Test 2: lecture 1 heart Flashcards
3 functions of circulatory system
circulation
thermoregulation
fluid homeostasis
what valve in right side of heart
tricuspid and pulmonary
what valve in left side of heart
mitral and aortic
layers of the heart
endocardium
myocardium
pericardium
—- mechanisms operate to help maintain
adequate cardiac output & tissue perfusion
Compensatory
dilation of the heart cause
increase in chamber volume
hypertrophy of the heart
increase in mass of heart, cells get bigger
ischemia
decrease in blood flow to tissues
congestion in heart leads to
pooling of blood behind the failing chambers, leads to increased hydrostatic pressure and edema
Chronic hepatic
congestion (“nutmeg liver”), Ascites and subcutaneous edema are symptoms of —
right sided heart failure
left sided heart failure symptoms
pulmonary congestion and edema
right and left sided heart failure symptoms
hydrothorax
fluid build up in abdomen
ascites
cardiac myocytes look
central nuclei
intercalated discs
cross striations
___ hypertrophy due to ↑ workload; REVERSIBLE if underlying cause is removed
SECONDARY
— hypertrophy is usually irreversible
PRIMARY
concentric cardiac hypertrophy causes
increased wall thickness
decreased chamber volume
parallel myocytes are added in response to increased pressure
—- hypertrophy is caused by increased pressure overload
concentric
— myocardial hypertrophy is caused by volume overload
eccentric
myocytes in series
eccentric myocardial hypertrophy will cause the wall and volume to —
increased chamber volume (dilation)
normal or decreased wall thickness
primary vs secondary cardiomyopathy
primary- caused by genetics or unknown cause
secondary- caused by something other than genetics
3 types of cardiomyopathy
HYPERTROPHIC
DILATED
RESTRICTIVE
HCM is caused by — in maine coons and ragdoll
MYBPC3 gene
young male cats
primary cardiomopathy
cause cardiomegaly and concentric hypertrophy
Thick LV wall, ↓ LV volume, LA dilation, thrombosis
HCM cause what gross findings
Thick LV wall, ↓ LV volume
LA dilation, thrombosis,
enlarged heart- cardiomegaly
Hypertrophic cardiomyopathy
what has similar gross findings to HCM
thyrotoxic cardiomegaly
Thyroid gland hyperplasia → ↑ thyroid hormone production → ↑ production of myocardial contractile proteins → myocardial hypertrophy
can be reversible
Hypertrophic cardiomyopathy
primary dilated cardiomyopathy effects
humans, dogs (dobermans, young portuguese water dogs), cattle
caused by genetics
enlarged rounded heart, dilated chambers with thin walls- eccentric hypertrophy
gross findings of dilated cardiomyopathy
Enlarged rounded heart
- Dilated chambers, thin walls (eccentric hypertrophy)
gross findings of thyrotoxic cardiomegaly
same of HCM, but reversible if you fix the hyperthyroidism
enlarged heart, thick LV wall, decreased LV volume (concentric hypertrophy), LA dilation and thrombosis
taurine deficiency will cause what heart problem
secondary dilated cardiomyopathy
big round heart, dilated chambers, thin walls (eccentric hypertrophy)
boxer dog cardiomyopathy
Arrhythmogenic right ventricular cardiomyopathy (ARVC)
variant of DCM
heart cells replaced by fibrous or fat
leads to dilated RV
Predisposed to ventricular arrhythmias, syncope, heart failure, sudden death
symptoms of ARVC
Arrhythmogenic right ventricular cardiomyopathy
variant of DCM - boxer dog cardiomyopathy
arrhythmias, syncope, heart failure, sudden death
RV myocytes replaced by adipose tissue (or fibroadipose tissue)
* RV normal or dilated (common)
Restrictive cardiomyopathy will impair —
ventricular filling
ventricles not as stretchy- fibrosis, ↑ moderator bands, fibroelastosis
feline LVEF is caused by
Sequela of ENDOMYOCARDITIS
(idiopathic inflammation that often follows a stressful event)
Thick opaque endocardium
(usually involving LVOT)
Feline left ventricular endocardial fibrosis
variant of RCM- restrictive
gross findings of Feline left ventricular endocardial fibrosis
Thick opaque endocardium
(usually involving LVOT)
variant of RCM- restrictive
excessive moderator bands
form of restrictive cardiomyopathy
Endothelial-lined bands of
Purkinje fibers & collagen (“false tendons”) traverse the LV & restrict ventricular filling
- Congenital defect that
manifests later in life
excessive moderator bands will cause
restricted ventricular filling
hypertrophic vs dilated vs restrictive cardiomyopathy
cardiomyopathy can cause
arrhythmia
thrombosis
congestive heart failure
what happens when heart muscle injured
can’t regenerate
will go through necrosis and form fibrosis
Myocardial pallor, dry, gritty texture
(dystrophic mineralization)
fibrosis- firm depressed myocardial scar in chronic stage
sheep
nutritional myopathy from vitamin E or selenium deficiency
white muscle disease, mulberry heart disease in pigs
leads to decreased antioxidant activity and myocyte necrosis
will cause mineralization
white muscle disease in — and mulberry heart disease in — is caused by —
ruminants
pigs
nutritional myopathy from vitamin E or selenium deficiency
inflammation of the myocardium
myocarditis
similar in appearance to necrosis
Granulomatous myocarditis in a dog Aspergillus terreus fungi infection
Suppurative myocarditis in a cow - chronic abcsess
Histophilus somni infection
endocardiosis definition
Idiopathic degeneration of valvular collagen
Mitral > tricuspid >aortic & pulmonic
endocardiosis gross findings
thickened/nodular valve margins (smooth, glistening, & opaque)
Idiopathic degeneration of valvular collagen
— will commonly get endocardiosis
Cavalier King Charles spaniel
old small breed dogs
what valves are normally attacked by endocardiosis
Mitral > tricuspid > aortic & pulmonic
Idiopathic degeneration of valvular collagen in old small breed dogs such as Cavalier King Charles spaniel
— valvular degeneration comprised of loose fibroblastic tissue with —
Myxomatous valvular degeneration comprised of loose fibroblastic tissue with mucopolysaccharides; non-inflammatory!
Myxomatous valvular degeneration cause
loose fibroblastic tissue with mucopolysaccharides; non-inflammatory!
type of endocardiosis on valves of heart
valve insufficiency cause — of blood
regurgitation
symptoms of valvular insufficiency
— (turbulent flow)
Atrial volume overload → — and CHF
Atrial subendocardial fibrosis = —
— THROMBOSIS → thromboembolism and infarcts
— RUPTURE
— RUPTURE → hemopericardium
HEART MURMUR
ECCENTRIC HYPERTROPHY
“JET LESION”
ATRIAL
corda tendinea
ATRIAL
Atrial subendocardial fibrosis are also called
jet lesions
Atrial jet lesion (subendocardial fibrosis) where regurgitant jet strikes atrial wall
atrial volume overload will cause — hypertrophy
eccentric
Atrial thrombosis (top) & chorda tendinea rupture (bottom)
endocardiosis or endocarditis have inflammation
endocarditis- inflammation of endocardium
endocardiosis- is degeneration of valves
endocarditis is usually caused by
bacterial; rarely fungal or
parasitic
endocarditis effect — valve in cattle and — valve in other species
tricuspid
mitral
endocarditis
Gross findings: thrombi (“vegetations”) on valvular/mural endocardium
gross findings of endocarditis
thrombi (“vegetations”) on valvular/mural endocardium
Vegetative endocarditis morphology
Septic thrombi composed of fibrin, bacteria, neutrophils granulation tissue/fibrosis
— composed of fibrin, bacteria, neutrophils and granulation tissue/fibrosis form on valves with endocarditis
Septic thrombi
how does vegetative endocarditis form
bacteria from somewhere in the body will clump onto minor endocardial damage at valves and cause inflammation
can break off and cause thrombosis
thrombosis is caused by what three things
virchow’s triad
vegetative endocarditis will cause —
VALVULAR INSUFFICIENCY (leading to CHF) or effects of BACTEREMIA
SEPTIC THROMBOEMBOLI
ISCHEMIA & INFARCTS
INFECTION & INFLAMMATION
dystrophic mineralization
necrotic tissue that forms mineralization
metastatic mineralization is caused by
too much calcium in the body
endocardial mineralization gross findings
gritty white plaques on
endocardium (+/- vascular endothelium)
vitamin D toxicosis can be caused by
oversupplementation, ingestion of cholecalciferol rodenticides or calcinogenic plants containing vitamin D analogs
will cause endocardial mineralization
three causes of endocardial mineralization
vitamin D toxicosis
johne’s disease
uremia
pericardium is made of the — and —
Visceral layer = EPICARDIUM (outermost layer of heart)
Parietal layer associated with outer fibrous portion of
PERICARDIAL SAC
serous fluid in pericardial cavity is called
HYDROPERICARDIUM
blood in pericardial cavity is called
HEMOPERICARDIUM
inflammatory of the pericardial cavity is called
pericarditis
rapid fluid accumulation in the pericardial cavity cause
CARDIAC TAMPONADE
cardiac tamponade is the — of the heart due to —
compression
increased pressure in pericardial cavity
cardiac tamponade can lead to — and death if not corrected
cardiogenic shock
Interferes with cardiac filling, causing venous blood to pool in the splanchnic & systemic vasculature
three routes of pathogen entry for pericarditis
inflammation of the pericardium
HEMATOGENOUS spread (e.g., septicemia)
DIRECT PENETRATION (e.g., “hardware disease”)
LOCAL EXTENSION from myocardium, pleural cavity, mediastinum
Acute fibrinous pericarditis (fibrin easily removed from surface)
Chronic pericarditis (firm fibrous adhesions between pericardial layers)
Serous atrophy of pericardial fat
Thin translucent gelatinous adipose tissue
emaciation
the state of being excessively thin and wasted.
wasting also called
cachexia
serous atrophy of pericardial fat gross findings
Thin translucent gelatinous adipose tissue
Blood is shunted from— (HIGH pressure to LOW pressure)
LEFT to RIGHT
ductus arteriosus
skips fetal lungs
pulmonary artery to aorta
foramen ovale
hole from left to right side of heart in fetus- skip lungs
Reversal of flow (RIGHT to LEFT) may occur later in disease due to —
pulmonary hypertension
(normal flow left to right- leads to build up in the lungs)
patent ductus arteriosus (PDA)
cause lung overload
ventricular septal defect (VSD)
pulmonic stenosis will cause —
Pressure overload→ concentric RV hypertrophy
aortic stenosis will cause —
Pressure overload → concentric LV hypertrophy
mitral or tricuspid valve dysplasia will cause
regurgitation
atrial volume overload & eccentric hypertrophy
left side of heart
subaortic stenosis
Raised fibrous ring below aortic valve that narrows the LVOT→ LV pressure overload & concentric hypertrophy
subaortic stenosis will cause — hypertrophy
concentric
Raised fibrous ring below aortic valve that narrows the LVOT →LV pressure overload & concentric hypertrophy
Malformed valve leaflets with short chordae tendineae or direct insertion of valve margin onto papillary muscle → valvular insufficiency → —overload & — hypertrophy
atrial volume
eccentric
persistent right aortic arch (PRAA)
Vascular ring formed around esophagus and trachea → proximal megaesophagus (sequelae: regurgitation, aspiration pneumonia)
persistent right aortic arch will lead to
Vascular ring formed around esophagus and trachea → proximal megaesophagus (sequelae: regurgitation, aspiration pneumonia)
— is anomaly with single blood vessel from RV & LV
Persistent truncus arteriosus
Ectopia cordis
heart outside thoracic cavity)
Peritoneal-pericardial diaphragmatic hernia
(liver/intestine
translocated into pericardial cavity; may be subclinical
4 lesions of Tetralogy of Fallot
- Pulmonic stenosis
- Ventricular septal defect
- RV hypertrophy (secondary to PS)
- Aortic dextroposition (shifted to right, sit over left and right ventricles)
tetralogy of fallot cause
Venous blood shunted from R to L through VSD & out aorta into systemic circulation → cyanosis
ruminant heart
Valvular hemocysts/lymphocysts
incidental finding
Dilated blood- or lymph-filled vascular spaces on AV valves
inflammation of blood vessels
VASCULITIS
inflammation of arteries
ARTERITIS
inflammation of many arteries
POLYARTERITIS
inflammation of veins
PHLEBITIS
inflammation of lymphatic vessels
LYMPHANGITIS
damage to endothelial & smooth muscle cells will cause
edema, hemorrhage, thrombosis
vasculitis can be caused by
infectious- viral, bacterial, fungal, parasitic
immune-mediated- Polyarteritis nodosa, Idiopathic necrotizing polyarteritis (“beagle pain syndrome”)
“hardening of the arteries”
ARTERIOSCLEROSIS
subset of arteriosclerosis accompanied by plaques of fatty material in the arteries
ATHEROSCLEROSIS
uncommon in animals
arterial mineralization is caused by
vitamin D toxicosis, Johne’s disease, others
atherosclerosis in animals is caused by
high cholesterol diet
dogs- hypothyroidism and DM
leads to narrowing of the arterial lumen→ ischemia and infarcts
gross findings of atherosclerosis
fibrofatty + mineralized plaques in vessel walls → thick rigid vessels with narrow lumens
Localized vascular dilation due to thinning or weakening of the vessel wall
aneurysm
what are some causes of aneurysm
Copper deficiency
Strongylus vulgaris migration- horse parasite to mesenteric artery
idiopathic
tumor of Blood vessel origin that is cancerous vs benign
HEMANGIOMA- benign
HEMANGIOSARCOMA
Aortic/carotid body tumor are called
CHEMODECTOMA
hemangioma- benign neoplasm of vascular endothelial cells
well differentiated- blood filled spaces
hemangiosarcoma- malignant neoplasm of vascular endothelial cells
right auricle of dogs- blood filled mass
what happens if hemangiosarcoma in dogs burst
usually on right auricle of heart
will bleed into pericardial sac- cause cardiac tamponade
common primary sites of hemangiosarcoma in dogs
Right atrium auricle
* Liver
* Spleen
* Skin/subcutis
* Fat around urinary bladder
lymphangisarcoma in cats are usually found —
ventral abdomen
oozy- bruisy appearance
Infiltrative endothelial neoplasm affecting ventral abdominal dermis/subcutis in cats
dog limb
canine perivascular wall tumor
hemangiopericytoma
Infiltrative mesenchymal neoplasm; may recur locally but seldom metastasize
aortic body tumor (chemodectoma)
Originates from aortic body (chemoreceptor that detects changes in blood O2, CO2, pH, etc.)
chemodectoma are found in — type of dogs
brachycephalic - boxer
aortic body tumor- found on heart base
may compress great vessels/ atria
cardiac lymphosarcoma
tan masses- can be seen everywhere
common sites of cardiac lymphosarcoma (LSA)
right atrium,
abomasum, uterus, spinal
canal, retrobulbar region,
kidney, lymph nodes
bovine leukemia virus is associated with what cancer
cardiac lymphosarcoma (LSA)
Restrictive cardiomyopathy exists is several forms. One common form is left ventricular endocardial fibrosis (LVEF) in cats. The endocardial fibrosis along the outflow tract of the left ventricle makes the ventricle more rigid, “restricting” its ability to dilate and fill with blood.
What is believed to be the preceding lesion of LVEF in cats?
endomyocarditis
What is the term for enlargement of the heart?
cardiomegaly
What cell adaptation is usually responsible for increased heart weight?
Myocardial hypertrophy
what can cause this
HCM and thyrotoxic cardiomegaly
heart
Dilated cardiomyopathy (DCM)
What gross abnormalities do you see, and what microscopic changes would you expect to find?
The margins of the mitral valve leaflets are thickened, nodular, and opaque with a glistening surface. These features are consistent with endocardiosis, an idiopathic age-related degenerative valvular lesion of dogs characterized by proliferation of loose fibroblastic tissue with a wispy blue-gray mucopolysaccharide matrix.
What gross abnormalities do you see, and what microscopic changes would you expect to find?
vegetative valvular endocarditis
There are crumbly (friable) red-tan masses attached to the mitral and aortic valve leaflets, consistent with vegetative valvular endocarditis. Microscopically, these masses are septic thrombi consisting of fibrin (F), bacteria (B), and neutrophils (N).
Of the two dog hearts, endocarditis or endocardiosis, which would be more likely to have secondary infarcts in other organs and why?
endocarditis
The dog in question #2 would be most likely to have infarcts in other organs because the valvular thrombi could fragment, sending thromboemboli into the systemic circulation. These septic thromboemboli can carry bacteria to other organs and potentially block blood flow to those organs, leading to infarcts.
If the lesion were on the right side (tricuspid or pulmonic valve) instead of the left, thromboemboli could enter the pulmonary circulation leading to embolic pneumonia and/or infarcts (though pulmonary infarcts are relatively uncommon).
heart
What abnormalities do you see on the atrial endocardium, and what are some possible underlying causes for these findings?
endocardial mineralization
There are multifocal raised wrinkled gritty white plaques on the endocardial surface, consistent with endocardial mineralization. A nodular red-tan thrombus adheres to the endocardium next to one of the mineralized plaques (right side of image). Endocardial injury due to necrosis/mineralization or subsequent inflammation likely predisposed to thrombosis at this site.
Endocardial mineralization in dogs can occur due to a variety of causes, including renal failure (uremia) and vitamin D toxicosis (e.g., due to oversupplementation of vitamin D or ingestion of cholecalciferol-based rodenticides). Causes in other species include ingestion of plants containing vitamin D analogs (more common in herbivores) and Johne’s disease in cattle.
If the right atrial mass, metastatic hemangiosarcoma, would have ruptured, what clinical impact might it have had on this dog?
hemopericardium and cardiac tamponade
Inflammation of a vein
PHLEBITIS
what kind of damage in heart
proliferative endarteritis
inflammation of the arterial wall
A classic example of PHLEBITIS is —, a mutated form of the feline enteric coronavirus
feline infectious peritonitis (FIP)
inflammation of the membrane lining the abdominal wall and covering the abdominal organs.
what form of FIP
feline infectious peritonitis (FIP)
Effusive (wet) form - characterized by thick stringy yellow cavitary effusions, like this fibrinous effusion in the peritoneal cavity (due to leakage of fluid and protein from injured veins)
what form of feline infectious peritonitis (FIP)
Non-effusive (dry) form - characterized by perivascular gray-white plaques of pyogranulomatous inflammation (a mixture of neutrophils, epithelioid macrophages, lymphocytes, and plasma cells), like these plaques centered on veins along the surface of a kidney:
heart worm will cause what type of right ventricular hypertrophy: concentric or eccentric, and how would this change appear grossly?
Pressure overload would lead to concentric hypertrophy of the right ventricle. The ventricular wall would be thickened due to addition of sarcomeres in parallel, and the ventricular chamber would be reduced in size.
What is the term for inflammation of the pleural cavity?
Pleuritis
