Residual Functional Capacity Assessment for Aortic Aneurysms
What Is RFC?
When the threat posed by your aortic aneurysm is not severe enough to meet or equal a listing at Step 3 of the Sequential Evaluation Process, the Social Security Administration will need to determine your residual functional capacity (RFC) to decide whether you are disabled at Step 4 and Step 5 of the Sequential Evaluation Process. RFC is a claimant’s ability to perform work-related activities. In other words, it is what you can still do despite your limitations. An RFC for physical impairments is expressed in terms of whether the Social Security Administration believes you can do heavy, medium, light, or sedentary work in spite of your impairments. The lower your RFC, the less the Social Security Administration believes you can do.
Assessing Impairment Caused by Aortic Aneurysms
The problem with survival numbers in the medical literature regarding aortic aneurysms is that there is no correlation of data with the exertional levels of the patients. For example, the fact that a person with an uncomplicated dissecting abdominal aortic aneurysm could survive as long with medical treatment as someone with surgery does not imply that they would have the same exertional capacity. Actually, the exertional capacity probably would not differ in asymptomatic aneurysms; the real question is what level of exertion is likely to provoke rupture and almost certain death. No one knows what the risk is for various groups of patients with various types, sizes, and locations of aortic aneurysms undergoing various types of exertion. No one is ever going to do such a study. Certainly, there is SSA precedence for limitations to prevent death, such as exertional limitations to prevent precipitation of arrhythmias or ischemia, or environmental restrictions to protect claimants with epilepsy.
There is no question that exertion incrementally increases blood pressure, including pressure throughout the inside of the aorta. With heavier types of lifting, there is tensing of the abdominal muscles, a Valsalva maneuver, that compresses the aorta and results in an increase in intra-aortic pressure. It only makes sense that this would increase the risk of rupture. There is also anecdotal evidence that abdominal straining, even without lifting, has been associated with fatal rupture of aneurysms. If there is a dissecting aneurysm of any kind, no higher than a sedentary RFC should be given. Certainly, long dissections should receive no more than a sedentary RFC, even if the dissection is medically stabilized. However, especially in Type I dissections, serious consideration should be given to whether your impairment meets or equals the listing. The SSA will generally accept a restriction to light work for any un-operated thoracic aneurysm, even if it is not dissecting.
Many of the aneurysms seen in disability claimants are non-dissecting, discrete, and slowly growing abdominal aortic aneurysms. It is difficult to say what these individuals can safely perform in regard to physical exertion, even though most are asymptomatic. Small aneurysms that are nearly normal in size, such as 4.1-4.4 cm, could receive a “not severe” rating. Aneurysms 4.5-5.0 cm could conceivably do medium work. Abdominal aortic aneurysms of 5.1-5.5 cm should receive no more than a light work RFC, and those that are at least 5.5 cm should have surgery as a result of rupture risk. Very large, un-operated aneurysms, such as those 6.0 cm and more, could easily justify a sedentary RFC. There is nothing scientific or rigidly constraining about these numbers, or reflective of any SSA policy; they are only guidelines, but much better than no conceptual framework from which to proceed in analyzing individual cases. Based on one study, it could be argued that small aneurysms should be a basis for restricting heavy exertion. See Emotion, Exertion and Aortic Dissection.
Vocational experts are aware of how restrictions on bending can greatly limit the available occupational base for heavy and medium work jobs. Particularly in older, less-educated claimants with long histories of some type of heavy or even medium work, a limitation on bending to no more than occasional on an RFC can control the final medical-vocational disability determination in regard to allowance or denial. When it comes to the possible transferability of work in such claimants, substantial limitation in bending can effectively reduce an RFC to light work even if lifting limitations represent more than light work. It is known that intra-abdominal pressure increases with bending, and would be further elevated if bending and lifting. Such an increase in intra-abdominal pressure could affect intra-aortic pressures and have an adverse effect on the aneurysm, i.e., increase the probability of rupture at some point in time. There is no proof that rupture risk increases with bending and lifting, and there probably never will be such evidence other than on an anecdotal basis, such as the patient who ruptures his aortic aneurysm and dies while straining to use the toilet. That is known to happen, and the same kind of straining happens with lifting; it is called a Valsalva maneuver. SSA adjudicators rarely or never think of restricting bending for abdominal aortic aneurysms, but that does not mean the limitation should not be given.
Another RFC issue is the safe exercise capacity of claimants who have had their aortic aneurysms repaired. When there are discrete aneurysms that have been completely repaired with a graft, the claimant will have no exertional limitations, provided that surgery has not been required for aortic arterial branches to vital organs, such as the coronary, mesenteric, or renal arteries. For example, a claimant underwent emergency surgery for a Type I dissecting ruptured aorta, and had the entire aorta grafted including attachment at the aortic valve of the heart. In fact the aortic valve had to be replaced and the coronary arteries surgically re-implanted through the graft. He was allowed on a medical-vocational basis with a sedentary RFC. In simple, uncomplicated repairs of discrete abdominal aneurysms, there would be no reason to limit bending or give any other RFC restriction.
However, while complete open surgical repair of discrete abdominal aneurysms with graft replacement can result in no limitations after healing, such assumptions are not warranted in the case of the new endovascular surgical techniques that are less invasive and done with a catheter through femoral artery entry rather than an open abdominal approach to the aorta. There is no current evidence that endovascular procedures reduce rupture risk. In fact, endovascular leaks occur in about 10-20% of cases. Also, follow-up imaging over time cannot be done with MRI when metal stents are used. Until endovascular procedures improve and ongoing studies clarify risk profiles for the various sub-groups of patients, SSA adjudicators should not assume that claimants who are post-endovascular surgery have no limitations even if the treating physician states there are no limitations. Certainly, such a position cannot be supported based on current medical knowledge.
There is no need for the SSA to accept guesses at aneurysm size. Thoracic and abdominal aortic aneurysms would have been measured by the treating physicians during angiography, or CT scanning, or MRI scanning, and those records should be available. As previously mentioned, abdominal aneurysms can also easily and safely be measured with abdominal aortic ultrasound that the SSA can purchase.
Emotion, Exertion and Aortic Dissection
In one study, 40% of patients identified emotional distress as the precipitating factor preceding the onset of dissection pain. In the same group of patients, 27% said that strenuous exertion preceded the onset of pain indicating dissection. If both strenuous exertion and emotional distress were present, the percentage increased to 67%.
Some examples of strenuous exertion described by patients were “shoveling snow,” “lifting weights,” “changing storm windows,” “lifting a granite commode,” “swimming,” “playing racquet ball,” “doing push-ups,” “lifting heavy machinery,” and “very vigorous sex.” Emotional distress examples given were “very upsetting news,” “bad business lunch,” “just given diagnosis of lung cancer,” “big losses at the casino,” and “extremely stressful business trip.”
Aortic dissection incited by emotion or exertion was not dependent on age, gender, aneurysm size, or aneurysm location in the ascending or descending aorta. Some aneurysms were as small as 3.1 cm.
It is theorized that transient increase in blood pressure during physical exertion or intense emotions stresses the weakened aneurysmal aortic wall and allows the onset of dissection of blood into that vessel’s wall. There is no way to prove this theory, but it is most likely correct.
Go back to About Aortic Aneurysms and Disability.