Aortic valve defects Flashcards
Describe the aortic valve
It has three leaflets, the orificle is smaller, 3-4 cm2
What is aortic stenosis?
most common heart valve deformity, the valve is thickened and does not open properly
What are the common causes of aortic valve stenosis ?
degenerative as it is exposed to large pressures, rheumatic heart disease, congenital (bicuspid aortic valve)
Describe the degenerative causes of aortic valve stenosis
There is wear and tear caused by high pressures that the aortic valve is exposed to, this leads to inflammation, thickening and calcification of the cusps
Describe the physiological changes that occur in the heart in aortic stenosis
There is increased L ventricular pressure, ventricular hypertrophy (the size of heart muscle increases concentrically new sarcomeres are added in parallel, size of contraction increases, the volume decreases), more prone to ischaemia, LA pressure also increases and this can lead to pulmonary hypertension
Describe the progress of aortic stenosis
Slow progress, hypertrophy of LV, build up of pressure in LA, but when patients become symptomatic there is rapid deterioration, surgery needs to be performed within one month
What are he symptoms of aortic stenosis?
chest pain, syncope, dizziness, SOB on exertion, heart failure
What are the signs of aortic stenosis?
small volume and slow rising pulse, narrow pulse pressure, vigorous and sustained apex beat, LV heave, aortic thrill, signs of right sided heart failure , systolic murmur that radiates to carotids, crescendo descrescendo murmur
What are the investigations for aortic stenosis ?
ECG, chest X ray, cardiac catherisation, echo, cardiac MRI,
What is the treatment for aortic stenosis?
The treatment is limited to those who have cardiac failure, aortic valve replacement or rapid surgery
What is aortic regurgitation?
The aortic valve leaflets do not close properly and the blood leaks out from aorta to ventricles
What are the causes of aortic regurgitation?
aorta enlargement due to hypertension, connective tissue disorders, congenital bicuspid valves, rheumatoid arthritis, endocarditis, myxomatous degeneration
What are the pathological changes in aortic regurgitation?
Ventricles needs to cope with regurgitating blood, pressure and volume overload, this leads to dilation and hypertrophy of the ventricle,, more prone to ischaemia and can lead to LVF
What are the two types of aortic regurgitation ?
Acute and chronic, in chronic the patient can be asymptomatic as ventricle has time to adapt, SOB on exertion, in acute case there is no time for ventricle to adapt, it is an emergency
What are the symptoms of aortic regurgitation?
exertional dyspnoea, orthopnoea, paroxysmal nocturnal dyspnoea, palpitations, angina, syncope
What are the signs of aortic regurgitation ?
collapsing pulse, wide pulse pressure (high systolic and low diastolic ), hyper dynamic and displaced apex beat, strange BP, early diastolic decrescendo soft murmur
What are the investigation for aortic regurgitation?
ECG (ST/T changes), chest X ray (cardiomegaly), cardiac catherisation, echo, cardiac MRI
What is the treatment for aortic regurgitation?
vasodilators, more interventional treatment of repair or replacement surgery
What are the three most common valve problems?
senile aortic stenosis, bicuspid aortic stenosis, degenerative mitral stenosis
What are the two types of valves that can be used for surgery?
Prosthetic or animal valves
What are the advantages and disadvantages of animal valves?
patients do not have to be on warfarin, but they wear out quicker, usually used in older patients
What are the advantages and disadvantages of prosthetic valves?
They last longer, 3-40 years, but patients have to be on warfarin afterwards, can hear very load clicking sound
When should be aortic valve replaced?
In aortic stenosis if the symptoms are present. In aortic regurgitation if there is left ventricular dilation
When should be mitral valve replaced?
In mitral stenosis if the orificle is smaller than 1.5 cm2, in regurgitation based on the severity of the symptoms
