The Harmony of Hemodynamics
There is an incredible amount of harmony in the body, and it begins with hemodynamics, the way in which our blood circulates throughout the body. The ebb and flow, the almost tidal rhythms, the force of the heart, all flush the body with blood and cleanse the very essence of our being. Keeping it all in balance... that is the goal of our lives, and it is nowhere more evident than in our blood. Without the balance and harmony of hemodynamics, our blood would pool and stagnate in our feet and leave our minds dry and lifeless. The very essence of this system is our heart. Researchers around the world are finding evidence that the heart is more than a simple pump. In fact, there may very well be a two-way feedback loop between the heart and the brain. The heart seems to have its own link to the brain and nervous system, and even seems to help with maintaining the balance between our brain’s left and right hemispheres. Most importantly, there is a substantial amount of evidence that the heart and its electromagnetic field are sources of intuition, intimacy, and creativity.
So just imagine that this amazing pump is actually a source of intuition and creativity. That may mean that these traditionally mental aspects may dictate how our blood is pumped and to what areas of the body. This is because the heart has extensions of its very tissue (and corresponding nerves) throughout the entire body in the form of our circulatory system. So just as the heart is living tissue with the potential for insight and emotion, so does the circulatory system. This may explain why our circulation can shift so dramatically with stress. It may not just be result of hormonal biochemical signals, but also our emotions themselves.
The heart is located mostly to the left of midline above the diaphragm. It has four chambers: two atria above and two ventricles below. It is surrounded by a triple layered sac of tough connective tissue and a fluid membrane known as the pericardium. The wall of the heart is made of three layers of muscle and connective tissue that extends out beyond the heart to form the blood vessels of our body. The four chambers of the heart are structured according to their function. The two atria have thin walls, which contract at the same time and have only to push blood into the ventricles below. The ventricles, however, must move blood significantly further, and so must work harder. Although they contract at the same time to expel blood, the right has only to move blood to the lungs, while the left must push blood all the way to the toes. So the left ventricle has a muscular wall that is two to four times as thick as its partner on the right.
To prevent backflow of blood, the heart has valves that open and close in response to pressure changes as the heart contracts and relaxes. Valves also guard the arteries exiting the heart so backflow does not occur, especially because blood moves from an area of higher pressure to that of lower pressure. So if the pressure in the aorta exiting the heart is greater than the pressure inside the ventricle of the heart, the blood will tend to backflush through the semilunar valve into the heart, creating a murmur. Murmurs can also be caused by a weak valve that can be genetic or can have developed as the result of an infection.
The pace of the heart is controlled by autorhythmic fibers in a specialized area just below where the blood enters the heart. This area is known as the sinoatrial node or SA node. The SA node sends the mineral sodium throughout the muscle fibers of the heart causing a release of calcium ions and the contraction of the muscle fibers, thus setting the pace for the heart. The SA node can be affected by the autonomic nervous system, drugs, electrolyte imbalances, hypoxia and stimulants such as caffeine. It also is temperature sensitive. There are even herbs that can affect the heartrate such as Motherwort, Corydalis, Cramp Bark and Hawthorn.
The control of the SA node and the rate of the heart come from the medulla oblongata in the brain, part of the autonomic nervous system. Heart rate is increased by the hormone epinephrine, while heart rate is decreased by acetylcholine (choline being a biochemical synthesized in the liver). In a normal cardiac cycle, the two atria contract while the two ventricles relax. Then, while the two ventricles contract, the two atria relax. This heartbeat will occur at the rate of 75 beats per minute in the average resting adult.
The main blood flow that surges through the body ifrom the heart s called systemic circulation and is pumped by the left side of the heart. The right side of the heart pumps a closed route directly to the lungs known as pulmonary circulation. Problems with the right side of the heart will cause varicosities to occur in the legs and even the arms. Additionally, the heart maintains its own circulatory system, known as coronary or cardiac circulation, delivering blood to the tissue of the heart when the heart is between contractions. This specialized circulatory pathway reminds us that the heart and its attachments are again, living, breathing tissues. Cayenne is one herb that has traditionally been used to improve this myocardial blood supply.
Through the heart and these living tubes of tissue our body not only provides the pathways for the movement of blood, but also influences and controls this movement to better accomodate the body’s ever-changing needs. Arteries carry blood away from the heart and veins carry blood from tissues back to the heart. The walls of the arteries have a similar structure to the wall of the heart, so they are quite muscular which allows the arteries to relax or contract to push blood along or to restrict its movement. They are the main control mechanism for blood flow to every cell of the body. The larger arteries are very elastic to allow the surge of blood from the heart to flow quickly and easily to the body. Medium-sized arteries are more muscular and distribute blood to body areas by adjusting the speed of the moving blood. They can also direct blood to one area instead of another.
The alternate expansion and contraction of these elastic arteries create a traveling pressure wave that is called the pulse. The pulse is strongest in the arteries closest to the heart. The radial artery at the wrist or the carotid artery in the neck, are the most common places to feel the pulse which is normally the same as the heart rate. These larger arteries lead to smaller and smaller pathways delivering blood to the capillaries, which control blood flow to individual groups of cells. For instance, Raynaud’s Syndrome is a spontaneous spasming of the smaller arterioles shutting off blood flow to the fingers or toes.
Capillaries are the smallest vessels with semi-permeable walls that permit blood to seep out into the areas between cells. The higher the metabolic rate of a tissue, the more capillaries it will have. This process of "growing" additional capillaries is called angiogenesis, and is common not just in natural tissue, but in cancerous tumor growth as well. Capillaries do not have any muscle and respond to pressure changes. Again, blood flows to areas of less pressure, so if there is higher pressure in the capillaries, blood will flow out into the interstitial spaces. Once the pressure in the interstitial spaces rises, it begins to flow into the capillaries drawing fluid from the cells and the extracellular spaces with it to be returned to the heart. Often, the capillaries can be weak, or high blood pressure can force blood through the capillary walls improperly. This causes spider veins, broken capillaries in the face and blood moles. Increasing Vitamin K or rutin plus the wonderful herb Horsechestnut can really help to prevent this by strengthening the capillary walls and preventing bruising.
It is from the capillaries that blood exchanges nutrients, oxygen and other substances with the cells. Wastes and substances being secreted by tissue cells move in the opposite direction. The amount of exchange depends, again, on water pressure in the blood versus the water pressure in the extracellular fluid. These blood capillaries can also form wider structures known as sinusoids, and are found in many areas of the body such as the brain, the liver and the spleen.
Capillaries unite after leaving a tissue area, forming a venule or small vein which carries the blood to the larger veins. Most veins have at least two and some have three layers to their walls, but the amount of muscle tissue is substantially less in the veins. The average blood pressure in veins is much lower because they do not have the pressure of the heart pump behind the blood flow. Instead, the veins have valves to aid the flow of blood. They prevent backflow of blood and continue its motion towards the heart, almost like locks in a canal. When they weaken, you develop varicosities which is a porousness of the walls of the veins. Chronic long-term standing, weight gain or downward pressure on the legs can increase varicose vein development.
Two additional mechanisms that help with the blood’s return to the heart are the contraction of the muscles in the legs and the pressure changes in the chest and abdomen during breathing. As mentioned previously, in the veins blood moves from an area of higher pressure to an area of lower pressure, through a valve, forcing the valve to close behind it. At any given time, most of our blood is in the veins, because they have the ability to expand and to hold large reservoirs of blood. In this way when blood is needed quickly, it can be drawn from the veins, such as during exercise or in the case of injury. Many reports and studies have indicated that because of this, the venous return of blood is the most important factor in regulating blood flow from the heart. And the most important treatment to enhance this factor is Massage Therapy which works directly on venous blood flow.
Blood pressure is the pressure exerted by blood on the walls of a blood vessel. It is highest in the aorta and is generated by contraction of the ventricles of the heart. It is generally about 120 during contraction [the upper number which is systolic] and drops to about 80 during relaxation [the lower number which is diastolic]. Blood pressure is usually measured in the left brachial artery using a sphygmomanometer. Pressure rises with increased blood volume and increased resistance caused primarily by the friction between the blood and the walls of blood vessels.
This means that the longer a blood vessel is, the greater the resistance will be as blood flows through it. Many obese people have hypertension, simply because of the added length of blood vessels, generally about 200 miles of additional blood vessels for each extra pound of fat. Also the smaller the width of the blood vessel, the greater the resistance. So if there is a restriction making a vessel smaller, such as muscle tension, scar tissue or internal plaque, then blood pressure will be higher. Another factor in blood pressure is the thickness of the blood or blood viscosity. Blood tends to thicken if it has a higher number of red blood cells to the water content of the plasma. Only recently has there been suggestions that alcohol consumption may be another important factor.
But don’t get the idea that blood pressure is dependent only on the condition of the vessels. In fact it is controlled primarily by the medulla oblongata of the brain. This area controls the heart rate, the contraction of the blood vessels and their diameter. The brain receives information from receptors such as baroreceptors in the aortic arch, about blood requirements throughout the body. It then reacts to this information to continually adjust blood flow and blood pressure by releasing hormones that can regulate blood pressure such as epinephrine, norepinephrine and ADH [vasopressin]. In fact many of the hormones regulating blood pressure are interrelated with adrenal function. The adrenals are notorious for reacting to stress and emotion, making highly stressful periods also the most common for an increase in blood pressure.
When blood pressure has been high for a period of time, it can cause the nervous system to progressively reset acceptable blood pressure limits at higher and higher levels. This delays the body’s natural reactions to reduce blood pressure from taking effect. This sustained higher pressure causes smaller blood vessel walls to thicken, making resistance higher. This condition known as hypertension can cause headaches, strokes and inflammatory conditions such as phlebitis.
The first thing to address is adrenal health and lifestyle factors that affect the hemodynamics of the body. Low blood pressure is common among adrenal fatigue cases, obese individuals and vegetarians. There are a number of reasons for low blood pressure, but the most common are Vitamin B and C factors, essential fatty acid levels and nerve conductivity of the heart. Cleansing the liver and the kidneys can reduce resistance to blood filtration and circulation.
There are herbs that have a pronounced effect on reducing blood pressure such as garlic. For centuries allium sativum has been confirmed to have anti-hypertensive effects and to favourably influence other cardiovascular risk factors, such as high cholesterol. Coleus can reduce the thickness of the blood with its excellent antiplatelet activity. Dandelion Leaves have a mild diuretic effect and are particularly good for elevated systolic pressure in the elderly. Cramp Bark is essential for reducing muscular tension which can be a driving force behind high blood pressure. And don’t forget phosphorus, particularly ortho-phosphoric acid which is also great for reducing the thickness of the blood and taking the pressure off of the heart.
But the more common scenario is that blood pressure fluctuates throughout the day and also as a reaction to lifestyle and nutritional challenges. For this reason hypertensive medication can create significant side-effects, because rarely is the body in a constant state of high blood pressure. I have had patients actually pass out on the sidewalk because their blood pressure had dropped to a dangerously low level with their hypertensive medication.
Mistletoe is a wonderful herb for fluctuating blood pressure as well as Standard Process Circuplex. Fluctuating blood pressure requires a special combination that can address both the circulatory and nervous systems to modulate blood viscosity, balance blood circulation and free amino acids from the blood to tissues. I have found that any patient that complains of burning or prickling sensations in their extremities or cold hands and feet can use some circulatory support.
Another aspect of balanced hemodynamics is the health of the structure of blood vessels. There are many instances where damage can be sustained by blood vessels and without proper repair, blood circulation can be compromised. Bilberry is the perfect herb for repairing and restoring microcirculation, particularly in the brain, eyes and glandular tissue. If vision has suddenly weakened, then Bilberry will be thing to pull off the shelf. Vitamin K food complexes will restore strength and elasticity to capillary walls, particularly if there has been any damage by viruses or bacteria creating elevated C-Reactive protein levels in the blood. Finally Wheat Germ Oil is such an amazing vitamin E complex that the levels of antioxidants present seem to target scar tissue and damaged connective tissue to speed the healing process even after years of damage.
A rather new idea regarding our hemodynaics is the idea of homocysteine. Homocysteine is a normal waste product of protein digestion, but high levels of it can produce plaque which is a mixture of fat and calcified inflammatory tissue. Areas of blood vessels can then be lined with this plaque which will then weaken the vascular walls, making them more prone to damage from high blood pressure or injury. This plaque will create a narrowing of the opening of the vessel making it more difficult for blood to flow smoothly. So if you are eating a high-protein diet, be sure to increase your intake of vitamins B6, B12 and folic acid, as these will all keep your homocysteine levels in line.
But the most talked about issue regarding our circulation is cholesterol. There is so much to say about cholesterol that it is almost overwhelming to even mention it. So much of what is told to us by our doctor is incorrect and the most recent research has even pointed out that a high fat diet does not lead to an increased risk of heart attack or stroke, as originally believed. There is so much we don’t know about the body, but what we do know is that almost every function that we have involves the use of essential fatty acids. Reducing our intake of fat to lower cholesterol does nothing but harm for the body. Adrenal steroidal hormones, the myelin sheath of central nerves, energy reserves, joint support and lubrication are just a few of the myriad of body structures and functions for which fat is essential.
But if your blood cholesterol level is too high and the Lipitor fairy is hovering over you, what can you do? Well, the first thing is to enhance the efficiency of your fat digestion by supporting your gallbladder with choline and cleansing the liver. Fatty deposits in the liver can inhibit proper liver function as well as prevent effective blood filtration. Some of the best formulas for high cholesterol are Soy Bean Lecithin (except in cases of osteopenia or osteoporosis), Garlic, Globe Artichoke and Standard Process Cholaplex. Also increasing the healthy essential fats such as GLA and DHA can help to reduce blood cholesterol levels. My favorites are Black Currant Seed, Borage, cold-water fish oil and coconut oil. These are especially indicated if there are any skin disorders such as eczema, psoriasis or excessive dryness.
Balancing the blood can not only address some of our most prevelant issues such as high cholesterol and high blood pressure, but it can restore so many of our vital functions that we can regain the bodies of our youth, literally!
Karen Clickner, N.D. is the founder and director of ISIS Holistic Clinic & The Waters of ISIS Body Purification Spa in Brookline, MA.