2025 ICD-10-CM Diagnosis Code I45.5

Other specified heart block

• I45.5 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
• The 2025 edition of ICD-10-CM I45.5 became effective on October 1, 2024.
• This is the American ICD-10-CM version of I45.5 – other international versions of ICD-10 I45.5 may differ.

Applicable To

• Sinoatrial block
• Sinoauricular block

Type 1 Excludes

• heart block NOS (I45.9)

The following code(s) above I45.5 contain annotation back-references

 that may be applicable to I45.5:

• I00-I99  Diseases of the circulatory system

Approximate Synonyms

• Sinoatrial block

Clinical Information

• A blockage of electrical conduction within the sinoatrial node resulting in the failure of impulse transmission from the sinoatrial node.
• A blockage of electrical conduction within the sinoatrial node resulting in the prolongation or failure (intermittent or complete) of impulse transmission from the sinoatrial node to the surrounding atrial tissue.
• Disturbance in the atrial activation that is caused by transient failure of impulse conduction from the sinoatrial node to the heart atria. It is characterized by a delayed in heartbeat and pauses between p waves in an electrocardiogram.

ICD-10-CM I45.5 is grouped within Diagnostic Related Group(s) (MS-DRG v42.0):

• 308 Cardiac arrhythmia and conduction disorders with mcc
• 309 Cardiac arrhythmia and conduction disorders with cc
• 310 Cardiac arrhythmia and conduction disorders without cc/mcc

Convert I45.5 to ICD-9-CMCode History

• 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
• 2017 (effective 10/1/2016): No change
• 2018 (effective 10/1/2017): No change
• 2019 (effective 10/1/2018): No change
• 2020 (effective 10/1/2019): No change
• 2021 (effective 10/1/2020): No change
• 2022 (effective 10/1/2021): No change
• 2023 (effective 10/1/2022): No change
• 2024 (effective 10/1/2023): No change
• 2025 (effective 10/1/2024): No change

Diagnosis Index entries containing back-references to I45.5:

• Arborization block I45.5 (heart)
• Arrest, arrested
  • sinus I45.5
• Block, blocked
  • heartI45.9
    • specified type NEC I45.5
  • arborization I45.5 (heart)
  • nodal I45.5
  • sinoatrial I45.5
  • sinoauricular I45.5
• Sinus – see also Fistula
  • arrest I45.5
  • pause I45.5
• Standstill
  • auricular I45.5
  • sinoatrial I45.5