Smith.Ch6.AlterationsinCardiovascularandHemolymphaticsystems Flashcards
Define Edema
abnormal accumulation of extracellular fluid in the interstitial spaces of the tissues or in body cavities that can be generalized or localized
What are the forces that govern fluid movements at the capillary level?
- intravascular hydrostatic pressure
- interstitial fluid hydrostatic pressure (keep fluid in capillary)
- Intravascular colloid oncotic pressure exerted by plasma proteins
- interstitial fluid colloid osmotic pressure
- vascular surface area capable of fluid transport
- vascular permeability to proteins and water
What are the most common causes of increased capillary permeability?
trauma
infection
endotoxemia
hypersensitivity (allergic) vasculitis
In horses and ruminants, what is the most common causes of increased hydrostatic pressure?
-CHF
-venous thrombosis
-liver dz causing obstruction of portal venous thrombosis
-lymphadneopathy
-cranial mediastinal mass
-compression bandage
-limb immbolization
topica administraiton of counterirritants
CHF cause of increased hydrostatic pressure?
pulmonary & vascular systemic congestion
–compensatory salt and water retention increases ventricular diastolic, venous and capillary pressure= formation of generalized edema
Causes of hypoproteinemia?
- decreased production of plasma proteins: starvation, liver dz, severe heart failure
- augmented loss of plasma proteins resulting form kidney disease, PLE, (johnes disease, chronic inflammatory bowel disease), peritonitis, or pleuritis
lymphedema occurs when lymphatics are absent or obstructed, what are causes of this edema in horses/cattle?
-congenital absence– rare
-tumor
-local inflammation (lymphangitis or lymphadenitis)
-elevated ventral venous pressure (ie: heart failure)
Common causes of peripheral edema, pleural effusion, and ascites in horses
-chronic right sided or biventricular heart failure
-pericarditis
-pleuritis/pleuropneumonia
-peritonitis
-pregnancy
-neoplasia: lymphosarcoma
-cranial mediastinal mass
-hypoproteinemia
-liver dz
-GI malabsorption: infalmmatoyr bowel dz, neoplasia, parasitism
-vasculitis
-equine infectious anemia
-purpura hemorrhagica
-Anaplasma phagocytophilum
-equine viral arteritis
-thrombophlebitis
-lymphatic obstruction
-ulcerative lymphantiis
-lymphadenitis (corynebacterium pseudotuberculosis abscesses)
Trauma
-Equine viral arteritis
-Thrombophlebitis
Uncommon causes of peripheral edema, pleural effusion and ascites in horses
-aortic cardiac fistula
-aortopulmonary fistula
heart base tumor other than lymphosarcoma
-neoplasia: mesothelioma, melanoma, plasma cell myeloma, squamous cell carcinoma, fibrosarcoma
-starvation
-kidney dz, glomerulonephritis, amyloidosis
-ionophore toxicity
-copper deficiency
-counterirritant application
-hemodilution
-ruptured bladder
-Cassia occidentalis toxicity
Common causes of peripheral edema, pleural effusion and ascites in ruminants
-chronic right sided heart failure
-high altitude disease (brisket disease)
-cor pulmonale
-pericarditis (traumatic reticulopericarditis)
-pleuritis
-pregnancy (udder edema in heifers)
-cr mediastinal mass: lymphosarcoma
-hypoproteinemia
-liver disease
-kidney disease: amyloidosis, glomerulonephritis
-Gi malabsorption, lymphosaromca, Johnne’s dz, parasitism
-lymphatic obstruction (corynebacterium pseudotuberculosis, lymphosarcoma)
-thrombophlebitis
-urolithiasis ruptured urethra or bladder
Uncommon causes of peripheral edema, pleural effusion, and ascites in ruminants
-mycoplasma wenyoni
-idiopathic hemorrhagic pericardial effusion
-chronic right sides heart failure d/t cardiomyopathy, infectious myocarditis, ionophore toxicity
-starvation
-hemodilution
-copper deficiency
-vasculitis
trauma
-caudal vena caval thrombosis
-anaplasmosis
-gossypol toxicity
-cassia occidentalis
-phalaris spp toxicity
-oxytropis (locoweed) toxicity
Common causes of cardiac arrythmias in horses
-excitement
-autonomic imbalance
-fever
-sepsis
-toxemia
-hypoxemia
-colic
-disorders of acid base or electrolyte homeostasis
-congenital defects
-myocarditis
-valvular disease
-idiopathic (presumptive myocardial fibrosis or fibrofatty infiltrate)
Uncommon causes of cardiac arrhythmias in horses
-ionophore toxicity
-ziplatrerol toxicty
-anesthesia
-other drugs
-pericarditis
-cardiomyopathy
-cardiac or heart base tumor
-aortic root rupture
-aortopulmonary rupture
-atypical myopathy
-aortic regurgitation
-severe hemorrhage
-dynamic upper airway obstruction
-rattlesnake envenomation
-cardiotoxic plants
-hyperthyroidism (iatrogenic)
Common causes of cardiac arrythmias in ruminants
-GI disease
-Lymphosarcoma
-valvular heart disease
-myocardial diseases
-brisket dz
-pericarditis
-cor pulmonale
-excitement
-foot rot
-fever
-sepsis
-toxemia
-disorders of acid-base or electrolyte homeostasis
-myocarditis
Uncommon causes of cardiac arrythmias in ruminants
-ionophore toxicity
-Beta-adrenergic agonist (zilpaterol) toxicity
- anesthesia
-hypoxemia
-cardiomyopathy
-autonomic imbalance
-cardiotoxic plants (Rhododendron and Taxus spp.)
Automaticity/ the ability to initiate action potentials spontaneously is a property of cells located where?
-sinus note
-part of atria
-AV junction
-His-purkinje system
Primary arrhythmias can be caused by pathologic conditions of the heart, such as:
myocarditis
valvular disease
conduction system abnormalities
pericarditis
Secondary arrhythmias develop in the absence of heart disease, such as those caused by:
-excitement
-fever
-sepsis
-hypoxemia
-acid-base disorders
-electrolyte abnormalities
-Gi disturbances
-anemia
-severe hemorrhage
-anesthesia
-ionophores
-other drugs
-toxemia
Placement of base-apex lead for ecg
negative lead– 2/3 rigth jugular furrow from the ramus of the mandible to the thoracic inlet
lead 1 or II: right arm
lead III: left arm
Common causes of cardiac murmurs in horses:
valvular regurgitation
congenital defects
anemia
excitement
fever
functional murmur
exercise
Uncommon causes of cardiac murmurs in horses
aortic cardiac fistula
aortopulmonary fistula
cardiomyopathy
pericarditis
cranial mediastinal abscess
Common causes of cardiac murmurs in ruminants
-anemia
-excitement
-fever
-functional murmur
-valvular regurgitation
-congenital defects
-lymphosarcoma
-pericarditis (usually traumatic reticulopericarditis)
Uncommon causes of cardiac murmurs in ruminants
-cardiomyopathy
-myocarditis
What is the graded scale of cardiac murmurs?
Grade 1: soft
Grade 2: soft murmur heard immediately
Grade 3: murmur of moderate intensity
Grade 4: loud murmur, with faint palpable thrill
Grade 5: loud murmur with palpable thrill
Grade 6: loud murmur, audible with stethoscope held away form the chest
The presence of a musical murmur indicates:
vibration of a cardiac structure such as rupture of one of the chordae tendinea or torn valve leaflet
Diastolic murmurs occur between which heart sounds?
S2 and S3
(ventricular filling murmurs)
OR
S2 and S1
(aortic regurge or rarely, pulmonic)
Which lesion is described as a continuous washing machine murmur?
**heard in a foal
patent ductus arteriosus
Which lesion is described as a continuous washing machine murmur?
**heard in an adult
aortic cardiac fistula secondary to rupture of the aortic root or of a sinus Valsalva aneurysm
aorticopulmonary fistula–Fresian horses
A continuous washing machine murmur in cattle is heard over the left cardiac areas is associated with what lesion?
traumatic pericarditis
–d/t accumulation of fluid, gas, fibrin within the pericardium
Reasons for muffled heart sounds:
- pericardial effusion: displacement of the heart from the thoracic wall by fluid
- abscess or tumor: soft tissue mass
- pneumothorax, pneumomediastinum, or emphysema: air
Common causes of muffled heart sounds in horses
obesity
large or thick chest wall
pericarditis or pericardial effusion
neoplasia lymphosarcoma
pleural abscess
chronic heart failure
Uncommon causes of muffle heart sounds in horses
pulmonary emphysema
pneumothorax
neoplasia: mesothelioma, squamous cell carcinoma, fibrosarcoma
Common causes of muffled heart sounds in ruminants
pneumothorax
idiopathic hemorrhagic pericardial effusion
Common causes of exercise intolerance, weakness and syncope in horses
myocardial disease
cardiac arrhythmias
aortic or pulmonary artery rupture
aortoiliac femoral thrombosis
congenital heart defects
chronic heart failure
pericardial disease
hyperkalemic periodic paralysis
Common causes of exercise intolerance, weakness or syncope in ruminants:
myocardial disease
cardiac arrhythmias
congenital heart defects
chronic heart failure
define syncope
sudden collapse and loss of consciousness (fainting)
The clinical signs of exercise tolerance, weakness or collapse that is caused by cardiovascular disease results from
failure to maintain cardiac output
– inability to regulate heart rate or stroke volume
At what heart rates and mechanism do horses maintain cardiac output?
INC cardiac output
HR <210 beats/min: tachycardia
HR 210-240: INC stroke volume
heart rates greater than 240 bpm limit cardiac output by
decreasing the time for diastolic perfusion of the myocardium or by limit in stroke volume because of the short diastolic intervals leave inadequate time for ventricular filling
What are the most common bradyarrythmias to cause clinical signs?
complete heart block
advanced second degree heart block
Common causes of jugular venous distention and pulsation in horses
right sided heart failure
left-sided heart failure with pulmonary hypertension
cardiomyopathy
atrial fibrillation
tricuspid regurgitation
cranial mediastinal mass
lymphosarcoma
abscess
jugular venous phlebitis and thrombosis
Uncommon causes of jugular venous distention and pulsation in horses
ionophore toxicity
pericarditis
myocarditis
ventricular tachycardia
squamous cell carcinoma
fibrosarcoma
cor pulmonale
chronic obstructive pulmonary disease
overhydration
Common causes of jugular venous distention and pulsation in Ruminants
right sided heart failure
left sided heart failure with pulmonary hypertension
Vitamin E and selenium defiiciency (white muscle disease)
cardiomyopathy
tricuspid regurgitation
pericarditis
jugular venous phlebitis and thrombosis
heart base abscess
heart base tumor lymphosarcoma
cor pulmonale caused by chronic pneumonia
brisket disease
Uncommon causes of jugular venous distention and pulsation in ruminants
ionophore toxicity
idiopathic hemorrhagic pericardial effusion
overhydration
cranial mediastinal mass
Abnormal jugular pulsation are associated with what side of the heart disease?
right sided
–R-CHF
–constrictive pericarditis
-cardiomyopathy
-tricuspid regurgitation
Common causes of painful peripheral swellings in horses
thrombophlebitis
abscess (Corynebacterium pseudotuberculosis)
cellulitis
hypersensitivity vasculitis (complicated by skin necrosis and secondary infection)
Equine viral arteritis
Equine granulocytic ehrlichiosis (Anaplasma phagocytophilum)
equine infectious anemia
purpura hemorrhagic
clostridium spp myositis
septic tenosynovitis
bursitis
mm disruption/hematoma
fracture
insect bite
application of topical counter irritants, firing or soring
Uncommon causes of painful peripheral swellings in horses
frostbite
piroplasmosis
ulcerative lymphangitis
epizootic lymphangitis
glanders
melioidosis
sporotrichosis
immune vasculitis
aortoiliac thrombosis
sporadic lymphangitis
congenital lymph node and lymphati cdysgenesis
hemangiosarcoma
snakebite
Common causes of painful peripheral swellings in Ruminants
thrombophelbitis
abscess
clostridial myositis
malignant edema
blackleg
mm disurption/trauma/hematoma
carpal hygroma
fescue foot
ergotism
cellulitis (inj site or wound)
fracture
insect bite
frostbite
Uncommon causes of painful peripheral swellings in ruminants
disseminated hemangiosarcoma
heartwater disease (Ehrlichia rumination, exotic)
snake bite
septic tenosynovitis
bursitis
Common causes of enlarged lymph nodes in horses
strangles
lymphosarcoma
upper respiratory infection
Corynebacterium pseudotuberculosis lymphadenitis
Uncommon causes of enlarged lymph nodes in horses
ulcerative lymphangitis
epizootic lymphangitis
sporadic lymphangitis
glanders
melioidosis
granulomatous lymphadenitis
plasma cell myeloma
tuberculosis
hemolytic uremic syndrome
Common causes of enlarged lymph nodes in ruminants
caseous lymphadenitis (Corynebacterium pseudotuberculosis)
lymphosarcoma (including bovine leukosis virus)
abscess or cellulitis of area drained
Uncommon causes of enlarged lymph nodes in ruminants
tuberculosis
sporadic bovine encephalomyelitis
malignant catarrhal fever
Describe when the arterial pressure occurs with heart contraction
-opening of the aortic valve & ventricular ejection
-rises rapidly in early systole
-pulse pressure reach peak and declines as ventiruclar ejection slows
Common causes of abnormal peripheral pulses in horses
dehydration
shock
toxemia
congestive heart failure
electrolyte imbalances
acid-base disorders
hypertension
hypotension
exercise
fever
laminitis
aortic regurgitation
cardiac arrhythmias
Uncommon causes of abnormal peripheral pulse in horses
aortic cardiac fistula
aortopulmonary fistula
peripheral arteriovenous shunt
patent ductus arteriosus
When do hyperkinetic arterial pulses occur in patients with:
-INC cardiac output (fever, exercise, excitement)
-INC stroke volume
-bradycardia
-aortic valave regurgitation
-patent ductus arteriosis
-aortic cardiac fistulas
-aortopulmonary fistulas
In aortic valve regurgitation, the hyperdynamic pulses is caused by:
increased stroke volume (regurgitated blood int he left ventricle)
-followed by rapid runoff of pressure later in systole (as a result of regurgitation)
Hypokinetic pulses are present in patients with diminished stroke volume, as seen in what conditions?
hypovolemia
left ventricular failure
mitral or aortic valve stenosis (RARE in lg animals)
Common causes of abnormal puerperal pulse in ruminants
dehydration
shock
toxemia
congestive heart failure
electrolyte imbalances
acid-base disorders
fever
cardiac arrythmias
Uncommon causes of abnormal peripheral pulse in ruminants
patent ductus arteriosus
aortic regurgitation
peripheral arteriovenous shunt
