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ICD10BillableValid for clinical use

ICD-10 Code G45.9: Transient cerebral ischemic attack, unspecified

G45.9 is a billable ICD-10 diagnosis code used to classify Transient cerebral ischemic attack, unspecified in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).

What is this code?

ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).

When is it used?

  • May be used when a clinician documents transient cerebral ischemic attack, unspecified in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code can be used as a clinically usable diagnosis entry in standardized coding workflows.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.

Code hierarchy

chapter
6Diseases of the nervous system (G00-G99)
block
G40-G47Episodic and paroxysmal disorders
category
G45Transient cerebral ischemic attacks and related syndromes
currentG45

Official coding notes

Inclusion terms
  • Spasm of cerebral artery
  • TIA
  • Transient cerebral ischemia NOS

Where you may see this code

You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.

Related specialists

NeurologistGeneral Physician

Coverage-related procedures and services

CPT 93228high
EXTERNAL MOBILE CARDIOVASCULAR TELEMETRY WITH ELECTROCARDIOGRAPHIC RECORDING, CONCURRENT COMPUTERIZED REAL TIME DATA ANALYSIS AND GREATER THAN 24 HOURS OF ACCESSIBLE ECG DATA STORAGE (RETRIEVABLE WITH QUERY) WITH ECG TRIGGERED AND PATIENT SELECTED EVENTS TRANSMITTED TO A REMOTE ATTENDED SURVEILLANCE CENTER FOR UP TO 30 DAYS; REVIEW AND INTERPRETATION WITH REPORT BY A PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL
Source: CMS coverage guidance
CPT 93229high
EXTERNAL MOBILE CARDIOVASCULAR TELEMETRY WITH ELECTROCARDIOGRAPHIC RECORDING, CONCURRENT COMPUTERIZED REAL TIME DATA ANALYSIS AND GREATER THAN 24 HOURS OF ACCESSIBLE ECG DATA STORAGE (RETRIEVABLE WITH QUERY) WITH ECG TRIGGERED AND PATIENT SELECTED EVENTS TRANSMITTED TO A REMOTE ATTENDED SURVEILLANCE CENTER FOR UP TO 30 DAYS; TECHNICAL SUPPORT FOR CONNECTION AND PATIENT INSTRUCTIONS FOR USE, ATTENDED SURVEILLANCE, ANALYSIS AND TRANSMISSION OF DAILY AND EMERGENT DATA REPORTS AS PRESCRIBED BY A PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL
Source: CMS coverage guidance
CPT 93268high
EXTERNAL PATIENT AND, WHEN PERFORMED, AUTO ACTIVATED ELECTROCARDIOGRAPHIC RHYTHM DERIVED EVENT RECORDING WITH SYMPTOM-RELATED MEMORY LOOP WITH REMOTE DOWNLOAD CAPABILITY UP TO 30 DAYS, 24-HOUR ATTENDED MONITORING; INCLUDES TRANSMISSION, REVIEW AND INTERPRETATION BY A PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL
Source: CMS coverage guidance
CPT 93270high
EXTERNAL PATIENT AND, WHEN PERFORMED, AUTO ACTIVATED ELECTROCARDIOGRAPHIC RHYTHM DERIVED EVENT RECORDING WITH SYMPTOM-RELATED MEMORY LOOP WITH REMOTE DOWNLOAD CAPABILITY UP TO 30 DAYS, 24-HOUR ATTENDED MONITORING; RECORDING (INCLUDES CONNECTION, RECORDING, AND DISCONNECTION)
Source: CMS coverage guidance
CPT 93272high
EXTERNAL PATIENT AND, WHEN PERFORMED, AUTO ACTIVATED ELECTROCARDIOGRAPHIC RHYTHM DERIVED EVENT RECORDING WITH SYMPTOM-RELATED MEMORY LOOP WITH REMOTE DOWNLOAD CAPABILITY UP TO 30 DAYS, 24-HOUR ATTENDED MONITORING; REVIEW AND INTERPRETATION BY A PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL
Source: CMS coverage guidance
CPT 93271high
EXTERNAL PATIENT AND, WHEN PERFORMED, AUTO ACTIVATED ELECTROCARDIOGRAPHIC RHYTHM DERIVED EVENT RECORDING WITH SYMPTOM-RELATED MEMORY LOOP WITH REMOTE DOWNLOAD CAPABILITY UP TO 30 DAYS, 24-HOUR ATTENDED MONITORING; TRANSMISSION AND ANALYSIS
Source: CMS coverage guidance

Coding guidelines

Compatibility

Legacy and official ICD code match exactly.
Legacy codes
G45.9

Common synonyms

Transient cerebral ischemic attack, unspecifiedTransient cerebral ischemic attack

Frequently asked questions

Code details

CodeG45.9
SystemICD10
Display nameTransient cerebral ischemic attack, unspecified
ChapterDiseases of the nervous system (G00-G99)
BlockEpisodic and paroxysmal disorders

Flags

BillableYes
Valid clinical useYes

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

Index terms

Matched terms
Angiospasm(peripheral) (traumatic) (vessel)Attack, attacksClaudication(intermittent)Disease, diseasedIschemia, ischemicIschemia, ischemicSpasm(s), spastic, spasticitySpasm(s), spastic, spasticity

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.