Accelerated Diagnostic Protocol Driven Chest Pain Units: An Effective But Underutilised Potential

Abstract

Background: This study aimed to review the impact of several changes in August 2012, to the management of patients presenting with acute undifferentiated chest pain, with a possible diagnosis of acute coronary syndrome. Methods: This was a retrospective, observational, single centre study in Christchurch Hospital, New Zealand. Results from April 2011 and April 2014 were compared following these changes:1.Switching from conventional cardiac troponin I to high sensitivity cardiac troponin I (hs-cTnI)2.An accelerated diagnostic protocol (ADP) - low risk patients (modified TIMI = 0, negative serial hs-cTnI at 0h and 2h, non-ischaemic ECG) discharged with outpatient stress testing within 72 hours3.A Chest Pain Unit (CPU) managing low to intermediate risk (modified TIMI = 0–3) patients. End points were discharge within 6 hours/median length of stay (MLOS) in those with non-cardiac chest pain (NCCP) and 1 year death/acute myocardial infarction Results: There were 108 of 300 (36.0%) chest pain admissions in April 2011 diagnosed with NCCP, MLOS 23.43 hours, 20 (18.5%) discharged within 6 hours, 1 year adverse event rate 10 (9.3%). There were 137 of 341 (40.2%) admissions in April 2014 diagnosed with NCCP, MLOS 20.45 hours, 13 (9.5%) discharged within 6 hours. 11 of those with NCCP were CPU patients with MLOS of 6.58 hours. 1 year adverse event rate was 3 (2.2%). MLOS was effectively reduced by one third for CPU patients. Conclusion: ADP driven CPUs are safe alternative was to manage acute patients presenting with undifferentiated chest pain. MLOS was effectively reduced by one third for CPU patients. However, the true cost-effective benefits remain unclear due to underutilisation.