Pericardial Effusion During LAAO Associated With Higher Risk of Mortality

Close up of hand smile female doctor examining senior woman patient lying down on the bed in hospital with stethoscope listening to senior patients breathing.
A study was conducted to examine the incidence, associated characteristics, and outcomes of pericardial effusion following LAAO.

In-hospital pericardial effusion (PE) during transcatheter left atrial appendage occlusion (LAAO) is rare but is associated with a substantially increased risk for stroke and in-hospital and early postdischarge mortality, according to a study in Circulation: Cardiovascular Interventions.

Researchers used data from the National Cardiovascular Data Registry (NCDR) LAAO Registry. Eligible participants had attempted or successful first-generation Watchman device implantation from January 1, 2016, to December 31, 2019. Patients who had procedures after December 31, 2019, were excluded to minimize possible follow-up bias owing to the COVID-19 pandemic.

The primary outcome was site-reported PE that required intervention of either percutaneous drainage, cardiac surgery, or both. A total of 65,355 patients (mean age, 76.2±8.1 years; 41.3% were women; 37.6% had diabetes) were included.

Among the cohort, 1.35% had in-hospital PE requiring intervention. Percutaneous drainage was conducted in 771 cases (1.18%) and cardiac surgery in 177 (0.27%). Older age, being a woman, having normal left ventricular function, paroxysmal atrial fibrillation, lower serum albumin, previous clinically relevant bleeding, and preprocedural dual antiplatelet therapy were independently associated with in-hospital PE requiring intervention. Sinus rhythm during the procedure, no delivery sheath used, more than 1 delivery sheath used, and moderate sedation compared with general anesthesia were also independently associated with PE requiring intervention.

Patients with a PE requiring intervention had a significantly increased risk for any stroke (odds ratio [OR] 6.58 [95% CI, 3.32-13.05], P <.0001), all-cause mortality (OR 56.88 [95% CI, 39.79-81.32], P <.0001), and the composite of death, stroke, or systemic embolism (OR 28.64 [95% CI, 21.24-38.61], P <.001) compared with patients who did not have PE.

Follow-up data at 45 days were available for 55,996 patients. The rate of postdischarge PE requiring intervention was 1.82% in those with in-hospital PE vs 0.11% in those without in-hospital PE (OR 18.38 [95% CI, 9.80-34.45], P <.001). Patients with in-hospital PE had a significantly increased risk of early postdischarge mortality (OR 3.52 [95% CI, 2.23-5.54], P <.0001) and the composite of death, stroke, or systemic embolism (OR 3.42 [95% CI, 2.31-5.07], P <.0001).

Among several study limitations, adverse event rates were based on site-reported data and underreporting is possible. Also, unadjusted ORs for clinical outcomes are reported and may be subject to confounding. Furthermore, the investigators did not directly assess whether guidance with intracardiac echocardiography was independently associated with pericardial effusion, and they only included patients with the older-generation Watchman device.

“Strategies to minimize PE, potentially guided by an understanding of the associated patient and procedural risk factors, will be critical to improve the risk-benefit ratio for this therapy,” stated the researchers.

Disclosure: Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Price MJ, Valderrábano M, Zimmerman S, et al. Periprocedural pericardial effusion complicating transcatheter left atrial appendage occlusion: a report from the NCDR LAAO registry. Circ Cardiovasc Interv. Published online April 2, 2022. doi: 10.1161/CIRCINTERVENTIONS.121.011718