Inappropriate Shock Due to Subcutaneous Lead Body Fracture: Extraction and Reimplantation

Case Report

Austin Cardio & Cardiovasc Case Rep. 2023; 8(1): 1052.

Inappropriate Shock Due to Subcutaneous Lead Body Fracture: Extraction and Reimplantation

C Moïni1,2,4; D Rahim2; N Belfeki3; A Lefoulon1; D Poindron4; N Lellouche5

1Department of Cardiology, GHSIF, Melun, France

2Department of Cardiology, Antony Private Hospital, France

3Department of Internal Medicine, GHSIF, Melun, France

4Department of Cardiology, Les Fontaines Clinic, Melun, France

5Department of Cardiology, Henri Mondor University Hospital, Creteil, France

*Corresponding author: Cyrus Moini Department of Cardiology, GHSIF, Les Fontaines Clinic, Melun and Antony Private Hospital, France. Email: cyrus.moini@ghsif.fr

Received: March 21, 2023 Accepted: April 26, 2023 Published: May 03, 2023

Abstract

Subcutaneous Implantable Cardioverter Defibrillator (S-ICD) has been developed as an alternative to Transvenous (TV) devices to reduce lead-related complications leaving the heart and vasculature untouched.

Recently, Boston Scientific published a safety notice in December 2020 regarding a subcutaneous electrode risk of fracture. In the following case report, we describe a case report experiencing this complication and present how we proceeded for lead extraction and reimplantation. The procedure remained safe and easy.

Keywords: Lead fracture; Subcutaneous ICD; Extraction

Introduction

The Implantable Cardioverter Defibrillator (ICD) has proven to be an effective strategy for sudden cardiac death prevention in patients with life-threatening ventricular arrhythmia. However, the Transvenous (TV) lead remains the Achilles’ heel of classical ICD systems (conductor fracture, insulation abrasion, extraction risk, infection …). TV lead-related complications could reach 20% in 10-year-old leads in young and active patients [1]. The S-ICD has been developed in response to these concerns.

However, Boston Scientific recently published a safety notice in December 2020 regarding a risk of body lead fracture of the subcutaneous electrode [2] (FDA class I recall). To date, 68 cases of lead fracture have been reported worldwide with an evaluated occurrence around 0.30% at 66 months [3]. According to the information provided by the company and the literature [4,5], fractures are located immediately after the distal part of the proximal electrode. This specific area is filled with adhesive during assembly and allows the connection of the conductor to the proximal sensing electrode. Fractures are described by strictly similar primary and secondary vectors; flat alternate vector; system impedance greater than 400 ohms causing beeping tones of the ICD.

If the vector is programmed to secondary or alternate sensing, warning/precursor signals of the fracture might be stored, showing non physiological mechanical artifact.

Case

In July 2020, a 58-year-old man with an ischemic cardiomyopathy was implanted with an S-ICD in secondary prevention. 23 months later, the S-ICD delivered a therapy at night and the patient was called for follow-up. The examination revealed a high electrode impedance (>400 ohms) and 3 episodes classified as “ventricular tachycardia” of which one was treated.

The 3 events showed mechanical artifacts. S-ECG control reveals identical primary and secondary vectors and a flat alternate vector (Figure 1). Chest X-ray with front and left profile confirmed the lead rupture at the left xypho-sternal angle as described in the literature. The patient was asymptomatic and did not report any chest trauma.