We have discussed stroke and transient ischemic attack (TIA) before, but we haven’t covered the pathology that contributes to stroke risk in our population. The carotid arteries are major vessels that deliver blood to the brain, so they are important conduits to keep open to maintain the free flow of oxygen and nutrient-rich blood to our cranium-encapsulated super-computers.
One of the most common causes for cerebral vascular accidents (CVAs) is the deposition of fatty substances called plaques that build up slowly over time in our arterial blood supply. It’s the same process that happens in coronary arteries that leads to heart attacks.
Interventional cardiologists treat coronary blockages with stents. In advanced cases of carotid artery disease, the surgeon might perform a carotid endarterectomy to clean out the accumulated plaque buildup. If you’re handy around the house and have had to unclog a kitchen sink drain, the gunk that causes sluggish draining is like what a surgeon might find in those cases where an endarterectomy is indicated. Different makeup of the “gunk,” but you probably get the picture.
Because this process is slow and insidious, the patient might be unaware of any subtle symptoms until those symptoms manifest in a TIA or full-blown stroke. Screening for carotid artery disease, as you have heard before from our Wellness Consultant, Dr. Jonathan Sackier, is often a useful tool in heading off significant disease before serious problems develop. A carotid Doppler ultrasound is commonly used to evaluate the anatomy of the carotid arteries both in screening for disease and for follow-up after diagnosis and treatment.
From the aeromedical certification perspective, the FAA looks favorably on effective treatment for carotid artery disease if the diagnosis is made early. In fact, a high percentage of blockage in the coronary arteries is allowed for medical certification if the person is asymptomatic and is being appropriately treated and followed.
Unlike coronary artery disease where a higher percentage of blockage elevates the risk for incapacitation, the carotid artery circulation involves the common carotid artery that divides into the external and internal carotids. This redundancy allows for less risk of an incapacitating event, so the FAA is somewhat more lenient when they evaluate carotid artery disease that involves more than 50-60% blockage.
If there is no stroke in the history, but carotid artery disease is in the history, the FAA will require a cardiovascular evaluation, including a treadmill stress test to rule out any heart disease that often is present with carotid artery disease. A good narrative summary report from the treating physician should include the history of symptoms, the treatment performed, medications prescribed, current lab work including cholesterol, triglycerides, and fasting glucose, and a recent (in the last 90 days) carotid ultrasound are usually required for the initial review.
The pilot will be granted a special issuance authorization and will require annual follow up for continued medical certification. That follow-up usually includes an updated status report and carotid ultrasound.
As we are all part of the aging pilot population, prevention is the best investment to avoid serious consequences. Dietary changes, medications, such as statins to lower blood lipids, cholesterol and triglycerides, good control of blood pressure, not smoking, and regular exercise are some of the ways to hedge our risks for serious diseases as we age.
Thanks for reading. Fly often and fly safely!