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Successful percutaneous extraction of malpositioned pacemaker lead in the left ventricle after proper dabigatran treatment

Abstract Malpositioned pacemaker lead in the left ventricle (LV) is a rare procedural complication, which causes a special risk of thromboembolic events. Hence, prompt identification and early management of misplaced leads inside the LV is critical. Herein, we present a case of malpositioned pacemaker lead with transient ischemic attacks after the pacemaker implantation. The misplaced ventricular lead was discovered during regular echocardiography. Both leads were extracted percutaneously after dabigatran treatment. To our knowledge, this is the first report of uncomplicated percutaneous extraction of an inadvertently placed LV lead after dabigatran treatment. No neurologic events during a follow‐up of 4 years.


Misplacement of a permanent pacing lead in the left ventricle (LV)
is a rare procedural complication of transvenous pacemaker implantation, which causes special risk of thromboembolic events, ranging from mental confusion to cerebrovascular insults with permanent neurologic deficits. 1 Hence, prompt identification and early management of misplaced leads inside the LV is critical. Surgical removal of the lead was often considered to avoid the risk of left-sided endocarditis, ventricle perforation and systemic thromboembolism. Although there have been reports describing transvenous extraction of inadvertently placed LV leads, 1,2 it remains a debatable approach due to the risk of thromboembolic events during lead removal. 3 Direct oral anticoagulants are attractive alternatives for warfarin to treat left atrial (RA) and LV thrombosis. 4 We report a percutaneous extraction of misplaced pacemaker lead in the LV after proper pre-and post-operative dabiga-This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. © 2022 The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals LLC tran treatment without any complications. To our knowledge, this is the first reported such case.  A year later, the patient came to the out-patient clinic. She did not feel well and was very out of breath. She tried to keep going with different activities, but she felt her heart beating fast from time to time and then a pressure over her neck and chest. Pacemaker control showed 9000 short mode switch episodes which again looked like far-field R wave sensing. P sensitivity was lowered in the pacemaker. Six months later, the patient felt that she had become much worse over time, with worsening general weakness and more general discomfort with exertion-induced shortness of breath. She experienced repeated episodes of what could almost be described as aphasia, numbness in the left hand but also a feeling of tingling/rippling in the right forearm radially and down the hand, and sometimes bilateral

CASE REPORT
ailments.
An exercise test was performed, which showed ordinary exercise capacity and no chest pain. There was alternating atrial and ventricular pacing and sinus rhythm both at rest, before and after work.

DISCUSSION
Malpositioned pacing lead in the LV is a rare procedural complication, which was first reported by Stillman and Richards in 1969. 5  An RBBB pattern on a 12-lead surface ECG is a sensitive marker for a misplaced pacing lead in the LV and is often the first reason for suspicion. In our case, there was an RBBB appearance of the QRS complex before pacemaker implantation, while there was an RBBB in QRS both with pacing beats and non-pacing beats during exercise test after pacemaker implantation, which indicated a misplaced pacing lead in the LV.
In our case, however, the radiologist did not recognize the malposition suspicion in the routine chest X-ray and the physician did not mention the RBBB pattern in QRS with pacing beat during exercise test, which might be one of the reasons to delay the diagnosis of lead malposition.
TTE and TEE can also delineate the course of the lead accurately, although the acoustic shadowing may cause echo drop-outs. 9 With clinical suspicion, TTE and/or TEE can be a very useful tool to distinguish the misplaced pacing lead.
Pacemaker interrogations in our patient also showed frequent occurrence of far field sensing of R wave and mode switch episodes.
Far-field R-wave sensing has been identified as the most common cause of inappropriate mode switch in dual chamber pacemakers. However, whether the frequent occurrence of far field sensing of R wave in our case was related to left ventricular pacing is not determined.
A misplaced pacing lead in the LV can be complicated by thromboembolic events, 10  Transvenous lead extraction can be considered because it is a definitive solution for the problem with less trauma. However, perioperative prevention of the thromboembolic event is of critical importance.
There may be a risk of dislodging or stripping off thrombotic material from lead manipulation, especially with sheaths advanced over the lead into the left heart chambers during transvenous extraction. 11,12 In our case, dabigatran treatment pre-and post-operation; immediate preoperative TEE to rule out thrombosis; lowering the head side and giving heparin during operation; and no extraction sheath over the atrial septum to the left heart side, may have contributed the successful transvenous lead extraction without complications. If the pacing lead in the LV has been in place for a long time and a mechanical extraction sheath is needed to get into the left heart, we suggest an arterial cerebral protection system should be used. 2,3,13 Lessons we learned from this case are (a) the clinician should correctly recognize the suspicion of lead malposition in the routine chest X-ray after pacemaker implantation and on the ECG with an RBBB pattern in QRS during pacing; (b) if neurologic symptoms present after a device implantation, the case should be screened for proper lead placement; (c) in case that chest X-ray and/or an ECG could not rule out the suspicion of malposition, cardiac CT, TTE and/or TEE should be performed to delineate the course of the lead.
In conclusion, misplacement of RV pacing lead in the LV via a PFO is a rare but possible complication of pacemaker implantation. Dabigatran treatment pre-and post-operation, and no extraction sheath over the atrial septum to the left side, may be essential factors contributing to our successful transvenous LV lead extraction without complications.

ACKNOWLEDGEMENT
The study was partially supported by funding from Eva and Carl-Eric Larsson foundation.