| What are the aortic valve diseases? | Aortic stenosis and Aortic regurgitation. |
| What are the etiologies causing aortic stenosis? | Congenital (Bicuspid -most common heart valve defect, or Unicuspid valve)
Degenerative Calcification
Rheumatic Fever
Radiation |
| How is the pathogenesis of AS? | degenerative calcification of aortic cusps occurring on a substrate of congenital defect, chronic deterioration (trileaflet) and previous rheumatic inflammation
It is not a passive process, features include vascular atherosclerosis, endothelial dysfunction, lipid accumulation, inflammatory cell activation, cytokine release and upregulation of signaling pathways. |
| How is the progression towards AS? | Risk factors include (genetics, older age, male sex, comorbidities, smoking, increased serum phosphate)
this will lead initially into aortic sclerosis (by stress or inflammation preceding lipid inflitrates and myofibroblast differentiation)
Then this will lead to aortic stenosis, first with progressive disease (by oxidative stress, increased Angiotensin II), then finally leads to aortic obstruction (hydroxyapatite nodules and cartilage and bone formation) with age |
| What are risk factors associated with development and progression of calcific AS? | high LDL, Lpa, DM, smoking, chronic kidney disease, metabolic syndrome |
| How is the pathophysiology of AS? | Obstructing LV outflow causes pressure gradient between aorta and LV, resulting in mean systolic pressure gradient >40 mmHg (between aorta and LV) with normal CO or aortic orifice area <1cm2. (leading to increased blood velocity through the valve |
| What are the complications associated with calcified aortic valve? | Pulmonary HTN, diastolic dysfunction, reduced LV systolic function, LV hypertrophy, myocardial fibrosis, reduction coronary flow reserve. |
| What is the natural history of AS? | Valve area decrease 0.1-0.3 cm2/year, systolic pressure gradient increases 10-15 mmHg/year, we can't predict rate of progression, average survival after symptoms is 2-3 years.
severe AS can cause sudden death (rarely without any prior symptoms) |
| What are the symptoms of AS? | Rarely clinical if aortic valve >1cm2.
Three cardinal symptoms are exertional dyspnea, angina pectoris and syncope |
| What are the physical findings if AS? | Regular rhythm, normal systemic arterial pressure, thrill or shudder palpable over carotid arteries (left).
Systolic ejection murmur (after S1) increases intensity to reach a peak in middle of ejection, low pitched, rough and loudest at heart base (second right intercostal space) (grade III/VI |
| How is the initial evaluation of AS? | Pt with physical findings should undergo ECG, chest X ray. |
| What are the findings in TTE of AS? | ECG confirms it, assesses valve calcifications, LV functioning, wall thickness, and detects other valve disease. |
| What are the classifications of severity of AS? | Mild (10-20 mm area>1.2 cm2)
Moderate (>20mm, area<1.2 cm2)
Severe (>40mm, <1cm2) |
| What are serial testings of AS (follow up)? | ECG (if severe every 1 year, if moderate every 2 year, if mild every 5 years)
ECG should be done whenever there is a change in clinical findings. |
| What are the indications of cardiac catherterization? | Recommended before any surgery, in pt with:
history of CVD, suspected MI, LV systolic dysfunction, Men>40 and postmenopause, CVD risk factors, secondary MR. |
| What are the Abx prophylaxis that should be taken? | Should be considered for high-risk procedures, pt with prosthetic valves, pt with infective endocarditis, standard invasive procedure measures, considered in dental procedures... |
| What is the medical treatment of AS? | Asymptomatics don't have any medication, symptomatics need surgery not medication
Most patients with moderate or severe AS should be advised to restrict physical activity |
| How is aortic valve replacement? | Recommended for severe AS, asymptomatic with severe AS and systolic LV dysfunction or demonstrable symptoms on exercise testing |
| What are the modes of interventions of AS? | We have two choices (surgical and transcatheter intervention) choice is according to clinical, anatomical, procedural team factors and risks and benifits ratio.
Low-risk young pt <75 yrs or unsuitable for TAVI transfemoral (SAVR)
Older pt, high risk pt unsuitable for surgery (TAVI)
remaining pt both procedures are recommended
SAVR recommended also for severe AS undergoing CABG or surgical intervention on ascending aorta |
| What are the etiologies of aortic regurgitation? | Valvular (congenital (bicuspid), endocarditis, myxoma, RF, traumatic, syphilis, SpA)
Root disease (aortic dissection, cystic medial degeneration, Marfan's, non-familial aneurysm, bicuspid aortic valve)
Aortitis
HTN |
| How is the pathophysiology of aortic regurgitation? | Causes myocardial ischemia by decreased consumption, decreased stroke volume, decreased diastolic pressure, and left ventricular volume. |
| What is the natural history of AG? | 3/4 of pt are men, but primary valvular AR associated rheumatic mitral valve disease.
Acute AR seen in infective endocarditis, aortic dissection, and trauma. |
| Talk about acute AR. | LV cannot dilate and maintain SV, diastolic pressire of LV then rises with elevation of LA and PA wedge pressure, causing pulmonary edema and cardiogenic shock. |
| Talk about chronic AR. | May be asymptomatic for 10-15 years, associated with exertional dyspnea, diminished cardiac reserve, orthopnea, paroxysmal nocturnal dyspnea, and excessive diaphoresis.
Also angina pain could occur, even in younger patients, and may develop at rest or at motion. |
| What are the physical findings in severe AR? | Widened arterial PP of systolic and diastolic pressure, displaced LV laterally and inferiorly, a diastolic thrill may be palpable along left sternal border in thin-chested people, and a systolic thrill in suprasternal notch and towards carotid arteries.
Aortic valve closure sound (A2) is absent.
High-pitched decrescendo diastolic murmur heard best in third intercostal space along left sternal border. |
| What are the physical findings in mild AR? | Brief murmur holodiastolic (increases with severity)
Mid-systolic ejection murmur audible in isolated AR heard at heart base transmitted along carotid artery.
Austin-flint murmur (third murmur soft low pitched diastolic murmur, sometimes heard in AR) |
| What are the lab findings of TTE in AR? | TTE is used to Describe valve anatomy, quantify aortic regurgitation, evaluate its
mechanisms, define the morphology of the aorta, and determine the
feasibility of valve-sparing aortic surgery or valve repair.
at 4 levels annulus, sinuses of Valsalva, sinotubular junction, and tubular
ascending aorta
early detects change in LV size and function |
| What are other lab findings seen for AR? | TEE
CMR should be used to quantify the regurgitant fraction when echocardiographic
measurements are equivocal or discordant with clinical findings
CCT is recommended to assess the maximum diameter at four levels in patients
with aortic dilatation |
| What are the measures taken before deciding treatment options? | Keep in mind that chronic AR pt don't have symptoms unless exists myocardial dysfunction and when delayed too long surgery doesn't restore LV function.
so chronic AR need follow up and ECG done every 6-12 months if operation is necessary at optimal time (after LV dysfunction and prior to development of severe symptoms) |
| What are the operations done for AR? | It can be deferred as long as the pt is asymptomatic with normal LV function without severe chamber dilation.
AVR indicated for severe AR symptomatic individuals irrespective of LV function.
Operation should be carried out in asymptomatic pt with severe AR and progressive LV dysfunction. |
| What is the indication for surgery in AR? | Symptomatic pt, asymptomatic pt with LVESD >50 mm/ >25 mm/m2 BSA (small body size pt) or resting LVESD<50%, and symptomatic and asymptomatic pt with severe aortic regurgitation undergoing CABG or surgery of ascending aorta/other valve |
| When is aortic root/tubular ascending aortic aneurysm recommended? | Valve-sparing aortic root replacement is recom- mended in young patients with aortic root dila- tion, if performed in experienced centres and durable results are expected Ascending aortic surgery is recommended in patients with Marfan syndrome who have aortic root disease with a maximal ascending aortic diameter ≥50 mm. |
| Give the algorithm of treating AR? | . |
