- Arsenism 985.1
- Arterial - see condition
- Arteriectasis 447.8
- Arteriofibrosis - see Arteriosclerosis
- Arteriolar sclerosis - see Arteriosclerosis
- Arteriolith - see Arteriosclerosis
- Arteriolitis 447.6
- Arteriolosclerosis - see Arteriosclerosis
- Arterionephrosclerosis (see also Hypertension, kidney) 403.90
- Arteriopathy 447.9
- Arteriosclerosis, arteriosclerotic (artery) (deformans) (diffuse) (disease) (endarteritis) (general) (obliterans) (obliterative) (occlusive) (senile) (with calcification) 440.9
- Arteriospasm 443.9
- Arteriovenous - see condition
- Arteritis 447.6
- Artery, arterial - see condition
- Arthralgia (see also Pain, joint) 719.4
- Arthritis, arthritic (acute) (chronic) (subacute) 716.9
- Arthro-onychodysplasia 756.89
- Arthro-osteo-onychodysplasia 756.89
- Arthrocele (see also Effusion, joint) 719.0
- Arthrochondritis - see Arthritis
- Arthrodesis status V45.4
