Part 1: New ICD-10 Codes and IPPS Changes for 2020


New ICD-10-CM Codes

This is Part 1 of a 4 part series on the FY2020 changes to ICD-10 and the IPPS.  In this part, we discuss some of  the new ICD-10-CM diagnosis changes. Here is the breakdown:

72,184 total ICD-10-CM codes for FY2020

  • 324 changes all together (2019 had 473 changes)
  • 273 new codes (2019 had 279 new codes)
  • 21 deleted codes (2019 had 51 deleted codes)
  • 30 revised codes (2019 had 143 revised codes)

Most of the changes occurred in the circulatory system, skin and subcutaneous system, congenital malformations, injuries, external causes and status codes chapters. The major changes will be discussed below.

Circulatory System Chapter

The first big change involves Type 2 Myocardial Infarction (MI)​​​.  The OCG and notes in the tabular have been revised to state that the coder must CODE FIRST the underlying cause of the Type 2 MI such as:  anemia (D50.0-D64.9); COPD (J44.-); paroxysmal tachycardia (I47.0-I47.9), shock (R57.0-R57.9).  Code I21.A1 should never appear as a principal diagnosis.

Type 2 MI (myocardial infarction) is marked by non-ST elevation, and occurs secondary to cardiac stress due to other causes (i.e., ischemia resulting from a supply-and-demand mismatch), without atherosclerotic plaque rupture, but with myocardial necrosis.

Type 2 MI patients may have elevated troponin but no real clinical features of a Type I MI. The underlying cause usually is increasing the oxygen demand or decreasing the oxygen supply. Treating the underlying cause corrects this.

Troponin can be elevated by non-cardiac causes such as renal failure, significant age and other conditions listed. An elevated troponin and a normal ECG or nonspecific changes should raise suspicion of an alternate diagnosis. Elevated troponin (R79.89) does not always equal Type 2 or other MI. The coder may need to query if this is the case.

The second major change is the addition of various codes for different types of atrial fibrillation.

I48.1 Persistent atrial fibrillation

    Add  Excludes1: Permanent atrial fibrillation (I48.21)

Add  I48.11 Longstanding persistent atrial fibrillation  (CC)

Add  I48.19 Other persistent atrial fibrillation (CC)

Add   Chronic persistent atrial fibrillation

Add   Persistent atrial fibrillation, NOS

I48.2 Chronic atrial fibrillation

      Delete  Permanent atrial fibrillation

      Add       I48.20 Chronic atrial fibrillation, unspecified (CC)

               Add   Excludes1: Chronic persistent atrial fibrillation (I48.19)

      Add       I48.21 Permanent atrial fibrillation (CC)


Atrial Fibrillation definitions are categorized by duration, and can change over time.

Persistent Atrial Fibrillation (I48.19)

Usually, this lasts longer than a week. It could stop on its own, or patient may need medicine or treatment to stop it. Doctors can use medicine such as Amiodarone to treat this type of AFib. If that doesn’t work, they might use a low-voltage current to reset the heart’s rhythm to normal (called electrical cardioversion.) Pacemaker is sometimes placed.

Long-Standing Persistent Atrial Fibrillation (I48.11)

This means the AFib has lasted for more than a year and doesn’t go away. Medicine and treatment such as electrical cardioversion may not stop the AFib. Doctors can use another kind of treatment, such as ablation (which burns certain areas of your heart’s electrical system) to restore patient to normal heart rhythm. Or can try the MAZE procedure.  Pacemaker sometimes placed.

Permanent Atrial Fibrillation (I48.21)

This can’t be corrected by treatments. Patient and doctor will decide if patient needs long-term medication to control heart rate and lower odds of having a stroke. Usually nothing can correct it.

Paroxysmal Atrial Fibrillation (I48.0)

This is an episode of atrial fibrillation that lasts less than a week. Patient might feel it happening for a few minutes or for several days. May not need treatment with this type of AFib, but you should see a doctor.  Sometimes Beta Blockers, pulmonary vein isolation or radiofrequency ablation used.

Chronic Atrial Fibrillation (I48.20)

The MD documents ‘chronic’ but does not know exact type.  Usually means more than 1 week although there are more precise definitions above.  The physician can be queried.

The question comes up as to what to do when a physician documents two types of atrial fibrillation, such as paroxysmal atrial fibrillation (PAT) and persistent atrial fibrillation. Since the definitions are by duration, best practice would be to query and educate physicians on new codes and importance of discerning the exact type of atrial fibrillation.   Since it can change over time, the patient may have had paroxysmal atrial fib in the past in the history section that now has persistent atrial fibrillation.  Also the abbreviation of PAT must be reviewed as it may stand for paroxysmal or persistent or even permanent atrial fibrillation. This abbreviation is best avoided.

Skin and Subcutaneous System Chapter

The most prominent change here is the addition of “Pressure-induced deep tissue damage” codes of the various sites of the body to include elbow, upper/lower back, sacrum, hip, buttock, ankle, heel, other, unspecified. All are “CCs” and have the sixth character of “6.”   These were previously indexed to “Unstageable” ulcers.  Pressure-induced deep tissue damage is also referred to as Deep Tissue Pressure Injury (DTPI) is now defined as “intact or non-intact skin with localized area of persistent non-blanchable deep red, maroon, purple discoloration or epidermal separation revealing a dark wound bed or blood filled blister. Pain and temperature change often precede skin color changes. Discoloration may appear differently in darkly pigmented skin. This condition results from intense and/or prolonged pressure and shear forces at the bone-muscle interface. The wound may evolve rapidly to reveal the actual extent of tissue injury, or may resolve without tissue loss.”  Coders will need to be especially careful in indexing these codes.  The index under injury, deep tissue meaning pressure ulcer states to code to the ulcer, pressure unstageable. However, if deep tissue injury is present, the L89 codes should be used, not the unstageable codes.  The index entry will be revised in the future. Please refer to 4Q2019 Coding Clinic page 11.

Congenital Malformations and Abnormalities Chapter

Many new codes were added to describe the laterality of congenital disorders of talipes equinovarus, talipes calaneovarus, metatarsus primus varus, metatarsus adductus, varus deformities, talipes calcaneovalgus, pes cavus, and deformity of feet.

New codes were added for the various types of Ehlers-Danlos Syndromes.  This affects 1 in 5000 individuals.  Ehlers-Danlos syndrome is a group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues. Defects in connective tissues cause the signs and symptoms of these conditions, which range from mildly loose joints to life-threatening complications such as aortic root issues.  Subtypes usually diagnosed by knowing the gene mutation.

Injuries Chapter

Most of the new codes in this chapter have to do with a creation of 60 new codes for fractures of the orbital roof, medial orbital wall, lateral orbital wall and orbital floor (S02.121-29, S02.8-).    This can be confusing to coders as different bones make up each designation:

Orbital Roof:    frontal bone, lesser wing of sphenoid

Lateral Orbital Wall:  zygomatic bone, greater wing of sphenoid

      Orbital Floor:  maxillary, zygomatic, and palatine bones

Medial Orbital Wall:  maxillary, lacrimal, ethmoid and sphenoid bones

18 new codes in the T50.91- category were created for poisoning by, adverse effect of and underdosing of multiple unspecified drugs, medicaments and biological substances.  There is a note to assign codes for individual specific drug codes in addition to the T50.91- codes when applicable.  The intent of creation of this code was to allow coding of poisoning and adverse effects when the specific drugs are not known by the patient, or maybe one or some drugs are known but not all that were taken.   In that case the individual drug codes would be coded along with a code from T50.91-.  There is no sequencing directive.

External Causes Chapter

New codes created in this chapter are for identification of an “Unspecified person” in the legal intervention codes Y35.00-Y35.99.   This choice was not available when the person injury was unknown. A new subsection for “legal intervention involving conduction energy device” such as stun gun or taser was added.

Factors Influencing Health Status Chapter

There are various new “Z” codes for encounter for exam of eyes and vision following failed vision screening, latent tuberculosis encounter, carrier or personal history; and Encounter for health counseling related to travel.

Z45.42 was revised to Encounter for adjustment and management of NEUROSTIMULATOR to accommodate any type of neurostimulator such as brain, gastric, peripheral nerve, spinal cord, vagus nerve and sacral nerve. Code Z96.82 Presence of neurostimulator as added.

Official Guidelines for Coding and Reporting

Most of the changes and updates have to do with the tabular changes this year such as sequencing rule for Type 2 MI and Pressure-induced deep tissue damage. There was an addition to Chapter 19 guidelines for

3) Iatrogenic injuries.  It states “Injury codes from Chapter 19 should not be assigned for injuries that occur during, or as a result of, a medical intervention. Assign the appropriate complication code(s).” What this means is don’t assign a traumatic laceration “S” code when the laceration is due to surgeon such as K91.71, laceration of digestive organ during digestive system procedure.

At the beginning of Chapter 19 is this:  Note: The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.  Consequently under guideline g for

“Complications of care, this note was added:  Complication codes from the body system chapters should be assigned for intraoperative and postprocedural complications (e.g., the appropriate complication code from chapter 9 would be assigned for a vascular intraoperative or postprocedural complication) unless the complication is specifically indexed to a T code in chapter 19.

For section III and IV, C. Uncertain Diagnosis, the terms “compatible with” and “consistent with” were added as terms that indicate the same meaning as “probable,” “likely,” and “questionable.”

So that about sums it up. No real earth shattering changes to ICD-10-CM except for maybe the new atrial fibrillation codes and Type 2 MI sequencing directives.  Be sure to review all the other changes in the addenda.

In Part 2 of this series, we will look at some highlights of the new ICD-10-PCS codes and changes.

The information contained in this coding advice is valid at the time of posting. Viewers are encouraged to research subsequent official guidance in the areas associated with the topic as they can change rapidly.

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