Home > 2015 ICD-9-CM Diagnosis Codes > Diseases Of The Circulatory System 390-459 > Other Forms Of Heart Disease 420-429 > Acute and subacute endocarditis 421-
Specific code 2015 ICD-9-CM Diagnosis Code 421.0
Acute and subacute bacterial endocarditis
  • 2015
  • Billable Thru Sept 30/2015
  • Non-Billable On/After Oct 1/2015

  • ICD-9-CM 421.0 is a billable medical code that can be used to indicate a diagnosis on a reimbursement claim, however, 421.0 should only be used for claims with a date of service on or before September 30, 2015. For claims with a date of service on or after October 1, 2015, use an equivalent ICD-10-CM code (or codes).
Convert to ICD-10-CM: 421.0 converts approximately to:
  • 2015/16 ICD-10-CM I33.0 Acute and subacute infective endocarditis
Approximate Synonyms
  • Acute or subacute mycotic aneurysm
  • Bacterial endocarditis
  • Bacterial endocarditis (infection of heart valve)
  • Endocarditis, bacterial
  • Fungal endocarditis
  • Mycotic aneurysm
  • Mycotic aneurysm due to bacterial endocarditis
  • Mycotic aneurysm, due to bacterial endocarditis
  • Mycotic endocarditis
Clinical Information
  • Infection occuring when bacteria in the bloodstream (bacteremia) adhere to abnormal heart valves or other damaged heart tissue; characterized by growths, known as vegetations, on the valves or other areas of the heart which can break off, travel to other parts of the body, and cause serious complications; a common causative bacteria is staphylococcus, but any organism entering the bloodstream from any site of prior infection can result in the infection
  • Subacute inflammation of the endocardium. Streptococcus viridans is the usual etiologic agent of sbe. The distinction between "acute" and "subacute" endocarditis has traditionally been made based on the pathogenic organism and clinical presentation
Applies To
  • Endocarditis (acute) (chronic) (subacute):
    • bacterial
    • infective NOS
    • lenta
    • malignant
    • purulent
    • septic
    • ulcerative
    • vegetative
  • Infective aneurysm
  • Subacute bacterial endocarditis [SBE]
Use Additional
  • Use additional code, if desired, to identify infectious organism [e.g., Streptococcus 041.0, Staphylococcus 041.1]
ICD-9-CM Volume 2 Index entries containing back-references to 421.0:
  • Aneurysm (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (ruptured) (saccular) (varicose) 442.9
    • brain 437.3
      • arteriosclerotic 437.3
        • ruptured (see also Hemorrhage, subarachnoid) 430
      • arteriovenous 747.81
        • acquired 437.3
          • ruptured (see also Hemorrhage, subarachnoid) 430
        • ruptured (see also Hemorrhage, subarachnoid) 430
      • berry (congenital) (ruptured) (see also Hemorrhage, subarachnoid) 430
      • congenital 747.81
        • ruptured (see also Hemorrhage, subarachnoid) 430
      • meninges 437.3
        • ruptured (see also Hemorrhage, subarachnoid) 430
      • miliary (congenital) (ruptured) (see also Hemorrhage, subarachnoid) 430
      • mycotic 421.0
        • ruptured (see also Hemorrhage, subarachnoid) 430
      • nonruptured 437.3
      • ruptured (see also Hemorrhage, subarachnoid) 430
      • syphilitic (hemorrhage) 094.87
      • traumatic - see Injury, intracranial
    • endocardial, infective (any valve) 421.0
    • infective (any valve) 421.0
    • mycotic, any site 421.0
      • without endocarditis - see Aneurysm, by site
      • ruptured, brain (see also Hemorrhage, subarachnoid) 430
  • Endocarditis (chronic) (indeterminate) (interstitial) (marantic) (nonbacterial thrombotic) (residual) (sclerotic) (sclerous) (senile) (valvular) 424.90
    • aortic (heart) (nonrheumatic) (valve) 424.1
      • with
        • mitral (valve) disease 396.9
          • active or acute 391.1
            • with chorea (acute) (rheumatic) (Sydenham's) 392.0
            • bacterial 421.0
        • rheumatic fever (conditions classifiable to 390)
          • active - see Endocarditis, acute, rheumatic
          • inactive or quiescent (with chorea) 395.9
            • with mitral disease 396.9
      • acute or subacute 421.9
      • arteriosclerotic 424.1
      • congenital 746.89
      • hypertensive 424.1
      • rheumatic (chronic) (inactive) 395.9
        • with mitral (valve) disease 396.9
          • active or acute 391.1
            • with chorea (acute) (rheumatic) (Sydenham's) 392.0
        • active or acute 391.1
          • with chorea (acute) (rheumatic) (Sydenham's) 392.0
      • specified cause, except rheumatic 424.1
      • syphilitic 093.22
    • bacterial (acute) (any valve) (chronic) (subacute) 421.0
    • constrictive 421.0
    • infectious or infective (acute) (any valve) (chronic) (subacute) 421.0
    • lenta (acute) (any valve) (chronic) (subacute) 421.0
    • Loeffler's (parietal fibroplastic) 421.0
    • malignant (acute) (any valve) (chronic) (subacute) 421.0
    • mitral (chronic) (double) (fibroid) (heart) (inactive) (valve) (with chorea) 394.9
      • with
        • aortic (valve) disease 396.9
          • active or acute 391.1
            • with chorea (acute) (rheumatic) (Sydenham's) 392.0
        • rheumatic fever (conditions classifiable to 390)
          • active - see Endocarditis, acute, rheumatic
          • inactive or quiescent (with chorea) 394.9
            • with aortic valve disease 396.9
      • active or acute 391.1
        • with chorea (acute) (rheumatic) (Sydenham's) 392.0
        • bacterial 421.0
      • arteriosclerotic 424.0
      • congenital 746.89
      • hypertensive 424.0
      • nonrheumatic 424.0
      • syphilitic 093.21
    • mycotic (acute) (any valve) (chronic) (subacute) 421.0
    • pneumococcic (acute) (any valve) (chronic) (subacute) 421.0
    • purulent (acute) (any valve) (chronic) (subacute) 421.0
    • septic (acute) (any valve) (chronic) (subacute) 421.0
    • streptococcal (acute) (any valve) (chronic) (subacute) 421.0
    • suppurative (any valve) (acute) (chronic) (subacute) 421.0
    • ulcerative (acute) (any valve) (chronic) (subacute) 421.0
    • vegetative (acute) (any valve) (chronic) (subacute) 421.0
  • Infection, infected, infective (opportunistic) 136.9
    • endocardium (see also Endocarditis) 421.0
  • Löffler's
    • endocarditis 421.0
  • Node(s) - see also Nodules
    • Osler's 421.0
  • Osler's
    • nodes 421.0
  • SBE (subacute bacterial endocarditis) 421.0
  • Ulcer, ulcerated, ulcerating, ulceration, ulcerative 707.9
    • endocarditis (any valve) (acute) (chronic) (subacute) 421.0
    • valve, heart 421.0
  • Vegetation, vegetative
    • endocarditis (acute) (any valve) (chronic) (subacute) 421.0
    • heart (mycotic) (valve) 421.0
 421 ICD9Data.com 421.1 
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