Coding Heart Failure

This installment of “In the kNOW” is going to review recent Coding Clinic information related to the coding of heart failure.  First, let’s review heart failure in general noting that there are three types of heart failure: left-sided, right-sided, and congestive.

In left-sided heart failure, the blood is not pumped out to the rest of the body efficiently causing the left ventricle to work harder to supply blood flow.  There are two types of left-sided heart failure: heart failure with reduced ejection fraction (HFrEF)(systolic), and heart failure with preserved ejection fraction (HFpEF)(diastolic).  The ejection fraction is a measurement (percentage) of how much blood is being pumped out by the left ventricle with each contraction.  Normal ejection fractions generally run between 50%-70%.  In heart failure with preserved ejection fraction, contraction of heart muscles is normal, but relaxation of the ventricles is abnormal due to stiffness, thus limiting the amount of blood that can fill the heart.  In heart failure with reduced ejection fraction, the contraction part of the process is abnormal and not enough blood enters the circulation.  Because the terminology of HFrER and HFpEF is more widely accepted now, coders may use those terms to assign codes for systolic or diastolic heart failure respectively or a combination of both if applicable.  Keep in mind that additional clarifying terms may impact code assignment, such as acute, chronic, or acute on chronic.   

                                    Acute                   Chronic           Acute on Chronic       Unspecified
Systolic                        I50.21                    I50.22              I50.23                           I50.20
Diastolic                       I50.31                    I50.32              I50.33                           I50.30
Systolic & Diastolic       I50.41                    I50.42              I50.43                           I50.40
Unspecified                                                                                                          I50.9

Left-sided heart failure is often the precursor for right-sided heart failure.  Failure of left ventricular function causes a back-up of pressure to the lungs and ultimately, the right side of the heart.  This domino effect continues with fluid backing-up in the veins.

Congestive heart failure (CHF) (I50.9) is manifested with swelling in bodily tissues, especially legs and ankles.  Shortness of breath may occur when fluid backs-up and collects in lung tissue (pulmonary edema).  CHF happens when the heart is not pumping out blood at a normal rate, and back-up into the veins occurs.  

It is important to note that the American Heart Association has established a classification system for heart failure, A-D.  Class or stage A means that objectively there is no evidence of cardiovascular disease, and that ordinary physical activity is not limited and does not produce any symptoms.  Bearing this in mind, Coding Clinic has indicated that it is inappropriate to code stage A heart failure to I50.9 as the patient does not yet have the disease, even though they have risk factors.  Coders are therefore instructed to use Z91.89, Other specified personal risk factors, not elsewhere classified, to indicate the increased risk status.  Additional codes could be assigned for other conditions which might factor into the risk level such as hypertension or coronary artery disease.

When systolic/diastolic dysfunction is noted along with congestive heart failure, there must be linkage in the documentation to assign systolic or diastolic CHF.  For example, if documentation states chronic CHF with systolic dysfunction, the provider has indicated a relationship using the term “with” so code I50.22 can be assigned.  If on the other hand, the provider stated chronic CHF and systolic dysfunction, there is no linkage and only code I50.9 can be assigned.

Finally, coders have been instructed to assign I11.0 (hypertensive heart disease) in conjunction with an I50.- (heart failure) code to correctly code hypertension and heart failure even in the absence of provider documentation specifically linking the two conditions.  Coders are reminded that there is a presumptive relationship between hypertension and heart involvement, and that these conditions should be coded using the combination code of I11.0 and then the appropriate heart failure code by following the “use additional code” note unless documentation by the provider states that the conditions are unrelated. 

Now you are In the KNOW!! 

About the Author 

Dianna Foley, RHIA, CHPS, CCS  is OHIMA's Coding Education Coordinator. Dianna has been an HIM professional for 20 years. She progressed through the ranks of coder, department supervisor, and department director, to her current role as a coding consultant. 

She recently served as the program director for Medical Coding and HIT at Eastern Gateway Community College. Dianna earned her bachelor's degree from the University of Cincinnati subsequently achieving her RHIA, CHPS, and CCS certifications. She is an AHIMA Approved ICD-10-CM/PCS Trainer and a a presenter at regional HIM meetings and the OHIMA Annual Meeting.