Frank Starling and the Heart

This is a very superficial explanation of the Frank-Starling Law (FSL) as it relates to the heart. You can find more information by doing a simple internet search. Not many people have heard of the Frank-Starling Law. Or if they have, they’ve probably forgotten it. That’s too bad, because the Law speaks a lot for sudden and special creation vs. evolutionary change. The FSL recognizes that when certain muscle fibers are stretched, they recoil in proportion to their stretch. Think of a rubber band. Stretch it in you hands a few inches and let it go. It recoils only a little bit. Stretch it as far as you can without breaking it, and it snaps back hard enough to sting your fingers. The FSL depends on an extraordinarily complex interaction of
calcium and other electrolytes with specially designed muscle fibers. Without even one of the dozen or so critical elements responsible for muscle fiber recoil, the entire Law falls apart. That is an important point. Cardiac muscle fibers function according to the FSL. When the volume of blood flows into the bottom chambers of the heart (the ventricles) the ventricular muscles stretch in proportion to the volume, and then snap back to propel blood out of the heart and into the rest of the body. Blood pumped out of the heart is called “cardiac output.” Thus, the greater the stretch (within physiological limits), the greater the cardiac output. Anyone with a medical condition that causes a reduction in cardiac output knows how quickly he or she can get out of breath. For some people, simply walking from the couch to the bathroom can be a breathless ordeal. Furthermore, and more serious, without efficient cardiac output, blood backs up in the veins leading from the lungs to the heart – kind of like a traffic jam on the interstate causes backup of vehicles sometimes for miles. When blood backs up from the heart to the lungs, pulmonary (lung) congestion occurs. If not corrected, the person will drown in his or her own bloody fluid. So, back to the question of Man’s special and sudden creation vs slow evolutionary changes: Unless God suddenly, specifically, and supernaturally designed and put into operation the extremely complex regulation of cardiac output, the first human who crawled out of the evolutionary slime, would have died within minutes, drowning in his or her own blood.

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