Author + information
- Atul Anand,
- Andrew Chapman,
- Anoop Shah,
- Philip Adamson,
- Amy Ferry,
- Dennis Sandeman,
- Fiona Strachan,
- David Newby and
- Nicholas Mills
Background: The safety and efficacy of pathways using high-sensitivity cardiac troponin I to risk stratify and diagnose myocardial infarction (MI) remain uncertain in older patients.
Methods: In 4,739 consecutive patients with suspected acute coronary syndrome stratified by age, we evaluated the performance of a risk stratification threshold of <5 ng/L at presentation, and sex-specific 99th centile diagnostic thresholds on serial testing. Events were independently adjudicated by two cardiologists.
Results: In patients with troponin concentrations <99th centile at presentation (n=3,799), the negative predictive value of a troponin <5 ng/L for index or subsequent type 1 MI or cardiac death within 30 days was similar in those under 75 (99.6%, 95% CI 99.3-99.8, n=2,863) and over 75 (99.5%, 95% CI 98.4-100, n=936), but identified more younger patients as low risk (71% vs 31%, p<0.001). Whilst the specificity of the 99th centile for type 1 MI was lower in older patients (75% vs 94%), the diagnosis was more common (Fig A). In logistic regression modelling adjusting for sex, renal function and comorbidity, age was consistently the strongest predictor of type 1 MI (Fig B).
Conclusions: Risk stratification thresholds to rule out MI at presentation are safe in the elderly, but can be applied to fewer patients. Whilst the specificity of the 99th centile for a diagnosis of type 1 MI is lower in older patients, this group are at highest risk and the application of age-specific thresholds would reduce diagnostic sensitivity.
Poster Hall, Hall C
Saturday, March 18, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Acute Coronary Syndromes, Diagnosis, Management and Outcomes
Abstract Category: 2. Acute and Stable Ischemic Heart Disease: Clinical
Presentation Number: 1253-339
- 2017 American College of Cardiology Foundation