SignalRAY Update - January 2022

We're excited to announce a new cardiac test for Left Atrial Enlargement that will help you gain more value from your thoracic radiographs! The following change will go into effect on January 14th, 2022.

Assessment for enlargement of the left atrium will now be performed in your canine patients. The newly developed LAE test will be included in your SignalRAY reports with either normal or abnormal results displayed.


Example of Abnormal Left Atrial Enlargement


  • Left atrial enlargement is the most common cardiac enlargement observed on radiographs. The presence of left atrial enlargement indicates cardiac disease and it can predict the development of congestive heart failure. Also known as LAE, it is most commonly caused by mitral valve disease.
  • Even though Vertebral heart Score (VHS) also assesses the heart size, it may not always be accurate or reflective of enlargement; due to different factors affecting measurements including breed, positioning of the patient, respiratory phase, etc.

LAE - Left Atrial Enlargement

Test description: Assessment for evidence of enlargement of the left atrium
DDx: Valvular disease, cardiomyopathy, other
Abnormal description: Left atrial size is assessed on the lateral view based on the appearance of a bulge at the dorsocaudal cardiac border, straightening of the caudal heart border, widening of the cardiac silhouette at the heart base, and dorsal displacement of the trachea. An abnormal test indicates that there is an enlargement of the left atrium based on the presence of one or multiple characteristics listed above. In some instances, a heart base mass or hilar mass cannot be distinguished from an enlarged left atrium. Primary differential diagnoses for left atrial enlargement include mitral valve disease, cardiomyopathy, congenital heart disease, or left ventricular failure. Further testing including echocardiography should be considered for definitive diagnosis.