Optimum Antithrombotic Therapy Selection in Octogenarians and Nonagenarians Following WATCHMANTM Device Implantation

Background:
The WATCHMAN^TM device is as an alternative for patients with atrial fibrillation who are unsuitable for long-term anticoagulation. Optimum antithrombotic therapy (ATT) in octogenarians (≥ 80-89 years) and nonagenarians (≥ 90-99 years) with high bleeding risk is unknown.

Methods:
This is a retrospective study of 151 WATCHMAN^TM recipients at a tertiary cardiovascular center between 4/1/2015 and 9/27/2017. The primary outcome is the evaluation of the impact of ATT after WATCHMAN^TM on stroke, device related thrombus (DRT), and major bleeding events at 30±10-month follow-up.

Results:
A total of 151 patients underwent WATCHMAN^TM implantation between 4/1/2015 and 9/27/2017 in our cardiovascular center. A total of 48/151 (32%) were female with a mean age of 80±7.7 years, a mean CHA₂DS₂-VASc of 4.38±1.36, and mean HAS-BLED of 3.27±1.17. Octogenarians accounted for 65/151(43%), and nonagenarians for 16/151(10.6%), while 70/151(46%) of patients were < 80 years of age. ATT was different amongst age subgroups (p-value = 0.009, See Table 1). No ATT therapy was used in 1/65 (1.5%) octogenarian. There were no strokes reported at 30±10-month follow-up amongst all patients. No difference between patients < 80, ≥ 80-89, and ≥ 90-99 years was found in regard to incidence of major bleeding events, and DRT (p-values=0.0569, 0.116, respectively).

Conclusions:
For octogenarians and nonagenarians, a single antiplatelet agent is as effective as dual ATT in preventing stroke and DRT, with similar rate of major bleeding events.