Implantation tools and techniques
While many of the fundamental aspects of device implantation are no
different when utilizing a lumenless lead, the process of placing the
lead in the desired location within the heart is fundamentally
different. When using a standard stylet-driven lead the stylet can be
withdrawn and shaped to allow the implanter to direct the lead. The
stylet is a stainless-steel wire (26-29 gauge) designed to direct the
lead tip by torquing the stylet wire within the lead inner lumen with
the stylet knob at the proximal end. The shape applied to the stylet is
critical to achieve the desired location. When implanting a lumenless
lead the implanter utilizes either pre-shaped or deflectable delivery
catheters to direct the lead. The intent of utilizing catheter delivery
is to provide increased control over positioning the lead tip in the
desired anatomical location. [10]. For right ventricular lead
placement, we target placement on the interventricular septum and mainly
utilize either a curved catheter with a short 90-degree secondary curve
(C315 His), a straight deflectable catheter with a short 90-degree
secondary curve (C304-HIS), or for large ventricles a straight
deflectable (C304-L69 and C304-S59) catheter. For atrial lead placement
we utilize either a J-shape catheter (C315J) or the straight deflectable
catheters mentioned above which can allow for placement on the
interatrial septum. These designs are intended to create the flexibility
for lead placement anywhere in the right atrium or ventricle. The
non-deflectable sheaths have an outer diameter allowing for introduction
through a 7F outer sheath while deflectable sheaths have an 8.4F outer
diameter and must be placed through a 9 F outer sheath. While the
delivery catheters can be placed directly into the vasculature, the
potential advantage of using an outer sheath is that it avoids the need
to regain vascular access should a lead become dislodged during or after
removal of the delivery catheter. While we recommend the routine use of
separate venipunctures, if an outer sheath is used, a second guidewire
can be placed into the outer sheath alongside the lead allowing for
retention of vascular access. For these reasons, we suggest the use of
an outer sheath when beginning to use the 3830 lead.