2006 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Circulatory System 390-459 > Other Forms Of Heart Disease 420-429 > Acute And Subacute Endocarditis 421.* > 2006 ICD-9-CM Diagnosis 421.9 Acute endocarditis unspecified View the most recent version of ICD-9-CM 421.9 421.9 is a specific code that can be used to specify a diagnosis 421.9 contains 8 index entries View the ICD-9-CM Volume 1 421.* hierarchy Alternate Terminology Endocarditis, acute or subacute Myoendocarditis, acute or subacute Periendocarditis, acute or subacute 421.9 Excludes acute rheumatic endocarditis (391.1)  Index entries containing 421.9: Endocarditis (chronic) (indeterminate) (interstitial) (marantis) (nonbacterial thrombotic) (residual) (sclerotic) (sclerous) (senile) (valvular) 424.90 acute or subacute 421.9 rheumatic (aortic) (mitral) (pulmonary) (tricuspid) 391.1 with chorea (acute) (rheumatic) (Sydenham's) 392.0 aortic (heart) (nonrheumatic) (valve) 424.1 acute or subacute 421.9 mitral (chronic) (double) (fibroid) (heart) (inactive) (valve) (with chorea) 394.9 nonrheumatic 424.0 acute or subacute 421.9 pulmonary (chronic) (heart) (valve) 424.3 acute or subacute 421.9 rheumatic 391.1 with chorea (acute) (rheumatic) (Sydenham's) 392.0 toxic (see also Endocarditis, acute) 421.9 tricuspid (chronic) (heart) (inactive) (rheumatic) (valve) (with chorea) 397.0 nonrheumatic 424.2 acute or subacute 421.9 Myoendocarditis - see also Endocarditis acute or subacute 421.9 Periendocarditis (see also Endocarditis) 424.90 acute or subacute 421.9