Valvular heart disease Flashcards
(36 cards)
What are the causes of aortic valve stenosis?
- aortic valve sclerosis -> calcification & fibrosis of leaflets
- bicuspid aortic valve -> congenital valve malformation
- rheumatic fever -> commissural fusion
What is the pathophysiology of aortic valve stenosis?
1- fibrosis & calcification of valve
2- impeded blood flow through valve ————-> murmur/syncope
3- LV contracts harder to push blood against stiff valves
4- high LV-aorta pressure gradient drives blood into aorta to maintain CO (initially)
5- concentric hypertrophy —————————–> angina
6- stiff, hypertrophied LV & high LV pressure makes it harder to fill -> decreased CO (HFpEF)
7- pulmonary congestion ——————————> HF/dyspnea
What are the symptoms of aortic stenosis?
SAD
- Syncope
- Angina
- Dyspnea on exertion (HF like symptoms) orthopnea, PND
What are the clinical features of aortic stenosis?
- Crescendo-decrescendo systolic murmur -> at the 2nd right intercostal space -> radiates to carotid arteries
- handgrip increases intensity of murmur
- valsalva decreases or doesnt change the intensity of the murmur
- soft S2
- S4 if disease if progressive
- pulsus parvus et tardus
- precordial thrill
- early systolic ejection click
How is aortic valve stenosis diagnosed?
ECHO (diagnostic)
- calcification & narrowing of aortic valve
- increased mean aortic pressure gradient & transvalvular velocity
ECG
- signs of LVH (non specific)
CXR
- calcific aortic valve
- enlarged LV
- signs of heart failure
Cardiac catheterization (definitive diagnostic) - used in patients who echo is non-diagnostic
How is aortic valve stenosis managed?
- surgical aortic valve replacement
- transcatheter aortic valve replacement TAVR
What is the age of onset of aortic valve regurgitation?
40-60
- severity increases with age
What are the causes of aortic valve regurgitation?
PRIMARY VALVULAR DEFECT
- congenital bicuspid valve
- calcific aortic valve disease
- rheumatic heart disease
AORTIC DILATATION
- connective tissue disorders (Marfan or Ehlers-Danlos)
- chronic hypertension
- aortitis
- thoracic aortic aneurysm
What is the pathophysiology of acute aortic valve regurgitation?
increased systolic pressure & decreased diastolic pressure
1- LV cant dilate enough in response to regurgitant blood
2- LV end-diastolic pressure increases rapidly
3- pressure transmits backward into pulmonary circulation -> pulmonary edema & dyspnea
- cardiogenic shock & myocardial ischemia if severe
What is the pathophysiology of chronic aortic valve regurgitation?
increased systolic BP & decreased diastolic pressure
1- compensatory increase in stroke volume maintains CO
2- increased left ventricular end-diastolic volume
3- LV enlargement & eccentric hypertrophy
4- left ventricular systolic dysfunction
What are the clinical features of aortic valve regurgitation?
- dyspnea on exertion, PND, orthopnea
- palpitations
- angina
- cyanosis & shock in ACUTE (emergency)
- symptoms of underlying disease (fever in infective endocarditis)
- HIGH PITCHED BLOWING DECRESCENDO DIASTOLIC MURMUR -> heard in the left 3rd & 4th intercostal spaces
- > increases with squatting & handgrip - S3
- widened pulse pressure
- Quincke sign -> visible capillary pulse when pressure applied to fingertips
- De Musset sign -> rhythmic nodding of head in sync with heartbeats
- Corrigan pulse (water-hammer pulse)
- in chronic -> displaced PMI
What are the investigations used to diagnose aortic valve regurg?
ECHO -> dilated aortic root & reversal of blood flow in aorta
XRAY -> to assess pulmonary edema & rule out other causes of dyspnea
- acute AR -> congestion
- chronic AR -> left ventricular hypertrophy + congestion
How is acute aortic valve regurg managed?
- severe acute AR -> surgical treatment ASAP
- medical management of complications
How is chronic aortic regurg managed?
- surgery -> for symptomatic AR & severe asymptomatic AR
- medical management for comorbidities
What is the most common cause of mitral valve stenosis?
rheumatic fever
- onset of symptoms between 20 - 39 years
- impairs blood flow from the left atrium to the left ventricle
What is the pathophysiology of mitral valve stenosis?
1- obstruction of blood flow into the left ventricle (decreased end-diastolic LV volume)
2- decreased SV & cardiac output (forward heart failure)
3- increase in left atrial pressure
4- increased pulmonary capillary pressure -> cardiogenic pulmonary edema
5- pulmonary hypertension -> backward failure & right ventricular hypertrophy
What are the clinical features of mitral valve stenosis?
- dyspnea
- fatigue
- hoarseness
- dysphagia
- palpitations
- mitral facies
- irregular heart rhythm secondary to atrial fibrillation
later stages - symptoms of right heart failure/pulmonary HTN
- paroxysmal nocturnal dyspnea
- orthopnea
- hemoptysis
What will be heard on auscultation of mitral valve stenosis?
- diastolic murmur -> heard at 5th left intercostal space at midclavicular line
- loud S1
- opening snap
What diagnostics are used for mitral valve stenosis?
ECHO -> most important to confirm diagnosis
- left atrial enlargement
- thick calcified mitral valve
- fish mouth appearance of orfice
ECG
- P mitrale: left atrial enlargement
- atrial fibrillation
- right ventricular hypertrophy
XRAY
- left atrial enlargement
How is mitral valve stenosis managed?
- no therapy in asymptomatic patients
- medical therapy in case of mild symptoms -> diuretics for pulmonary congestion & edema -> B blockers to decrease heart rate
- surgical treatment if severe symptoms
What are the causes of mitral valve regurgitation?
PRIMARY MR (organic)
- degenerative mitral valve disease
- rheumatic fever
- infective endocarditis
- ischemic MR
SECONDARY MR (functional) - dilated cardiomyopathy
What is the difference between acute & chronic mitral regurg?
ACUTE
- abrupt elevation of left atrial pressure in setting of normal LA size & compliance
- backflow into pulmonary circulation
- CO decreases due to decreased forward flow
CHRONIC
- gradual elevation of left atrial pressure in the setting of dilated LA & LV
- LV dysfunction occurs due to dilation -> HF
What are the clinical features of mitral valve regurgitation?
- dyspnea on exertion
- PND
- orthopnea
- palpitations
- pulmonary edema
- dry cough
- fatigue
What will be heard on auscultation of mitral valve regurgitation?
HOLOSYSTOLIC MURMUR (high pitched blowing) -> radiates to left axilla & heard best over apex
- > intensity can be increased by increasing preload (leg raise) or afterload (handgrip)
- diminished S1
- S3 gallop
- laterally displaced PMI
