Summary & Overview

HCPCS G9804: Post-AMI Beta-Blocker Treatment Gap

HCPCS Level II code G9804 documents a gap in post-discharge pharmacologic secondary prevention: the patient was not prescribed at least a 135-day course of beta-blocker therapy within a 180-day measurement window after an acute myocardial infarction (AMI). Nationally, this code is used in quality reporting and claims to flag incomplete beta-blocker coverage after AMI, an area linked to secondary prevention and readmission risk. The code matters because it captures lapses in guideline-concordant pharmacotherapy that payers and quality programs monitor.

The analysis covers major national payers including Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the code's clinical intent, the service context (post-discharge medication management after AMI), typical sites of service, and how the code fits into quality measurement. The publication summarizes common modifiers and notes when input fields are not provided.

This briefing will help clinicians, billing teams, and policy stakeholders understand the purpose of G9804, where it is applied in the care pathway, and what documentation and measurement implications are associated with recording a post-AMI beta-blocker treatment gap.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareG9804HCPCS Level IIpost-discharge carebeta-blockersacute myocardial infarctionquality measuremedication managementsecondary prevention

Billing Code Overview

HCPCS Level II code G9804 indicates that a patient was not prescribed at least a 135-day treatment within the 180-day measurement interval with beta-blockers post-discharge for AMI. This measure reflects medication management and follow-up after an acute myocardial infarction.

Service type: Post-discharge medication management and quality measurement related to secondary prevention after acute myocardial infarction
Typical site of service: Hospital inpatient discharge and outpatient follow-up care settings

Clinical & Coding Specifications

Clinical Context

A typical patient is a 62-year-old male admitted to the hospital with an acute myocardial infarction (AMI) who is discharged after stabilization. During the hospitalization the patient underwent cardiac monitoring and medical management but had documented contraindications to beta-blocker therapy (for example, persistent bradycardia or symptomatic hypotension) or beta-blocker therapy was not started. The measure represented by G9804 captures that the patient was not prescribed at least a 135-day supply of beta-blocker therapy within the 180-day post-discharge measurement interval.

Clinical workflow: On discharge the inpatient team documents medication reconciliation and the discharge medication list. Outpatient cardiology or primary care follow-up within 7–30 days reviews secondary prevention medications. Pharmacy fills and outpatient prescription records are reviewed to determine whether at least a 135-day supply of a beta-blocker was prescribed within 180 days after discharge. If a patient has a documented clinical contraindication to beta-blockers, this is noted in the chart and the measure is coded accordingly. Typical sites of service include inpatient hospital (acute care) for the index AMI admission and outpatient offices or clinics (cardiology, primary care) for follow-up and medication management.

Coding Specifications

Modifier	Description	When to Use
`22`	Increased procedural services	Use when atypical work or increased complexity related to discharge planning or medication reconciliation requires substantial additional physician work.
`23`	Unusual anesthesia	Rarely applicable; only used if anesthesia was provided and was unusual during any concomitant procedure tied to the admission.
`52`	Reduced services	Use when a related service was partially reduced or not completed (e.g., partial outpatient medication visit).
`53`	Discontinued procedure	Use if a planned procedure related to AMI care was started but discontinued for clinical reasons.
`54`	Surgical care only	Use when only the surgical component of a related procedure was performed; rarely used for medical discharge coding.
`55`	Postoperative management only	Use when only postoperative follow-up was billed by another provider managing medication changes post-discharge.
`56`	Preoperative management only	Use when another provider billed preoperative management during the index admission.
`62`	Two surgeons	Use only if two surgeons were required for a related surgical intervention during the admission.
`AS`	Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery	Use when an advanced practice provider assisted in a procedure during the admission.
`CO`	Temporary public health emergency exemption	Use when the claim relates to a designated public health emergency exemption (payor-specific).
`CQ`	Service furnished by a rehabilitation agency (in lieu of home health)	Use if a rehabilitation agency provided services relevant to post-AMI care.
`FX`	Hardware failure	Use if a procedure required revision due to hardware failure during follow-up care.
`FY`	Item replacement from warranty	Use if equipment replacement under warranty was provided during follow-up care.
`QK`	Medical direction of two, three, or four concurrent anesthesia procedures	Use if anesthesia direction was billed for concurrent cases.
`QX`	CRNA service with medical direction	Use when a CRNA furnished anesthesia under medical direction during an operative procedure associated with the admission.

Taxonomy Code	Specialty	Notes
`207R00000X`	Cardiology	Inpatient and outpatient cardiologists manage secondary prevention medications post-AMI.
`207L00000X`	Interventional Cardiology	Often involved if the AMI required PCI; participates in discharge medication decisions.
`207Q00000X`	Family Medicine	Primary care physicians coordinate outpatient medication management and follow-up.
`208D00000X`	Internal Medicine	Hospitalists and internists manage inpatient care and discharge prescriptions.
`363L00000X`	Nurse Practitioner	Advanced practice providers commonly manage follow-up medication reconciliation and prescriptions.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`I21.9`	Acute myocardial infarction, unspecified	Represents AMI as the index event for which beta-blocker therapy is a standard component of secondary prevention.
`I21.3`	ST elevation (STEMI) myocardial infarction of other sites of posterior wall	A specific AMI subtype where beta-blockers are commonly indicated post-discharge.
`I21.4`	Non-ST elevation (NSTEMI) myocardial infarction	NSTEMI is an AMI subtype; beta-blocker prescribing is evaluated during the post-discharge interval.
`I25.10`	Atherosclerotic heart disease of native coronary artery without angina pectoris	Chronic coronary disease status relevant to ongoing beta-blocker therapy decisions.
`I50.9`	Heart failure, unspecified	Heart failure may modify beta-blocker choice or dosing and is relevant when assessing contraindications or treatment plans.
`Z79.899`	Other long term (current) drug therapy	Used to document ongoing medication therapy; relevant when assessing prior beta-blocker use.
`R00.0`	Tachycardia, unspecified	Baseline arrhythmias or rate issues that influence beta-blocker initiation or avoidance.
`R00.1`	Bradycardia, unspecified	Bradycardia is a potential contraindication to beta-blocker therapy and explains omission of prescriptions.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`99238`	Hospital discharge day management; 30 minutes or less	Used by the discharging physician to document discharge and the medication reconciliation that would include beta-blocker prescriptions.
`99496`	Transitional care management services with high complexity medical decision making (7–14 days)	Used for early post-discharge follow-up that includes medication management and reconciliation relevant to beta-blocker prescribing.
`93000`	Electrocardiogram, routine ECG with at least 12 leads; with interpretation and report	Performed during index admission and sometimes at follow-up to assess cardiac status influencing beta-blocker use.
`92928`	Percutaneous coronary intervention (PCI) with stent; single vessel	Commonly performed during AMI admission; interventional procedures influence secondary prevention medication plans.
`99490`	Chronic care management services, at least 20 minutes of clinical staff time directed by a physician or other qualified health care professional, per calendar month	Ongoing outpatient management that may include ensuring continuity of beta-blocker therapy within the measurement interval.