7. Congenital cardiac diseases in dogs and cats. Diseases of the pericardium in dogs and cats. Flashcards
List the congenital diseases?
Aortic stenosis?
aortic stenosis diagnosis and treatment?
Treatment
May not be necessary in mild cases
Medical management: Beta-blocker e.g Atenolol → ↓ Myocardial
oxygen demand; Prolongs diastole; ↓ Wall stress
Surgery: Balloon dilation; Cardiopulmonary bypass
PDA?
Pulmonic stenosis?
Ventricular septal defect?
Ventricular Septal Defect (VSD)
Usually located just under the septal tricuspid leaflet; Causes volume
overload → Eccentric hypertrophy
Small defects: Usually diagnosed by doppler and don’t usually hold
clinical significance
A
Large defects: Easily diagnosed; May lead to left-sided CHF; Very
large defects may cause the ventricles to act as a common chamber.
Clinical signs: Asymptomatic; Exercise intolerance; CSx of LS-CHF
Auscultation: Holosystolic murmur
Diagnosis:
Echocardiography: Left heart dilation
Radiology: Left side enlargement; Sometimes RV enlargement
ECG: Normal; Indicative of LA/LV enlargement
Treatment: Cardiopulmonary bypass
Tricuspid dysplasia, mitral dysplasia and other congenital cardiac disease?
Tricuspid Dysplasia
Causes volume overload → Eccentric hypertrophy
Predisposed breeds: German Shepherd; Labrador retriever; Bobtail;
Dog de Bordeaux
Young dogs > Older dogs
Males > Females
Treatment: Valvuloplasty
Mitral Dysplasia
Causes volume overload → Eccentric hypertrophy
Predisposed breeds: German Shepherd; Newfoundland; Golden
retriever; Bull terrier; Great Dane; Mastiff; Dalmatian
Young dogs > Older dogs
Treatment: Valvuloplasty
Other Congenital Cardiac Diseases
§ Tetralogy of Fallot
- Pulmonic stenosis
- Ventricular septal defect
- Dextroposition & Aortic overriding
- Right ventricular hypertrophy (which comes
later)
§ Persistent right aortic arch
§ Atrial septal defect
§ PPDH (Peritoneopericardial diaphragmatic hernia)
Congenital pericardial diseases?
Diseases of the pericardium lead to CSx associated with congestive heart failure
Congenital Pericardial Diseases
May be clinically silent; May be associated with other congenital defects
Pericardial cysts: Compression of heart & lungs
Partial defects: Herniation of part of the heart through the
pericardium
PPDH (Peritoneal-Pericardial Diaphragmatic Hernia)
CSx associated with cardiac/pulmonary compression or compression
of the abdominal viscera which are entrapped.
Treatment: Surgery
Good prognosis
Pericardial effusion (Acquired)?
Pericardial effusion (Acquired)
Build-up of excess fluid within the pericardial cavity
Disposition
Large dogs > Small dogs; Males > Females; > 5yo
Cause
Usually idiopathic; Pericardial disease → Pericardial effusion
Cats
Heart failure
FIP
Cardiomyopathy; Lymphoma; Uraemia
Dogs
Idiopathic pericarditis
Cardiac neoplasia: Hemangiosarcoma; Heart base tumours
Mesothelioma
PATHOGENESIS
Chronic causes of effusion are more common
Transudative effusion: CHF; PPDH; Hypoalbuminaemia; Infection
causing ↑ vascular permeability
Exudative effusion: Infection; Non-infectious pericarditis (uraemia)
Haemorrhage: Neoplasia; Idiopathic; Trauma; Haemostatic
disorder; Pericardial mass
Clinical signs and pathology?
Diagnosis of pericardial effusion?
Treatment and prognosis of pericardial effusion?
TREATMENT
US-guided pericardiocentesis
§ Costochondral junction at ICS 4-5
§ Lab analysis of pericardial fluid: Cell count; SG; PCV; TP;
pH; Culture; Cytology
Medical management
§ Diuretics are contraindicated → ↓ Cardiac output
§ Purulent pericarditis → Abx
§ Anti-inflammatories
§ Treatment of any associated CHF
Other
§ Heart base tumours: Pericardiectomy
§ Idiopathic effusion: Subtotal pericardiectomy in cases of
recurrence
PROGNOSIS
§ Good: If non-recurring or if idiopathic
§ Poor: Neoplastic cases
Constrictive pericardial disease?
Constrictive Pericardial Disease (Acquired)
Dogs > Cats
Can be the result of pericardial effusion
PATHOGENESIS
Thickening/scarring of the pericardial layers + fluid → ↓ Ventricular
diastolic compliance → ↓ Ventricular filling at any given preload
CLINICAL SIGNS
§ CSx associated with RS-CHF
§ Abdominal distension
§ Tachypnoea
§ Laboured breathing
§ Syncope; Weakness
§ Weight loss
DIAGNOSIS
History: CSx; Same as with pericardial effusion
Echocardiography: Limited use
§ Pericardial fluid
§ Thickened, echogenic pericardium
§ ↓ Diastolic chamber size
Hepatojugular reflex test
Cardiac catheterisation
TREATMENT
Subtotal pericardiectomy
PROGNOSIS
Good if the epicardium & pericardium are not fused; Otherwise bad
