ICD-10 Code for Arrhythmia
Also indexed as (auricle)(cardiac)(juvenile)(nodal)(reflex)(supraventricular)(transitory)(ventricle)
The ICD-10-CM code for arrhythmia is I49.9 — Cardiac arrhythmia, unspecified. This is the code the Alphabetic Index gives for arrhythmia with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
I49.9 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.
Which arrhythmia code should you use?
The Alphabetic Index lists 12 codes under Arrhythmia. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
By type
| block | I45.9 | Conduction disorder, unspecified | |
| extrasystolic | I49.49 | Other premature depolarization | |
| psychogenic | F45.8 | Other somatoform disorders | |
| sinus | I49.89 | Other specified cardiac arrhythmias not elsewhere classified | |
| specified NEC | I49.89 | Other specified cardiac arrhythmias not elsewhere classified | |
| vagal | R55 | Syncope and collapse | |
| ventricular re-entry | I47.0 | Re-entry ventricular arrhythmia |
Arrhythmia newborn
| bradycardia | P29.12 | Neonatal bradycardia | |
| occurring before birth | P03.819 | Newborn affected by abnormality in fetal (intrauterine) heart rate or rhythm, unspecified as to time of onset | |
| tachycardia | P29.11 | Neonatal tachycardia | |
| occurring before birth › before onset of labor | P03.810 | Newborn affected by abnormality in fetal (intrauterine) heart rate or rhythm before the onset of labor | |
| occurring before birth › during labor | P03.811 | Newborn affected by abnormality in fetal (intrauterine) heart rate or rhythm during labor |
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources