x exam 2 cardiovascular defects Flashcards
heart murmurs are
abnormal turbulence and blood flow through the heart
systolic murmus occur during
sytole between 1st and 2nd heart sounds
systolic murmurs associated with
closure of AV valves
diastolic murmurs occur during
diastole between 2nd heart sound of one cardiac cycle and 1st heart sound of next cardiac cycle
diastyolic murmurs are associated with
closure of aortic and pulmonic valve
acyanotic cardiac malformations include
pulmonary stenosis aortic stenosis ventricular septal defect atrial septal defect ectopia cordis
what is pulmonary stenosis
narrwoing of pulmonary outflow tract
pulmonary stensosis causes what kind of murmur
systolic murmur (poststenotic turbulence)
poststenotic dilation of pulmonary trunk occurs due to
high velocity blood flow
what are the long term consequences of pulmonary stenosis
dilation and hypertrophy of right ventricle and right heart failure
common dog breeds that get pulmonary stenosis
beagle english bulldog fox terier chihuahua samyed old english sheepdog miniature schnauzer
aortic stenosis is
narrowing of systemic outflow tract
what kind of murmur occurs with aortic stenosis
poststenotic turbulence (systolic murmur)
poststenotic dialtion of aorta due to
high velocity of blood flow (slower to appear compared to pulmonary stenosis)
what are the long term consequences of aortic stenosis
dilation and hypertrophy of left ventricle; left heart failure
aortic stenosis may be inherited in
boxers and newfoundlands
other common breeds to get aortic stenosis
german shephard germa short-haird pointers springer spaniel fox terier english bulldog siamese cat
ventricular septal defect is the
opening in interventricular septum
most commonly ventricular septal defect located ______. Why?
dorsally; failure to close membranous portion of interventricular septum (near septal cusp of R AV valve)
what kind of murmur occurs with ventricular septal defect
systolic
what are the long erm consequences of ventricular septal defect
small opening may not comporomise animal
larger openings typically create left heart problems
severe cases may also create right heart problems
ventricular septal defect is often an incidental finding in
bovine necropsy
ventricular septal defect occurs commonly in
siberian husky
atrial septal defect is the
failure to close a foramen
patent foramen ovale is the most common
septum primum does not fuse to septum secundum
if only failure is fusion, what are the clinical signs
no clincial signs when pressures of atria are normal
if septum primum does not completely cover foramen ovale
allows abnormal blood flow
atrial septal defect could also be a
persistent foramen primum or enlarged or persistent foramen scundum
what kind of murmur occurs with atrial septal defect
systolic murmur due to blood shunted from left atrium to right atrium
what are the long term consequences of atrial septal defect
dilation and hypertrophy of right atrium and ventricle
right heart failure
may progress to include left heart failure
what common breeds for atrial septal defet
boxers
samoyeds
what is ectopia cordis
delay in descent of heart during body folding; heart is found in neck instead of thorax
occasionally ____ does not form properaly and heart is found ventrally outside thoracic cavity
sternum
ectopia cordis most commonly seen in
cattle
what are the cyanotic cardiac malformations
tetralogy of fallot transposition of great vessels persistent truncus arteriosus abnormal vessels failure to close unique fetal circulatory structures patent ductus arteriosus
tetralogy of fallot consists for 3 primary and 1 secondary lesion including
pulmonic stenosis
ventricular septal defect
dextroarota (aorta shifted abnormally to right)
right ventricular hypertrophy (SEOCNDARY)
Why does cyanosis occur with tetralogy of fallot
deoxygenated blood from right ventricle enters aorta
what elicits marked cyanosis
limited exercise
what are the clinical signs of tetralogy of fallot
poor growth
fatigue
dyspena
syncope (poor oxygenation)
tetralogy of fallot is more common in
ruminants and dogs; may be inherited n keeshonds
transposition of great vessels is
failur of aorticopulmonary septum to develop as a spiral resulting in reversal of pulmonic and systemic outflow tracts
why does this cause cyanosis
2 separate, closed circulations (1 pulmonary loop and 1 systemic loop)
clinical signs of transposition of great vessesl
incompatible with life after birth unless a left-right shunt is present (many also have ventricular septal defect)
persistent truncus arteriosis is
failure of aorticuopulmonary septum to develop at all, truncus arteriosus does not develop into separate pulmonary trunk and aorta
why does persistent truncus arteriosis cause cyanosis
mixing of oxygenated and deoxygenated blood in single outflow tract leaving heart to lungs and body
persistent righ aortic arch is caused by
right 4th aortic arch becomes the aortic arch instead of the left
if right 6th aortic arch also
ductus arteriosus instead of left= normal physiologic function
if left 6th aortic arch
ductus arteriosus and left segment of dorsal aorta persist=vascular ring around esophagus and trachea (stricutre point affecting function)
aberrant right subclavian artery
right 4th arch degenerates, leaving right subclavian artery to arise soley from right 7th drorsal intersegmental artery and dorsal aorta (caudal to aortic arch); depending on path, can create a partial vascular ring that constricts the esophagus
patent foramen ovale
interatiral septal defect
patent ductus venosus
connection between hepatic protal vein and caudal vena cava remains open= portosystemic shunt (other types exist)
venous blood from GITt continues to bypass liver
what are the deficits of patent ductus venosus
acumulation of toxic substances (ammonia causes neuroligc dysfunction including abnormalbehaviors and seizures)
occur in what breeds
dogs (irish setter, irish wolfhounds) and cats
patent ductus arteriosis
increase pressure in aorta and left ventricle forces blood into pulmonary artery
what murmur occurs with patent ductus arteriosus
continuous murmu associated with aortic and pulmonic valve PMIs
what clinical signs occur
initial right heart hpertrophy (failure, eventually left also affected)
