Stenosis is the narrowing or obstruction of an opening or passage within the body due to congenital or degenerative development. In dogs, stenosis typically affects areas within the spine, such as lumbosacral or cervical stenosis, or in the heart, such as aortic or pulmonic stenosis. Symptom severity and treatment options depend on the level of narrowing in the area affected.
Aortic stenosis is a congenital condition affecting the heart's aortic valve, reducing the flow of oxygenated blood from the left ventricle into the body. Subaortic stenosis affects the area below the aortic valve. Mild cases often show no symptoms; severe cases can lead to sudden death. Symptoms include exercise intolerance, difficulty breathing, coughing and fainting due to a lack of oxygen. Predisposition of aortic stenosis occurs in Bouvier de Flanders, boxers, bull terriers, golden retrievers, German shepherds, English bulldogs, Rottweilers and Newfoundlands. This condition causes heart murmurs and irregular heartbeats. Your veterinarian may prescribe beta-blockers to reduce the stress on the heart and minimize irregular heartbeats. In some cases, surgery to open the blockage is recommended.
Pulmonic stenosis is a congenital condition that affects the pulmonary valve in the heart. Three types of pulmonic stenosis exist, dependent on where on the heart they form. Valvular pulmonic stenosis affects the valve. Subvalvular pulmonic stenosis affects the area just below the valve, and supravalvular pulmonic stenosis affects the inside of the pulmonary artery. In mind cases, often no symptoms present. In more severe cases, you may notice abdominal distension, difficulty breathing or problems with exercising. In severe narrowing, congestive heart failure can occur. Mild cases often require no treatment. If the narrowing affects heart function, balloon catheter dilation or valvuloplasty surgery will help to repair and open the obstructing area.
Lumbosacral stenosis, also known as canine equine syndrome, is a congenital ordegenerative condition that causes narrowing in the vertebral canal. This narrowing places pressure on the spinal nerves. The congenital condition typically affects small to medium-size dogs; the degenerative condition occurs in larger dogs, especially boxers, German shepherds and Rottweilers. Symptoms include pain in the lumbar region of the spine, pelvic weakness, lameness, tail weakness or paralysis, and urine and fecal incontinence. Treatment involves surgical intervention to reduce the pressure on the spinal nerves.
Cervical stenosis, also known as Wobbler syndrome or cervical spondylopathy, is similar to lumbosacral stenosis in that it causes compression of spinal nerves. The difference is that this compression occurs in the cervical section of the spine, near the base of the neck. Symptoms vary from minor lack of coordination to full limb paralysis. The condition typically affects breeds such as basset hounds, Borsois, Bernese mountain dogs, Dobermans, Great Danes, Old English sheepdogs, mastiffs, pointers and Saint Bernards. Typically, cervical stenosis symptoms present at a young age in Great Danes, mastiffs and Bernese mountain dogs, with symptoms occurring later in other breeds. Anti-inflammatory drugs reduce inflammation and pressure on the spinal cord however, the recommended treatment course in most cases is surgery to repair or remove vertebra or disc material causing the compression.
- PetMD: Congenital Heart Defect (Pulmonic Stenosis) in Dogs
- University of Prince Edward Island: Pulmonic Stenosis
- American Kennel Club Canine Health Foundation: Aortic Stenosis
- Animal Emergency and Referral Associates: Subaortic Stenosis in Dogs
- PetMD: Narrowing of Vertebral Canal in Dogs
- VCA Animal Hospitals: Cervical Stenosis in Dogs
- Veterinary Surgical Centers: Wobbler Syndrome
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