They are congenital malformations that may arise from lesions of hypoplasia, thickening of valvular leaflets or the presence of fibrous rings.
They disturb the outflow of blood from the ventricles to the pulmonary and aortic arteries.
They cause narrowing of the valve resulting in overload of the ventricle corresponding to the hypertrophy of the same.
They are congenital and hereditary.
Affected animals may be asymptomatic, have mild symptoms (eg tiredness or cough after exercise), or have severe symptoms (episodes of syncope or exercise intolerance).
By Doppler cardiac ultrasonography, which allows to evaluate the morphology of the valves and the flow of blood through them, as well as the speed of passage.
CLASSIFICATION OF STENOSES (or their absence) - Germany Boxer Clube.
Aortic stenosis:
Degree 0 -free (values up to 2.0 m / s).
Grade 1-Transition form (values> 2.0 <2.25 m / s).
Grade 2-Light Form (between 2.25 <3.5 m / s).
Grade 3 - Medium Form (3.5 to 4.5m / s).
Grade 4-Severe Form (> 4.5m / s).
Lung Stenosis:
Degree 0 - Free (values up to 1,8m / s).
Degree 1 - Transition form (values> 1.8 and <2.25 m / s).
Grade 2 - Light Form (2.25 and <3.35 m / s).
Grade 3 - Medium Form (from 3.5 to 4.5 m / s).
Grade 4 - Severe Form (> 4.5 m / s).
Correct name is ARRITMOGENIC CARDIOMYOPATHY.
Boxer's cardiomyopathy is a primary myocardial disorder
characterized by slow and progressive myocardial
degeneration.
Initially there is a dysfunction in electrical
conduction that causes arrhythmias, syncope or sudden
death.
A wide variety of clinical signs can be observed, but
most are classified into three categories.
Asymptomatic dogs, but with cardiac arrhythmia.
Dogs with episodes of weakness or syncope.
Dogs with signs of congestive heart failure.
Family disease inherited as an autosomal dominant trait
with variable penetrance.
Studies aimed at integrating the genetic basis of the
CAVD into the dog are rapidly developing, since the
canine genome and the genetic mutations responsible for
CAVD in humans have already been identified.
Definitive diagnosis: Holter test
Due to the fact that they are hereditary pathologies, and in very early initial stages, they are asymptomatic, it is essential to carry out screenings on all specimens destined for reproduction.
Source: Boxer Club of Portugal website.