As I have so often stated, “Exercise is the best medication.” By that, I mean that it treats all the risk factors of heart disease including high blood pressure, high cholesterol, diabetes, and obesity. Exercise is not just a strategy to keep healthy, it might be the true cornerstone of how we evaluate women’s hearts. Women often suffer from microvascular disease, leading to subtle symptoms, difficulty of diagnosis, less treatment, and worse outcomes. The ability to exercise might truly be the cornerstone in diagnosing heart disease in women. In fact, functional capacity may have a more critical role in how we evaluate women’s hearts than we have appreciated.
This fact is apparent in the AHA 2016 Scientific Statement entitled, “Importance of Assessing Cardiorespiratory Fitness in Clinical Practice: A Case for Fitness as a Clinical Vital Sign,” published in Circulation. This guideline describes that a woman’s (and man’s!) ability to exercise could be the key to understanding the health of her heart. In fact, a lack of cardiorespiratory fitness is most likely a stronger predictor of mortality than the traditional major risk factors such as smoking, hypertension, high cholesterol, and type 2 diabetes.
A cardiopulmonary exercise test (CPET) is a diagnostic test that can diagnose not only microvascular disease, but also preclinical dysfunction, and should be part of a standard evaluation of our women patients. Studies have shown that “prescribing” exercise alone, based on the CPET, can change outcomes, as for each 1-MET increase of exercise and cardiorespiratory fitness, there was a 21% lower cardiovascular disease mortality for women (and men) who were less than 60 years old at baseline.
In light of the challenges in diagnostic testing in women, a simple cardiopulmonary stress test might be the answer, especially based on these issues:
- The beginning of heart disease in women is not detected through typical testing, such as a stress test, that looks for blockages 70% or greater. Although the stress test could determine functional capacity, it does not detect the stage at which disease begins and is most preventable—endothelial dysfunction. Screening tests looking for plaque in the arteries, such as coronary artery calcium scores or carotid dopplers, can identify those women with pre-clinical disease, who have risk factors or a family history, but our goal should be to find disease before it starts.
- Unclear symptoms of fatigue, shortness of breath, jaw pain, abdominal pain, or back pain can be easily evaluated through a CPET, without radiation exposure or added imaging.
- Heart disease in women typically begins with endothelial dysfunction, which can often be first detected during pregnancy. With later symptoms, if we are able to diagnose endothelial dysfunction and address it, then we can treat and prevent it early.
We are at the point where we must change the paradigm to a preventative strategy. Diagnosis based on cardiorespiratory fitness may be the key. Just imagine the ramifications for early detection in women. Heart disease would no longer be her No. 1 health threat. Imagine that!