Cardio Flashcards
the three types of injectable selenium supplement in order of greatest selenium content
Mu-Se (5 mg/mL) -
labeled for weanling calves and mid-gestation beef cows
E-Se (2.5 mg/mL) - labeled for horses
Bo-Se (1 mg/mL) - labeled for calves, lambs, ewes, sows, piglets
differentials/mechanisms for ascites
heart failure (septal defect, valve failure, endocarditis, pericarditis, traumatic reticulo-pericarditis) with backup into Caudal vena cava -> leakage into abdomen. Liver dysfunction -> low oncotic pressure. May not be true ascites - hydrops,
differentials for muffled heart sounds
Pneumonia, plueropneumonia. pericardial effusion. pleural effusion. diaphragmatic hernia. abscess, mass, or air in mediastinum. pneumothorax. emphysema. fat.
typical signs/manifestations of CV disease
Edema, pleural effusion, ascites. Arrhythmias. Murmurs. Muffled heart sounds. exercise intolerance, weakness. syncope (fainting) Venous distension +/- pulsation. Painful peripheral swelling. Lymphadenomegaly.
Mechanisms of edema, and which are the most common in ruminants?
increased vascular permeability.
increased hydrostatic pressure in the vasculature
decreased oncotic pressure in vasculature
edema of lymph drainage.
increased oncotic pressure (doesn’t cause problems often)
signs that edema may be due to increased vascular permeability
Evidence of systemic inflammation/infection -
PE: pale MM, injected MM/sclera, petechiation, fever, tachycardia, tachypnea or dyspnea,
signs that edema may be due to increased hydrostatic pressure
venous distension/pulsation, tachycardia (if decreased cardiac output), murmur, arrhythmia, ascites, distal limb edema, …
DfDx: CHF, Tricuspid (RAV) valve insufficiency, Venous thrombosis, liver dz, portal v. obstruction…
edema due to decreased oncotic pressure occurs when:
Total Protein is below ___ and albumin is below ___
TP <5g/dL
albumin < 1.5 g/dL
three ways to get hypoproteinemia/hypoalbuminemia?
Don’t make it: starvation/inadequate protein in diet, liver dz
Lose it:
protein losing enteropathy, PL nephropathy, 3rd space loss (e.g. burns, uncommonly seen)
YOU screwed up (iatrogenic):
hemodilution
differentials for causes of lymphedema
tumor obstructing a lymph vessel or node.
trauma - damage to lymph vessels?
increased central venous pressure.
benign arrhythmias (sinus arrhythmia, sinus bradycardia) are typically due to ___
decreased feed intake/anorexia –> hypocalcemia!
pathologic arrhythmias most commonly seen in ruminants?
Atrial fibrillation, premature depolarization
pathologic arrhythmias are typically secondary to ___
GIT disease –> electrolyte disturbance, acid-base imbalance
the best way to treat pathologic arrhythmias in ruminants?
correct the electorlyte/acid base abnormality, usually the arrhythmia will resolve.
AV blocks occur when there is a delay between ___ & ___.
p wave & QRS complex
what are the types of AV block?
1st degree: increased time between P wave and QRS (prolonged P-R interval)
2nd degree: prolonged P-R interval with occasional dropped beats (2 normal for every 1 dropped?)
3rd degree: prolonged P-R interval with fewer than 2 beats for every dropped beat.
atrial standstill ECG findings?
NO P waves!
atrial standstill most commonly seen in what signalment and disorder?
calves with metabolic acidosis.
describe what happens to potassium during metabolic acidosis
the H+ gradient between intracellular and extracellular compartments gets messed up, causes K+ to move out of the cells –> hyperkalemia
describe the pathophysiology of atrial standstill
hyperkalemia -> myocardium membrane depolarization -> Opens Na+ channels, they become inactivated -> hyperkalemia causes repeated depolarization, but the Na+ channels have not been able to reset themselves (membrane repolarizaiton not taking place) -> cells are refractory to the depolarization signal -> atrial standstill –> can quickly progress to V-fib , asystole, and death
treatment for hyperkalemia/atrial standstill?
you need to do something FAST - Ca2+ IV is the best way to quickly treat these animals –> causes the membrane depolarization threshold to shift so that the electical conductivity of the heart can go back to normal. THEN you need to fix the hyperkalemia - bicarbonate will re-establish the acid balance, drive K+ back into cells. Insulin will also work.
causes of arrhythmias in ruminants
electrolyte abnormalities. pericarditis. valvular disease. myocardial disease. toxemia. Cor Pulmonale. Lymphosarcoma. Fever.
Reynolds’ number is calculated by the ratio of ___ to ___
velocity: viscosity
turbulence of blood flow occurs when Reynolds’ number is greater than
2000
animals are predisposed to murmurs if there is an (increase or decrease?) in velocity or (increase or decrease?) in viscosity of blood?
increased velocity
decreased viscosity
typically, murmurs can be heard after PCV falls below ___
25% (but not all animals with PCV<25 have a murmur)
PMI for murmurs: Pulmonic valve Aortic valve Mitral (LAV) valve Tricuspid (RAV) valve
PV: left, basilar, 3-4th ICS
AoV: left, basilar, 4-5th ICS, radiates up aorta
MV: left, apical, 5-6th ICS (near elbow)
TV: right, apical, 3-4th ICS (between shoulder & elbow)
systolic ejection murmur occurs between which heart sounds? describe the sound.
S1 & S2
increases in volume and then decreases <>
Holosystolic regurgitation murmur occurs between which heart sounds? describe the sound
S1 & S2
flat sound, same volume throughout systole.
diastolic decrescendo murmur occurs during which heart sounds? describe the sound
S4 & S1, S2 & S3
starts loud and then volume decreases
causes of ejection murmurs
innocent murmur (no clinical signs or lesion associated)
anemia, fever
Aortic or Pulmonic valve stenosis
Atrial or Ventricular Septal Defect, Tetrology of Fallot
