On-X Ascending Aortic Prosthesis, Инструкция по эксплуатации

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On-X
®
Ascending Aortic Prosthesis IFU 13
English
Aortic replica sizers are provided for all aortic valve sizes. For size 19 mm
through 25 mm aortic valves, the aortic replica sizers are used to verify that
the aortic valve can be properly seated in the annulus and that the coronary
arteries remain unobstructed. Size 19 mm through 25 mm aortic valves are
designed to fit within the annulus at implant such that the exposed carbon
flare rests in the annulus and the sewing ring is intra-supra annular.
WARNING: Do not size the sewing cuff of the size 19 mm through 25
mm aortic valve to fit within the annulus. Size 27/29 mm aortic valves are
designed to be placed in an intra-annular position and have a replica sizer
to mimic this placement.
9.5 Valve Suturing Techniques
Valve suturing techniques vary according to the preferences of the implant-
ing surgeon and patient condition. The aortic valve is designed to have
the tissue annulus about the orifice flare. The general consensus among
surgeons is that a non-everting interrupted mattress suture technique, with
or without pledgets, provides the best conformation of the valve annulus to
the outer surface of the flare.
Sutures should be passed through the midpoint of the sewing cuff. This
allows the sewing cuff to remain flexible and conform to the annulus. It also
prevents the suture needle from contacting the titanium rings that lie within
the sewing cuff. The orientation marks on the sewing cuff may be used to
aid in suture placement.
When all sutures are in place, the prosthesis is advanced into the annulus
and the sutures are tied down. It is suggested that the first 3 knots be
tied equidistant to one another and midway between the commissures to
stabilize the valve in the annulus. The holder handle is removed from the
valve by carefully depressing the plunger in the holder handle as shown in
Figure 8, then gently lifting the holder handle out of the valve/prosthesis.
WARNING: Do not attempt to reinsert the valve holder handle into the
valve once it has been removed. Doing so could damage the valve and
cause catastrophic failure of the valve or harm to the patient.
9.6 Graft Length and Suturing
The graft portion of the prosthesis may be trimmed at any time during the
implant procedure to the appropriate length.
CAUTION: Clamping may damage any vascular graft. Handling of the graft
must be gentle and minimized in order to prevent loss of gelatin coating.
CAUTION: Excessive tension on the graft should be avoided.
CAUTION: The use of round taper point needles minimizes graft damage.
When de-airing through the graft, a 19-gauge needle is usually sufficient.
Cutting point needles should be avoided to prevent damage.