Purpose: To determine if the ACC/ECC guidelines (1991) properly stratify patients according to risk of arrhythmia, defined as a single event on cardiac monitoring, and benefit, defined as a subsequent management change from a recorded telemetry event.
Subjects and methods: In 2003, a prospective study of 217 consecutive patients admitted to a 24-bed telemetry unit was conducted for 25 days at a major academic hospital. Patients were categorized per ACC/ECC guidelines as appropriate (class I & II) or inappropriate (class III) based on a non-cardiologist admission diagnosis. A cardiologist-led group then reclassified patients at the time of admission using a brief interview. Continuous telemetry-recorded arrhythmias and resultant management changes were reviewed and recorded daily. Subgroup analysis of patients admitted with a chief complaint of chest pain was also performed. In 2004, after this trial was performed, the American Heart Association released a scientific statement updating practice standards for ECG monitor; however, this paper is based upon the original 1991 ACC/ECC guidelines.
Results: Reclassification significantly decreased the percentage of all class I & II patients from 91% to 71% (P<0.001) and the percentage of class I & II patients with chest pain from 100% to 58% (P<0.001) without increasing the percentage of arrhythmias occurring in class III patients. Class II patients had a statistically significant higher percentage of arrhythmias than class I and III patients before and after reclassification (P<0.001 and P<0.001, respectively). Management changes occurring as a direct result of telemetry events were higher in class II than class I or III patients before and after reclassification (P = 0.01 and P = 0.03). Life-threatening arrhythmias (sustained ventricular tachycardia or ventricular fibrillation) occurred in 1% of the 216 patients enrolled in this study.
Conclusions: (1) Cardiology input using ACC/ECC guidelines and a brief interview at admission safely reduced total admissions primarily by identifying low risk chest pain admissions inappropriate for inpatient telemetry monitoring. (2) Life threatening arrhythmias occurring in patients admitted to telemetry are rare.