ICD-10-CM 2027 diagnosis code
I47.9Paroxysmal tachycardia, unspecified
I47.9 is a valid, billable ICD-10-CM code for paroxysmal tachycardia, unspecified. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Looking up by condition? See ICD-10 code for Bouveret syndrome, ICD-10 code for Paroxysmal tachycardia, ICD-10 code for Hoffmann-Bouveret syndrome.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About I47.9
I47.9 is the ICD-10-CM diagnosis code for paroxysmal tachycardia, unspecified. It belongs to category I47 (paroxysmal tachycardia), block I30-I5A (other forms of heart disease) and chapter 9 (diseases of the circulatory system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within I47, choose I47.9 (unspecified) only when documentation doesn't support a more specific option: Re-entry ventricular arrhythmia (I47.0), supraventricular tachycardia (I47.1) and ventricular tachycardia (I47.2).
Code first tachycardia complicating: abortion or ectopic or molar pregnancy (O00-O07, O08.8) and obstetric surgery and procedures (O75.4).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 308 (Cardiac Arrhythmia and Conduction Disorders with MCC, relative weight 1.1806), DRG 309 (Cardiac Arrhythmia and Conduction Disorders with CC, relative weight 0.7316) and DRG 310 (Cardiac Arrhythmia and Conduction Disorders without CC/MCC, relative weight 0.568), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 427.2 (paroxysmal tachycardia, unspecified).
Coding notes
- Bouveret (-Hoffman) syndrome
Notes that apply from higher levels
Instructions written at a parent level also apply to I47.9.
› From I47 Paroxysmal tachycardia
Broader instructions also apply from Chapter 9: Diseases of the circulatory system.
Alphabetic index entries
5 entriesTerms in the official ICD-10-CM index that lead to I47.9.
Codes whose notes reference I47.9
- I21.A1Code first
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 05 · Diseases and Disorders of the Circulatory System
ICD-9-CM equivalent
Converter →- 427.2Paroxysmal tachycardia, unspecifiedexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about I47.9
Is I47.9 billable?
- Yes. I47.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I47.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I47.9 as a principal diagnosis.
Is I47.9 a CC or MCC?
- No. I47.9 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does I47.9 group to?
- I47.9 is used in the MS-DRG v44.0 logic for MS-DRG 308 (Cardiac Arrhythmia and Conduction Disorders with MCC), MS-DRG 309 (Cardiac Arrhythmia and Conduction Disorders with CC) and MS-DRG 310 (Cardiac Arrhythmia and Conduction Disorders without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for I47.9?
- The CMS General Equivalence Mappings map I47.9 to ICD-9-CM 427.2.