Association of Hospital Volume With Outcomes of Pulmonary Embolism in the United States

BACKGROUND: Pulmonary embolism (PE) remains a leading cause of mortality in the United States. While prior studies show improved outcomes at higher-volume centers, the understanding of procedural utilization remains limited. AIMS: Therefore, this study aimed to evaluate the association of hospital PE volume and intervention utilization with clinical and financial outcomes in adult patients. METHODS: All non-elective adults (≥18 years) admitted for PE were identified using the 2016-2022 National Inpatient Sample. Annual PE admissions and intervention (mechanical thrombectomy, catheter-directed thrombolysis) caseloads were calculated for each facility. Centers were stratified by PE volume tertiles and classified as low- (LVH), medium- (MVH), and high-volume hospitals (HVH). Outcomes included in-hospital mortality, complications, length of stay, and inpatient costs. Multivariable regression and mixed-effect models were used to evaluate associations between hospital PE volume, intervention utilization, and outcomes. RESULTS: Of an estimated 1,475,860 PE hospitalizations, 12.4% and 57.2% were treated at LVH and HVH, respectively. Compared with HVH, LVH had higher unadjusted in-hospital mortality (10.7 vs. 6.0%, p < 0.001) and higher rates of cardiac and respiratory complications, while undergoing fewer interventions (5.2 vs. 7.2%, p < 0.001). Following risk adjustment, LVH remained associated with increased odds of in-hospital mortality (AOR 2.08, 95% CI 1.99-2.17), cardiac (AOR 1.16, 95% CI 1.09-1.24), and respiratory complications (AOR 1.11, 95% CI 1.07-1.14), and lower odds of receiving intervention (AOR 0.68, 95% CI 0.64-0.73). Higher institutional PE volume and intervention utilization were each independently associated with reduced mortality (p < 0.001). Notably, increasing PE volume mitigated differences in mortality associated with intervention utilization. CONCLUSION: Lower hospital PE volume was associated with higher mortality and complications. Additionally, intervention utilization was positively correlated with institutional PE caseload. Of note, higher PE admission volume was associated with improved outcomes regardless of treatment strategy. These findings suggest institutional experience may play a key role in high-quality PE care.