Pericardial effusion requiring intervention in patients undergoing percutaneous left atrial appendage occlusion: Prevalence, predictors, and associated in-hospital adverse events from 17,700 procedures in the United States

BACKGROUND Left atrial appendage occlusion has shown promise in mitigating the risk of stroke in selected patients with atrial fibrillation. OBJECTIVE The purpose of this study was to determine the real-world prevalence and in-hospital outcomes in left atrial appendage occlusion (Watchman) recipients complicated by pericardial effusion requiring percutaneous drainage or open cardiac surgery-based intervention. METHODS Data were derived from the National Inpatient Sample database from January 2015 to December 2017. The primary outcomes assessed were the prevalence of pericardial effusion requiring intervention and in-hospital outcomes including mortality, other major complications, hospital stay > 1 day, and hospitalization costs. Predictors of pericardial effusion requiring intervention were also analyzed. RESULTS Pericardial effusion requiring intervention occurred in 220 total patients (1.24%). After multivariable adjustment, pericardial effusion requiring intervention was associated with in-hospital mortality (adjusted odds ratio [aOR] 511.6; 95% confidence interval [CI] 122-2145.3), other Watchman-related major complications (aOR 1.35; 95% CI 0.83-2.19), length of stay > 1 day (aOR 17.64; 95% CI 12.56-24.77), and hospitalization cost above the median of $24,327 (aOR 3.58; 95% CI 2.61-4.91). Independent patient predictors of pericardial effusion requiring intervention from the procedure included advanced age (aOR 1.029 per 1-year increase; 95% CI 1.009-1.05 per 1-year increase), higher CHA(2)DS(2)-VASc score (aOR 1.221 per 1-point increase; 95% CI 1.083-1.377 per 1-point increase), and obesity (aOR 2.033; 95% CI 1.464-2.823). CONCLUSION In a large, contemporary real-world cohort of Watchman recipients in US practice, the prevalence of pericardial effusion requiring intervention was 1.24%. Pericardial effusion requiring intervention was associated with several adverse events including increased in-hospital mortality, other major complications, prolonged hospital stay, and hospitalization costs.