Acute Myocardial Infarction (AMI)

Set Measures

Set Measure ID	Measure Short Name
AMI-1	Aspirin at Arrival
AMI-2	Aspirin Prescribed at Discharge
AMI-3	ACEI or ARB for LVSD
AMI-4	Adult Smoking Cessation Advice/Counseling
AMI-5	Beta-Blocker Prescribed at Discharge
AMI-6	Beta-Blocker at Arrival
AMI-7	Median Time to Fibrinolysis
AMI-7a	Fibrinolytic Therapy Received Within 30 Minutes of Hospital Arrival
AMI-8	Median Time to Primary PCI
AMI-8a	Primary PCI Received Within 90 Minutes of Hospital Arrival
AMI-9	Inpatient Mortality
AMI-T1a	LDL Cholesterol Assessment (Optional Test Measure)
AMI-T2	Lipid-Lowering Therapy at Discharge (Optional Test Measure)

General Data Elements

Element Name	Collected For
Birthdate	All Records,
Discharge Date	All Records, (used in algorithm for AMI-1, AMI-6, PN-1, PN-3a, PN-3b, PN-5, PN-5b, PN-5c, PN-6, PN-6a, PN-6b, PN-7, PR-2, SCIP-Inf-4, SCIP-VTE-1, SCIP-VTE-2)
Discharge Status	All Records, (used in algorithm for AMI-1, AMI-2, AMI-3, AMI-4, AMI-5, AMI-6, AMI-9, AMI-T1a and AMI-T2 [CMS Optional Test Measures], CAC-3 [Joint Commission Test Measure], All HF Measures, All PN Measures, PR-2)
First Name	All Records, CMS Only,
Hispanic Ethnicity	All Records, CMS Only,
Hospital Patient Identifier	All Records, CMS Only, NOTE: Refer to the Hospital Clinical Data XML File Layout in the Transmission section of this manual.
Last Name	All Records, CMS Only,
Patient HIC#	All Records, CMS Only, Collected by CMS for patients with a Payment Source - Medicare who have a standard HIC number.
Physician 1	All Records, Optional for All Records, (CMS Optional Element)
Physician 2	All Records, Optional for All Records, (CMS Optional Element)
Point of Origin for Admission or Visit	All Records, (used in algorithm for AMI-1, AMI-6, AMI-7, AMI-7a, AMI-8, AMI-8a, AMI-9, PN-1, PN-3a, PN-5, PN-5b, PN-5c, PN-6, PN-6a, PN-6b
Postal Code	All Records, CMS Only,
Race	All Records, CMS Only,

Algorithm Output Data Elements

Element Name	Collected For
Measure Category Assignment	Joint Commission Only, Calculation, Transmission, Hospital Clinical Data File

Measure Set Specific Data Elements

Element Name	Collected For
ACEI Prescribed at Discharge	AMI-3,
ARB Prescribed at Discharge	AMI-3,
Adult Smoking Counseling	AMI-4,
Adult Smoking History	AMI-4,
Arrival Date	AMI-1, AMI-6, AMI-7a, AMI-8, AMI-8a,
Arrival Time	AMI-7, AMI-7a, AMI-8, AMI-8a,
Aspirin Prescribed at Discharge	AMI-2,
Aspirin Received Within 24 Hours Before or After Hospital Arrival	AMI-1,
Beta-Blocker Prescribed at Discharge	AMI-5,
Beta-Blocker Received Within 24 Hours After Hospital Arrival	AMI-6,
Comfort Measures Only	AMI-1, AMI-2, AMI-3, AMI-4, AMI-5, AMI-6, AMI-7, AMI-7a, AMI-8, AMI-8a, AMI-9, AMI-T1a, AMI-T2,
Contraindication to Aspirin at Discharge	AMI-2,
Contraindication to Aspirin on Arrival	AMI-1,
Contraindication to Beta-Blocker at Discharge	AMI-5,
Contraindication to Beta-Blocker on Arrival	AMI-6,
Contraindication to Both ACEI and ARB at Discharge	AMI-3,
Fibrinolytic Administration	AMI-7, AMI-7a, AMI-8, AMI-8a,
Fibrinolytic Administration Date	AMI-7, AMI-7a,
Fibrinolytic Administration Time	AMI-7, AMI-7a,
First In-Hospital LDL-Cholesterol Qualitative Description	AMI-T2,
First In-Hospital LDL-Cholesterol Value	AMI-T2,
First PCI Date	AMI-8, AMI-8a,
First PCI Time	AMI-8, AMI-8a,
In-Hospital LDL-Cholesterol Test	AMI-T1a, AMI-T2,
Initial ECG Interpretation	AMI-7, AMI-7a, AMI-8, AMI-8a,
LVSD	AMI-3,
Lipid-Lowering Agent Prescribed at Discharge	AMI-T2,
Non-Primary PCI	AMI-8, AMI-8a,
Plan for LDL-Cholesterol Test	AMI-T1a,
Pre-Arrival LDL-Cholesterol Qualitative Description	AMI-T1a, AMI-T2,
Pre-Arrival LDL-Cholesterol Test	AMI-T1a, AMI-T2,
Pre-Arrival LDL-Cholesterol Value	AMI-T1a, AMI-T2,
Pre-Arrival Lipid-Lowering Agent	AMI-T1a,
Reason for Delay in Fibrinolytic Therapy	AMI-7, AMI-7a,
Reason for Delay in PCI	AMI-8, AMI-8a,
Reason for No LDL-Cholesterol Testing	AMI-T1a,
Reason for No Lipid-Lowering Therapy	AMI-T2,
Transfer From Another ED	AMI-1, AMI-6, AMI-7, AMI-7a, AMI-8, AMI-8a,

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Related Materials

	Document Name
	a. Table of Contents
	a1. Introduction to the manual
	a2. Acknowledgement and Conditions of Use
	a3. Using the Specifications Manual for National Hospital Inpatient Quality Measures
	b. Introduction to the Data Dictionary and lists of all data elements
	d. Missing and Invalid Data Chapter
	e. Population and Sampling Specifications
	j. National Hospital Quality Measure Data Transmission
	z. Appendix A - ICD-9-CM Code Tables
	z. Appendix C - Medication Tables
	z. Appendix D - Glossary of Terms
	z. Appendix E - Measure Information Form and Flowchart Definitions
	z. Appendix G - Resources
	z. Appendix H - Miscellaneous Tables

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Acute Myocardial Infarction (AMI) Initial Patient Population

The population of the AMI measure set is identified using 4 data elements:

• ICD-9-CM Principal Diagnosis Code
• Admission Date
• Birthdate
• Discharge Date

Patients admitted to the hospital for inpatient acute care with an ICD-9-CM Principal Diagnosis Code for AMI as defined in Appendix A Table 1.1, a Patient Age (Admission Date – Birthdate) >= 18 years and a Length of Stay (Discharge Date - Admission Date) <= 120 days are included in the AMI Initial Patient Population and are eligible to be sampled.

• View the AMI Initial Population Algorithm

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Sample Size Requirements

Hospitals that choose to sample have the option of sampling quarterly or sampling monthly. A hospital may choose to use a larger sample size than is required. Hospitals whose Initial Patient Population size is less than the minimum number of cases per quarter for the measure set cannot sample.

Regardless of the option used, hospital samples must be monitored to ensure that sampling procedures consistently produce statistically valid and useful data. Because the sample for a measure set will rarely be equal to the effective sample due to exclusions and contraindications, hospitals selecting sample cases MUST submit AT LEAST the minimum required sample size.

The following sample size tables for each option automatically build in the number of cases needed to obtain the required sample sizes. For information concerning how to perform sampling, refer to the Population and Sampling Specifications section in this manual.

Quarterly Sampling

Hospitals performing quarterly sampling for AMI must ensure that its Initial Patient Population and effective sample size meet the following conditions:

• The effective quarterly sample size for a measure set is at least 35 cases per quarter; and
• The required sample size is at least 20% of the Initial Patient Population for the quarter.

Quarterly Sample Size
Based on Initial Patient Population for the AMI Measure Set

Hospital's Measures
Average Quarterly Initial Patient Population “N”	Minimum Required Sample Size “n”
> 1550	311
391 - 1550	20% of the Initial Patient Population
< 78	No sampling; 100% of the Initial Patient Population is required

Monthly Sampling

Hospitals performing monthly sampling for AMI must ensure that its Initial Patient Population and effective sample size meet the following conditions:

• The effective monthly sample size for AMI is at least 12 cases per month; and
• The required sample size is at least 20% of the Initial Patient Population for the month.

Monthly Sample Size
Based on Initial Patient Population for the AMI Measure Set

Hospital's Measures
Average Monthly Initial Patient Population “N”	Minimum Required Sample Size “n”
> 515	104
131 – 515	20% of the Initial Patient Population
26 – 130	26
< 26	No sampling; 100% of the Initial Patient Population is required

Sample Size Examples

• Quarterly sampling:
  • A hospital’s AMI Initial Patient Population size is 100 patients during the fourth quarter. The required sample size is seen to be a minimum of 78 AMI patients for this quarter.
  • A hospital’s AMI Initial Patient Population size is 392 patients during the third quarter. The required sample size is 20% of the patient population or 79 cases for the quarter (twenty percent of 392 equals 78.4 rounded to the next highest whole number = 79).
• Monthly sampling
  • A hospital’s AMI Initial Patient Population size is 516 patients during March. The required sample size is 104 cases from the patient population.
  • A hospital’s AMI Initial Patient Population size is 502 patients during July. The required sample size is 20% of the patient population or 101 cases for the month (twenty percent of 502 equals 100.4 rounded to the next highest whole number = 101).