TY  - CHAP
M1  - Book, Section
TI  - Bicuspid Aortic Valve
A1  - Shindler, Daniel M.
A1  - Shindler, Olga I.
A1  - Wright, Alicia
PY  - 2020
T2  - Practical Echocardiography for Cardiac Sonographers
AB  - Definition-  Bicuspid  aortic  valve:  two  instead  of  three  semilunar  aortic  valve  cusps.-  There  are  also  rare  patients  with  unicuspid  and  quadricuspid  aortic  valves.Cusp  nomenclature-  The  conjoined  cusp  is  usually  wider  than  normal  and  contains  a  raphe.-  Raphe:  a  ridge  that  extends  from  the  aortic  wall  to  the  commissure  of  the  conjoined  cusp.Raphe  height  variants-  No  evident  raphe,  just  a  “fishmouth”  systolic  opening.-  Shallow,  difficult-to-image  raphe.-  Classic  thick  visible  raphe.-  Unusually  tall  raphe—rising  as  high  as  the  free  edge  of  the  leaflets.Over  time,  the  raphe  may  become  calcified.  Calcification  is  manifested  on  echo  by  acoustic  shadowing  past  the  raphe.Classification:-  Type  1:  Fusion  of  the  right  and  left  coronary  cusp  (larger  sinus  diameter)  (70%–86%  incidence).-  Type  2:  Fusion  of  the  right  and  noncoronary  cusp  (associated  tubular  ascending  aorta  and  dilated  arch)  (12%–28%  incidence).-  Type  3:  Fusion  of  the  left  and  noncoronary  cusp  (rare  incidence).Imaging:-  Parasternal  long  axis  (PLAX)  view  provides  the  first  clue  to  the  presence  of  a  bicuspid  valve.-  Asymmetric  diastolic  leaflet  closure  line  located  on  an  “outside  third”  of  the  sinus  of  Valsalva  (Fig.  9-1).-  Systolic  doming.-  Diastolic  prolapse.Short  axis  (SAX)  view  is  used  for  definitive  diagnosis.  Sometimes  transesophageal  echocardiography  (TEE)  is  needed  for  confirmation.Diastole  may  fool  you:  The  closed  valve  may  look  perfectly  normal  on  echo  when  a  nonthickened  raphe  is  present.Look  for  a  thicker  than  normal,  partly  unseparated  raphe  in  systole.Look  for  the  systolic  “fishmouth”  opening.A  commissure  line  may  continue  “past  the  center”  without  bending.A  commissure  may  violate  the  10–2–6  o’clock  location.When  the  intercoronary  (right  to  left)  commissure  is  abnormal  (type  1),  the  systolic  opening  has  a  horizontal  orientation.When  the  right-to-noncoronary  commissure  is  abnormal  (type  2),  the  systolic  opening  has  a  vertical  orientation.Doppler  evaluation  of  the  systolic  gradient  in  bicuspid  aortic  valves:-  The  maximum  instantaneous  Doppler  gradient  is  typically  higher  than  a  peak-to-peak  gradient  measured  by  catheterization.-  The  mean  Doppler  gradient  is  closer  to  the  peak-to-peak  gradient  measured  by  catheterization.-  The  discrepancy  is  explained  in  some  cases  by  the  presence  of  pressure  recovery.-  Direct  planimetry  of  2D  and  3D  echo  images  should  be  done  when  feasible  (making  sure  the  smallest  possible,  “mouth  of  the  volcano,”  true  stenosis  orifice  is  used).-  In  children  with  a  stenotic  bicuspid,  or  a  unicuspid  aortic  valve,  the  presence  of  left  ventricular  hypertrophy  indicates  significant  valve  obstruction.-  Bicuspid  aortic  valve  is  associated  with  coarctation  of  the  aorta.  
SN  - 
PB  - McGraw Hill
CY  - New York, NY
Y2  - 2024/04/16
UR  - accesscardiology.mhmedical.com/content.aspx?aid=1175625628
ER  -