R00.0 Tachycardia, unspecified

The ICD-10-CM code for Tachycardia, unspecified is R00.0 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)

Section

R00-R09: Symptoms and signs involving the circulatory and respiratory systems (R00-R09)

Category R00

6 codes (5 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to R00.0:

• Tachycardia
• Fast pulse
• Tachycardia › sinoauricular NOS
• Sinus › tachycardia
• Rapid › heart (beat)
• Pulse › fast
• Heart beat › rapid
• Pulse › rapid

Inclusion Terms

• Rapid heart beat
• Sinoauricular tachycardia NOS
• Sinus [sinusal] tachycardia NOS

U.S. Hospital Utilization

• An estimated 645,540 U.S. inpatient stays in 2023 included R00.0 among the documented diagnoses.
• 3,770 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Signs and symptoms acceptable if no confirmed diagnosis

4. Signs and symptoms Codes that describe symptoms and signs, as opposed to diagnoses, are acceptable for reporting purposes when a related definitive diagnosis has not been established (confirmed) by the provider. Chapter 18 of ICD-10-CM, Symptoms, Signs, and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (codes R00.0 - R99) contains many, but not all, codes for symptoms. See Section I.B.18. Use of Signs/Symptom/Unspecified Codes

Chapter 18 scope; symptoms pointing to specific dx classified elsewhere

18. Chapter 18: Symptoms, signs, and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99) Chapter 18 includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded. Signs and symptoms that point to a specific diagnosis have been assigned to a category in other chapters of the classification.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)