aortic stenosis

CJ

1 Aortic Stenosis

Aortic Stenosis (AS) can be characterized by the Obstruction of blood flow across the Aortic Valve. 3 main Causes Of Valvular Aortic Stenosis are Congenital Calcific Rheumatic Congenital unicuspid Valve Bicuspid Valve calcific due to Age Related Degenerative changes Rheumatic Disease usu­ally coexisting with Mitral Valve Disease ^^Clinical Features:^^ Murmur Type: Systolic Murmur (between St and S2). Heart Sounds: Sj—Usually normal. S2—Soft Aj (reflecting the immobile Aortic Valve) followed by a P2. With increasing severity ofthe AS, a delayed Aortic Valve clo­ sure can cause the P2 to precede the \ _resulting in a paradoxical split S2. As the Aortic Valve becomes more stenotic, the \ _may disappear, resulting in a single S2 (ie, just a P2). S.—S. can be heard, which reflects Atrial Contraction into a 44stiffened ventricle (ie, LV Hypertrophy). Murmur sound A systolic crescendo-decrescendo “ejec­tion” murmur (ie, “harsh” quality) can be best heard over the right second intercostal space with Radiation that is trans­mitted equally over both carotid arteries. => ^^Aortic Stenosis^^ In Elderly patients, the murmur may radiate to the Apex instead of the carotids, which may be misinterpreted as Mitral Valve Regurgitation (Gallavardin phenomenon). On palpation ofthe Carotid Artery, a diminished and delayed (parvus et tardus) carotid upStroke is a classic finding in Severe Aortic Stenosis]], but may be masked in Elderly patients who have stiffened carotid ves­sels. The intensity of the murmur will change upon different Maneuvers (see Table 3-6).

Severity: In adults, the normal Aortic Valve area is between 3 and 4 cm2 with a mean gradient <5 mm Hg and an Aortic jet velocity of <2 in/sec. The severity of the Stenosis can be classified as mild Stenosis (Valve area >1.5 cm2, mean gradient <25 mm Hg, Aortic jet velocity <3 m/sec), Moderate Stenosis (Valve area 1.0-1.5 cm2, mean gradient 25-40 mm Hg, Aortic jet velocity 3-4 m/sec), Severe Stenosis (Valve area <1 cm2, mean gradient >40 mm Hg, Aortic jet velocity >4 m/sec), and critical Aortic Stenosis (Valve area <0.75 cm2 and/or Aortic jet velocity >5 m/sec). It should be noted that there is variability between symptoms and the severity of the Stenosis (eg, patients classified with Severe Stenosis may have little to no symptoms and vice versa

^^Clinical Progression: ^^ As the Aortic orifice area becomes Smaller and a Pressure gradient begins to develop, the outflow obstruc­tion leads to an increase in left ventricular systolic Pressures. The Left Ventricle is able to compensate by increasing the wall thickness (ie, Concentric Hypertrophy). The wall thickness can now reduce the wall stress (Laplace’s law) and ventricular func­tion can be preserved with the patient being asymptomatic for a prolonged period. At some point, the left ventricular func­tion becomes maladaptive and LV function begins to decline. Patients with advanced Aortic Stenosis can present with the classic symptoms, which can be easily remembered by the mnemonic “SAD” or Syncope, Angina, and Dyspnea (ie, Heart failure).

3am Progressive narrowing of the aortic valve, usually as a result of wear and tear (calcific degeneration). Hx:  Syncope, Dyspnea + angina the classic triad, palpitations Ex:  Ejection systolic murmur (crescendo-decrescendo) Ix:  TTE / TOE Mx:  Rx: ↑CO, ↓TPR; Surgical: Balloon Valvuloplasty → bioprosthetic / metallic valve replacement Aortic Stenosis