Heart Function – Beyond Flowers and Candy
The Heart: a symbol of love and deep emotion in our lives…much written about, dreamed of and so many stories attributed to this part of the human body. The physical organ, on the other hand, is not so romantic, but just as important to understand.
“The heart is like an electrical circuit… it is simply electrical impulses. One substance tells it how frequently to beat, and another tells it how hard to pump. If one is deficient, the electricity doesn’t flow and heart problems happen. Both are easy to fix.”
When a well-respected naturopath said this, my mouth fell open. So many heart diseases in the world, and yet he summed it up in two little substances that get out of balance. Having dealt with heart flutters frequently, I was deeply intrigued to understand if the heart was truly this simple. So I dug into researching the most important organ in our body… the heart.
For a refresher from biology class:
- The heart has four chambers. The upper two chambers are called atria, (right and left atrium,) and the two lower chambers are called ventricles, (right and left ventricle).
- The heart beat starts as an electrical impulse in the right atrium in a group of special cells called the sinoatrial, (or sinus) node. This is the pacemaker for the heart.
- The “pacemaker” cells send out an electrical signal that spreads throughout the heart along electrical pathways. These pathways transmit the signal from the upper to the lower chambers of the heart, which causes the heart muscle to contract and direct blood through each chamber in turn. Regular, rhythmic electrical signals keep the heart pumping blood from lungs to the rest of the body.
Electrolytes are substances that, when placed in water, can carry an electrical charge. Electrolytes are required for nearly every physiological function, such as maintaining water balance in cells, making enzymes, and creating energy. Three of the most important electrolytes in cell function are potassium, magnesium and sodium. The kidneys tightly control their relative ratios in the blood.
The heart is extremely sensitive to electrolyte balance since its rhythm is indeed controlled electrically. An excess of any one electrolyte can produce inequalities between the cell’s interior and exterior electrical charge, resulting in electrical disturbances across the cell membrane.
Potassium directly impacts the heart’s rhythm. Potassium concentration affects both the heart’s electrical system and the heart muscle directly. When serum levels of potassium fall below 3.5mEq per liter, cardiac cells start to become electrically unstable and begin to palpitate. When levels of potassium fall below 2.5 mEq per liter, the electrical effect on the heart can be dangerous. Too much potassium can cause the heart to fibrillate, which means the heart’s electrical system is out of synchrony, causing rapid and irregular beats. To reestablish normal rhythm, replace the potassium electrolyte intravenously or orally as quickly as possible, taking care not to add too much. As a word of caution, many people who are taking diuretics, or “water pills”, are reducing the amount of sodium and potassium in the body.
It’s very important to have a proper balance between magnesium and calcium, but few people get enough magnesium in their diet these days. Insufficient magnesium tends to trigger muscle spasms, and this has consequences for your heart in particular.
As explained by Dr. Carolyn Dean, author of the seminal paper “Death by Medicine” in 2003 and the book, “The Magnesium Miracle,” your heart has the “highest magnesium requirement of any organ, specifically your left ventricle. With insufficient amounts of magnesium, your heart simply cannot function properly. Hypertension (high blood pressure), cardiac arrhythmia,11 cardiovascular disease (CVD) and sudden cardiac death are all potential effects of magnesium deficiency and/or a lopsided magnesium to calcium ratio.”
Sodium is often the vilified electrolyte. Too much sodium consumption can increase blood pressure and cause the body to hold onto fluid. High blood pressure (hypertension) is a major risk factor for heart attack, stroke and other cardiovascular problems.
However, too little sodium is a problem as well. A low sodium level has many causes, including consumption of too many fluids, kidney failure, heart failure, cirrhosis, and use of diuretics. One review of controlled trials found that for people with heart failure, limiting sodium intake increased the risk of dying. In fact, people who restricted their sodium intake had a 160% higher risk of death. Some studies have also found that low-sodium diets may increase both LDL cholesterol and triglyceride levels.
The most important thing to remember is that the heart is an electrical functioning organ and needs a tightly controlled environment to do its job properly. While our bodies are extremely resilient, keeping electrolytes in balance, and in the right ratios, are critical for these key electrical impulses to operate in time and in tempo. And while it may not be romantic, it will keep this critical organ primed for those pitter-patter moments well into our golden years.