Cardiovascular diseases

Question 1

Most common congenital heart defects

Answer 1

Ventricular septal defect (VSD); (most common cardiac defect in calves)

Tetralogy of Fallot (almost always lethal; VSD + pulmonary stenosis + dextral position of the aorta that overrides both ventricles, plus secondary right ventricular hypertrophy);

Atrial septal defect (ASD);

Transposition of great vessels;

Patent ductus arteriosus (PDA) (rare as a single defect);

Question 2

Treatment of congenital cardiac defects

Answer 2

Euthanasia or early slaughter

Question 3

Specific cardiac signs of white muscle disease

Answer 3

variable, subtle or dramatic; arrhythmias; persistent tachycardia (>120 bpm); murmurs may be present; exercise intolerance; cyanosis; dyspnoea (caused by cardiac lesions); congestive heart failure signs; acute death (e.g., spontaneously, after exercise or restraint);

Question 4

Bovine Leukocyte Adhesion Deficiency (BLAD)

Answer 4

inherited autosomal-recessive trait in Holstein-Friesian cattle

severe deficiency of neutrophil Mac-1 (CD11a, b, c/CD18)

results in neutrophils with deficient β2 integrin expression, prevents adherence to vascular endothelium and the capacity of subsequent migration into the tissue sites of inflammation

Onset early in life, poor growth, chronic or PI

diarrhoea, pneumonia, ringworm lesions, persistent keratoconjunctivitis, gingival ulcer, loose teeth, tooth abscesses, poorly healing dehorning wounds

Only palliative treatment

Question 5

Bovine hereditary dilated cardiomyopathy

Answer 5

Type 1 - Cardiomyopathy in Hereford cattle
- rapid growth
- short curly coat
- sudden death
- dyspnoea, bloody froth from nose
- patchiness of myocardium

Type 2 - Cardiomyopathy in Japanese Black cattle
- death preceded by agonizing dyspnoea
- pulmonary oedema
- oedema, ascites, hydrothorax etc.

Type 3 - Dilated cardiomyopathy in Holstein-Friesian
- sudden onset congestive right sided heart failure
- oedema and engorgement of various areas
- signs of congestive heart failure

Question 6

Septic pericarditis

Answer 6

most commonly puncture of the pericardium by a metallic foreign body that originates in the reticulum

detectable pericardial effusion and heart failure signs

Positive pain response to percussion of ventral chest or xiphoid

Traumatic reticulopericarditis:
§ Purulent and foetid fluid
§ Commonly visible presence of fibrin clots that can obstruct needle;
§ Elevated protein and WBC with neutrophils as major component;
§ Bacteria easily detected in gram-stained smears;
Normal pericardial fluid: protein <25g/L; WBC £5000/mL with mononuclear cells as a major component;

Poor prognosis, attempt surgery for expensive cattle

Question 7

Idiopathic haemorrhagic pericarditis

Answer 7

Clinical signs:
o Jugular distention; severe submandibular and brisket oedema + acute reduction of appetite and milk production over 24 to 72 hours; mammary vein can be distended and turgid for the stage of lactation;
o Typically, cattle are afebrile or low-grade fever; normal to mildly elevated heart rate and respiratory rate;
o Heart auscultation: muffling heart sounds or a washing-machine type murmur

Treatment:
Corticosteroid administration (0.1mg/kg BW, over 3 days), alone or combined with pericardial drainage. The combination seems to give the best long-term survival.
Antibiotherapy (e.g., penicillin) is recommended in case of pericardial drainage

Question 8

Bacterial endocarditis

Answer 8

Most commonly Trueperella

Most commonly affects tricuspid valve

persistent or recurrent fever; tachycardia; systolic heart murmur

can cause permanent distortion of valves

Treatment requires long-term antibiotic administration to cure bacterial endocarditis

Furosemide can be necessary in case of venous distention