Lead insulation failure, a serious complication: risk factors and management

Abstract

We may divide abrasions according to mechanism into "outside-in" and "inside-out" abrasions. The "outside-in" abrasions are well known in the pocket as the result of friction between leads or between the lead and the device, as well as in the venous system, with tearing surfaces among leads, first rib, and clavicle. However, "outside-in" abrasions most frequently appear in the intracardiac part of the lead and are associated with infective endocarditis (IE) [2]. The outer insulation abrasion remains electrically signless unless concomitant inner insulation failure occurs and in the device control both oversensing and undersensing may be observed [3]. The Banacha classification was established to morphologically describe abrasions analysed with an optical microscope, and to facilitate comparison and analysis. The classification distinguishes three levels of silicone in vivo damage: mild, moderate, and severe, all in two subtypes: a and b [2]. A severe abrasion with conductor exposure may be assessed clinically (Fig. 1A) [4]. Insulation abrasion more often concerned patients with sub-pectorally or abdominally implanted devices. Risk factors of intracardiac abrasions are implantation of two or more leads in the heart cavities, and in the case of atrial leads: passive fixation, longer mean dwell time (time from implantation), and three or more procedures proceeding lead extraction [2]. Severe abrasions with conductor exposure were associated with the number of extracted leads, dwell time, location of the lead in the coronary sinus, and excessive lead length in the cardiac chambers [4]. The most important observation was that, irrespective of the abrasion level of degradation in the intracardiac part of the lead, they were associated with IE development [2]. The process of outside-in abrasion may be

Leads dislodged into the pulmonary vascular bed in patients with cardiac implantable electronic devices

“…Both mechanisms were related to lead fracture and displacement, excessive lead elongation due to pocket ligature failure, or non-functional lead abandonment after cutting the proximal ending of the lead. Previous studies revealed that lead loops determine intracardiac lead abrasion, which is a risk factor for LRIE development [11, 12, 18–20]. Our research showed a similar sequence of events in patients with LDPA.…”

Obserwacja długoterminowa u pacjentów z wszczepialnym kardiowerterem- -defibrylatorem i poddanych terapii resynchronizującej oraz bez niej

“…Electrical dysfunction is usually related to a conducting wire fracture in cases of low-voltage circuits, where it can lead to oversensing, inappropriate shocks, and loss of capture. High-voltage circuit failure can lead to short circuiting with a failure to defibrillate [24]. In the literature, we found the devices most prone to failure to be Fidelis and Riata leads, 28% versus 15% respectively [25,26].…”

Mechanical Behavior of Polyurethane Insulation of CRT Leads in Cardiac Implantable Electronic Devices: A Comparative Analysis of In Vivo Exposure and Residual Properties

“…MIO is a concern for both the inner surface of the outer insulation and, in general, for both the outer and inner surfaces of the inner insulation. This phenomenon impacts various layers of insulation, making it a critical consideration in the performance and safety of these medical devices [24]. Polyether polyurethane elastomers, despite not being biostable, remain in use due to their exceptional mechanical characteristics and biocompatibility.…”

“…Their continued application is recognized as being due to advancements in comprehending and managing the processes by which they degrade. These developments have allowed for more effective control over their degradation mechanisms, ensuring their viability for various applications [24]. Clinical research has investigated the factors that pose risks for lead damage, examined how lead failures manifest, and put forward strategies for their management.…”