LP implantation in octogenarians
A previous report from Micra post-approval registry proposed octogenarians with an age of more than 85 years old as a risk factor for a perforation during LP implantation. 12 They proposed that most patients who developed perforations had more than 1 risk factor including an older age, low BMI, female sex, congestive heart failure, non-AF indication, and chronic lung disease. However, although the number is small, our experience suggested a safety profile of LP implantations even in octogenarians. Furthermore, all patients could achieve successful deployment with only 1 or 2 device deployment attempts. There might be one explanation supporting this favorable outcome. In this cohort, 4 of 8 patients (50%) had AF including 3 with permanent AF and all these patients had a giant left atrium with a left atrial dimension of more than 50mm. Furthermore, 5 of 8 patients (63%) had moderate or severe tricuspid valve regurgitation (TR), suggesting an right atrial volume overload. The previous transvenous leads might help worsening the severity of the TR owing to the mechanical interferences with the tricuspid valve closure. 23 These anatomical remodeling in the right atrium might allow for a safer manipulation of the LP catheter system. 12
The LP may have several advantages in considering it as a re-implantation strategy in octogenarians. First, the small surface area, occurrence of LP encapsulation, and location completely within the intracardiac space, could lead to a potential benefit in preventing a relapse of an infection. 24 Second, patients with dementia may have the risk of self-manipulation of the pacemaker pulse generator within the pocket resulting in pocket trouble.25 Furthermore, patients with severe frailty might have the risk of skin thinning that could cause a generator exposure. The use of a small intracardiac LP eliminates all risks of pocket trouble and infections and the necessity of infection-prone pectoral generator replacements. 11, 12 Third, in our cohort, 6 of 8 patients (75%) had ipsilateral subclavian vein occlusions in the preprocedural venography. Re-implantation of a PM without using the collateral subclavian vein may have been of benefit, especially in patients who had a risk of future hemodialysis considering a patent vascular access.