Today I thought I’d address some thoughts about high blood pressure:
High blood pressure exists when BP is > (greater than) 140/90, though there are ranges of normal ranging from 100/60 to 130-135/80 depending upon which medical society articulates their ranges of normal.
It affects 1.5 billion people world-wide, about 1/3 of the world’s population.
(40 to 50 million Americans: 40% of African Americans vs. 25% of Caucasians and Hispanics) It accounts for about 54% of strokes and 47% of coronary events worldwide. Therefore, about half of cardiovascular events are specifically related to hypertension, and another large percentage related to pre-hypertension. Thus, high BP remains the leading cause of death worldwide and is one of the world’s great public health problems.
So exactly what is it? It is pressure in the arteries, initially observed with a vertical column of mercury to measure by millimeters the pressure generating in the artery of the arm!
Your arteries are tubes of muscle, just like your garden hose is a tube of plastic or rubber. When the water is pouring through the hose and gushes out the end, the hose is more flacid. When the nozzle is turned tight, and the water “jets” out, the hose is considerably stiffer. That is because of the tension in the walls of the hose generated by the flow of water and the volume of water passing through.
The arteries in your body are way more complicated. They are the muscle tubes that go through all areas of your body to deliver the volume of blood being pumped out of the left ventricle of the heart with every heart beat. For simplicity, figure the heart is beating 60 beats per minute, and it pumps out 100 cc’s of blood per beat. Therefore cardiac output would be 6000cc’s or 6 liters of blood per minute…and it can increase 5 or 6 fold with exercise, or intense activity by increases in heart rate and the increased amount of volume blood ejected with each heart beat.
Thus, into the muscle tubes pumps the blood, at high “spurting” velocity! Therefore, the upper number, Systolic BP (ie.120 to 140 range) is the tension in the wall of the artery when the 100 cc. amount of blood is moving through that measurement area, (thus the dynamic range), and …the Diastolic BP is the remaining, resting tension in the artery wall after the blood has passed by, (the passive range).
Now, I want you to start to think about all the many variables that come into play in setting these numbers of your blood pressure:
First is the number, the diameter, and the muscle thickness of all the arteries. The principle artery is the Aorta, and it may vary in caliber size from 20 to 25 mm (about an inch in diameter) up to over 40 plus mm. Every other artery branches off of the aorta (like other rivers coming off the Mississippi) and these arteries may have caliber sizes (diameters) ranging from 2 to 4 mm (like the coronary arteries) to 10 mm or more (like the carotids) to 15 plus mm like the iliac and femoral arteries.
In addition to the changing diameters of the arteries, there is also the substance of the 3 layers of muscle that make the arterial wall. How thick are these layers? How toned are the muscle layers? How pure are they in terms of muscle cell integrity, vs. are they infiltrated with problems of aging and atherosclerotic disease such as displaced muscle cells with inflammatory cells, cholesterol products, fibrin, disrupted collagen, calcium, clotting debris, etc.
Now think of the fluid going through the arteries, Blood, right? How thick or thin is it, how much volume is there? Is the body high in body water, and fluid volume, or is it depleted? Is the intravascular compartment (the circulation) dry, and dehydrated, or is there too much fluid, and salt, going through?
Then, what about the pump itself? How strong or weak is the heart? What is the size of heart, of the left ventricle? Does it contract normally and strongly, or is it weak and tired and impaired? Are the walls of heart normal, or are they thickened, making filling of the ventricles more difficult? Are the valves tightened down and lessening the flow of blood per heart beat, or are they leaking to the extent that there is back flow, interfering with forward flow?
These are just some of the mechanical issues which are complicated enough! What about everything else? What about you: your soul, your mind, your inner world, your struggles, your frustrations, your stresses? Yes, the cortex of your brain, which houses everything that makes you the unique soul that you are, plays a huge role in the dynamic settings of your body!
What about the pathways from your brain cortex to your inner brain centers that you DO NOT DIRECTLY CONTROL… but are the churning engines that make everything work in your body… like your pituitary gland, your hypothalamus and your pineal gland. These and other mid-brain areas are the control centers for your neuro-chemicals like serotonin, vasopressin, oxytocin, dopamine. These are the control centers for your autonomic nervous system- the Sympathetic system which releases, adrenalin, epihpehrine, nor-epinephrine, and its opposite, and the Parasympathetic system, which controls the Vagus nerve.
The pituitary gland (the Mother Ship) releases the control hormones like Growth Hormone, Anti-diuretic Hormone, Sexual Stimulating Hormone, Thyroid Stimulating Hormone, and others that control the release of all your end organ systems: thyroid, gonads, adrenals, etc.
In addition to this, is the flow of blood to your kidneys, as well as the kidneys ability to make urine. These as well as the adrenal glands are responsible for the release of chemicals called angiotensin, and renin coristol, aldosterone , that play a direct role in the maintenance of correct body water, as well as a direct impact on the measured “tone” in your arterial system.
I could go on. This type of essay could go on for many pages, and be expanded into chapters in medical text books. My intent here is only to give a very basic appreciation of how complicated biological science is, and how amazing our human bodies are.
There is also an effort to help you understand that there is so much that can go wrong, and it’s amazing that more doesn’t! These are areas of molecular biology, of physiology, of genetics, as well as behavior that are intersected in the most complex ways. It is the unfolding of these many variables that over the decades of our lives, with the interplay of our behavior, our diets, our tensions, our stresses, and our level of activity or inactivity, that can lead us to the place where overt disease expression occurs: Coronary Heart Disease, Heart Attack, Congestive Heart Failure, Arrhythmias, Sudden Death, Stroke!
Because the science of hypertension is so complex, there are many different types of medications that are called upon to treat it. About 8 classes of medications: mostly with about 5 to 10 different drugs in each class, and each drug usually has multiple doses to choose from. So, for any individual, it becomes somewhat of a creative recipe. Best to start with one drug at a time, keep the dose low, and work up if needed, and do one thing at a time. Each person is their own unique environment. Two things need to occur: 1) the drug needs to work to achieve goal, and 2) you have to feel well on it. Stay away from side effects!
In fact, the importance of reduction of BP is critical for every decade, even into the 30’s. The difference in each decade, is a 2 to 4 time lowering of cardiovascular events when correctly treated. These outcome differences are based on studies done over many decades, involving hundreds of thousands of people cumulatively, so these statistics bear great scientific weight.
I’m hoping to surprise you now!
I’m not going to discuss blood pressure medicines! The foundation of management of BP, and CardioVascular risk reduction in general is to work with the patient with life style modification: So folks, if you want to work on these risk factors “naturally”, then go at it!
Lifestyle modifications are recommended for just about everybody with high blood pressure:
- Work on your weight.
- Work on your body.
- Work on your soul and your mind.
- Lower your BP, Lower your Cholesterol, Lower your Blood Sugar.
- Lower your stress, get better sleep, do more activity, enjoy your family, find and nurture love.
There is so much more to this!
There will be a medication essay, as well as a cholesterol medication essay….BUT:
My next essay to you will be called: “The Not So Easy Tidbits To Living a
Attached is a nice video to help you understand the dynamics of blood pressure.
Brian Chesnie, MD.