no way for oxygen to passively diffuse across dense heart muscles in enough concentration to keep the heart alive, let alone beating.
Then there is the problem inherent in that whole beating thing. Blood leaves the heart in an intermittent flow (squirt-stop-squirt-stop). Most tissues, including the heart, don’t tolerate this type of flow. They need continuous flow. Getting this flow smoothed out is the job of the major arteries. These arteries have muscular walls that act as shock absorbers. They expand to absorb a slug of blood and then steadily contract to keep it moving. This works much like a water reservoir supplying water continuously to a town, even though rain is episodic.
Ah, but a heart is so much more than simple plumbing.
A . Heart cells are a type of muscle cell, and like muscles everywhere, they contract. A specialized group of heart cells is a built-in pacemaker. This supplies the tempo. Everybody has to contract at once to get anything done. When they don’t, the heart sort of quivers and stops pumping, and that’s bad.
There can be either blood flow problems, rhythm problems or both from similar things. Atherosclerosis, or plugged coronary arteries, starves the heart cells. Sometimes these cells curl up and die. Sometimes they go electrically haywire and a rhythm disturbance occurs.
So the most important care and feeding of your heart are keeping good freshly oxygenated blood flowing through your coronary arteries. You have been prewired for this to happen. All you have to do is not screw it up. To do this simply means don’t do the stuff that clogs arteries.
• Do control your blood pressure
• Do control you weight
• Do control your cholesterol
• Do control your sugar if you have diabetes
• Do control your stress
• Do not smoke
• Do laugh as often as possible; it helps immunize against stress
• Do drink some red wine – it’s good for your heart and might also help with stress
• Do get some exercise, and for heaven’s sake, don’t suffer for it. If you do, the stress might cancel the benefit of the exercise.
So while hearts may continue to be a mystery to young lovers, you now have the necessary information to understand what makes them tick.