Q23.4 is the ICD-10 code for Hypoplastic left heart syndrome. It is a four-character subcategory of Q23 (Congenital malformations of aortic and mitral valves), the most specific level in the WHO edition. It belongs to the block Q20–Q28 (Congenital malformations of the circulatory system) in Chapter XVII, Congenital malformations, deformations and chromosomal abnormalities.
- Code type
- Subcategory (4 characters)
- Chapter
- XVII · Q00–Q99
- Classification
- WHO ICD-10, 2019 version
Coding notes
- Atresia, or marked hypoplasia of aortic orifice or valve, with hypoplasia of ascending aorta and defective development of left ventricle (with mitral valve stenosis or atresia).
Q23.4 in national editions
Countries report with their own edition of ICD-10. Most keep the WHO code and add more specific codes beneath it.
Q23.4Hypoplastisk venstre hjerte-syndrom
DQ234Hypoplastisk venstre hjerte-syndrom
Q23.4Vajaakehittyneen vasemman sydänpuoliskon oireyhtymä
Q23.4Hypoplastisches Linksherzsyndrom
Q23.4Hypoplasie du cœur gauche
Q23.4syndroom van hypoplastisch linkerhart
Q23.4Hypoplastic left heart syndrome
Based on the World Health Organization’s International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10), 2019 version, and the national editions published by each country’s health authority. This page is a reference, not coding advice; follow your national coding rules when you report.
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