The Manchester Acute Coronary Syndromes (MACS) decision rule for suspected cardiac chest pain: derivation and external validation

Abstract

ObjectiveWe aimed to derive and validate a clinical decision rule (CDR) for suspected cardiac chest pain in the emergency department (ED). Incorporating information available at the time of first presentation, this CDR would effectively risk-stratify patients and immediately identify: (A) patients for whom hospitalisation may be safely avoided; and (B) high-risk patients, facilitating judicious use of resources.MethodsIn two sequential prospective observational cohort studies at heterogeneous centres, we included ED patients with suspected cardiac chest pain. We recorded clinical features and drew blood on arrival. The primary outcome was major adverse cardiac events (MACE) (death, prevalent or incident acute myocardial infarction, coronary revascularisation or new coronary stenosis >50%) within 30 days. The CDR was derived by logistic regression, considering reliable (κ>0.6) univariate predictors (p<0.05) for inclusion.ResultsIn the derivation study (n=698) we derived a CDR including eight variables (high sensitivity troponin T; heart-type fatty acid binding protein; ECG ischaemia; diaphoresis observed; vomiting; pain radiation to right arm/shoulder; worsening angina; hypotension), which had a C-statistic of 0.95 (95% CI 0.93 to 0.97) implying near perfect diagnostic performance. On external validation (n=463) the CDR identified 27.0% of patients as ‘very low risk’ and potentially suitable for discharge from the ED. 0.0% of these patients had prevalent acute myocardial infarction and 1.6% developed MACE (n=2; both coronary stenoses without revascularisation). 9.9% of patients were classified as ‘high-risk’, 95.7% of whom developed MACE.ConclusionsThe Manchester Acute Coronary Syndromes (MACS) rule has the potential to safely reduce unnecessary hospital admissions and facilitate judicious use of high dependency resources.

High-Sensitivity Cardiac Troponin T Concentrations below the Limit of Detection to Exclude Acute Myocardial Infarction: A Prospective Evaluation

“…The primary objective of the study was to validate a clinical decision rule, which has been reported separately (8 ).…”

“…In the emergency department (ED), 8 highsensitivity cardiac troponin has been shown to have greater diagnostic sensitivity at the time of presentation than standard assays (2 ). However, even with highsensitivity assays, use of the traditional diagnostic cutoff set at the 99th percentile yields a diagnostic sensitivity of only approximately 90% at the time of presentation, and many studies used less-sensitive gold standards as a comparator, possibly leading to inflated estimates of diagnostic sensitivity by this approach (3 ).…”

Redesigning the diagnostic pathway for chest pain patients in emergency departments

“…Alternatives to this strategy have been proposed taking advantage of the fact that in patients with very low pre-test probability of AMI and Acute Coronary Syndrom (ACS), very low baseline cTn levels make the possibility of AMI highly unlikely [8,11,31,37]. If incorporated in the diagnostic pathway, such an early rule-out protocol could help avoid unnecessary tests and admissions for patients who do not have AMI but present with chest pain and have had cTn measured at presentation.…”

“…Project results indicated significant improvements in reducing the number of hospital admissions [28]). Finally, recent studies report that some low risk patients could be safely discharged on the basis of a single negative test if they present more than three hours after the onset of worst symptoms and have very low levels of cTn [8,11,31,37]. Our study aims to support EDs to effectively manage staff workload and to reduce the number of avoidable admissions from ED into hospital.…”

The Discussion of the Problems of the Use of Markers of Myocardial Necrosis in the Framework of the Russian National Congress of Cardiology (September 20-23, 2016)

“…в последние годы появились диагностикумы для качественного определения уровня сердечного БСЖК и тропонина I. А в 2014 году в Ан-глии был разработан диагностический алгоритм MACS [18], в котором использована оценка клинических, электрокарди-ографических данных, а также определение уровня БСЖК и высокочувствительного тропонина для стратификации риска пациентов, доставленных в отделение скорой помощи с подо-зрением на острый коронарный синдром. По мнению авто-ров, данный протокол имеет преимущество для определения пациентов низкого риска в течение 4-часового временного окна с отрицательной предсказательной значимостью 99,8 %.…”