Cardiac Amyloidosis Light Chain Disease; Light Chain Cardiac Amyloidosis; Primary Cardiac Amyloidosis

Cardiac amyloidosis - AL type is a rare heart disease caused by deposits of abnormal protein (amyloid) in the heart tissue. These proteins slowly replace normal heart tissue causing the heart to become stiff. Individuals with this disease often experience difficulties with the way in which electrical signals move through the heart conduction system. These electrical disturbances can lead to arrhythmias and heart block. Heart function also becomes reduced.

Adjudicators are reminded to not confuse cardiac amyloidosis - AL type with other types of amyloidosis with cardiac involvement (e.g. familial or senile age related transthyretin (ATTR) and secondary (AA) amyloidosis). These types of amyloidosis are also known as heavy chain amyloidosis. Although they can also affect the heart, their severity and progression are variable and must be evaluated on a case-by-case basis.

Diagnostic testing: The diagnosis of cardiac amyloidosis - AL type is made by:

• •

  Chest or abdomen computed tomography (CT) scan;

• •

  Coronary angiography;

• •

  Echocardiogram;

• •

  Magnetic resonance imaging (MRI); and

• •

  Nuclear heart scans help diagnose cardiac amyloidosis light chain disease.

A tissue biopsy (not necessarily of the heart) confirms the diagnosis.

Physical findings: Symptoms and signs may be similar to what is seen in congestive heart failure and may include:

• •

  Excessive fluid retention;

• •

  Excessive urination at night;

• •

  Fatigue;

• •

  Heart palpitations;

• •

  Shortness of breath with activity;

• •

  Swelling of the legs and ankles; and

• •

  Difficulty breathing while lying down.

ICD-9: 277.3; 427.x; 428.x

ICD-10: I43

Cardiac amyloidosis - AL type is a chronic condition that rapidly worsens. The median survival of individuals diagnosed with this condition is about one year.

Medical therapy of individuals with cardiac amyloidosis AL type is only of limited value. Heart transplantation may also be considered; and it usually increases life expectancy, although it is often less than that of other heart transplant recipients.

Suggested MER for Evaluation:

• •

  Clinical examination that describes the diagnostic features of cardiac involvement; and

• •

  Tissue biopsy.

Suggested Listings for Evaluation:

4.02

4.05