Your Heart, Your Medical
Heart disease continues to be one of the most prevalent diseases among adults in the United States. Although various forms of it are found in all populations around the world, the US has the dubious distinction of having one of the highest percentages of heart disease by total population. Considering the risk factors particularly associated with coronary artery disease - lifestyle stresses, tobacco smoking, diet, and lack of adequate exercise - many Americans find themselves in a high risk category for developing some form of heart disease during their lifetimes.
We live in a hectic, fast-moving society where stress is the norm. Although the number of tobacco users is decreasing, smoking continues to be a significant risk factor. And because we’re on the go so much, meal time is often fast food that translates to high fat/ high calories, so obesity is at epidemic proportions.
When we dilute those numbers down into the pilot population of about 600,000 certificated airmen, it’s not surprising to recognize that heart disease is one of the highest “pathology codes” that the FAA sees among pilots who apply for medical certification. From an epidemiological standpoint, that’s actually a good thing. Here’s why. The FAA as the regulator of medical safety in aviation establishes certification policy based on the perceived risk of incapacitation for a given disease or condition. The more data available, that is, the more people with treated disease that present to the FAA, the better the FAA is at assessing the incapacitation risk for the condition. Big numbers present better study data. The FAA has been granting special issuance authorizations to pilots with heart disease since the early 1980’s, so the medical certification process can in some ways be considered a huge prospective study that has spanned 3 decades, sort of like the famous Framingham heart study that went on for many years in Massachusetts.
There are more than 15,000 pilots flying on cardiac special issuances in any given year, so the odds of getting a medical certificate after having an MI, bypass, or stent placement(s) are actually very good, as long as the test data that you provide the FAA looks good.
The FAA uses the graded exercise treadmill stress test as the benchmark for cardiac medical certification. Exercise effort and duration are key physiological end points that are important for identifying risk. That’s why completion of the 9-minute Bruce protocol and attainment of maximum heart rate are so important. Maximum target heart rate is a simple calculation—220 minus your age equals your maximum heart rate, and that’s the number the FAA likes to see. That’s exercise tolerance, and exercise duration is the other key point. Nine minutes on the treadmill demonstrates that you have good exercise capacity, and the two components successfully accomplished reduce the likelihood of incapacitation from a cardiac event.
The other key component is the actual ECG tracing that indicates to your cardiologist how well your heart is functioning during that exercise stress. Part of the ECG tracing, the ST segment, indicates how well blood supply is being delivered to the heart muscle. The absence of blood supply is called “ischemia,” and that’s a disqualifying condition for medical certification. The presence of ischemia indicates there is untreated blockage in the coronary circulatory system. Untreated blockage means increased risk, and no medical certificate until the disease is treated.
We have detailed information on AOPA Online about many cardiac conditions and the process for gaining medical certification after an event. Fly safe and fly often!
July 14, 2011