Documentation Guidelines for Cardiology

Specifying anatomical location and laterality required by ICD-10 is easier than you think. This detail reflects how physicians and clinicians communicate and to what they pay attention to – it is a matter of ensuring the information is captured in your documentation. In ICD-10-CM, there are three main categories of changes Definition Change; Terminology Differences; Increased Specificity. For cardiology, the focus is increased specificity and documenting the downstream effects of the patient’s condition.

Acute Myocardial Infarction (AMI)

When documenting AMI, include the following:

Timeframe An AMI is now considered “acute” for 4 weeks from the time of the incident, a revised timeframe from the current ICD-9 period of 8 weeks.
Episode of care ICD-10 does not capture the episode of care (e.g. initial, subsequent, sequelae).
Subsequent AMI ICD-10 allows coding of a new MI that occurs during the 4 weeks “acute period” of the original AMI.

(ICD-10 Code Examples: I21.02; I21.4; I22.1)


In ICD-10, hypertension is defined as essential (primary). The concept of “benign or malignant” as it relates to hypertension no longer exists. When documenting hypertension, include the following:

Type e.g. essential, secondary, etc.
Causal relationship e.g. Renal, pulmonary, etc.

(ICD-10 Code Examples: I10; I11.9; I15.0)

Congestive Heart Failure

The terminology used in ICD-10 exactly matches the types of CHF. If your document “decompensation” or “exacerbation,” the CHF type will be coded as “acute on chronic.” When documenting CHF, include the following:

Cause e.g. Acute, chronic
Severity e.g. Systolic, diastolic

(ICD-10 Code Examples: I50.23; I50.33; I50.43)


Underdosing is an important new concept and term in ICD-10. It allows you to identify when a patient is taking less of a medication than is prescribed. When documenting underdosing, include the following:

Intentional, Unintentional, Non-compliance Intentional, Unintentional, Non-compliance
Severity Why is the patient not taking the medication? (e.g. Financial hardship, age-related debility)

(ICD-10 Code Examples: Z91.120; T36.4x6A; T45.526D)

Atherosclerotic Heart Disease with Angina Pectoris

When documenting atherosclerotic heart disease with angina pectoris, include the following:

Cause Assumed to be atherosclerosis; notate if there is another cause
Stability e.g. Stable angina pectoris, unstable angina pectoris
Vessel Note which artery (if known) is involved and whether the artery is native or autologous
Graft involvement If appropriate, whether a bypass graft was involved in the angina pectoris diagnosis; also note the original location of the graft and whether it is autologous or biologic

(ICD-10 Code Examples: I25.110; I25.710)


When documenting cardiomyopathy, include the following, where appropriate:

Type e.g. Dilated/congestive, obstructive or nonobstructive hypertrophic, etc.
Location e.g. Endocarditis, right ventricle, etc.
Cause e.g. Congenital, alcohol, etc.

List cardiomyopathy is seen in other diseases such as gout, amyloidosis, etc.

(ICD-10 Code Examples: I42.0; I42.1; I42.3)

Heart Valve Disease

ICD-10 assumes heart valve diseases are rheumatic; if this is not the case, notate otherwise.

When documenting heart valve disease, including the following:

Cause e.g. Rheumatic or non-rheumatic
Type e.g. Prolapse, insufficiency, regurgitation, incompetence, stenosis, etc
Location e.g. Mitral valve, aortic valve, etc.

 (ICD-10 Code Examples: I06.2; I34.1)


When documenting arrhythmias, include the following:

Location e.g. Atrial, ventricular, supraventricular, etc.
Rhythm name e.g. Flutter, fibrillation, type 1 atrial flutter, long QT syndrome, sick sinus syndrome, etc.
Acuity e.g. Acute, chronic, etc.
Cause e.g., Hyperkalemia, hypertension, alcohol consumption, digoxin, amiodarone, verapamil HCl

(ICD-10 Code Examples: I48.2; I49.01)

Proper documentation is critical to justifying medical necessity and the selection of codes for billing. It tells the story of a patient visit by recording pertinent facts, findings, and observations. Payers will use this documentation to verify coding choices, site of service, medical necessity, appropriateness, and accurate reporting of furnished services. Each office note must tell a complete story and be able to stand alone.

Even small documentation errors can end up causing claims denials, and with all the voluminous claims filing that comes with cardiology billing and coding, it could be a good option for your practice to outsource your billing and coding. Through outsourcing, many cardiology practices are able to improve billing and coding efficiency so they’re able to spend more time focusing on offering patients quality patient care. Medical Billers and Coders (MBC) is a reputable medical billing and coding company that offers the highest quality service for clients across the country. To learn more about cardiology medical billing and coding contact us today at 888-357-3226/


Clinical Concepts for Cardiology