A new screening tool for dilated cardiomyopathy in Doberman Pinschers

Purpose

To test whether speckle tracking echocardiography will be able to detect changes in the hearts of Dobermans who have abnormal 24-hour Holter monitoring but normal standard echocardiograms 

Background

Dilated cardiomyopathy (DCM) is an inherited, slowly progressive heart disease that affects up to 45% of Doberman Pinchers in the U.S. The disease has two phases. In the first phase, dogs do not have clinical signs of DCM, but changes to the heart may be seen by echocardiogram or by measuring electrical abnormalities in the heart. Over time, the disease usually progresses to the second phase, when clinical signs of congestive heart failure such as breathing problems and fainting can appear. DCM can eventually lead to death.

Early identification of DCM is essential, since treatment can delay the onset of clinical signs and prolong the dog’s life. Screening for DCM is crucial not only to identify dogs that are affected by this disease, but to support healthy breeding programs.

Current screening for DCM is costly and time consuming. A significant proportion of affected dogs have heart abnormalities that are not detectable using standard echocardiographic exams. Hence, 24-hour Holter monitor evaluation is used.

Echocardiography-derived speckle tracking (STE) is a newer technique that is rapidly gaining attention for diagnosis of DCM in humans. STE has the unique capability of non-invasively monitoring the heart with minimal additional time or cost compared to current methods. In this study, we’re testing whether STE will be able to detect changes in the hearts of Dobermans who have abnormal 24-hour Holter monitoring but normal standard echocardiograms. 

Eligibility

• Dogs must be 5 years of age or older
• Have previous Holter monitor evidence (> 300 VPCs in 24h) of heart abnormalities that may indicate the early stages of DCM
• Have previous normal echocardiogram results

Exclusion

• Have any disease that can affect the heart (e.g. hypothyroidism)
  
• Are taking any medications that affect the heart (e.g. steroids, beta blockers, diuretics, blood pressure medications)
• Are not able to tolerate gentle restraint (i.e. laying still during the approx. 20-minute echocardiogram)

Study Design

For this study, we are enrolling Dobermans who have previous Holter monitor evidence of heart abnormalities that may indicate the early stages of DCM.

Each dog will have one visit to the Veterinary Teaching Hospital in Blacksburg, VA. During the visit, dogs will undergo a physical exam and conventional echocardiography. Using special software, speckle tracking echocardiography (STE) will also be performed. STE is a non-invasive procedure that takes measurements using an ultrasound probe. A small patch of fur may be shaved for these procedures. Dogs who cannot tolerate gentle restraint for the procedures will not be enrolled in the study. Dogs will be returned to the owner at the end of the visit, and owners will be given instructions for using a 24-hour Holter monitor at home. After 24 hours, the Holter monitor will be removed by the owner according to instructions provided and returned to the VTH by either shipping with provided pre-paid label, or in person, whichever option is more convenient for you. 

Compensation

There are no costs to you for your dog to participate in the study. The study covers the costs of all study-related procedures, and all clinically-relevant results will be shared with you.