Lab 12 Flashcards
Describe this lesion.
The apex of the heart is slightly rounded. On cut surface, the left ventricular wall is slightly thickended. Proximal to the aortic valve is a circumferential fibrotic ring. Distal to the aortic valve, the aorta is dilated. There is a slit-like ventricular septal defect in between the fibrous ring and aortic valve. The AV valves also contain sevveral small nodules
What is the blue arrow pointing to?
aortic valve
What is the red arrow pointing to?
a subaortic stenosis
Provide a morphological diagnosis for this lesion.
Aortic valve: chronic, focal, sub-aortic stenosis with post-stenotic aortic dilation. Left Ventricle: Chronic, diffuse, mild, concentric hypertrophy
A heart murmur (4/5) was heard in this puppy’s examination, how does that related to this lesion?
The aortic valve is situated on the left side of the canine. Turbulent blood flow through the aortic stenosis during systole causes vibration of the tissue creating the murmur
What is the primary pathologic change in this case?
subaortic stenosis
What is the secondary or compensatory change in this lesion?
concentric hypertrophy caused by pressure overload in the left ventricle as well as aortic ballooning
Is this case an example of systolic or diastolic dysfunction and why?
systolic, the subaortic stenosis obstructs the outflow of the left ventricle making it harder for the heart to pump the appropriate volume of blood out into the aorta
Describe this lesion.
The heart appeears enlarged, pericardial adipose tissue is reduced and largely replaced by clear, glistening, gelatinous material. There is a septal defect just ventral to the aortic and pulmonaru valves. The lumen of the left ventricle is dilated, and the left ventricular free wall is subjectively thin
What is the red circle?
a high ventricular septal defect
Provide a morphological diagnosis for this lesion.
Heart, ventricular septum: focal, chronic, high ventricular septal defect with left ventricular eccentric hypertrophy
What is the primary pathologic change in this case?
high ventricular septal defect
What are the compensatory changes in this lesion?
left to right shunting, volume overload causing eccentric hypertrophy of the left atrium and ventricle
How is the blood flow altered in this lesion?
the blood will be shunted from the left side to the right side of the heart
Is this case an example of systolic or diastolic dysfunction and why?
systolic dysfunction - during systole, the blood is forced from the left ventricle into the lower pressure right ventricle
Sometimes the blood flow disturbance in this lesion can undergo a reversal, how?
pulmonary hypertension from over perfusion of the lungs will increase pressure in the right ventricle causing the pressure to be greater than the left (blood flows from highest to lowest pressure)
Describe this lesion.
The patent ductus arteriousus connects the pulmonary trunk to the aorta. The right ventricular free wall is thickened to almost the same size as the left free ventricular wall
Provide a morphological diagnosis for this lesion.
Heart, aorta, and pulmonary trunk: chronic, focal, patent ductus arteriosus with concentric hypertrophy of the right ventricle
What is the function of the ductus arteriosus before birth?
it functions to shunt or byplass blood around the fetal lungs (becaise they are not functional and do not participate in gas exchange)
How is the blood flow altered in this lesion?
blood will flow from the left atrium to the right atrium causing a volume overload and eccentric hypertrophy which can lead to pulmonary hypertension
Describe this lesion.
The heart appears more rounded than normal with a poorly defined apex. The right ventricular free wall is flaccid. On cut surface both ventricles of the heart are moderately dilated. The aortic valve had multiple small white nodules on the surface of the valve. The left AV valve had multiple, small white nodules on the surface
Provide a morphological diagnosis for this lesion.
Heart, right and left side: chronic, diffuse, severe, dilated cardiomyopathy
What effect does this lesion have on blood flow through the heart?
systolic dysfunction - there is marked eccentric hypertrophy of the atria and ventricles
What could this lesion lead to?
biventricular congestive heart failure
What is the underlying cause of this lesion?
the cause for dilated cardiomyopathy is unknown
Describe this lesion.
Heart: on cut surface, the left ventricular free wall and septum are diffusely thickened. The lumen of the left ventricle is severely reduced. There are also multiple white foci on the pleural surface that penetrate into the pulmonary pleura
Provide a morphological diagnosis for this lesion.
Heart, left ventricle: chronic, diffuse, hypertrophic cardiomyopathy (concentric hypertrophy) with left atrial enlargement. Aorta and lungs: multifocal pulmonary and aortic mineralization
Is this case an example of systolic or diastolic dysfunction and why?
primarily a diastolic dysfunction however there are systolic dysfunction components
Many cats that have this cardiac lesion will present with painful, cold, and paretic hindlimbs. Why is that?
Thrombi form due to the stagnation of blood and leave the left atrium and can get wedged at the bifurcation of the abdominal aorta preventing blood flow to the limbs
Describe this lesion.
Enlarged right ventricule and compacted with heart worms that extend up into the pulmonary arteries. There is a mottled tan to red friable material covering the nemotodes. The pulmonary arteries are slightly distended. There are multiple, white round foci on the pleural sirface
Provide a morphological diagnosis for this lesion.
Heart, right ventricle: chronic, focal, concentric hypertrophy with intralesional nematode parasites. Lungs: chronic, multifocal, pale white foci
What disease causes this lesion?
heartworm - dirofilaria immitis
What is cor pulmonale?
enlargement and failure of the right-side of the heart as a result of pulmonary hypertension causing concentric hypertrophy, ascites, hepatic congestion, hydrothorax, and peripheral edema
How is cor pulmonale play into the pathogenesis of heartworm?
The presence of the worm in the vasculature is irritating and results in proliferation of the tunica intima, vascular sclerosis, and vascular fibrosis of the pulmonary vessels. Fibrosis of the pulmonary vasculature result in pulmonary hypertension. Pulmonary hypertension and the physical presence of the nematodes in the pulmonary vasculature can increase the pressure load on the right side of the heart which will lead to right side heart failure
Describe this lesion.
the subpericardium is characterized by multifocal to coalescing areas of hemorrhage. There are widely disseminated streaks of myocardial pallor. On cut surface, the area of hemorrhage and pallow penetrate into the myocardium
Histology revealed swollen, fragmented, hypereosinophilic degenerate and necrotic cardiomyocytes. Provide a morphologic diagnosis considering both the histology and gross findings.
Heart: myocardial necrosis and hemorrhage, acute, multifocal to widely disseminated
What is the common name for this lesion?
mulberry heart disease
What is a likely etiology for these lesions and the cause of death in this animal?
Vitamin E or selenium deficiency is thought to cause this. Necrosis of the vasculature results in hemorrhage and thrombus formation. Thrombus formation in small vessels can result in infarction and necrosis
