71 30-Day Major Adverse Cardiac Events After Enterprise Implementation of a Chest Pain Rapid Rule Out Process Utilizing High Sensitivity Troponin T

Abstract

The 30 day Major Adverse Cardiac Event (MACE) rate after implementation of a chest pain rapid rule out (CP RRO) process utilizing the new generation 5 high sensitivity troponin T (hs-TnT) is currently not known. Our objective was to compare the rate of patients returning to our health system with MACE within 30 days of low risk discharge from an emergency department (ED) visit for potential acute coronary symptoms before and after implementation of the process. The CP RRO process was implemented in step-wise fashion at 11 hospital-based EDs and 3 freestanding EDs between 7/6/17 and 2/18/18. Process was initiated either at triage or by attending provider. Initial hs-TnT was drawn on arrival, with repeat obtained 1 hour later and at least 3 hours post onset of pain. Patients were identified as low risk after meeting all of the following: no high risk history (unstable angina), no new ECG changes, modified HEART score (age + risk factors only) < 4, initial hs-TnT < 12 ng/l, and 1 hour delta hs-TnT < 3 ng/l. Clinical decision support was embedded into the electronic health record (EHR, EPIC) and decision trees were posted to aid interpretation. Final disposition was at the discretion of the attending physician. All encounters where patients had at least 2 troponins (either TnT or hs-TnT) obtained during an ED or ED and hospital visit were entered into a quality database from Clarity database by Business Intelligence. The presence of acute myocardial infarction (AMI), percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), and mortality within 30 days of discharge was recorded. Procedures were identified as planned if there was prior notation in the EHR or in the history of present illness of the index visit. Mortality were reviewed and classified by likely cause of death without knowledge of whether CP RRO process was utilized. A total of 2914, 4986, and 3614 patients were discharged in 2016, 2017, and 2018, respectively. The composite 30 day MACE rate was 0.30%, 0.28%, and 0.14%, respectively. This decreased to 0.069%, 0.100%, and 0.028%, respectively, when planned PCI and CABG as well as expected mortality were removed. The AMI 30 day MACE rate was 0.034%, 0%, and 0.014% Within the CP RRO patients, there was 1 NSTEMI, who subsequently underwent CABG within 30 days. There was 1 planned PCI and 3 planned CABGs. The 12 mortalities were classified as 0 cardiovascular; 6 DNR/palliative/hospice; 1 oncologic respiratory failure; 1 post operative complication; 1 opioid substance abuse; and 3 unknown etiologies. One of the unknown mortalities occurred after discharge with CP RRO. Use of our CP RRO process utilizing hs-TnT is associated with a very low rate of major adverse cardiac events in patients returning within 30 days to our health system.