Exercise Management Aneurysms Chapter 16

Exercise Management Pathophysiology Aneurysms can be caused by congenital or acquired diseases, are usually asymptomatic, and are often not discovered until they rupture or cause symptoms due to localized pressure on an adjacent tissue. Most aneurysms occur as a function of aging and are progressive in nature with the tearing of the arterial wall (dissection), and sudden rupture of the artery

Exercise Management   The aorta is the next most common artery site of aneurysms, typically at the abdominal aorta. Another common region is the brain and may lead to hemorrhagic stroke   Cigarette smoking and hypertension increase the risk for aneurysms   Other causes include inflammation, infection, and injury to the aorta.   High blood pressure greatly increases the risk of aneurysm rupture, and aneurysm enlargement is usually without symptoms.

Exercise Management  (induced inadvertently by a physician or surgeon or by medical treatment or diagnostic procedures)  Aneurysms can be acquired from iatrogenic (induced inadvertently by a physician or surgeon or by medical treatment or diagnostic procedures) causes, typically as a surgical attempts to dilate a coronary vessel with atherosclerosis.   The main congenital cause of aortic aneurysms is Marfan's syndrome. Marfan's syndrome causes the aortic root to dilate immediately above the aortic valve. As dilatation progresses, the aortic valve begins to leak (aortic regurgitation), and the risk of Marfan's syndrome dissection increases.   The inherent risk of dissection or rupture from aneurysms is due to Laplace’s LawLaplace’s Law

Exercise Management Effects on the Exercise Response   If the aneurysm is the early phase of disease progression, there is usually no effect on the exercise response.   Biomechanical modeling of flow through an aortic aneurysm suggests that exercise may be detrimental in the progression of the disease.   Pulsatile flow through an aneurysm creates vortices and turbulence within the aneurysm that markedly increase wall stress (and increased risk for rupture). This can also induce an inflammatory response in smaller arterioles and promote atherosclerosis

Exercise Management Effects on the Exercise Response   It should be noted that while exercise training may modify the systemic inflammatory state, modify hypertension, and other hemodynamic conditions, it is unknown if exercise reduces aneurysm size.   In rare circumstances exercise training has been associated with aneurysm ruptures, and some ruptures have been among individuals with Marfan’s Syndrome.   Thus, pharmacologic stress testing may be more appropriate for patients with aneurysms than traditional exercise stress testing.

Exercise Management Effects of Exercise Training   To the extent that exercise increases blood pressure, exercise increases the tension on the wall of an aneurysm and so increases the risk of dissection or rupture for an already weakened aneurysm.   There is new evidence that intermittent periods of exercise (increased wall stress) can improve vascular function and possibly diminish aneurysm expansion rates   Exercise will diminish the relative risk of the risk factors that promote aneurysms (hypertension, inflammation, and hyperlipidemia – atherosclerosis)   Thus, a conservative approach to exercise training is warranted with the knowledge of the inherent risk of exercise and aneurysms (especially exercise intensity).

Exercise Management Management   For people diagnosed with an aneurysm, the key step in medical management is to follow the progress of the enlarged area. This might involve echocardiography, abdominal ultrasound, magnetic resonance imaging, or (less and less commonly) angiography.   The next most important step is to aggressively treat the risk factors that underlie the disease.

Exercise Management Management   Aneurysm diameter is progressive and should be tracked. Decisions regarding surgery for aneurysm repair should be made by a vascular physician, when appropriate.when appropriate

Exercise Management Recommendations for Exercise Testing (Table 16.1, p.123, next slide)   In general, people with known aneurysms of any type should not undergo any form of maximal exercise testing.   Submaximal stress tests can be used to optimize therapeutic control of heart rate and blood pressure (double product)   Stress tests can help adjust medications so that pulse rate does not rise above 100 contractions/min (adults).

Exercise Management

Recommendations for Exercise Programming (Table 16.2, p.124, table below)   Exercise should me limited and restricted to low end cardiovascular work ( ex. Bowling)   The larger the diameter of the aneurysm relative to the normal diameter of the vessel, the more exercise should be restricted.   Aerobic activity should be limited to moderate to low intensity.   Resistance training should be low intensity with aortic aneurysms, and avoided in cerebral aneurysms.

Exercise Management Recommendations for Exercise Programming (Table 16.2, p.124, next slide)   Special Considerations:   1) Increased risk of aneurysms in athletes with Marfan’s Syndrome   2) Individual’s with aortic aneurysms may safely exercise with low-moderate intensity exercise (50- 70% HRR) but those with cerebral aneurysms should avoid HR > 100 bpm.

Exercise Management

End of Presentation