In-hospital (same hospital) mortality rate within 30 days of hospital admission for acute myocardial infarction (AMI).
Percent of patients admitted (alternative: percent of admission) for AMI who died in the hospital within 30 days of admission.
(including justification, strengths and limits)
Mortality of patients with AMI represents a significant outcome potentially related to quality of care. This rate-based indicator identifies an undesirable outcome of care. High rates over time warrant investigation into the quality of care provided.
Strong rationale, death is an outcome that needs to be avoided.
Literature demonstrates clear relationships between clinical processes and procedures and mortality, i.e. mortality is a proxy for good clinical practice. This indicator can to some extent be used to monitor the effect of quality improvement actions.
Rating is strongly affected by risk adjustment procedure, time frame and whether or not deaths after discharge are included. Overall the reliability is dependent on the magnitude of the patient population (unit level) and the quality of coding in administrative databases).
Such sub-indicators (mortality rate for patient not transferred, for patients transferred from/to another hospital) might provide additional insights and be included in the reports. It would be also very useful information how many percent of patients belong to these sub-samples. It might be also analysed if transfers were from or to: home / nursing home / rehabilitation hospital / acute care hospital / other.
For analysis of indicators and better understanding variations, it is suggested to measure also mortality rate within 24h or 48h and length of stay in hospital (for the initial stay, if readmitted).
Previous PATH experience
In PATH-pilot and PATH-II, patients both transferred from another hospital or to another hospital were excluded from both the numerator and denominator. This exclusion criterion has significantly been discussed while looking at the result as part of the proper treatment for AMI might include temporary transfer to another facility for appropriate invasive examination/treatment if the technology is not available in the hospital where the patient was initially admitted.
In PATH-II, it was initially proposed to adjust for both age and sex. However, sex did not come out as a significant variable to predict mortality. And the predictive value of the logarithmic model solely based on age was extremely low. Hence, based on PATH-II experience, it was agreed that risk-adjustment with such limited information on risk factors does not have much sense and that it is preferable to present results stratified by age and sex categories.
International comparison on 30-days mortality rate after admission for AMI (rate calculated at the country level)
International comparison on 30-days mortality rate after admission for AMI (rate calculated at the hospital level) (boxplot: min, 1st quartile, 3rd quartile, max)
International comparison on 30-days mortality rate after admission for AMI per age category (rate calculated at the country level)
Retrospective data collection. Administrative databases (e.g. discharge abstracts).
Compute the indicator on three full years to identify potential trends (2006, 2007, 2008) or the three last available years.
It is necessary to have a unique patient identifier in order to be able to trace case fatalities after the patient has been discharged and readmitted to the same hospital. This should be discussed among PATH participating hospitals in the country before implementation of the indicator. Any local adaptation of the definition should be made very explicit and agreed among all hospitals. The PATH Coordinator in the Country should inform the International Secretariat.
Alternative definition (if no unique patient identifier): Admission based indicator (see definition above in italic and underlined): in-hospital mortality during initial episode of care.
Complementary optional indicator (if hospital database is linked with death registry): 30-days mortality (within hospital or in any other care setting or at home).
Patient level data that should be sent to the PATH Coordinator in the Country are described at appendix 1.
Very low rates may indicate early discharges or transfers rather than high quality of care and lack of registration of deaths in emergency room settings.
International studies report a general decreasing trend in mortality due to coronary heart diseases. Data from different sources report variations in in-hospital mortality from 4-7% (1-3). In-hospital mortality rates are usually higher in patients without documented ischemic symptoms at admission (4).
The presence of extra cardiac vascular disease and overweight/obese are risk factors for poor outcome in patients with an acute myocardial infarction (5). This also applies to diabetes which increases in-hospital mortality significantly when patients with no diabetes are compared with diabetics, respectively diabetics with end-organ damage (5.7%, 7.8%, 13.5% mortality) (3).
There are different risk-scores and models available to predict mortality and guide the clinical decision-making process when the patient is admitted to the hospital after acute myocardial infarction (6-8). One-year mortality observed by different sources often exceeds 10% (5, 9).
Reasons for variations in in-hospital mortality are related to differences in case-ascertainment and case-mix, but to a large extent may reflect local practices: hospitals may attract different types of patients or differ in procedures for the admission and discharge of patients.
For analysis of indicators and better understanding variations, it is suggested to define, for each patient, whether he/she was transferred from another hospital, to another hospital, to another care setting (rehabilitation or nursing home) and length of stay in hospital (for the initial stay, if readmitted). Such sub-indicators (mortality rate for patient not transferred, for patients transferred from another acute care hospital, transferred to another hospital, transferred to a rehabilitation or mortality rate within 24h or 48 h) might provide additional insights and be included in the reports.
The definition of this indicator is mapped on OECD health care quality indicators. Hence, the same measure at the national level is available as a reference point for some countries.
Peer groups: Before implementation of the indicator, the participating hospitals in the country could agree on some specific criteria for comparing results based on available technology in the hospital or other structural factors.
Key specific quality issues which should be addressed e.g. by medical record reviews in units with high mortality rates (e.g. 2 standard deviations above peer group average) (10):
Further information on the management and guidelines of acute myocardial events: http://www.americanheart.org
McNamara RL, Wang Y, Herrin J, Curtis JP, Bradley EH, Magid DJ, et al. Effect of Door-to-Balloon Time on Mortality in Patients With ST-Segment Elevation Myocardial Infarction. Journal of the American College of Cardiology. 2006;47(11):2180-6.
Chew DP, Amerena J, Coverdale S, Rankin J, Astley C, Brieger D. Current management of acute coronary syndromes in Australia: observations from the acute coronary syndromes prospective audit. Internal Medicine Journal. 2007:(OnlineEarly Articles).
Verein Outcome. Results of outcome measurements in hospitals in Switzerland. Unpublished data. www.vereinoutcome.ch
Schelbert EB, Rumsfeld JS, Krumholz HM, Canto JG, Magid DJ, Masoudi FA, et al. Ischaemic Symptoms, Quality of Care, and Mortality during Myocardial Infarction. Heart. 2007 July 16, 2007:hrt.2006.111674.
Anderson JL, Adams CD, Antman EM, Bridges CR, Califf RM, Casey DE, Jr., et al. ACC/AHA 2007 Guidelines for the Management of Patients With Unstable Angina/Non ST-Elevation Myocardial Infarction: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines for the Management of Patients With Unstable Angina/Non ST-Elevation Myocardial Infarction) Developed in Collaboration with the American College of Emergency Physicians, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons Endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation and the Society for Academic Emergency Medicine. J Am Coll Cardiol. 2007 August 14, 2007;50(7):e1-157.
Antman EM, Cohen M, Bernink PJ, McCabe CH, Horacek T, Papuchis G, et al. The TIMI risk score for unstable angina/non-ST elevation MI: A method for prognostication and therapeutic decision making. Jama. 2000 Aug 16;284(7):835-42.
Boersma E, Pieper KS, Steyerberg EW, Wilcox RG, Chang WC, Lee KL, et al. Predictors of outcome in patients with acute coronary syndromes without persistent ST-segment elevation. Results from an international trial of 9461 patients. The PURSUIT Investigators. Circulation. 2000 Jun 6;101(22):2557-67.
Granger CB, Goldberg RJ, Dabbous O, Pieper KS, Eagle KA, Cannon CP, et al. Predictors of hospital mortality in the global registry of acute coronary events. Arch Intern Med. 2003 Oct 27;163(19):2345-53.
Schiele F, Meneveau N, Seronde MF, Caulfield F, Fouche R, Lassabe G, et al. Compliance with guidelines and 1-year mortality in patients with acute myocardial infarction: a prospective study. Eur Heart J. 2005 May 1, 2005;26(9):873-80.
Peterson ED, Shah BR et al. Trends in the quality of care for patients with acute myocardial infarction in the national registry of myocardial infarction from 1990 to 2006 . Amer Heart J. 2008; 156(6): 1045-55.
Lewis WR, Peterson ED et al. An organizes approach to improvement in guideline adherence for acute myocardial infarction. Arch Int Med 2008; 168(16): 1813-19.
http://www.OECD.org (Health at a glance, technical manuals).
Data to be reported to the coordinator for calculation of the core and complementary indicators
This form is to be used as a stepping stone to define national reporting forms for hospitals that can then be created e.g. into xls sheet or database tool.
At the patient level (one record per patient)
Data from the hospital central database or national database
Italics underlined for the minimum data for core indicator
* for risk-adjustment or for sub-indicators
**to compare process of care and initiate discussion on differences of practice