5.2 Structural Heart Disease Flashcards
What medications will be prescribed for someone with aortic stenosis?
anti-hypertensive
ACE inhibitors
statins
What is structural heart disease?
A number of defects which affect the valves, chambers of the heart, and aorta.
Can be congenital or form later in life
What are some examples of congenital heart disease? (6)
atrial septal defect (ASD) ventral septal defect (VSD) coarctation of aorta patent foramen ovale (PFO) patent ductus arteriosus (PDA) tetralogy of fallot
What are some examples of heart disease that develops later in life? (2)
atrial stenosis/regurgitation (vascular dysfunction)
cardiomyopathy
What are the 7 phases of the cardiac cycle:
- Atrial Contraction
- Isovolumetric Contraction
- Rapid Ejection
- Reduced Ejection
- Isovolumetric Relaxation
- Rapid Filling
- Reduced Filling
What age group is most at risk of aortic stenosis?
70’s/80’s
What is aortic stenosis preceded by?
aortic sclerosis
What is aortic sclerosis?
aortic valve thickening without flow limitation
How do we confirm aortic stenosis?
echocardiography
When auscultating when would indicate the presence of aortic stenosis?
(early peaking)
systolic ejection murmur
What are some risk factors of aortic stenosis? (7)
hypertension high LDL levels smoking elevated CRP congenital bicuspid valves chronic kidney disease older age
What are some causes of aortic stenosis? (3)
rheumatic heart disease (most common in developing countries)
congenital heart disease
calcium build up
Which is the most common type of stenosis?
aortic stenosis
What is aortic stenosis?
When the aortic valve narrows which reduces or blocks blood flow from your heart into the aorta, (and so to the rest of your body)
How does rheumatic heart disease cause aortic stenosis?
An autoimmune inflammatory reaction is triggered by prior Streptococcus infection that targets the valvular endothelium, leading to inflammation and eventually calcification
How is aortic stenosis caused? (4)
- The valvular endocardium is damaged as the result of abnormal blood flow across the valve (in the case of bicuspid) or by an unknown trigger.
- Endocardial injury initiates an inflammatory process similar to atherosclerosis
- This leads to leaflet fibroids and deposition of calcium on the valve
- This progressively limits aortic leaflet motility
- -> STENOSIS
What abnormal physiology does aortic stenosis lead to?
Long-standing pressure overload –> left ventricular hypertrophy (LVH)
How does aortic stenosis lead to LVH?
Afterload remains the same despite increased pressure in the left ventricle caused by stenosis.
How does aortic stenosis lead to heart failure and which type?
Systolic function declines as wall stress inc., with resultant systolic heart failure
What would be the history and presentation of a patient with aortic stenosis?
exertional dyspnea and fatigue
chest pain
ejection systolic murmur
HO risk factors (rheumatic fever, age >65, CKD, LDL)
What investigations would we do for suspected aortic stenosis?
Transthoracic echocardiography
ECG and chest X ray (LVH)
Cardiac catherisation
Cardiac MRI
What is the primary treatment for patients with aortic stenosis?
Aortic Valve Replacement (AVR)
When is AVR recommended for patients with aortic stenosis?
symptomatic patients who LVEF <50%,
asymptomatic patients with rapid progression, abnormal exercise test, or elevated serum B-type natriuretic peptide (BNP) levels
What the alternative surgical treatment for aortic stenosis?
balloon aortic valvuloplasty
What type of aortic replacements can be implanted by transcatheter implantation device?
bioprosthetic
What is aortic regurgitation?
AR is the diastolic leakage of blood from the aorta into the left ventricle
Why does aortic regurgitation occur?
Due to incompetence of valve leaflets resulting from either:
- intrinsic valve disease
- dilation of the root
What are the two types of aortic regurgitation ?
chronic –> culminating into congestive cardiac failure
acute –> medical emergency, presenting with sudden onset of pulmonary oedema and hypotension or cardiogenic shock
What are some causes of aortic regurgitation> (5)
rheumatic disease infective endocarditis aortic valve stenosis congenital heart defects congenital bicuspid valves
What are causes of aortic dilation (which could subsequently lead to aortic regurgitation)? (5)
Marfan's Syndrome Connective tissue disease Ideopathic Ankylosing spondilytis Trauma
What type of hormone is vasopressin?
peptide hormone –> made from protein (9 aa)
What is the main function of ADH?
promote water reabsorption from collecting duct
Where is vasopressin stored?
posterior pituitary
Where is vasopressin produced?
hypothalamus, by neurones in supraoptic and paraventricular nuclei
Where are osmoreceptors?
hypothalamus
What will an increase in plasma osmolarity cause in terms of vasopressin?
simulate production and release
