Discussion
The present case demonstrates that surgical epicardial LV lead
implantation could troubleshoot patients with limited and barely
acceptable LV pacing region transvenously which can progress myocardial
damage. Furthermore, to the best of our knowledge, this is the first
case report of an epicardial LV lead that was surgically implanted to
troubleshoot LV lead fracture.
The use of cardiac implantable electronic devices (CIED) as
nonpharmacological treatments has increased dramatically in the past
decade 7. Of the many possible complications following
CIED implantation, lead fracture is one of the serious mechanical
issues. Some studies have shown that the incidence of CIED lead fracture
is 1–4% 8, 9. There are various causes of lead
fractures, such as subclavian crush syndrome caused by continuous
compression of the lead between the clavicle and first rib; failure of
the lead itself; and flexibility of the lead—where bending within a
short radius of curvature exerts high stress on the metal components of
the lead 10, 11. In the present case, the subclavian
crush syndrome was possibly associated with the LV and atrial lead
fractures because both leads had been implanted via a left subclavian
veinous puncture and the fracture was detected in the subclavian region.
A recent study showed that CIED implantation via subclavian veinous
punctures is associated with a higher risk of lead failure compared with
cephalic vein cutdowns or axillary veinous punctures12. Therefore, a cephalic vein cutdown or axillary
veinous puncture can be considered to reduce the risk of LV lead failure
in CRT patients and avoid further CRT breakdown and worsening of HF.
LV lead fracture can be addressed via the new LV lead reimplantation
after the fractured LV lead extraction, or surgical epicardial LV lead
implantation. Although there are few data pertaining to LV lead
extraction for LV lead fracture, researchers have shown that
subsequent reimplantation after
the LV lead extraction is feasible ‘under local anaesthesia or sedation’
even with tools that are used in angioplasty in cases of CS adherences
or veinous occlusions as necessary 13. Due to its
invasiveness, the new LV lead reimplantation after the fractured LV lead
extraction can be the primary option to address the LV lead fracture of
CRT as compared to surgical epicardial LV lead implantation. However,
poor pacing threshold due to LV remodeling, anatomical abnormalities,
persistent diaphragmatic twitching due to unwanted phrenic nerve
stimulation, CS adherence after the lead extraction may cause an
implantation failure when adopting the transvenous approach13, 14. Therefore, all necessary precautions should be
observed through continuous monitoring for these complications.
Surgical implantation of an epicardial LV lead is an alternative option
to transvenous LV lead reimplantation. This can be performed with
concomitant open-heart surgery or by performing less invasive
left-lateral mini-thoracotomy. An advantage of surgical implantation is
direct access to the lateral LV wall 15, 16. Direct
visualisation of the region of interest greatly helps in achieving
optimal lead positioning regardless of the anatomy of the coronary vein.
Previous studies have shown that epicardial LV lead implantation results
in lower LV lead-related complication rates and positive long-term
clinical performance and durability, compared with transvenous LV lead
implantations 15, 16. Therefore, surgical epicardial
LV lead implantation, although more invasive than transvenous procedure,
can be feasible, at least in selected patients like the patient in the
present case 17.
The advantages of surgical epicardial LV lead implantation for
correcting LV lead fracture, as compared to transvenous LV lead
reimplantation after LV lead extraction, necessitates further
investigation. However, surgical epicardial LV lead implantation may be
favourable, particularly for those with difficulty of transvenous LV
lead replacement due to LV remodeling and anatomical limitation and for
those who are not expected to inhibit LV remodeling and hospitalisation
due to HF. As shown in this case report, poor pacing threshold due to LV
remodeling and diaphragmatic twitching of the entire LV lateral wall
inhibited a successful transvenous implantation of the LV lead into the
suitable region. In such case, surgical epicardial LV lead implantation
can troubleshoot LV lead fracture of CRT.