Ch 30 Cardio Flashcards
Can a QRS complex character in large animals reflect chamber enlargement?
NO. not sensitive or specific for ventricular enlargement
Why is peak blood flow in large animals with valvular heart disease difficult to estimate?
Because optimal doppler signals are obtained with the ultrasound beam parallel to the blood flow being evaluated. Thus the peak velocity is underestimated
What is the sedative of choice for large animals undergoing an ECG?
Acepromazine, given ahead of time
What is the most commonly reported congenital cardiac defect in large animals?
Ventricular septal defect. This can be evaluated appropriately with doppler
Cardiac and great vessel catheterization can determine what data?
-Pressure and waveforms
-Oxygen tension, saturation, content
-cardiac output
What does PAWP assess?
Pulmonary artery wedge pressure assesses left atrial mean pressure, left ventricular function, and fluid therapy
Describe a VSD’s character in 1-2 sentences
Loud, grade 4-6 plateau pansystolic murmur with PMI in tricuspid area. Murmur on the L has a PMI at the pulmonic valve area.
What are the characteristics of an innocent flow murmur of neonates?
-Crescendo-decrescendo shape
-PMI L heart base
-lack of radiation
-low-moderate intensity
What valvular insufficiency do horses with VSD often develop later in life?
Mitral regurgitation
What clinpath abnormality would indicate a complicated VSD?
polycytemia
Pressure increases in which chambers in animals with VSD indicate cardiac failure?
Increased pressure in the left or right ventricles during diastole
Horses with what size of VSD can still race successfully?
VSD must be </= 2.5 cm
What VSD to aortic root ratio in nonracing horses and ponies is likely hemodynamically benign?
ratio < 0.3
What metrics of a VSD would indicate reduced life expectancy and tendency to develop CHF?
Defect > 3.5 cm, VSD/AR ratio 0.64, peak shunt velocity < 3.5 m/s
What are classic signs of a PDA on cardiac auscultation?
-continuous machinery murmur
-loudest at L ICS 3-4 at point of shoulder level (can be heard on L or R)
-Bounding arterial pulses due to runoff of blood from systemic to pulmonary circulation
-Murmur intensity increases with exercise, excitement, inc HR
In foals, a PDA normally closes by what time after birth?
96 hours
What physiologic “pressures” usually make a PDA close shortly after birth?
-lowered pulmonary vascular resistance
-increased systemic resistance
-increased blood volume
-increased left ventricular pressure
A right to left shunt occurs due to what pressure balances/imbalances?
When pulmonary resistance equals or exceeds systemic vascular resistance
What are the components of Tetralogy of Fallot? What does Pentalogy include?
- Overriding aorta
- VSD
- Obstructed pulmonary arterial flow
- 2* R ventricular hypertrophy
- ASD or PDA
Cyanosis is noticed when ______ g/dL of hemoglobin are reduced/unoxygenated
> 5
What common ER treatment for respiratory distress is unhelpful in patients with R to L shunts?
Oxygen administration
What clinpath abnormalities may be seen in animals with Tet or Pent of Fallot?
Increased PCV, RBC, and polycytemia
A client has a yearling with tetralogy of fallot. she wants to know, is this condition heritable?
No. Or at least no evidence yet to say that
How does an atrial septal defect usually sound on auscultation?
holosystolic, crescendo-decrescendo at the left heart base (because more volume is being ejected across the pulmonic valve)
