General Session V - Venous Thromboembolism and IVC Filters
General Session V - Venous Thromboembolism and IVC Filters
Shorter Time to Mechanical Thrombectomy Is Associated with Improved Outcomes in Patients with Acute Pulmonary Embolism: Results from the FLASH Registry
Tuesday, March 5, 2024
8:42 AM – 8:52 AM EST
Location: Tampa Bay Ballroom Salons 1-4
Objective: Acute pulmonary embolism (PE) can present emergently with adverse outcomes if reperfusion is not rapidly achieved. However, less-emergent cases may not receive immediate intervention. While mechanical thrombectomy (MT) is increasingly used to effectively treat both high- and intermediate-risk PE, the optimal time to treatment has not been established. The impact of time from hospital admission to mechanical thrombectomy (TtMT) on patient outcomes was evaluated using data from the US cohort of the FLASH registry.
Methods: The FlowTriever All-comer Registry for Patient Safety and Hemodynamics (FLASH, NCT03761173) is a prospective, multicenter registry of acute PE patients treated with a large bore aspiration MT system. Patients were followed for 6 months post-thrombectomy. Data from the 800-patient US cohort were used to assess the impact of TtMT (short: ≤12 hours; long: >12 hours) on several outcomes. P-values were calculated using Wilcoxon rank sum tests. Generalized linear mixed modeling (GLMM) was used to evaluate impacts of TtMT on longitudinal changes in echocardiographic right ventricle/left ventricle (RV/LV) ratio post-thrombectomy after controlling for potential confounders.
Results: The median TtMT was 19.2 hours [interquartile range (IQR): 9.6, 28.8; n=787]. TtMT medians were 6.01 hours [IQR 4.02, 7.97; n=242] for those with short TtMT and 24.73 hours [IQR 18.75, 39.38; n=545] for the long TtMT group. Patients with short TtMT had significantly greater intraprocedural reduction of mean and systolic pulmonary artery pressures (PAPs), greater reduction of RV/LV ratio at all follow-up visits, and longer 6-minute walk test (6MWT) distance at the 6-month visit (Table 1). The PE-specific quality of life assessment (PEmb-QoL) suggested a trend toward better QoL scores with short TtMT. Patients with long TtMT are predicted to have 0.084 (P=0.023), 0.090 (P=0.013), and 0.094 (P=0.028) less reduction in RV/LV ratio at their 48-hour, 30-day, and 6-month visits, respectively (Figure 1A), and predicted RV/LV ratio reduction using observed data is greater for short TtMT at all follow-up visits (Figure 1B).
Conclusions: Shorter time from admission to mechanical thrombectomy for PE was associated with greater PAP reduction, greater RV/LV ratio reduction at all follow-ups, and longer 6-month 6MWT distance. These data suggest that rapid initiation of mechanical thrombectomy following hospital admission may yield better acute and longer-term outcomes in PE patients. Further analyses are needed to explore optimal TtMT and its impact on additional clinical outcomes.
