Safety of exercise testing volunteer subjects: The lipid research clinics’ prevalence study experience

Previous reports of the complication rates of near-maximal and maximal exercise tests have involved the limited experience of one or a few coordinated laboratories or have represented surveys of facilities employing diverse protocols and instrumentation. We report the experience of 12 widely separated laboratories employing identical protocols and equipment. Near-maximal graded treadmill exercise tests were performed by 9,464 men and women participants in the Lipid Research Clinics’ Prevalence Survey. Subjects were randomly selected (N = 5,317) or were hyperlipidemic (N = 4,147). Participants exercised to 85% to 90% of age-adjusted predicated maximal heart rate unless medical contraindication to continued exercise or limiting symptoms occurred first. Electrocardiographic data, blood pressure, appearance, and symptoms were monitored at rest and during exercise and recovery. No deaths, myocardial infarctions, or cardiac arrests occurred during or within 24 hours following testing. Runs of two or more ventricular premature complexes occurred in 127 tests, but all spontaneously reverted to normal sinus rhythm. Ten subjects experienced chest discomfort that lasted 10 minutes or longer without further complications. Atrial fibrillation, vasovagal collapse, and nausea with chest pain lasting 24 hours without sequelae occurred once each. These data indicate that near-maximal and maximal testing can be performed safely with proper screening and monitoring.