Heart develops outside the body cavity, due to incomplete body compartments
Acardiac monster attached to the placenta. Spherical, covered in hair
Patent ductus arteriosus
Foetal remnant which connects the aorta and pulmonary artery.
Blood shunts from aorta to pulmonary artery therefore leading to pulmonary hypertension.
Usually degenerates to the Ligamentum arteriosum
Sequelae to PDA
Right ventricular hypertension due to pulmonary hypertension
Patent foramen ovale
Hole which allows blood from the right atrium to by-pass the lungs during gestation
True septal defect
A hole (fault) in the septum between heart chambers.
Can be interatrial or interventricular.
With ventricular shunts are from left to right and lead to equal pressures in the chambers:
- Volume overload and eccentric hypertrophy in the right atrium
- Pressure overload and concentric hypertrophy in the left atrium
Valvular lesions which are associated with muscle/fibrous tissue deposition:
- Subvalvular - beneath the valve
- Valvular - valve itself
Leads to pressure overload and concentric hypertrophy of the right ventricle. Also jet lesions in the pulmonary artery.
Below the aortic valve a zone of circumferencial fibrosis.
Made up of proliferating mesenchyme, mucin and metaplastic cartilage.
Leads to pressure overload and concentric hypertrophy of the left ventricle. Also myocardial necrosis and fibrosis may be observed.
Tetralogy of fallot
- Ventricular septal defect
- Pulmonic stenosis
- Dextroposition of the aorta - aorta straddles right and left ventricles
- Secondary hypertrophy of the rght ventricle
Baby blue syndrome - cyanosis
Haemocyst/ lymphocyst - generally regress
Persistent right aortic arch
Ligamentum arteriosum forms a ring around the oesophagus and trachea.
Leads to cranial megaoesophagus - regurgitation
Peritoneopericaridial diaphragmatic hernia
Displacement of the intestine into the pericardium.
Transudate or exudate (+ fibrin - associated with mulberry heart disease)
Associated with generalised oedema and therefore cardiac tamponade and compression
Haemorrhagic pericardial effusion
Small deposits of blood
Large amounts of blood within the pericardium.
Atrial rupture due to haemangiosarc
Aortic rupture in horses
Due to pulmonary rupture/ oesophageal rupture
Exudate formed due to rupture of the thoracic duct
Describe this value.
Epicardial fat has become yellow and gelatinous. Due to fat metabolism (starvation).
Histologically appears oedematous and atrophic
Describe this lesion
What are the potential outcomes of the condition
Subacute diffuse severe fibrinous pericarditis
(traumatic, haematogenous, local spread of infection)
Histo - fibrin layer with n# over pericardium
Outcomes - death through septicaemia or chronicity (proliferating fibrosis) with compensatory hypertrophy &heart failure
Cause of fibrinous pericarditis in:
- Pasturella, C. chauvoei, Chlamidophila, collisepticaemia
- Haemophilus parasuis, streps, pasturella, Salmonella, Mycoplasma hyopneumoniae
- Chlamydia psittaci
Inflammation of several serous membranes - eg pleural, pericardium, peritoneum
Glasser's disease - Haemophilus parasuis
Accumulation of uric acids - found in reptiles/ birds
- Enzyme deficiency
- Increased catabolism - disease/ tumours
- Renal disease
Grossly see white urate crystals on the pericardial surface
Excess vitamin D intake or calcinogenic plant intoxication, Hyperparathroidism, renal failure, Johne's
Basically due to hypercalcaemia
Chronic dilation, healing ulcerative endocarditis, jet lesions.
Appears as firm white plaques in endocardium and intima of large vessels
Degenerative disease which accumulates mucin
Degeneration of valvular collagen - degenerative change in older dogs
Left ventricular endocardial fibroelastosis
Depositation of fibroelastic tissue on endocardium (due to deposition and poor lymph drainage in the myocardium)
Can result in decreased CO, CHF and left-bundle block
What bacterial species are associated with endocarditis?
Ecoli/ streps in dogs
A. pyogenes in cattle
Streps in pigs
Describe this lesion
Multifocal to coelescing rough, irregular nodules. Endocardium remaining is reddened.
Acute mf-c severe fibrinous endocarditis
Valvular injury leads to bacterial adhesion and proliferation.
Chronically fibrosis occurs
Sequelae to valvular endocarditis
Valvular dysfunction - regurgitation, systemic/ pulmonic hypertension
Atrial dilation and thromboembolism creation