Peripheral Artery Disease

 

 

Peripheral Vascular Disease - By Dr. Samuel E. Sanchez, DO

www.MedicalHealthEducationBlog.com & www.DrSamuelESanchez.com

Welcome back friends, it is time again for Medical Health Education Blog.

Brought to you by our friends at: Sanchez Family Entertainment, Inc.

In our last blog we discussed and defined the following terms: If you need review on these terms, please reevaluate our last lecture known as Essential Hypertension.

1. Essential Hypertension     4. Vascular Tone

2. Blood Pressure                 5. Vascular Compliance

A. Arterial                             6. Endogenous

B. Venous                             7. Exogenous

3. Vascular Resistance

Imagine that you playing with your grandchildren. Suddenly your legs feel as if they weigh a thousand pounds. So you take a break, sit down, and relax, and the throbbing that you were feeling quickly dissipates. As you rub down your lower legs and feet, you notice that they are strangely cold, and the color of the skin appears to have changed to a reddish purple mixture. You then sit back, raise your legs, and wait. Within about 10 minutes you notice that everything returns to normal.

The next day, you call your personal physician and describe the events that occurred. He reassures you that you are fine, but schedules you to come in the following day, and instructs you to go to the local radiology center as soon as possible, or to the local emergency room for an ultrasound of your veins. You decide that it is more cost efficient, and time savings to visit the local imaging center, so you make your way there.

Once at the imaging center, you undergo an ultrasound, known as a venous Doppler. Upon conclusion of the venous Doppler, the ultrasound technician also reassures you, loads up the results on the computer, and sends them to the on call Radiologist. After having the Doppler read, your are released and sent home. By now you are feeling pretty good. “A clean bill of health,” you think to yourself, “I only hope the center’s bill will be as clean.”

Since you are feeling elated, you call and cancel tomorrow’s doctor appointment. Every thing seems to be going well, until, the following week. You are playing a pick up basket ball game with some friend, something you haven’t done in over a year. I mean you just got a clean check, and you’ve felt like your at the top of your game. Suddenly, you get the ball on a break away, your headed to the hoop, your about to release your famous jump shot when suddenly, you collapse.

Your are taken to the local emergency room by ambulance and paramedics. In route, you notice that this time your legs are purple, cold, swollen at the ankle, and very weak. The paramedic asks you a list of questions, and you inform him that this happened a couple of weeks ago, but that the Ultrasound was fine. He then asked you what did your doctor say when you followed up with him, and you informed the paramedic that you had not seen your doctor in over three years, but that you did talk to him on the phone to set up the appointment. The paramedic then asked you if you had, or were experiencing the following symptoms, chest pain or heaviness, shortness of breath with exertion, palpitations, headaches, dizziness, fatigue, heaviness of the legs, skin color changes, heat or cold intolerance, wheezing, cough, sputum production, fever or chills. Your replied that prior to a few weeks ago, you had never experienced any of these, but since then you have felt, a mild shortness of breath with exertion, swelling of feet, cold feet, heaviness, and skin color changes. Upon arrival to the emergency room, your paramedic relays the significant information to the on call emergency room physician.

After you have been stabbed and prodded by the nursing staff, in what seems like an eternity, the physician enters into your room. He reviews the history with you and obtains your family history. You explain that your Father has had two heart attacks, and has under gone a Coronary Artery By Pass Graft surgery involving three vessels. Prior to his surgery, he had two stents placed, and developed lung disease due to years of smoking. The doctor then asks you when was your last cardiac exam, and you reply never. He then inquired of you if you have ever suffered from lung disease, diabetes, cholesterol or hypertension. You inform him that you have “healthy as a horse”.

The doctor leaves the room, orders a battery of tests, including a chest CT scan, EKG, repeat venous ultrasounds, labs, and a Chest X-Ray. After completing all the tests, a feeling of uneasiness starts to grow in the pit of your stomach, “what is all this gonna cost?” you thought to yourself. Just then the Doctor walks in, smiling, “I have some good news sir, there was no heart attack, lung problems, or blood clots. I only want to order one more test to see why your legs are so weird.” You agree to the test, and in walks the very same ultrasound technician you met two weeks ago. Now your feeling better. He takes you to the room, pulls out the probe, lubricates your legs and begins the test, within 2 minutes he excuses himself and runs to get the doctor. The doctor reviews the findings, and the smile leaves his face. We need to get you into surgery stat.” he replies. “Your blood supply to your legs are extremely compromised, and if left alone, you will lose both you legs.”

Rationalization is one of the most common reasons that people fail to follow their treatment plan, or failure to seek out the necessary medical assistance that they require. We can only estimate the countless times that our family members have been lost due to this emotional killer. Rationalization is the one of the brains defense mechanisms. The brain deploys its uses when it is too afraid to deal with what it perceives may be the problem. Rationalization leads to rejection of care, inadequate care, procrastination of care, or just engaging in self care, when more is needed. This low level of care often leads the patient to irreparable harm, and death. Rationalization is recognized, mental health disease, and left untreated can result in the progression to phobias, panic disorder and psychosis when the ability to rationalize is breached. Rationalization either limits or destroys compliance to care.

Here we find that this patient experienced Peripheral Vascular Disease. We define PAD as a blood circulation disorder of the vessels (artery or vein), outside the heart or brain, due to 1. narrowing, 2. blockage, or 3. spam. Initial signs (symptoms) for PAD are fatigue and pain of the lower extremities, particularly during exercise.

During our last lecture, we reviewed the following vocabulary phrases, Vascular Resistance, Vascular Compliance, Vascular Tone and Essential Hypertension. We compared how these conditions either lead to, or detracted from, the development of Essential Hypertension. Let us take a moment to review the meaning of these vocabulary words so that we can apply them to the concept of Peripheral Vascular Disease.

If you remember, Vascular Resistance is the force that the blood flow must overcome, in order to allow the movement of blood. Think of this resistance as pushing against the tide, and that the tide must be stronger that the resisting force, otherwise the tide fails to move. On the other hand, Vascular Compliance – is the ability of the vessel’s muscular walls to expand or enlarge passively (no energy) to accommodate for changes (increasing) blood pressure. Here we find that the tide has a very strong unidirectional force, this force places an equal force on the walls of the river’s banks. In this case, the banks comply spontaneously with the force, and expand to accommodate it. This expansion has a direct affect on the force or pressure, causing it to drop. Finally we review the notion of Vascular Tone. Vascular Tone is the force exerted by the muscles in the walls of the vessel, down upon the movement or force of the blood flow. In the Panama Canal, there are movable walls. As the flow of water moves the ship from east to west, the closing walls exert a force on the flow of water from north to south,

slowing the movement of the ship. Therefore, the normal pressure of water, flowing from east to west, is affected by the force induced upon it by the north to south closing of the walls. In other words, as the walls the close, the normal pressure is increased. Hypertension is a condition when the force exerted upon the vessels walls are higher than it normally should be. As we can see, when the canal’s walls exert pressure upon the east west flow of water, the east west flow of water exerts an equal force upon the canal’s walls. This secondary force or pressure on the canal, by the water, is higher than it was before, and therefore a larger force than normal, because now it has to exert its force from east to west, and from south to north as well.

So now we have a clearer understanding of Resistance, Compliance, Tone and Hypertension, but how does that relate to biological changes that can lead to Peripheral Vascular Disease, and what leads to these changes? Remember, Vascular resistance is the pressure (east to west) that the blood must overcome, in order for the blood to able to move. If the pressure in front of the blood flow is greater than the blood flow, the flow will reverse course, or be displace backwards. If the pressure is equal to the blood flow, then there will be no net loss or gain in movement, but rather a stagnant flow. Vascular Tone - is the force exerted by the muscles in the walls of the vessel, down upon the movement or force of the blood flow. Again, if the north to south force exerted upon the east to west blood flow, cause the blood flow in front of the ship to be greater than the east west flow, then the ship’s movement reverses, from west to east. Since Vasospasm – is a condition in which the vessel’s muscles (canal’s walls) close, causing the vessel’s diameter to shorten. This causes the same (north to south) increase in pressure we previously saw by the canal’s closing. This increased pressure witnessed by the spasmed vessel, exerts a force upon the blood pressure, therefore increasing it, or Hypertension, Vincent's Angina. Vasospam can be affected by anything that causes the vasculature muscles to tighten, such as, but not limited to hormones, epinephrine, nor-epinephrine, sympathominetics, caffeine, amphetamines, and stimulants. The same substrates can have a similar affect on vascular resistance.

By now we should understand the cause effect relationships between blood pressure, vascular compliance, vascular tone and vascular resistance. In a sense, vascular compliance is antagonistic of vascular tone. Both are caused by effects upon the vessels muscles. One, compliance, causes an increase in the diameter of the vessel by relaxing the muscles. The other, vascular tone, cause a decrease in vessel size by casing the muscle to contract. The first, compliance cause a decrease in blood pressure, and the second, tone, causes an increase in blood pressure.

The last effect upon the vascular walls that we are going to discuss in this article is exogenous effects on the vessel, Vascular Hardening. In order for the initiation of vascular hardening to occur, there has to have been previous damage to the walls of the vessels. The most common cause of wall damage is the force exerted on the walls by Hypertension, but other things that cause damage to the wall can also start this process. Consider collagen vascular diseases, such as Lupus, Rheumatoid, Sjorgens, Psoriasis, and many others. Also consider the effects of infections origin, such as Rheumatic Heart Disease, Syphilis, or other spirochetes. This vascular destruction cannot be left alone, it must be repaired, and when it is, that is when all the fun begins. The inflammatory cells, repair cells, and others, all secrete substances that not only affect healing, but also affect pressure. Additionally, the different forms of cholesterol floating in the blood stream can become attached to the surface where the healing is taking place, dissolve into that area, and begin the formation of plaques. Claudication is impairment of walking, pain, numbness, fatigue and discomfort of the legs, caused by exercise, but due to poor circulation of the extremities. Claudication is relieved by rest, and opening of the vessel. Usually the claudication is secondary to severe vasospams, as seen with certain medication, or cholesterol plaques that retard vascular compliance, while increasing tone and resistance.

So far we have added to our vocabulary. We have increased our understanding of the pathophysiology of blood vessels. Next we are going to take this acquired knowledge, and apply it to the heart. Our next lecture will be on Coronary Artery Disease.

Vocabulary Words:

1. Essential Hypertension 4. Vascular Tone              9. Vascular Hardening

2. Blood Pressure              5. Vascular Compliance 10. Vaso Constriction

A. Arterial                         6. Endogenous                11. Claudication

B. Venous                          7. Exogenous                 12. Peripheral Vascular Disease

3. Vascular Resistance       8. Vaso spasm                13. Rationalization

By:  Samuel E. Sanchez, DO

God Bless.