Degenerative Heart Valve Disease in Dogs (Endocardiosis)
- Occurrence: common
- Location of disease: Chest
When to visit the vet?
Non-urgent see a veterinarian within 2–3 days
If the condition worsens / symptoms persist, consult a veterinarian.
Definition
Endocardiosis, also known as degenerative mitral valve disease, is a common heart disease in dogs characterized by progressive degenerative changes in the heart valves, particularly the mitral valve.
The most important facts at a glance
Endocardiosis is a common heart disease in dogs that primarily affects the mitral valve. This valve normally prevents the backflow of blood in the heart. In endocardiosis, the valve thickens and deforms, leading to incomplete closure and backflow. The exact causes are not fully understood, but genetic factors, age, and hormonal influences play a role. Certain breeds, such as Cavalier King Charles Spaniels, are particularly susceptible. The disease usually develops over years and can be accelerated by mechanical stress and possibly by metabolic disorders.
Symptoms include heart murmurs, an increased respiratory rate, and cough. In severe cases, ascites and shortness of breath can occur. Diagnosis is made through clinical examinations, heart ultrasound, and blood tests if necessary. A cure is not possible, but medications such as diuretics and ACE inhibitors can alleviate symptoms and slow progression. Surgical interventions are rare as they are complex and costly.
The prognosis varies depending on the severity of the disease and the response to treatment. Early detection and therapy can prolong the dog’s life. Regular veterinary examinations and a healthy lifestyle are important for prevention. Research focuses on genetic studies and new treatment approaches to improve the quality of life for affected dogs.
Causes
Endocardiosis mainly affects the mitral valve, which is located between the left atrium and the left ventricle. This valve plays a crucial role in the circulatory system by preventing the backflow of blood into the left atrium during the contraction of the left ventricle. In endocardiosis, the valves thicken and deform, leading to incomplete closure and thus a backflow of blood.
The exact causes of endocardiosis are not yet fully understood, but genetics play a significant role. Certain breeds, such as Cavalier King Charles Spaniels, are particularly susceptible. Furthermore, hormonal influences and aging processes also seem to contribute to the development of the disease.
Endocardiosis usually develops over years. As the dog ages, the risk of the heart valves showing degenerative changes increases. These changes can be accelerated by mechanical stress on the valves. It is suspected that metabolic disorders and inflammatory processes may also play a role.
Symptoms
An early sign of endocardiosis is often a heart murmur that the veterinarian can detect during a routine examination. This murmur is caused by the turbulent blood flow caused by the incompletely closing mitral valve.
As the disease progresses, symptoms such as cough, shortness of breath, and reduced exercise tolerance may occur. These symptoms result from fluid accumulation in the lungs, a condition known as pulmonary edema. Affected dogs often show an increased respiratory rate and need to take breaks more frequently during walks.
In advanced stages, cardiac arrhythmia and enlargement of the left ventricle may occur. Dogs with severe endocardiosis may also show signs of heart failure, such as loss of appetite, weight loss, and weakness.
Therapy
The treatment of endocardiosis aims to alleviate the symptoms and slow the progression of the disease. There is currently no cure for the disease, but various medications can help support heart function and improve the dog’s quality of life.
Diuretics are often the first choice to remove excess fluid from the body and thus reduce the strain on the heart. ACE inhibitors are also widely used as they dilate the blood vessels and lower blood pressure, which relieves the heart.
In advanced cases, additional medications such as Digoxin or Pimobendan may be used to increase cardiac contractility and improve cardiac output. Regular adjustment of the medication is necessary to meet the changing needs of the patient.
In rare cases, surgical intervention may be considered, especially in young dogs with severe valve disease. However, such procedures are less common in dogs due to their complexity and cost.
Prognosis and follow-up care
The prognosis for dogs with endocardiosis varies greatly and depends on the severity of the disease as well as the response to treatment. Many dogs can lead a relatively normal life for years with the right treatment. Regular monitoring and adjustment of therapy are crucial to avoid complications and maintain quality of life.
In the early stages of the disease, the prognosis can be quite good, especially if it is detected and treated early. In advanced endocardiosis, particularly when signs of heart failure are present, the prognosis is more guarded. Nevertheless, many dogs can remain relatively stable over long periods with careful medical care.
Prevention
Specific prevention of endocardiosis is currently not possible, as the exact causes are not fully understood. Nevertheless, there are measures that can reduce the risk of the disease developing or progressing.
Regular veterinary examinations are crucial to detect early signs of endocardiosis. A balanced diet and a healthy weight can support cardiovascular health. For breeds susceptible to the disease, genetic counseling may be considered to minimize the risk in breeding.
It is also important to watch for signs of Respiratory distress or reduced exercise tolerance and to see a veterinarian immediately if heart problems are suspected. Early diagnosis and treatment are crucial to maintain the dog’s quality of life.
Outlook on current research
Endocardiosis, also known as myxomatous mitral valve disease, is one of the most common heart diseases in older dogs, especially small breeds. Research in this field is aimed at better understanding the exact causes and mechanisms of this degenerative change in the heart valves. Scientists are investigating genetic predispositions that can lead to an increased risk, with some studies suggesting that certain breeds, such as Cavalier King Charles Spaniels, are particularly susceptible.
A significant part of current research focuses on the development of new drug treatment approaches. The goal is to slow the progression of the disease and improve the quality of life for affected dogs. Researchers are investigating the effectiveness of ACE inhibitors, diuretics, and beta blockers in the treatment of endocardiosis. In doing so, they are trying to determine the optimal combination and dosage of these medications to achieve the best possible results.
Another exciting aspect of research is the investigation of the role of environmental factors and diet in the development of endocardiosis. Some studies suggest that a balanced diet and regular exercise could have a preventive effect, although further research is needed to confirm this assumption. Avoiding overweight is frequently recommended as a preventive measure to reduce the strain on the heart.
The use of advanced imaging technology, such as 3D echocardiography, is another important area of research. These technologies allow for a more detailed examination of the heart valves and can help to make more accurate diagnoses as well as monitor the effectiveness of treatments. The development of such technologies could revolutionize the way endocardiosis is diagnosed and treated.
Genomic studies aimed at deciphering the genetic basis of endocardiosis have also gained importance. This research could make it possible to identify genetic markers that contribute to the early detection of the disease. In the long term, this could lead to the development of targeted therapies tailored to the specific genetic profiles of the affected dogs.
A promising field of research is regenerative medicine. It is being investigated whether stem cells or regenerative therapies can be used to repair or regenerate damaged heart valves. Although this type of treatment is still in the experimental stage, the results so far are promising and could open up new ways to treat endocardiosis in the future.
In summary, research into endocardiosis in dogs is a dynamic and rapidly evolving field. It encompasses a variety of approaches, from genetics and pharmacology to imaging and regenerative medicine. These multidisciplinary efforts aim to gain a more comprehensive understanding of the disease and develop innovative treatment strategies that could significantly improve the lives of dogs with endocardiosis.
Frequently Asked Questions (FAQs)
1. What is endocardiosis in dogs?
2. What symptoms can occur in a dog with endocardiosis?
3. How is endocardiosis diagnosed?
4. Is endocardiosis curable?
5. Are certain breeds particularly susceptible to endocardiosis?
6. What treatments are available for dogs with endocardiosis?
7. How can I help my dog with endocardiosis lead a good life?
8. Are there preventive measures against endocardiosis?
9. How does endocardiosis affect a dog's quality of life?
10. Can endocardiosis lead to other health problems?
Literature
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- Boswood, A., Häggström, J., Gordon, S. G., Wess, G., Stepien, R. L., Oyama, M. A., Keene, B. W., Bonagura, J., MacDonald, K. A., Patteson, M., Smith, S., Fox, P. R., Sanderson, K., Woolley, R., Szatmári, V., Menaut, P., Church, W. M., O’Sullivan, M. L., Jaudon, J.-P., … Watson, P. (2016). Effect of pimobendan in dogs with preclinical myxomatous mitral valve disease and cardiomegaly: The EPIC Study—A randomized clinical trial. Journal of Veterinary Internal Medicine, 30(6), 1765–1779. https://doi.org/10.1111/jvim.14586
- Häggström, J., Boswood, A., O’Grady, M., Jöns, O., Smith, S., Swift, S., Borgarelli, M., Gavaghan, B., Kresken, J.-G., Patteson, M., Åblad, B., Bussadori, C. M., Glaus, T., Kovacević, A., Rapp, M., Santilli, R. A., Tidholm, A., Eriksson, A., Belanger, M. C., … DiFruscia, R. (2008). Effect of pimobendan or benazepril hydrochloride on survival times in dogs with congestive heart failure caused by naturally occurring myxomatous mitral valve disease: The QUEST study. Journal of Veterinary Internal Medicine, 22(5), 1124–1135. https://doi.org/10.1111/j.1939-1676.2008.0150.x
- Borgarelli, M., Ferasin, L., Lamb, K., Bussadori, C., Chiavegato, D., D’Agnolo, G., Migliorini, F., Poggi, M., Santilli, R. A., Guillot, E., Garelli-Paar, C., Toschi Corneliani, R., Farina, F., Zani, A., Dirven, M., Smets, P., Guglielmini, C., Oliveira, P., Di Marcello, M., … Baron Toaldo, M. (2020). DELay of appearance of sYmptoms of canine degenerative mitral valve disease treated with spironolactone and benazepril: The DELAY Study. Journal of Veterinary Cardiology, 27, 34–53. https://doi.org/10.1016/j.jvc.2019.12.002
- Mattin, M. J., Boswood, A., Church, D. B., López-Alvarez, J., McGreevy, P. D., O’Neill, D. G., Thomson, P. C., & Brodbelt, D. C. (2015). Prevalence of and risk factors for degenerative mitral valve disease in dogs attending primary-care veterinary practices in England. Journal of Veterinary Internal Medicine, 29(3), 847–854. https://doi.org/10.1111/jvim.12591
- Svensson, M., Selling, J., & Dirven, M. (2024). Myxomatous mitral valve disease in large-breed dogs: Survival characteristics and prognostic variables. Veterinary Sciences, 11(3), 136. https://doi.org/10.3390/vetsci11030136
- Borgarelli, M., & Häggström, J. (2010). Canine degenerative myxomatous mitral valve disease: Natural history, clinical presentation and therapy. Veterinary Clinics of North America: Small Animal Practice, 40(4), 651–663. https://doi.org/10.1016/j.cvsm.2010.03.008