I50.2 — Systolic (congestive) heart failure, unspecified

Clinical Definition

Systolic heart failure, also known as heart failure with reduced ejection fraction (HFrEF), is a clinical syndrome in which the heart's left ventricle loses its ability to contract effectively, resulting in a diminished ejection fraction (typically defined as an LVEF of 40% or less). This impaired contractile function leads to inadequate cardiac output, causing symptoms such as dyspnea, fatigue, exercise intolerance, and fluid retention. The condition may result from ischemic heart disease, dilated cardiomyopathy, valvular disease, hypertension, or other etiologies that damage or weaken the myocardium.

ICD-10-CM code I50.2 specifically captures systolic (congestive) heart failure that is unspecified as to whether it is acute, chronic, or acute on chronic. It serves as the parent code for the I50.2x subcategory and should be used when the clinical documentation does not further specify the acuity or temporal pattern of the systolic heart failure. Per AHA Coding Clinic guidance, this code maps to the clinical concept of HFrEF.

Patients with systolic heart failure commonly present with signs and symptoms of congestion (pulmonary rales, peripheral edema, jugular venous distension) and low cardiac output (fatigue, cool extremities, hypotension). Diagnosis is confirmed by echocardiography demonstrating reduced left ventricular ejection fraction. Guideline-directed medical therapy typically includes ACE inhibitors or ARNIs, beta-blockers, mineralocorticoid receptor antagonists, and SGLT2 inhibitors, along with diuretics for volume management.

When to Use I50.2

• ✓The patient has been diagnosed with systolic heart failure or HFrEF, but the documentation does not specify whether the condition is acute, chronic, or acute on chronic.
• ✓Echocardiography or other imaging confirms a reduced left ventricular ejection fraction (LVEF ≤ 40%) without further temporal qualification in the clinical record.
• ✓The provider documents 'systolic heart failure' or 'heart failure with reduced ejection fraction' without additional acuity descriptors.
• ✓Coding from a problem list or encounter summary where the clinician has not differentiated between acute and chronic presentations.
• ✓The patient carries a known diagnosis of systolic CHF and the visit documentation does not address the current acuity status.

Common Coding Mistakes

Related & Differential Codes

Documentation Requirements

• 1Type of heart failure: systolic (HFrEF), diastolic (HFpEF), or combined systolic and diastolic — documentation must clearly indicate systolic dysfunction to support I50.2x codes.
• 2Acuity: specify whether the heart failure is acute, chronic, or acute on chronic to allow assignment of the most specific subcategory code (I50.21, I50.22, or I50.23).
• 3Left ventricular ejection fraction (LVEF) from echocardiography or other imaging, with the date of the most recent measurement.
• 4NYHA functional classification (Class I-IV) to establish the severity of symptoms and functional limitation.
• 5Underlying etiology when known (e.g., ischemic cardiomyopathy, idiopathic dilated cardiomyopathy, valvular heart disease, hypertensive heart disease).
• 6Current signs and symptoms: document dyspnea, orthopnea, paroxysmal nocturnal dyspnea, peripheral edema, weight gain, fatigue, exercise intolerance, and any findings on physical examination.
• 7Treatment plan including guideline-directed medical therapy (ACEi/ARB/ARNI, beta-blocker, MRA, SGLT2 inhibitor), device therapy (ICD, CRT), and diuretic management.

Reimbursement & Billing Notes

ICD-10-CM code I50.2 is widely accepted by Medicare, Medicaid, and commercial payers for reimbursement of services related to systolic heart failure. However, payers and quality programs increasingly require the highest level of specificity available. When documentation supports a more specific subcategory code (I50.21, I50.22, or I50.23), that code should be used instead of the unspecified I50.2 to avoid potential claim denials or requests for additional information. Using the unspecified code when more detail is available may also trigger payer audits.

Heart failure is a major driver of risk adjustment under CMS-HCC (Hierarchical Condition Categories) models. Systolic heart failure codes in the I50.2x range map to HCC 85 (Heart Failure), which carries a significant risk adjustment factor. Accurate and specific coding of heart failure directly impacts RAF scores, capitated payment amounts, and quality measure reporting under programs such as MIPS, ACOs, and Medicare Advantage. Documentation must support the coded diagnosis at every encounter to ensure ongoing risk adjustment capture and compliance with retrospective audit requirements.

Frequently Asked Questions