I45.9 vs R55
I45.9 (Conduction disorder, unspecified) compared with R55 (Syncope and collapse), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. R55 carries an Excludes1 note covering I45.9: “Stokes-Adams attack (I45.9)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| I45.9Conduction disorder, unspecified | R55Syncope and collapse | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | I00-I99 — Diseases of the Circulatory System (I00-I99) | R00-R99 — Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) |
| Definition | Conduction disorder, unspecified is a billable ICD-10-CM diagnosis code (I45.9). | Syncope and collapse is a billable ICD-10-CM diagnosis code (R55). |
| Includes | Heart block NOS Stokes-Adams syndrome | Blackout Fainting Vasovagal attack |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources