Non-physician supervision of cardiopulmonary exercise testing in chronic heart failure: Safety and results of a preliminary investigation

Purpose. In the current era of efficient use of personnel and cost containment, the use of non-physicians in selected roles previously occupied exclusively by physicians has become increasingly prevalent. Traditionally, physicians have directly supervised graded exercise testing of patients with chronic heart failure. The purpose of this prospective pilot investigation was to determine the safety and results of non-physician supervised exercise testing of these high-risk patients. Methods. Two hundred eighty-nine consecutive outpatients (211 men, 78 women) with left ventricular ejection fractions of ≤35% were referred for cardiopulmonary exercise testing. Symptom-limited treadmill graded exercise tests were supervised by paramedical personnel with a physician immediately available, but not present in the lab. Results. Nonsustained ventricular tachycardia was present during exercise in approximately 20% of patients. Test-limiting hypotension was documented in 5% of subjects. Only one serious event occurred during the 289 exercise tests, an episode of ventricular fibrillation with a successful resuscitation outcome. Peak exercise respiratory exchange ratio averaged 1.10 ± 0.14, consistent with a near-maximal patient effort. Peak oxygen uptake was 18 ± 5 ml/kg/min. Conclusions. Supervision of cardiopulmonary graded exercise testing in properly screened patients with severe systolic left ventricular dysfunction by experienced non-physicians appears to be reasonably safe and the results are suitable for clinical decision making. Such a practice is an attractive cost-containment strategy and deserves further investigation.