Interpretation of immediate exercise treadmill test: Interreader reliability between cardiologist and noncardiologist in a chest pain evaluation unit

Study objective: To determine whether attending physicians in a chest pain evaluation unit (CPEU) can perform and interpret exercise testing with the same accuracy as cardiologists. Methods: Between January 1996 and November 1998, immediate exercise tests were performed and interpreted by internists with additional training in exercise testing who serve as attending physicians in a CPEU at a large university medical center. For quality assurance, all tests were overread by a cardiologist. Test results were compared for each reader, and all tests with discrepant readings were reinterpreted by an independent cardiologist who was blinded to the previous results. Patients' clinical course was monitored for at least 30 days after exercise testing. Results: The study group consisted of 645 patients (347 men, 298 women). Discrepant interpretations were found in 11 (1.7%) patients. The agreement was 98.4% (κ value 0.9618). The majority of discrepancies were insignificant and were based on subtle differences in the definition of a nondiagnostic test or the degree of ST-segment shift. Of the 11 discordant readings, the blinded cardiologist concurred with 5 (45%) of the CPEU interpretations and 4 (36%) of the cardiologist interpretations. In 2 cases, there was disagreement by all 3 interpreters. There was no cardiac morbidity or mortality of any patient with a discrepant reading. Conclusion: Our results suggest that noncardiologists serving as attending physicians in a CPEU can accurately interpret exercise tests and overreading by cardiologists for quality assurance is unnecessary.