Pulmonic Stenosis In Dogs
This is a condition that causes blockage to the blood flow from the right ventricle. The major reason for this is usually abnormal growth of the flaps on the valves connecting the right ventricle and the pulmonary artery. On the other hand, the stenosis can also arise in the region outside the pulmonary valve, or the sub-valvular region i.e. within the outflow path of the right ventricle.
The right ventricle has to produce great amount of pressure during contraction to surmount the stenosis. In modest to extreme cases, the increased pressure can cause extreme swelling of the right ventricle with thickening of the muscle fibres. As these muscle fibres thicken, the capacity of the ventricle to perform its normal functions is reduced, leading to a rise in right atrial pressure and obstruction in the veins. The rapid rate of blood flow results in an enlarged artery, with right-sided congestive failure being reported in severe cases.
An inability to flourish and even exercise intolerance are some of the symptoms of dogs with pulmonic stenosis, coupled with accumulation of fluid in the abdomen or limbs. A loud murmur and a distended and pulsating jugular vein can also be heard, all of which can be diagnosed using electrocardiography, x-rays, and echocardiography. Doppler echo-cardiography can be quite useful in evaluating the severity of the stenosis.
Surgery may result in remarkable improvement in dogs with modest or severe pulmonic stenosis. Whatever surgical procedure the veterinarian settles on is dependent on the presence and extent of thickening of the muscle fibres underneath the valve. Right-sided congestive heart failure, once detected, should be combated using drugs such as diuretics and vasodilators (drugs that expand blood vessels). Atrial fibrillation and right-sided congestive heart failure are very bad conditions for your dog, if detected. In the case of atrial fibrillation, your veterinarian may recommend digitalis to manage the arrhythmia.
Aortic Stenosis In Dogs
Blood flowing from the left ventricle might be blocked in a number of ways. A ridge of fibrous tissue situated inside the outflow tract of the left ventricle can diminish flow. This is known as sub aortic stenosis. In other situations, the impediment could be within the valve leading out of the left ventricle (valvular stenosis) or still past the aortic valve (supravalvular stenosis). In dog, Boxers, Golden Retriever, Rottweiler, German shepherd, and Newfoundland breeds were the most affected by supravalvular stenosis occurred most frequently in.
Aortic stenosis leads to thickening of the muscle fibres of the left ventricle. The formation of areas of poor blood flow throughout the heart is a key consequence of this thickening of the muscle fibres. When the blood supply to the cardiac muscle drops, the heart is denied adequate oxygen and is incapable of elimination of carbon dioxide and other cellular waste products. Such a situation contributes immensely to the progression of life-threatening ventricular rhythm problems.
In a number of cases of aortic stenosis, there could be a past record of loss of consciousness as a result of blood flow deficit to the brain and trouble with ordinary levels of exercise. In other cases, animals without history of disease may die unexpectedly, with the defect being detected only when it’s too late. If there is suspicion of stenosis, electrocardiography can be used by the veterinarian to check the electrical activity of the heart. Where a dog faints regularly or shows other symptoms of likely heart rhythm irregularities, the veterinarian may observe heart activity throughout the day. Tests such as x-rays or ultrasonography can also be useful.
Your veterinarian should be able to establish the most suitable course of treatment for your dog. Treatment options available could be drugs to decrease problems related to exercise intolerance or loss of consciousness. Surgery, though beneficial, is expensive to perform and quite risky. Slightly affected dogs frequently don’t need any treatment, with the outlook being good. Dogs suffering from aortic stenosis should never be used for breeding.
Persistent Right Aortic Arch
This is a congenital abnormality in which the right aortic arch passes at the rear of the oesophagus. This puts pressure on the oesophagus and constricts it close to the heart. Persistent right aortic arch is prevalent in horses, cats, and dogs; German Shepherds and Irish Setters are the most prone to abnormality than other breeds.