Q: I am 84 years old, but I have always been physically active. I received a pacemaker in 1988, and both hips were replaced in 1999. Recently, I find myself getting out of breath with mild activity, such as climbing stairs, swimming fast, etc. My family doctor says "old age" and he is sending me for cardiology and lung exams. I would appreciate any suggestions you may have about my condition and how I can be as healthy and physically active as possible in the years to come.
A: It’s wonderful that you want to continue to exercise. Studies show that not only does exercise preserve cardiovascular and pulmonary capacity, improve muscle tone, and maintain bone density, but exercise may also prevent or postpone the onset of dementia.
There are indeed physiologic changes that affect the heart as a person grows older that may be affecting you, as well. Arteries become more stiff, requiring the heart to pump harder to achieve the same result. The heart muscle may hypertrophy (grow thicker) with age, to try to overcome this resistance. These changes alter the pressures and volumes in the four different chambers of the heart. Altered pressures and volumes mean that during exercise, the heart in an older person may be less efficient. The end result is that the maximum level of exertion an older person achieves may decline with time, even with continued training.
This being said, a sharper decline, such as the development of shortness of breath with moderate (not maximal) exertion, needs to be evaluated promptly. Other problems could be superimposed on the body’s gentle aging process. These may include changes in your pacemaker function, such as degradation of the lead contact, or reaching the lifespan of the battery.
Other changes could include dilation (stretching) of your heart chambers, or possibly narrowed or leaky heart valves, which could lead to heart failure. Ischemia (lack of oxygen to parts of the heart resulting from atherosclerosis of the major arteries of the heart) could also show up as shortness of breath. If you smoked in the past, your lung function may have declined more than the average person, causing excessive shortness of breath with exertion.
Tests that may be helpful could include your complete blood count, blood chemistries to measure kidney function, electrocardiogram, chest X-ray, and evaluation of your pacemaker by your cardiologist in the office. A telephonic check (evaluation over the telephone) would not be sufficient if you believe pacemaker malfunction is contributing to the shortness of breath. Other tests, if indicated, may include spirometry, arterial blood gas, echocardiogram, and exercise stress test.