Extending the no objective testing rules to patients triaged by the European Society of Cardiology 0/1-hour algorithms

Aims: After rule-out of non-ST elevation myocardial infarction (NSTEMI) with the European Society of Cardiology (ESC) 0/1 h-algorithms, it is unclear which patients require further anatomical or functional cardiac testing. To test the safety and efficacy of the no-objective-testing (NOT)-rules after NSTEMI rule-out by the ESC 0/1 h-algorithms.

Methods and results: International, prospective, diagnostic multicentre study enrolling adult patients presenting with chest pain to the emergency department. Central adjudication of final diagnosis by two independent cardiologists using information including cardiac imaging. Primary endpoints were the safety and efficacy of the NOT-rules for the rule-out of major adverse cardiovascular events (MACE). Secondary endpoints included 365-day and 2-year MACE. Among 4804 and 4569 patients with available 0/1 h high-sensitivity cardiac troponin (hs-cTn)T-Elecsys or hs-cTnI-Architect concentrations, 2783 (58%) and 2252 (49%) were eligible for application of the NOT-rules after rule-out of NSTEMI by the ESC hs-cTnT/I-0/1h-algorithm. The first rule identified 26% of patients with a sensitivity of 100% (95%CI 98.3-100%) and a negative predictive value (NPV) of 100% (95% CI, n.c.). The second and third rules both identified 31% of patients with a sensitivity of 99.5% (95% CI 97.4-99.9%) and a NPV of 99.9% (95% CI 99.2-99.9%). Similar findings emerged for hs-cTnI. High safety was confirmed for rule-out of 365-day and 2-year MACE and proven to be superior to the HEART Score.

Conclusion: All three NOT-rules performed very well for rule-out of MACE. The third NOT-rule best balanced feasibility, safety, and efficacy by identifying nearly one out of three patients as low-risk and may not require further cardiac testing. https://clinicaltrials.gov/ct2/show/NCT00470587.