Introduction: Delayed high-grade atrioventricular block (H-AVB) following transcatheter aortic valve replacement (TAVR) has been reported, but identification of such patients post-discharge (DC) has not been well studied. We assessed the utility of ambulatory event monitoring (AEM) in identifying such patients and risk factors.
Methods: Patients undergoing index TAVR at our institution from October 2016-May 2017 without a preexisting pacing device and without pre-discharge H-AVB necessitating permanent pacemaker (PPM) implantation were discharged with 30-day AEM. Baseline, procedural, and follow-up data were collected and compared among those with and without subsequent need for post-discharge PPM.
Results: Among 59 patients undergoing TAVR, 11 had prior PPM or ICD, and 6 required pre-DC PPM implant for H-AVB; 40 were discharged with 30-day AEM. Six (15%) developed H-AVB (3 Mobitz II 2nd degree AVB, 3 complete AVB) at a median (range) of 5 (4-24) days post-TAVR. There was no statistically significant difference in age, gender, or TAVR valve type between those with or without need for post-DC PPM, although 67% of the subjects presenting with late H-AVB had Edwards Sapien 3® valve, vs. 33% with Edwards Evolut® implanted (Figure, A). Presence of right bundle branch block (RBBB) at baseline was significantly associated with late H-AVB presentation (Figure, A). While 50% of subjects developed change from baseline AV conduction, this was not significantly associated with post-DC H-AVB (Figure, A). Those developing H-AVB on AEM were more likely to have RBBB or interventricular conduction delay after TAVR (Figure).
Conclusions: Delayed H-AVB occurred in 15% of our patients discharged after TAVR and was identified as late as 24 days post-discharge. Ambulatory monitoring of post-TAVR patient is warranted, especially among patients with baseline RBBB, but even among patients without significant conduction disease. Further study to identify risk factors is needed.