Electrocardiogram is particularly useful for cardiac involvement in primary amyloidosis. Findings on electrocardiogram include low voltage QRS complexes, left and right ventricular hypertrophy, left atrial abnormalities, pathological Q waves, and AV block.

Electrocardiogram is particularly useful for cardiac amyloidosis. Findings on an electrocardiogram include:

• Low voltage QRS complexes^[1]: Low voltages are present due to infiltrative heart disease and the reduced electrical conduction through the cardiac muscle.
• Left ventricular hypertrophy^[2]
• Right ventricular hypertrophy^[2]
• Left atrial abnormalities
• Pathological Q waves^[2]
• Atrioventricular block: AV block occur due to deposition of amyloid fibrils in the conduction tissue.
  • First-degree AV block
  • Second-degree AV block
  • Third-degree AV block