Aortic regurgitation
Etiology and pathology
Valvular disease
Common causes-
Rheumatic
Bicuspid aortic valve
Calcific aortic valve disease (usually AR is mild)
Infective endocarditis (cusp damage, vegetation interfering with coaptation)
Trauma (ascending aortic tear causes cusp prolapse)
Large VSD
Membranous subaortic stenosis
Less common causes-
After percutaneous balloon valvulotomy
Myxomatous degeneration of aortic valve
Congenital AR- unicommissural, quadricuspid
Rupture of congenitally fenestrated valve (usually due to hypertension)
Connective tissue disease- SLE, RA, AS, Takayasu, Whipple, Crohn, Jaccoud arthropathy
Anorectic drugs
Aortic root disease-
Root dilation-
Marfan syndrome
Cystic medial necrosis other than Marfan
Bicuspid aortic valve
Syphilis
Hypertension
Age related
Connective tissue disease- ankylosing spondylitis, osteogenesis imperfecta, Behcet syndrome, psoriatic arthritis, ulcerative colitis with arthritis, relapsing polychondritis, reactive arthritis, GCA
Appetite suppressants
AR itself may increase AR due to ascending aortic dilation- AR begets AR
Root dissection
Chronic AR
Pathophysiology
Preload is increased due to-
Increased EDV
(Note- Preload is the tension in the myocardium just before contraction- correlates with EDV)
(Note- Tension from Wikipedia-In physics, tension is the magnitude of the pulling force exerted by a string, cable, chain, or similar object on another object. It is the opposite of compression. As tension is the magnitude of a force, it is measured in newtons and is always measured parallel to the string on which it applies)
Afterload is increased due to-
Increased LV systolic pressure and
LV dilation
(Note- Afterload is the tension in the myocardium during contraction- it is proportional to PR/h where P is ventricular pressure, R is radius of ventricle and h is wall thickness)
Myocardial ischemia occurs due to-
Increased myocardial oxygen demand due to-
Increased afterload
Increased LV ejection time
Increased LV mass
Decreased myocardial oxygen supply due to-
Decreased aortic diastolic pressure
Decreased diastolic filling time due to increased LV ejection time
