Supervising Exercise and Stress Testing in Contemporary Practice

Over the last several decades, clinical exercise testing, as well as pharmacological stress testing, has evolved considerably. Thirty and 40 years ago, details from the exercise hemodynamics and physiological responses, and the various details of the exercise electrocardiogram (ECG), were used heavily in patient management decisions. However, over recent decades, it has been recognized that coronary plaque rupture, as opposed to simply severe coronary obstructive atherosclerotic plaque, even often involving non-obstructive coronary lesions, is the leading pathophysiological mechanism for most acute coronary syndromes (ACS). Therefore, the use of treadmill and stress testing has evolved from detecting severe obstructive coronary lesions at risk of ACS to now assessing the risk in patients with atypical chest pain syndromes and overall prognosis in many groups of patients with or at risk for cardiovascular (CV) diseases. Also, currently in most major medical centers and CV practices, a minority of stress tests are performed with only ECG but rather are often combined with some imaging modality, typically stress echocardiography or stress nuclear imaging. Nevertheless, stress testing remains a major part of clinical and CV practices.

In the early days of stress testing, these tests were usually performed with the attending physician as the main person performing and monitoring the test as well as interpreting the test and making decisions on the patient’s subsequent care based upon the test results, usually performed as an exercise ECG stress test. Currently, however, although the physician generally provides the interpretation of the test and finalizes the official stress test report, these tests are generally monitored by ancillary medical personnel, including nurses, exercise physiologists, and other health professionals trained to perform and monitor these stress tests.

Clearly, physicians and even specialists in CV diseases do not always have the greatest expertise in physical activity and recommendations regarding exercise,¹ and often other medical personnel can provide substantial expertise in the area of exercise physiology and hemodynamics above and beyond the expertise provided by physicians, even CV specialists. Therefore, many non-physicians provide expertise that is complementary and additive to the experiences and expertise of many physicians and CV specialists. Currently, as reviewed in the current American Heart Association (AHA) Scientific Statement from Myers and colleagues,² most stress tests, including exercise treadmill stress tests, are administered and monitored by non-physicians. Therefore, this document is needed and timely to provide guidance for the clinical performance and supervision of exercise testing by non-physicians in the current era, and extends prior recommendations from the AHA, American College of Cardiology, and other important organizations, such as the American College of Sports Medicine and the American Association of Cardiopulmonary Rehabilitation and Prevention, who have also provided important recommendations in this area.^3-6

As documented in this expert statement, many groups of non-physicians typically supervise stress tests depending on the needs at various institutions, and these non-physicians include exercise physiologists, physical therapists, registered nurses, nurse practitioners, physician assistants, and other health professionals. Regardless of who is supervising the test, the ultimate responsibility falls on the supervising physician, who may be seconds or minutes away, depending on the institution and the clinical situation. The physician also has the responsibility to assure that the "team" performing and monitoring the test is qualified to effectively and safely perform such testing.

Although the current AHA statement provides guidance for physicians and non-physicians who are monitoring stress testing, this document also provides support for practices that have been routine at major medical centers for most of the past two decades. Additionally, although I agree with most of the major points made in this extensive document, it should be emphasized that this is an expert statement from a very skilled and well-recognized writing group that provides important suggestions and guidance, but there still will be considerable variability in many practices. For example, in Table 2, the writing group lists several scenarios regarding patients requiring personal physician supervision, typically meaning that the physician is directly in the exercise room during the testing. Although this would typically be true in several of the cases listed in Table 2, and the physician would likely be present for monitoring patients with recurrent exertional syncope or recent exertional sudden cardiac death, this may not be the practice at all centers for the full list of patients in Table 2. For example, at many larger centers, especially in academic institutions, the supervising CV specialist, and several other CV specialists and CV fellows, may be in a reading room within 5-10 seconds of the testing room. For an asymptomatic or minimally symptomatic patient with significant, but not critical, aortic stenosis, for example, the supervising nurse or other non-physician monitoring the test may speak directly with the supervising physician prior to the start of such tests, and this physician would be immediately available, but at many institutions may not be directly in the room for the duration of the test. Nevertheless, the expert writing group has provided very valuable suggestions to aid in the practice of stress testing in our modern era.

Finally, it should be emphasized that although very few deaths occur from stress testing,^7-9 there are a modest number of "significant" complications, which could potentially increase in the future as this technology is being applied to "sicker" patients, including patients with advanced heart failure (e.g., patients with left ventricular assist devices), advanced valvular heart disease, and at very elderly ages.^2,7-9 As reviewed in this extensive expert statement, we all recognize that we live in a very legal-oriented, litigious society. Although relatively few major lawsuits likely occur due to the details of stress testing,^2,10 this remains a legitimate concern for all physicians and non-physicians working with such testing. As such, this document provides substantial background information and guidance that will be extremely helpful to many clinicians, but again it must be recognized that this represents a statement from an expert writing group rather than a definitive guideline to handle the practice at every institution and CV and non-CV practices in the United States and the rest of the world. Therefore, some variability from this document may still be well within the effective and safe practice of stress testing and be the standard of care in various parts of the world, including in excellent CV and non-CV practices in the United States.