Minimally Invasive Mitral Valve Repair in Dogs with Chronic Mitral Valve Disease (CVD)

Study Progress Update

As of August 2018, we are actively seeking two dogs to enroll in this pilot study. Please read all enrollment criteria carefully, and discuss the study with your dog's cardiologist or veterinarian. Dogs must meet all conditions of eligibility in order to be considered.


To establish the long-term effects of a procedure to repair the mitral valve in dogs with naturally occurring, advanced CVD using a minimally-invasive surgical approach.


Current treatment for mitral valve disease is medical (i.e. drugs) and is intended to control the clinical signs of this disease. However, none of the medical treatments affect the mechanism primarily responsible for the development of clinical signs: mitral regurgitation (leakage through the mitral valve). In humans, the standard of care for patients with this disease is surgical mitral repair, but the procedure’s invasiveness, complexity, and high cost have limited its implementation in veterinary medicine. Driven by the same obstacles, minimally-invasive mitral repair is currently being successfully used in humans.

This study is intended to assess the efficacy and long-term effects of minimally-invasive repair of the mitral valve on a beating heart using a novel device. Our group has already demonstrated that this procedure is feasible and safe. We now offer the possibility to use this procedure in dogs with naturally occurring, advanced CVD.

We are studying the use of this device in canine patients, and we have no long-term safety or efficacy data for canine use. Based on human and preclinical animal studies, we believe this approach can be successful in canine patients. However, please be aware that this procedure may result in the worsening of your dog’s condition and possibly even death. Therefore we are seeking dogs whose heart disease can no longer be controlled by medication.


We are seeking dogs with endocardiosis (mitral valve disease) who have:

  • Diagnosis of chronic mitral valve disease and at least one re-occurrence of congestive heart failure (CHF) despite medical management.

    CHF occurs when fluid accumulates in the chest. Dogs may experience acute symptoms such as difficulty breathing, fainting, or persistent cough. CHF is usually diagnosed using chest x-rays. If you're not sure if your dog has experienced recurrent CHF, please ask his/her cardiologist before contacting us.

  • Significant cardiomegaly (enlarged heart)
  • Body weight greater than 5kg (11 pounds). Dogs must be larger than 11 lbs. in order for us to successfuly perform the procedure. Dogs smaller than 11 lbs. are not eligible.

In order to evaluate your dog’s suitability for the procedure, we need:

  • Medical records
  • List of current medications and dosages
  • Recent x-rays (last six months)
  • Recent echocardiographic imaging and video loops (last six months)

These screening assessments do not need to be performed at our hospital. The cost of these assessments is not covered by the study. Please contact study coordinator Mindy Quigley to discuss the study or your dog’s potential enrollment.

Exclusion Criteria

  • Dogs with mitral valve disease that do not have an enlarged heart
  • Dogs who have not experienced any episodes of congestive heart failure (CHF)
  • Dogs who have other serious diseases such as kidney disease
  • Dogs weighing less than 5 kg (11 pounds)

Study Design

The repair procedure and follow-up visits must be done at Virginia-Maryland College of Veterinary Medicine in Blacksburg, VA. Dogs will undergo standard echocardiographic examination to establish baseline measurements and confirm that they meet specific criteria. Eligible dogs will be anesthetized and the investigational device will be introduced into the heart in order to repair the mitral valve. Dogs will be hospitalized up to the full recovery from the procedure, usually 7-10 days post-op. Periodic rechecks (3, 7, 15, 30 and 60 days post procedure) will be performed to assess function of the mitral valve after the repair.


Enrolled dogs will receive, at no cost, a physical examination/office visit, blood work, thoracic radiographs, complete echocardiographic examination, the repair procedure and post procedure hospitalization. Cardiac rechecks at 3, 7, 15, 30 and 60 days post procedure are also included at no cost. The costs of an initial screening exam may be waived for patients that are likely to be eligible.


My dog meets some, but not all of the eligibility requirements. Can you make an exception and enroll him?

No. Because of the pioneering nature of this procedure, all eligibility criteria must be met.

My dog was recently diagnosed with mitral valve disease. Can she enroll in your study?

Typically, no. Recently-diagnosed dogs are usually in an early phase of the disease. We are looking for dogs with end-stage disease. Occasionally, dogs will have an acute onset of severe disease. In those cases, your dog may be eligible. Please ask your dog's cardiologist if you're unsure.

My dog isn't currently eligible. Could you add him to your waiting list?

We do not keep a waiting list, but you are welcome to check back in a few months' time or if your dog's disease suddenly worsens.

When will this procedure be widely available?

The continuation of this research depends on the success of these surgeries and on our ability to get funding to continue this line of investigation.

How safe is this procedure?

We have no data on the long-term safety of the procedure. The current study is designed to gather that data. In our preliminary studies, the risk of mortality was around 50%. New screening procedures and better pre-surgical simulations are likely to improve the chances of success.


Mindy Quigley, Clinical Trials Coordinator
Office Phone: 540-231-1363 | Email:

Dr. Michele Borgarelli, Principal Investigator, Professor, Cardiology
Phone: 540-231-4621

If your query is urgent, please call the Small Animal Hospital on 540-231-4621 and ask for the cardiologist on duty.