Cardiovascular pathology 2 Flashcards
Heart Failure/Congestive Cardiac Failure (CCF)
Definition
Inability of the heart to pump enough blood needed to meet the metabolic demands of the tissue
Insidious effect =
chronic workload such as hypertension and valve diseases
Sudden effect =
acute haemodynamic stress such as fluid overload and large MI
Aetiology of heart failure
- Especially IHD and its causes
- Smoking, hypertension, diabetes
Pathogenesis of heart failure
- Increased cardiac work = wall stress
- Wall stress causes cells to stretch = Hypertrophy/dilation
Left sided heart failure clinical features
- Low cardiac output and hypoperfusion of tissues
- Pulmonary congestion causes pulmonary oedema and present of heart failure cells in alveoli
- Reduced kidney perfusion
Right sided heart failure clinical features
- Engorgement of portal and systemic venous systems
- Congestive splenomegaly, ascites, congestion and oedema of bowel wall
- Pleural and pericardial effusions
Valvular heart diseases
- Rheumatic heart disease - Aortic stenosis
- Disorders of valvular regurgitation
Problems with valvular opening =
stenosis
Acquired aortic stenosis (AS)
- Causes left ventricular hypertrophy (but no hypertension) and ischemia = cardiac decompensation, angina, CCF
Calcific aortic stenosis
- Most common valvular abnormality
- Consequence of age-related wear/tear
- If valve is bicuspid (congenital) – becomes stenotic earlier
- May involve mitral valve too
Acquired mitral stenosis (MS)
- Rheumatic heart disease
- Follows group A strep infection
- Diagnosis = Jones criteria
- Clinical features = mitral valve stenosis with infective endocarditis, Classical pancarditis
Aortic regurgitation
- Failure of valve to close properly = backflow = volume overload of heart
- May be due to RA, syphilis, Marfan’s syndrome
Mitral valve prolapse (MVP)
- Myxomatous degeneration of the mitral valve causing a “floppy valve”
- F>M
- Associated with connective tissue disorders e.g. Marfan’s
- Risk is sudden death from infective EC
Congenital Heart Diseases definition
- Abnormalities of the heart and great vessels present from birth
- May not be evident until adult life
Congenital Heart Diseases Aetiology
- Environmental factors = rubella, gestational diabetes of mother, teratogens
- Sporadic genetic abnormalities = Down’s syndrome, Turner Syndrome
Congenital Heart Diseases pathogenesis
faulty embryogenesis of heart (weeks 3-8)
Left to right shunts
- All have “D’s” in their name
- No cyanosis so live longer
- Pulmonary hypertension
Atrial septal defect (ASD)
- Abnormal atrial septum allowing communication of blood between the two atria
- Secumdum ASD = most common, arises from septum secundum
- Other types = primum (next to AV valves), sinus venosus
- Asymptomatic until adulthood
Ventricular septal defect (VSD)
- Most common CHD
- Often part of Tetralogy of Fallot
- 90% involve the membranous septum – 10% involve the muscular septum or lie under the infundibulum = “swiss cheese septum”
- Small ones often close spontaneously, large ones progress to pulmonary HT
Right to left shunts
- All have “T’s” in their name
- Cause cyanosis as deoxygenated blood bypasses lungs = systemic circulation
Tetralogy of Fallot
- Transposition of great arteries = truncus arteriosus,
- Total anomalous pulmonary venous connection,
- Tricuspid atresia (failure of formation of tricuspid valve)
Tetralogy of Fallot Clinical features
- VSD
- Sub-pulmonary stenosis – blockage of outflow of RV
- Aorta overrides the VSD
- RVH
Coarctation of aorta
- M>F (2:1)
- Females with Turner’s syndrome at risk
- Two forms = infantile and adult
- birth defect in which a part of the aorta is narrower than usual
Infantile form =
- Proximal to PDA, low pressure allows shunting of deoxygenated blood through PDA into circulation = cyanosis in lower half of body
Adult form =
- Closed ductus (no PDA), hypertension in upper extremities whilst hypotension in lower extremities and features of arterial insufficiency (claudication and coldness)
