Correspondence

A New Stress for Stress Tests

N Engl J Med 1994; 330:869-870March 24, 1994

Article

To the Editor:

A 71-year-old man was recently referred to our echocardiography laboratory for a stress test with dobutamine. Initially, he appeared to be a calm, soft-spoken man. His resting heart rate was 81 beats per minute. During the first dose of dobutamine (5 μg per kilogram of body weight per minute), his base-line heart rate was 92 beats per minute. He then engaged one of the physicians in a discussion about Hillary Clinton and the Clinton administration's proposed health care reform. It was clear from the conversation that the patient was strongly opposed to it. While he was talking about health care reform, his heart rate increased from 92 to 117 beats per minute. When he stopped, his heart rate rapidly decreased to 94 beats per minute. With an increase in the dose of dobutamine to 10 μg per kilogram per minute, the patient's base-line heart rate was 100 beats per minute. When the discussion of health care reform resumed, his heart rate increased to 124, and when the discussion stopped, his heart rate rapidly decreased to 105. At a dose of 20 μg of dobutamine per kilogram per minute, the patient's base-line heart rate was 117; it increased to 147 during the discussion of the proposed reform. When the discussion ended, his heart rate decreased to 124 (Figure 1Figure 1Effect of Dobutamine and Discussion of Health Care Reform on Heart Rate in a 71-Year-Old Man.). The study was terminated at this point, since the target heart rate had been achieved.

In this patient, the additional stress induced by conversation about Hillary Clinton and the administration's proposal for health care reform caused an average increase in the heart rate of 26.3 ±3.2 beats per minute as each dose of dobutamine was administered. The discussion resulted in attainment of the target heart rate at a lower dose of dobutamine than might otherwise have been possible.

When a stress test with dobutamine is conducted, the addition of emotional stress induced by a discussion of health care reform may lower the risk of untoward effects of high-dose dobutamine. With judicious application of the discussion, we were able to complete the stress test in a cost-efficient manner.

Further studies are needed to confirm these promising but preliminary findings.

Mark R. Gordon, M.D.
Candace D. Dick, M.D.
Charles A. Herzog, M.D.
Hennepin County Medical Center, Minneapolis, MN 55415