Marburg Heart Score and INTERCHEST show modest discrimination comparable to standard protocol for acute chest pain triage.

OBJECTIVES: To assess whether the Marburg Heart Score (MHS) and INTERCHEST score may improve telephone triage of chest pain by providing better diagnostic discrimination compared with the triage protocol from the Netherlands Triage Standard (NTS). DESIGN: Prospective diagnostic accuracy study. SETTING: Large regional out-of-hours primary care (OOH-PC) facility in Alkmaar, the Netherlands. PARTICIPANTS: A total of 1254 eligible patients contacted the OOH-PC facility (median age 56.0 years, 57.9% female) between December 2022 and May 2023. The study was completed and verbal informed consent obtained in 280 (22.3%) patients. INTERVENTIONS: Triage assistants asked study questions in addition to the NTS protocol to complete the MHS and INTERCHEST score. PRIMARY AND SECONDARY OUTCOME MEASURES: Discrimination (C-statistics) and diagnostic test properties (eg, sensitivity/specificity) were used; the reference standard was the occurrence of a major event (ie, composite of all-cause mortality, and urgent cardiovascular and non-cardiovascular conditions) or acute coronary syndrome (ACS) within 6 weeks. RESULTS: A major event occurred in 36 patients (12.9%), including 13 (4.6%) ACS cases. For predicting major events, the MHS and INTERCHEST scores showed C-statistics of 0.67 (95% CI 0.57 to 0.77) and 0.64 (95% CI 0.54 to 0.74), respectively, compared with 0.62 (95% CI 0.53 to 0.71) for the NTS protocol. For ACS, C-statistics were 0.62 (95% CI 0.45 to 0.79), 0.59 (95% CI 0.43 to 0.75), and 0.62 (95% CI 0.49 to 0.75) for MHS, INTERCHEST and NTS, respectively. Regarding test characteristics, the MHS and INTERCHEST score showed higher point estimates for specificity (27.9% and 26.6%) vs the NTS (19.7%), but at the expense of lower sensitivity (88.9% and 86.1% versus 97.2%) for major events. For ACS, a similar pattern was observed (specificity 26.2% and 25.5% vs 18.4; sensitivity 84.6% and 84.6% vs 100.0%). CONCLUSIONS: Simple clinical decision rules (MHS and INTERCHEST) have comparable, modest discriminative ability and diagnostic properties compared with the current protocol for telephone triage of acute chest pain in Dutch OOH-PC. TRIAL REGISTRATION NUMBER: Netherlands Trial Register (TRACE - NL-OMON20102).