Acquired Valvular Diseases Flashcards
Acquired Valvular Diseases
Chronic Mitral Valve Insufficiency Degenerative Mitral Valve Disease Mitral Valve insufficiency Tricuspid Valve Insufficiency Endocardiosis vs Endocarditis
What is the most commonly encountered cardiovascular disorder in dogs?
Chronic Mitral valve insufficiency
75% of dogs 16 years or older are affected
Is chronic mitral valve insufficiency a progressive disease?
Yes
What is the cause of 95% of all cases of congestive heart failure in small breed dogs?
Chronic mitral valve insufficiency
What is chronic mitral valve insufficiency?
A lesion that consists of proliferation of fibroblastic connective tissue within the valve leaflets leads to decrease function
What is degenerative mitral valve disease?
The stiff malformed leaflets fail to close
The chordae tendinae stretch and rupture
Left atrium dilates
What does the dilation of the left atrium lead to?
It compresses the left mainstream bronchus producing coughing and dyspnea
What happens during systole of patients with degenerative mitral valve disease?
The blood flows back through the mitral valve and the left atrium dilates
What else is degenerative mitral valve disease known as?
Endocardiosis
Valvular regurgitation
Valvular insufficiency
Chronic valve disease
What is the most commonly affected valve in dogs and cats?
Mitral valve aka the left atrioventricular valve
What other name is mitral valve insufficiency known as?
Myxomatous mitral valve disease (MMVD)
What are the clinical signs of mitral valve disease (MMVD)
Older small or toy breed dogs
Cough
Dyspnea or tachypnea
Decreased appetite
What does the cough of a patient with MMVD sound like?
Deep
Resonant
Worse with exercise or at night
What does the heart murmur of a patient with mitral valve disease sound like?
Systolic murmur
Left apex
What do the radiographs of a patient with mitral valve insufficiency with pulmonary edema look like?
Venous engorgement
Alveolar densities or air bronchograms
What do the radiographs of a patient with mitral valve insufficiency without pulmonary edema look like?
Left atrial and ventricular enlargement
Elevation of the thoracic trachea
Loss of the cardiac waste
Enlarged left auricle
What does the echocardiogram of a patient with mitral valve insufficiency look like?
Increased diameter of the left atrium and ventricle
Marked reduction in the left ventricular contractility
Mitral valve leaflets may be thickened for prolapsing
How do you treat mitral valve insufficiency?
Diuretics Arterial dilators \+/- Digoxin ACE inhibitors Cough suppressants Pimobendan Diet
Diuretics
Furosemide
Reduce the circulatory volume on the left side of the heart
Arterial dilators
Hydrazaline, Enalapril
Decrease systemic vascular resistance so the heart does not have to work as hard
Digoxin
Decrease the heart rate to less than 160 beats/min in small dogs
ACE inhibitors
Angiotensin-converting enzyme inhibitors
Enalapril and benazapril
Diet
Maintains good body condition
Low in sodium will decrease fluid load in the patients
What is the second most commonly affected valve in dogs and cats?
The tricuspid valve (right atrioventricular valve)
What are the clinical signs of tricuspid valve insufficiency?
Similar to right-sided heart failure
Pleural effusion
Abdominal distension
Hepatomegaly
What is the treatment of tricuspid valve insufficiency?
Same as mitral valve insufficiency
Repeated therapeutic abdominocentesis is required
What could develop in tricuspid valve insufficiency as the right atrium dilates?
Atrial fibrillation
Endocarditis
Caused by bacterial infections of the heart
