Basic science review: the helix and the heart.
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See related editorials on pages 884 and 886. I t is an enormous privilege and honor to be asked to give the basic science lecture. Please join me on an adventure that I have taken over the past three years. I described this type of voyage to my daughters many years ago as “discovery,” in which you walk down certain common pathways but always see something different on that journey. I will tell you about my concept of how the helix and the heart affect nature, the heart, and the human. To pursue this new route, I select a comment from my hero, Albert Einstein, who said, “All our science, measured against reality, is primitive and childlike, and yet is the most precious thing we have.” We all have to be students, who are often wrong and always in doubt, while a professor is sometimes wrong and never in doubt. Please join me on my student pathway to see something I discovered recently and will now share with you. The object of our affection is the heart, which is, in reality, a helix that contains an apex. The cardiac helix form, in Figure 1, was described in the 1660s by Lower as having an apical vortex, in which the muscle fibers go from outside in, in a clockwise way, and from inside out, in a counterclockwise direction. This combination of clockwise and counterclockwise vortexes is common in nature. For example, within the flower bud of a daisy (Figure 2), there are clockwise and counterclockwise spirals. These flower buds increase in size as they proceed from the center outward. Insertion of a radial line across the spiral curve produces the natural pattern of enlargement, called growth (Figure 3). Nature contains many pathways of clockwise and counterclockwise spirals that are called reciprocal spirals. One example of natural reciprocal spirals is the sea shell. If one takes the tip of that shell and draws it outward, the formation becomes a helix (Figure 4), and that helix is very similar to the shape of the heart. These helical patterns are common in many animals with horns, such as the ram or eland, in which clockwise and counterclockwise spirals define their shape. If these horns counteract each other, from one animal in combat with another, they do not break, because nature introduces another trick—the formation of spirals within spirals; that is nature’s way of supporting one structure within itself (Figure 5). In a larger sense, nature introduces a harmony of structures from both outside and inside the visible shape. Looking into that harmony draws us back many years to the observations of Pythagoras in 600 BC, who described the golden section: the small is to the large as the large is to the whole (Figure 6). Throughout nature, there is a symphony of harmonies between different parts. The numerical character of this interaction was described by Fibonacci, living in Pisa in AD 1250. Mathematically, he defined this concept of harmony between parts as a logarithmic spiral, with a consistent relationship between proportions. Throughout nature, these logarithmic spirals are commonplace. A sequence we know best is the logarithmic spiral of DNA, a double helix holding the sugar and From the Department of Surgery, University of California at Los Angeles School of Medicine, Los Angeles, Calif.