Introduction
Leadless cardiac pacemakers (PMs) are an alternative to conventional transvenous PMs designed to avoid the need for transvenous leads and pockets 1. PM related adverse events remain substantial; they occur in 1 in 8 patients, despite advancements in pacing technology over the past six decades 2. Transvenous PM leads can undergo dislodgment, insulation failure, and may act as a portal for infection into the vascular space, whereas pacemaker pockets are susceptible to hematomas and infections3. Thus, the development of a pacing system foregoing leads and the need for a surgical pocket is a progressive advancement in pacemaker technology. This has been achieved following advances in pacemaker battery, component design and chemistry that have led to leadless pacemakers small enough to be placed directly in the heart; which may lead to the reduction in complications associated with conventional transvenous leads and pockets 4.
Leadless cardiac PMs are completely self-contained, encapsulated in a small unit, and are affixed by nitinol tines to the myocardium in the right ventricle through a minimally invasive transcatheter approach via the femoral vein. Reynolds et. Al and Reddy et. Al have reported two multi-center studies which have found leadless pacemaker implantation to be a promising alternative to older transvenous systems4,5.
The Micra transcatheter leadless pacing system (Medtronic, Minneapolis, MN); an example of such a leadless PM, has demonstrated high procedural success rates 6. However, the procedure may be associated with complications, these include traumatic cardiac injury with cardiac perforation and pericardial effusion, high capture thresholds, and rarely, ventricular arrhythmias 7,8. While some of these such as traumatic cardiac injury may be attributed to the learning curve of operators handling this novel technology, other complications such as arrhythmia may be secondary to implant position of the device 9.
Few cases of ventricular arrythmias due to Micra have been reported in the literature. We wish to add to the literature by presenting a case of ventricular fibrillation arrest temporally related to Micra implant.
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