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Feasibility of determining myocardial infarction type from medical record review
Ken S Woo1, William A Ghali, Danielle A Southern
1Department of Medicine, University of Alberta, Edmonton, Canada.
Insights
Hospital records often fail to consistently document whether a myocardial infarction (MI) was ST segment elevation MI (STEMI) or non-ST segment elevation MI (NSTEMI). This inconsistency hinders retrospective health research on MI care.
Area of Science:
- Cardiology
- Health Services Research
- Medical Informatics
Background:
- Hospital discharge data are crucial for health research.
- Distinguishing between ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI) is clinically important.
- The accuracy and consistency of MI type documentation in medical records require investigation.
Purpose of the Study:
- To assess the extent to which myocardial infarction (MI) types (STEMI vs. NSTEMI) are recorded in patient medical records.
- To evaluate the consistency of MI type designation within individual patient records.
Main Methods:
- A review of medical records for all MI patients admitted to a Canadian tertiary care center between April 2000 and March 2001.
- Assessment of STEMI and NSTEMI documentation across admission history, progress notes, CCU summary, and discharge summary.
- Analysis of documentation completeness and consistency of MI type designation.
Main Results:
- MI type was mentioned in fewer than half of chart sections.
- Overall, MI type could be determined in 81.1% of cases when information was combined.
- Consistent STEMI designation occurred in 48.7% of cases, NSTEMI in 32.4%, with discrepancies in 10.5% and missing data in 8.4%.
Conclusions:
- The recording of MI type (STEMI/NSTEMI) in hospital records is both incomplete and inconsistent.
- This lack of consistent documentation poses significant challenges for retrospective health services research on MI processes and outcomes.
Background:
Hospital discharge data are used extensively in health research. Given the clinical differences between ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI), it is important that these entities be distinguishable in a medical record. The authors sought to determine the extent to which the type of MI is recorded in medical records, as well as the consistency of this designation within individual records.
Methods:
Records of all MI patients admitted to a tertiary care centre in Canada from April 1, 2000, to March 31, 2001, were reviewed. Documentation and consistency of the use of the terms STEMI (Q wave, ST elevation or transmural MI) or NSTEMI (non-Q wave, subendocardial or nontransmural MI) were assessed in the admission history, progress notes, coronary care unit summary and discharge summary sections of each record.
Results:
Missing data were common; each chart section mentioned MI type in fewer than one-half of charts. When information was combined, it was possible to determine the type of MI in 81.1% of cases. MI type was consistently described as STEMI in 48.7% of cases, and as NSTEMI in 32.4%. Of concern, MI type was discrepant across sections in 10.5% of cases and missing entirely in 8.4% of cases.
Conclusions:
The designation of MI cases as STEMI or NSTEMI is both incomplete and inconsistent in hospital records. This has implications for health services research conducted retrospectively using medical record data, because it is difficult to comprehensively study processes and outcomes of MI care if the type cannot be retrospectively determined.
