ICD-9-CM procedure code (retired)
37.21 — Right heart cardiac catheterization
ICD-9-CM was replaced by ICD-10 on October 1, 2015. These are the ICD-10-PCS equivalents from the CMS General Equivalence Mappings.
About ICD-9-CM 37.21
37.21 is an ICD-9-CM procedure code for right heart cardiac catheterization. ICD-9-CM was retired for U.S. claims on October 1, 2015, when ICD-10-PCS took over.
The CMS General Equivalence Mappings translate it to 2 ICD-10-PCS codes, such as 4A020N6 (Measurement of Cardiac Sampling and Pressure, Right Heart, Open Approach) and 4A023N6 (Measurement of Cardiac Sampling and Pressure, Right Heart, Percutaneous Approach). All of these are approximate matches, so review the record to pick the right one.
ICD-10-PCS equivalents
Common questions about 37.21
What is the ICD-10 code for ICD-9 37.21?
- The GEMs map 37.21 to ICD-10-PCS 4A020N6 and 4A023N6.
GEMs are a translation aid, not a substitute for coding from the record. The 2027 ICD-10 code set has changed since the last GEMs release in 2018. Page updated September 29, 2026.