LIMITATIONS IN THE USE OF SUBCUTANEOUS DEFIBRILLATOR IN PATIENTS WITH LOW BODY MASS INDEX

Abstract

Abstract Introduction Subcutaneous defibrillator is an effective and widely used tool in clinical practice but the presence of large fluctuations in the body mass index and the reduction of subcutaneous tissue may limit its application to all patients. Case Report In 2014, a 51–year–old woman underwent implantation of a dual–chamber transvenous defibrillator with left subclavian vein approach in secondary prevention for long Qt syndrome (LQT3). About 6 years after implantation she presented a ventricular lead breakage due to subclavian crush syndrome and was subjected to multiple inappropriate shocks due to lead failure. For this reason, the transvenous defibrillator was replaced with a single–chamber pacemaker for atrial stimulation and a subcutaneous defibrillator was implanted (Fig.1). In the following years the patient lost 14 kg and in the first months of 2022 she complained of the onset of stabbing pain in the precordial region near the upper face of the left sixth rib on the midclavicular line (Fig.2). Over the months, this symptomatology has become increasingly limiting and poorly responsive to normal analgesics but only to opiates; furthermore the pain has also occurred after a few weeks at the left parasternal level along the course of the distal portion of the subcutaneous catheter. For this reason, after discussing the case with the patient, we proceeded to implant a new transvenous lead via left subclavian vein and upgrade to a dual–chamber defibrillator. Subsequently, in the same operating session, the subcutaneous defibrillator was removed, finding only a modest traction resistance of the catheter in the parasternal area, resolved with the use of a 10 French introducer used as a sheet to debride the course of the same from the fibrotic adhesions (Fig .3). In the days following the procedure, the patient reported a progressive total disappearance of the pain symptoms. Reassessed after one year, the patient reports subjective well–being with total absence of chest pain and good quality of life. Conclusions The subcutaneous defibrillator represents an important resource for the management of the main ventricular arrhythmias, especially in patients with a high risk of infection and with a long life expectancy. The presence of a stable amount of subcutaneous tissue is a necessary condition to guarantee the tolerance of the lead over time and to avoid chronic pain situations that can lead to its removal.