Leadless Pacemaker Implantation in a Patient With Diminutive Subclavian Veins

Background. Conventional pacemakers have a longstanding history of preventing morbidity and mortality in patients with bradyarrhythmia and conduction disorders. While decades of advancements have improved pacemaker technology and implantation technique, insertion of transvenous leads and formation of a pectoral pocket can lead to complications, including pocket hematoma, pneumothorax, or infection. Leadless pacemakers were introduced in 2012 to address these complications; however, early leadless systems only provided single-chamber ventricular pacing. In 2020, an accelerometer-based atrial sensing feature was developed to allow for atrioventricular (AV) synchrony with these devices. Early evidence suggests that patients with sinus rhythm and AV block can benefit from single-chamber leadless pacing systems with an AV synchrony algorithm. As availability of these devices continues to broaden, identification of appropriate recipients has become increasingly relevant.