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The Rhythm of Life

A human heart beats over three thousand million times in the average lifetime. Beating at around seventy-two beats every minute, it pumps some 220 million litres of blood.

The regular rhythm of your heart is controlled by a tiny built-in pacemaker that produces electrical impulses which stimulate the heart muscles. This tiny control centre has elaborate feedback mechanisms which enable it to adjust your heart rate to suit your level of activity.

If your natural electrical signals are disturbed by heart disease, or if the worst happens and the impulses shut down, we can apply external electrical stimulation to restart the heart. Then we can use a pacemaker to maintain its life-sustaining rhythm. If needed, a permanent pacemaker can be implanted under the skin, with wires, connected to small electrodes attached directly to the heart wall.

The pacemaker is a miniature generator, powered by tiny batteries, which can last over ten years. The rhythm is usually set to maintain around one beat per second, slightly slower than the average heart beat. The pacemaker is designed to function only when the heart is not producing its own electrical impulses at correct intervals. By detecting delays and filling in the gaps, it ensures that the heart maintains a normal rhythm.

So next time you feel your heart throbbing, give some credit to the wonderful natural pacemaker that controls it.

Anything that might interrupt the regular beat and rhythm of our heart is potentially life threatening. An interesting study released by Johns Hopkins Medical Centre, on February 9, 2005, found that sudden emotional stress can lead to what is called, stress cardiomyopathy or “broken heart syndrome.” Patients were misdiagnosed with what appeared to be a heart attack when they had actually suffered from surges in adrenalin and other stress hormones that temporarily stun the heart.

The type of emotional stress that leads to broken heart syndrome includes grief, car accidents, fierce arguments and even surprise parties. In some people, the body responded by releasing chemicals which produced symptoms such as chest pain, shortness of breath and heart failure. But, the good news is, in these cases of broken heart syndrome the damage to the heart muscle is reversible. Patients who were hospitalized recovered in just a few days with little more than bed rest and plenty of fluids and no doubt plenty of love and understanding.

Our hearts are delicate, requiring both wisdom and sensitivity as we look after our bodies and do what we can to protect ourselves emotionally so that we don’t suffer from a broken heart. The condition of our heart is so important to God that the word appears almost 800 times in the Bible. In Psalm 34:18 we read, “The Lord is near to those who have a broken heart.” So even though this new syndrome was recently diagnosed by the doctors at John Hopkins, the One who formed our heart knew it could be broken.

During those desperate times in life when our hearts ache with the unexpected loss of a loved one or the breach in trust of a close relationship, God is near. He will be our pacemaker, sustaining the beat and rhythm of a broken heart. He is as close as a whispered prayer, grieving with us with each tear we shed. And just like the patients studied by John Hopkins the rest, love and understanding bestowed upon us by our heavenly Father can heal our aching wounded heart. His promise to do this for us is found in the second half of Psalm 34:18, “(He) saves those who are crushed in spirit.”

David Humphreys and Deborah Piggott
© August 2004