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Left ventricular outflow tract (LVOT) obstruction is caused by a wide
range of different anatomical lesions, which are collectively referred
to as subaortic stenois (SS). SS can be isolated or associated with
other heart defects; in the most dramatic cases it can be part of a
syndrome that includes several obstructive lesions of the left heart,
called the Shone complex. Isolated SS can be caused by several factors:
displacement of the mitral papillary muscle, displacement of the
infundibular septum, abnormal insertion of the mitral valve or presence
of exuberant fibrous tissue [1].
Subaortic stenosis tends to evolve and progress over time even though
the speed of its progression is very variable and difficult to predict.
In addition to the risk of progression, patients with subaortic stenosis
face two other types of problems: an increased risk of infectious
endocarditis and aortic valve insufficiency if the fibrous strends
extend below the aortic valve cusps. The aortic valve may be normal or
stenotic. Subaortic stenosis, leading to a LVOT obstruction, causes an
increase in post-loadoing determining a concentrical ventricular
hypertrophy, especially at the septal insertion of the membrane [1].
SS is usually suspected in young adults when the valve anatomy is not
clearly stenotic, whereas Doppler examination reveals high transaortic
pressure gradient [2].
Concerning the surgical treatment of SS, many dilemmas still remain
open; it is uncertain which is the right timing and the type of
procedure, although it has been noted that an early intervention
decreases the risk of valve failure, even if the risk of stenosis
recurrence remains high in the long term period.
We report images from a case of subaortic stenosis in a 72 years old
woman referring to our Institution for exertional dyspnea (NHYA III).
The patient was successfully operated of subaortic membrane removal and
septal myectomy according to Morrow, the aortic valve was not surgically
treated as it was neither stenotic nor insufficient (Fig.1). The course
in the operating theatre was regular, the weaning from extracorporeal
circulation did not require any inotropic support. Respiratory weanig
and extubation occurred in the first few hours after arrival in the ICU.
The rest of the hospitalization in intensive care and cardiac surgery
ward was regular and free from major cradiovascular events. The patient
was discharged to a rehabilitation center on the fifth post-operative
days completely asymptomatic for angor and dyspnea (NYHA I) .