ACC: Stress testing in womenits a mans world
CHICAGO—A case study on a patient with dyspnea raised questions about evaluation for ischemia in women and protocols for stress testing March 26 at the 61st annual American College of Cardiology (ACC) scientific sessions.

Janet Long, MSN, of the Rhode Island Cardiology Center in Providence, R.I., presented the case of a 63-year-old woman with exertional dyspnea that had worsened over three months. The patient was under treatment of hypertension, didn’t smoke, was a normal weight and had a family history of MI through her father, who died of the disease at age 47. The Framingham Risk Score for coronary artery disease (CAD) placed her at intermediate risk. Long noted that non-chest pain symptoms such as dyspnea may be consistent with CAD and be considered an anginal equivalent.

The patient’s cardiac exam was unremarkable and an EKG showed normal sinus rhythm. The next step was choosing the proper stress test to evaluate ischemia, in this case, an exercise treadmill test. Results based on the Bruce protocol indicated no ischemic EKG changes.

Nanette K. Wenger, MD, of the cardiology department at Emory University School of Medicine in Atlanta, said the case study illustrated a number of important issues for cardiologists. “We have come to realize more and more in women, and in men, that anginal equivalence is fairly common,” Wenger said. She noted the case reflects the progression in the ischemic cascade, from myocardial stiffening, diastolic dysfunction and later problems with filling.

“This is the time of the development of ischemia when you are likely to have the weakness, the tiredness, the shortness of breath,” she said. Many patients may not progress to the development of angina. “More and more we are beginning to say that new onset of symptoms should be very concerning for women and men and dyspnea may be a very common presentation,” Wenger said.

She added that in the original Framingham cohort, researchers ignored angina because they didn’t associate it with mortality. But as demonstrated in a recent study, women are less likely to present with chest pain, and younger women who presented without chest pain had a higher hospital death rate (JAMA 2012;307[8]:813-822).

“They [Framingham] missed a lot of women because they looked at only the classic central chest pain and did not look at the anginal equivalence,” she said, adding that a central message is that ischemia can kill. “Stable ischemic heart disease is not benign.”  

Wenger also questioned whether the Bruce protocol was appropriate in some cases. The protocol calls for an initially modest speed at a modest incline, both of which increase every three minutes up to 27 minutes. She pointed out that the test was designed in a study of healthy adult men and said that even at the beginning phase it may be a high activity level for some women and men.

“We could get much more mileage from treadmill testing, using a more gradual protocol,” she suggested. Ideally, she added, physicians prefer durations of up to six minutes to observe changes with exertion. Using “the very appropriate plain old treadmill test with a gradual protocol, particularly in a patient whose exercise tolerance is borderline,” she said, might provide important additional diagnostic or prognostic data.