A short-cut review was carried out to establish whether the Manchester Acute Coronary Syndromes (MACS) and Troponin-only MACS (T-MACS) decision aids can safely rule out acute coronary syndromes in patients presenting to the ED with suspected cardiac chest pain. Six studies were directly relevant to the question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that both rules have high sensitivity for acute coronary syndromes, including the detection of major adverse cardiac events at 30 days. The original MACS algorithm may have marginally greater sensitivity than T-MACS but has inferior specificity and requires the use of a biomarker assay (for heart-type fatty acid binding protein) that is not currently widely used in practice.