Pathomorph. II - cardiovascular pathology Flashcards
Cardiac activity is regulated is regulated by: (2)
nodal tissue
sympathetic nervous system
(- orthosympathic (adrenergic)
—–> increases
- parasympathic (cholinergic)
—–> decreases)
broad categories for pathologies found during necropsy (4)
congenital
non-inflammatory
inflammatory
neoplastic
name a well known Congenital cardiovascular malformation
persistent right aortic arch or PRAA
interatrial communication (Botal hole)
interventricular communications
What is a complex heart malformation?
Result of at least two single myocardial abnormalities.
Define FALLOT’S TRILOGY
Trilogy of Fallot is a combination of congenital heart defects consisting of three key features including:
atrial sepral defects,
pulmonary stenosis, and
ventricular concentric hypertrophy.
Define Fallot’s tetralogy
Tetralogy of Fallot describes a combination of heart defects made up of the following four:
ventricular septal defect/interventricular communication,
overriding aorta/aortic dextroposition
(right position deviation),
pulmonary stenosis and
ventricular concentric hypertrophy.
Define serous pericarditis.
In most instances, it is caused by viral infection. The clear serous fluid must be distinguished from a transudate, which typically accumulates in the pericardial sac in heart failure or anasarca.
Define serofibrinous pericarditis.
The inflammatory process is characterized by the accumulation of fibrinous and serofibrinous exudate in the pericardial sac.
The inciting agent causes acute fibrinous or serofibrinous pericarditis which heals by formation of granulation tissue that contracts over time.
There is non-specific inflammation, fibrin deposition with organization, fibrosis and calcification with obliteration of the pericardial cavity.
Define fibrinous pericarditis (cor villosum)
Acute fibrinous pericarditis occurs when the inflamed pericardium is covered with a layer of material called fibrin.
In fibrinous pericarditis, the pericardial texture is rough, granular, and has many fibrous adhesions.
Fibrinous pericarditis is usually caused by trauma, surgery, acute myocardial infarction, uremia, collagen vascular disorders, and malignancies.
Define purulent pericarditis
Acute purulent pericarditis occurs when the pericardium is infected and covered with a thick pus.
Purulent pericarditis is defined as a localized infection of the pericardial space characterized by gross pus in the pericardium or microscopic purulence (>20 leukocytes per oil immersion field).
Name 2 nutritional myopathies to cause myocardic necrotic lesions in bovine.
vitamin E & selenium deficiencies
toxic myocardic necrosis can be caused by what in the horse & pig?
in ruminants?
in dogs?
horse & pig (Monensin, avian anticoccidial drug)
other: Thallium (toxic metallic element), fluoroacetates -
mainly dogs and ruminants
associated with chemotherapy in dogs (rubidomycine, doxorubicine…..)
What types of hypertrophy is seen at the far left and far right?
Far left: eccentric hypertrophy with dilation
Far right: concentric hypertrophy
(Middle: normal)
Myocardic adaptation to increase in volume?
Increase of myocardic mass + widening of ventricular cavity = eccentric hypertrophy.
Myocardiocytes stretch.
Name 2 potential causes of eccentric hypertrophy.
atrio-ventricular insufficiency
valvular insufficiency
(heart disease/failure)
Myocardic adaptation to increase in pressure?
Increase of myocardic mass with reduction of ventricular cavity = concentric hypertrophy.
Myocardiocytes widen.
Name 2 potential causes of concentric hypertrophy.
Renal or extrarenal origin Chronic Hypertension
Sigmoid stenosis
(The base of the ventricular septum may bulge prominently into the outflow tract of the left ventricle. Such hearts have been referred to as having a sigmoid ventricular septum. )
lung sclerosis & emphysema
focal endocardial sclerosis can be a consequence of what cardiac pathology?
a conseuqence of mitral insufficiency
From a functional point of view, cardiac atrophy is followed
by
signs of decompensation of the cardiac insufficiency with apparition of extracardiac lesions such as,
abdominal effusion, cardiac liver, peripheral edemas, “cardiac lung”
decompensation can be divided into quick/acute and progressive/chronic
congenital cardiomyopatheis (idiopathic) can be divided categorically into: (3)
hypertrophic
dilated (with contractility reduction)
restrictive (characterised by endocardic fibrosis)
Name 3 non idiopathic cardiomyopathies.
- cardiothyreosis/ thyrotoxic heart disease (dog & cat)
- taurine deficiency (cat)
- turkey cardiac hypertophy (round heart disease) result of stress or Sodium chloride or Furazolidone intoxications
Congenital dilated cardiomyopathy can be characterized by (3)
bilateral cavity dilatation,
normal or reduced LV wall and septum,
moderate L atrial dilatation
Congenital hypertrophic cardiomyopathy can be characterized by (3)
LV wall and septum hypertrophy,
LV cavity reduction,
bilateral atrial dilatation
Congenital restrictive cardiomyopathy can be characterized by (4)
LV wall and septum hypertrophy,
LV cavity reduction,
L atrial dilatation,
Endocardic fibroelastosis
Define myxoma.
is a myxoid tumor of primitive connective tissue typically found in the heart.
can be as small as a few mm or up to a few cm.
Congestive endocarditis
when endocarditis leaads to congestive heart failure due to structural degenerations
superficial endocarditis
infection of the endocardial surface of the heart. It usually involves heart valves
thrombotic endocarditis
the presence of vegetations on cardiac valves, which consist of fibrin and platelet aggregates and are typically nonbacterial so devoid of inflammation or bacteria.
verminous aneurysms
a special type of aneurysm observed in horses, caused by intra-vascular migration of a worm, the Strongylus vulgaris. It has been named verminous aneurysm and generally involves the mesenteric arteries.
panarteritis
Inflammation involving all the layers of an artery.
in bovine, associated with malignant catarrhal fever
Chronic fibrotic lymphangitis
Chronic inflammatory lesions with thickening of lymphatic vessels walls by fibrosis
what are chemodectoms
chemoreceptor tumors
rare tumor of the neuroendocrinne tissue of the carotid body
Benign and malignant forms exist - consequences also resulting of cardiac localisation
an accumulation of whole blood in the pericardial sac.
Hemopericardium
Death often occurs unexpectedly from cardiac tamponade, meaning compression of the heart caused by the accumulation of blood in the pericardial sac leading to reduced cardiac output and poor perfusion of vascular beds in all organ systems.
On clinical examination, heart sounds are muffled.
the accumulation of clear, light yellow, watery, serous fluid (i.e., transudate) in the pericardial sac.
hydropericardium
A few fibrin strands can be present and the fluid could clot after exposure to air.
hydropericardium can occur in animals with (name the 3 conditions)
(1) hypoproteinemia (decreased colloid osmotic pressure) caused by liver disease or protein-losing nephropathy/enteropathy,
(2) heart failure (increased hydrostatic pressure) where there is poor venous return to the heart, and
(3) vascular injury, where damage to the barrier function of the vascular wall can result in leakage of small quantities of plasma proteins.
gross appearance of hydropericardium
The pericardial surfaces are smooth and glistening in acute cases,
but in chronic cases, the epicardium becomes opaque because of mild fibrous thickening and can appear roughened and granular when there is villous proliferation of fibrous tissue, especially over the atria.
gray gelatinous appearance of epicardial fat deposits indicates?
Serous atrophy of fat
Healthy animals normally have abundant white or yellow epicardial fat deposits.
Serous atrophy microscopically
refers to Serous atrophy of (e.g. epicardial) fat,
Microscopically, lipocytes are atrophic and edema is present in the interstitial tissue.
Why does Serous atrophy of epicardial fat occur?
Serous atrophy of epicardial fat occurs rapidly during anorexia, starvation, or cachexia because fat is catabolized to maintain energy balance.
The pericardium responds to excess fluid in the pericardial space by
dilation.
However, this outcome requires adequate time to allow adjustments in size.
Pericarditis grossly
Grossly, both the visceral and parietal pericardial surfaces are covered by variable amounts of yellow fibrin deposits, which can result in adherence between the parietal and visceral layers.
When the pericardial sac is opened the attachments are torn away (so called bread-and-butter heart).
Pericarditis microscopically
Microscopically, an eosinophilic layer of fibrin with admixed neutrophils lies over a congested epicardium.
The outcome of fibrinous pericarditis varies. Describe.
Early death is frequent because many of these lesions result from infection by highly virulent bacteria and concurrent septicemia.
When survival is prolonged, adhesions form between the pericardial surfaces after fibrous organization of the exudate.
Suppurative pericarditis is seen mainly in
cattle as a complication of traumatic reticuloperitonitis (“hardware disease”).
Foreign bodies, such as nails or pieces of wire that accumulate in the reticulum, occasionally penetrate the reticular wall and diaphragm, enter the adjacent pericardial sac, and introduce infection.
Some affected cattle survive for weeks to months until death ensues from congestive heart failure or septicemia.
Suppurative pericarditis grossly
Grossly, the pericardial surfaces are notably thickened by white, often rough, shaggy-appearing masses of fibrous connective tissue that enclose an accumulation of white to gray, thick, foul-smelling, purulent exudate.
Constrictive pericarditis is
a chronic inflammatory lesion of the pericardium accompanied by extensive fibrous proliferation and eventual formation of fibrous adhesions between the surfaces of the visceral and parietal pericardium.
Severe lesions obliterate the pericardial sac and constrict the heart with fibrous tissue and can interfere with cardiac filling and thus cardiac output.
The condition is seen in some cases of suppurative pericarditis in cattle and pigs with chronic fibrinous pericarditis.
Hypertrophy of the myocardium represents an increase in muscle mass, which is the result of
an increase in the size of cardiac muscle cells.
Hypertrophy is generally secondary and is the result of a compensatory response to increased workload; it is usually reversible on removal of the cause.
primary hypertrophy also occurs, as in cats and dogs with
idiopathic hypertrophic cardiomyopathy, and is not reversible.
Two anatomic forms of hypertrophy are recognized.
Eccentric hypertrophy results in a heart with enlarged ventricular chambers and walls of normal to somewhat decreased thickness.
Concentric hypertrophy results in the heart characterized by small ventricular chambers and thick walls.
Eccentric hypertrophy results in a heart with
enlarged ventricular chambers and walls of normal to somewhat decreased thickness;
it is produced by lesions that increase blood volume load such as valvular insufficiencies and septal defects.
The concentric hypertrophy the heart is characterized by
small ventricular chambers and thick walls;
it results from lesions that increase pressure load such as valvular stenosis, systemic hypertension, and pulmonary disease.
Three stages of myocardial hypertrophy are recognizable:
(1) initiation,
(2) stable hyperfunction, and
(3) deterioration of function associated with degeneration of hypertrophied myocytes.
Microscopically, in myocardial hypertrophy, the myocytes are enlarged and have large nuclei.
Right ventricular hypertrophy is structurally or functionally caused by
pulmonary stenosis or pulmonary hypertension, respectively.
(e.g. congenital pulmonic stenosis in dogs and cats.)
Examples of pathology that can cause pulmonary hypertension and via that route, right ventricular hypertrophy.
dirofilariasis in dogs and cats,
“brisket disease” (“high-altitude disease”) in cattle,
and chronic alveolar emphysema (“heaves”) in horses.
define caval syndrome
is a life-threatening illness caused by a mass of heartworms located aberrantly in the right atrium, the ventricle, and often the vena cava.
The worm mass interferes with closure of the tricuspid valve and impedes normal flow of blood through the right heart, leading to cardiovascular collapse.
Without proper therapy, death can occur 1 to 2 days after onset of clinical signs.
dogs with congenital subaortic stenosis,
cats with hyperthyroidism, and
dogs and cats with systemic hypertension, may all develop what?
Left ventricular hypertrophy
define Pheochromocytoma
Pheochromocytoma is a type of neuroendocrine tumor that grows from cells called chromaffin cells.
common clinical sign is hypertension
Biventricular hypertrophy can occur with
hypertrophic cardiomyopathy and various congenital cardiac anomalies.
Eccentric hypertrophy develops in the late stages of diseases that initially cause concentric hypertrophy as cardiac dilation is superimposed.
Hydropic degeneration
also known as cell swelling, is a term used to express the swelling that occurs in injured cells by an influx of water/ vacuolization with distention of cellular elements.
Myocarditis generally is the result of infections spread in what way?
hematogenously
occurs in various systemic diseases.
Types of inflammation provoked by infectious agents that produce myocarditis include
suppurative, necrotizing, hemorrhagic, lymphocytic, and eosinophilic.
Suppurative myocarditis results from
localization of pyogenic bacteria in the myocardium that are trapped in thromboemboli originating from vegetative valvular endocarditis on the mitral and aortic valves.
The sequelae to myocarditis include what 3 options?
(1) complete resolution of lesions,
(2) scattered residual myocardial scars, or
(3) progressive myocardial damage with acute or, in some cases, chronic cardiac failure as secondary dilated (congestive) cardiomyopathy.
Endocardial hemorrhages are commonly seen and may be the result of (2)
trauma or septicemias, especially those with endotoxins, or can occur agonally at death.
Endocarditis is usually the result of ?
except for?
is usually the result of bacterial infections,
except for lesions produced by migrating Strongylus vulgaris larvae in horses and rarely in mycotic infections.
Vegetative valvular endocarditis grossly
the affected valves have large, adhering, friable, yellow-to-gray masses of fibrin termed vegetations, which can occlude the valvular orifice.
In chronic lesions, the fibrin deposits are organized by fibrous connective tissue to produce irregular nodular masses termed verrucae (wartlike lesions).
the components of Virchow’ striad in thrombogenesis
endothelial injury, turbulence, and hypercoagulability
whats bigger than ecchymoses?
suffusions
A distinctive example of a specific disease with cardiac hemorrhage is
mulberry heart disease, associated with vitamin E-selenium deficiency in growing pigs.
In these pigs, hydropericardium accompanies severe myocardial hemorrhage that results in a red, mottled (mulberry-like) appearance of the heart.
An aneurysm is
a localized dilation or outpouching of a thinned and weakened portion of a vessel.
Usually, arteries are affected, especially large elastic arteries, but the lesion can also occur in veins.
difference between Arteriosclerosis & atherosclerosis
Arteriosclerosis is characterized by intimal fibrosis of large elastic arteries,
atherosclerosis is characterized by intimal and medial lipid deposits in elastic and muscular arteries (atheroma).
Arteriosclerosis is an
age-related disease that occurs frequently in many animal species but rarely causes clinical signs.
The disease develops as chronic degenerative and proliferative responses in the arterial wall and results in loss of elasticity (“hardening of the arteries”) and less often luminal narrowing.
Grossly, the lesions are seen as slightly raised, firm, white plaques.
define angiitis (no typo, really has that many ‘i’s)
inflammation of blood vessels, a term that includes all blood and lymphatic vessels.
in contrast to arteritis which is only arteries.
synonym for angitis is vasculitis
Arteritis and vasculitis can develop from
endothelial injury caused by either infectious agents or immune-mediated mechanisms or may be caused by local extension of suppurative and necrotizing inflammatory processes in adjacent tissues.
Arteritis is a prominent feature of several parasitic diseases.
Systemic infections with phlebitis as a lesion include (2)
salmonellosis in several species and feline infectious peritonitis.
Lymphangitis may be acute, subacute, granulomatous, or chronic resulting in
lymphedema.
