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.