Cardiology ICD-10-CM codes

Coronary artery disease without angina defaults to I25.10; the I25.11x combination codes apply when angina pectoris is documented, and per the guidelines the CAD-angina link is presumed. Old MI (I25.2) is coded once the acute window has passed, and ischemic cardiomyopathy is I25.5. Follow the hypertension combination rules: heart failure with hypertension takes I11.0 first, then the specific I50 code, and I13.0 when CKD is also present.

Atrial fibrillation should be coded to its documented pattern, not I48.91: paroxysmal (I48.0), persistent (I48.11), longstanding persistent (I48.19), chronic unspecified (I48.20), or permanent (I48.21). Heart failure similarly needs type and acuity: I50.22 and I50.32 for chronic systolic and diastolic failure, I50.23 and I50.33 for acute on chronic. These distinctions change both risk adjustment and payer edits on device and monitoring claims.

Symptom codes (R07.9 chest pain, R00.2 palpitations, R55 syncope, R06.02 shortness of breath) are appropriate as first-listed diagnoses for diagnostic workups when no cause has been established; once a definitive diagnosis is made, drop the symptom code. Status codes matter for every follow-up: Z95.0 pacemaker, Z95.1 CABG, Z95.2 prosthetic valve, Z95.5 coronary stent, plus Z79.01 and Z79.02 for the anticoagulant and antiplatelet monitoring that accompanies AFib and stent management.