Murmurs Flashcards
What are the clinical signs in aortic stenosis?
Syncope
Chest pain
Breathlessness (on exertion)
What are the causes of aortic stenosis?
Bicuspid aortic valve
Age-related calcification
Rheumatic fever
What are the different survival rates depending on the presence of symptoms in aortic stenosis?
Asymptomatic = 1% chance of problems Symptomatic = 2-5 years before problems
What do you hear on auscultation for aortic stenosis?
Ejection systolic murmur
Radiates to the carotids
What are the signs of AS on examination?
Slow rising character of pulse
Low volume pulse
Narrow pulse pressure
Forceful apex beat
What can you see on x-ray with AS?
Dilated and prominent aorta
Relatively small heart
What can you see on ECG with AS?
Left ventricular hypertrophy
Left ventricular strain pattern (ST depression, T wave inversion in LV leads)
What is a murmur?
Sounds produced by turbulent flow of blood through the heart/abnormal valves.
How does inspiration help with identifying murmurs?
Deep inspiration means there is increased venous return to the heart. This means that it causes right sided murmurs to increase in intensity.
How does expiration help with identifying murmurs?
Deep expiration means there is an increased afterload from the heart, therefore causing left sided murmurs to be loudeste.g. - aortic stenosis and mitral regurgitation
Define stenosis
Obstruction to the normal flow of blood
Define regurgitation
Failure to prevent the back-flow of blood through the valve.
What can causes valvular disease?
Direct damage to the valve leaflets
Secondary to damage to the papillary muscles
What are the major causes of mitral stenosis?
Rheumatic fever- some people have calcification due to old age
What are the major causes of mitral regurgitation?
Rheumatic fever Mitral valve prolapse Papillary muscle dysfunction (post MI) Valve ring dilatation Cardiomyopathy Connective tissue disorders
What are the major causes of aortic regurgitation?
Rheumatic fever Aortic dilatation Rheumatological disorders Infective endocarditis Bicuspid valve
What occurs as a result of mitral valve calcification?
Calcification can causes stiffening of the valve cusps which leads to narrowing of the lumen. This narrowing leads to left ventricular hypertrophy as the muscle has to contract harder in order to force the blood through the narrowed lumen.
Define myxomatous degeneration
Degeneration of the connective tissue which holds the mitral valve in place. This occurs alongside a build up of dermatan sulfate (a glycosaminoglycan). This degeneration causes prolapse of the valve during systole, causing regurgitation.
Describe rheumatic heart disease
Occurs as a result of rheumatic fever - an autoimmune reaction caused by infection with group A streptococci, usually in the throat. Occurs in 5-15 year olds but is becoming rarer in the UK.
Where does rheumatic disease have an effect in the body?
Heart
Skin
Joints
CNS
What are some common symptoms with rheumatic fever?
Fever
Arthralgia
Leucocytosis
What is the pathophysiology of rheumatic disease in the heart?
Carditis which causes granulomatous regions in the heart with an area of central necrosis. Initially, there is infiltration of macrophages, lymphocytes and plasma cells. Eventually these will be replaced with fibrous tissue. There can be development of small nodules on mitral valve itself, made up of platelets a fibrin. They are known as Aschoff nodules which are areas of inflammation of connective tissue.
Describe infective endocarditis
Infection of the endocardium or vascular endothelium. Classed according to the causative organism.
Give some characteristics of the valves that are commonly affected by infective endocarditis
Previously damaged valves Valves with congenital abnormalities
