Late pericardial effusion (LPE) following left atrial appendage occlusion (LAAO) device implantation was associated with negative patient outcomes, including mortality, suggesting the need for long-term surveillance of these patients, according to an analysis of the Manufacturer and User Facility Device Experience (MAUDE) Registry published May 19 in JACC: Advances.

Through the MAUDE database, using data through December 2024, study investigators Sneha S. Limaye, MD, et al., identified 290 cases of pericardial effusion (PE) with the Amulet device (66% acute PE [APE]; 34% LPE) and 33 cases with the Watchman device (94% APE; 6% LPE).

Results among the Amulet cases showed that 65% of patients with APE and 55% of those with LPE required an intervention, defined as pericardiocentesis, pericardial window or exploratory sternotomy. Furthermore, 8.4% and 8.0% of patients with APE and LPE died, respectively.

Pulmonary artery (PA) injury was suspected to be the cause of APE in 10 patients with APE and two patients with LPE; five patients died, "underscoring the high mortality rate associated with PA injury-related PEs," the authors write.

Results among the Watchman cases showed that 77% of those with APE and one of the two patients with LPE required an intervention. Two patients with APE and one patient with LPE died. No PA injury was observed.

The authors note the potential to obtain "meaningful large registry information for a low frequency complication between devices" through ACC's NCDR LAAO Registry.

"These findings are novel and in contrast to the existing large prospective randomized controlled trials that have been performed on LAAO devices which report no morbidity and mortality associated with postprocedural PE," write the authors. "Further studies are needed to fully understand the incidence of LPE and that of PEs caused by PA injury following LAAO."