Indicator Metadata

30-Day Acute Myocardial Infarction In-Hospital Mortality

Not applicable

The risk-adjusted rate of all-cause in-hospital death occurring within 30 days of first admission with a diagnosis of acute myocardial infarction (AMI)

For further details, please see the General Methodology Notes (PDF).

The risk-adjusted mortality rate (RAMR) is calculated by dividing the observed number of in-hospital deaths by the expected number of in-hospital deaths and multiplying by the Canadian average in-hospital death rate.

Unit of analysis for denominator cases: Episode of care

Place of residence or service

Rate - per 100

The following covariates are used in risk adjustment:
For a detailed list of covariates used in the model, please refer to the Model Specification (PDF) document.

Logistic regression

Description:
Total number of first AMI episodes in an 11-month period

Inclusions:

1. 1. Acute myocardial infarction (AMI) (ICD-10-CA: I21, I22; ICD-9/ICD-9-CM: 410) is coded as most responsible diagnosis (MRDx) but not also as a diagnosis type (2); or

   2. Where another diagnosis is coded as MRDx and also a diagnosis type (2), and a diagnosis of AMI is coded as a type (1) [type (C) for Quebec data] or type (W), (X) or (Y) but not also as type (2); or

   3. Where coronary artery disease (ICD-10-CA: I25.0, I25.1, I25.8, I25.9; ICD-9/ICD-9-CM: 429.2, 414.0, 414.8, 414.9) is coded as MRDx, AMI as type (1) [type (C) for Quebec data] or type (W), (X) or (Y) but not also as type (2); along with revascularization procedure (percutaneous coronary intervention—CCI: 1.IJ.50^^; 1.IJ.57.GT^^* ; 1.IJ.57.GU^^* ; 1.IJ.57.GQ^^ [this code is used for 2002–2003 to 2017–2018 data only]; 1.IJ.54.GQ-AZ [this code is used for 2006–2007 to 2008–2009 data only]; CCP: 48.02, 48.03; ICD-9-CM: 36.01, 36.02, 36.05; or coronary artery bypass—CCI: 1.IJ.76^^; CCP: 48.1^; ICD-9-CM: 36.1^)

2. Episodes involving inpatient care (Facility Type Code = 1). An episode may start or end in a day surgery setting. Episodes that both start and end in day surgery settings are not included.
3. Admission between April 1 and March 1 of the following year (period of case selection ends March 1 to allow for 30 days of follow-up)
4. Age at admission 18 years and older
5. Sex recorded as male or female
6. Urgent/emergent episodes (Admission Category Code = U in any records within an episode)

Note
*2018–2019 data onward.

Exclusions:

1. Records with an invalid health card number
2. Records with an invalid code for province issuing health card number
3. Records with an invalid admission date
4. Records with admission category of cadaveric donor or stillbirth (Admission Category Code = R or S)
5. Records with a status of dead on arrival (Discharge Disposition = 11, 71* for NACRS)
6. 2018–2019 data onward: Episodes with medical assistance in dying (MAID) (Discharge Disposition Code = 73)
7. AMI episodes with length of stay less than 24 hours and patients alive at end of episodes
8. Subsequent AMI episodes in the 11-month period (only the first AMI episode for a patient is included)

Note
*2018–2019 data onward.

Description:
Number of deaths from all causes occurring in hospital within 30 days of admission for AMI

Inclusions:

1. Discharges as deaths (Discharge Disposition Code = 07, 72*, 74*)
2. Admission to an acute care institution (Facility Type Code = 1)
3. (Discharge date on death record) − (Admission date on AMI record) less than or equal to 30 days

Note
*2018–2019 data onward.

Exclusions:

1. Records with an invalid discharge date
2. 2018–2019 data onward: Medical assistance in dying (MAID) (Discharge Disposition Code = 73)

A lower risk-adjusted mortality rate following AMI may be related to quality of care or other factors. It has been shown that the 30-day in-hospital mortality rate is highly correlated (r = 0.9) with total mortality (death in and out of hospital) following AMI.

Variations in 30-day in-hospital mortality rates may be due to jurisdictional and institutional differences in care practices, as well as to other factors that were not included in the adjustment.

Lower rates are desirable.

Health System Outputs: Appropriate and effective

Getting Better

Not applicable

Hosmer DW, Lemeshow S. Confidence Interval Estimates of an Index of Quality Performance Based on Logistic Regression Models. Stat Med 1995;(14):2161-2172.

Tu JV, Austin P, Naylor CD, Iron, K, Zhang H. Acute Myocardial Infarction Outcomes in Ontario (Methods Appendix). Cardiovascular Health & Services in Ontario: An ICES Atlas (Technical and Methods Appendices). Eds. Naylor CD and Slaughter PM. Toronto, ON; Institute for Clinical Evaluative Sciences:1999.

DAD, HMDB, NACRS

Type of Year:
Fiscal
First Available Year:
1998
Last Available Year:
2019

All provinces/territories

National, Province/Territory, Region

Every year

Web Tool:
Health Indicators e-Publication
URL: http://yourhealthsystem.cihi.ca/epub/?language=en

Beginning with the 2004 rates, AMI case selection criteria were revised to account for the fact that an increasing number of AMI patients are undergoing revascularization procedure (percutaneous coronary intervention or coronary artery bypass) at their index admission. In the case of revascularization procedure, AMI may not be coded as the most responsible diagnosis, and these cases were previously excluded from the indicator. In addition, exclusion criteria were revised and patients with a length of stay of less than three days and discharged alive are no longer excluded.

Prior to 2018–2019, indicator results by place of residence are based on 3 years of pooled data. Starting in 2018–2019, indicator results by place of residence are based on 1 year of data. Due to this change in reporting, trends over time should be interpreted with caution.

Not applicable

Please refer to the Updates section for information on trending.

Prior to 2018–2019, indicator results by place of residence are based on 3 years of pooled data. Starting in 2018–2019, indicator results by place of residence and place of service are both based on 1 year of data.

Indicator results by place of service are also available on our Health indicator reporting page (click Additional Acute Care Indicators).