Abstract
Background
High-risk pulmonary embolism (PE) is associated with substantial mortality, and contemporary guidelines recommend prompt reperfusion therapy when feasible. However, real-world data describing how reperfusion is used in practice, and its outcomes, remain limited.
Methods and Results
We conducted an observational analysis of patients with high-risk PE enrolled in the Tokyo Cardiovascular Care Unit Network registry between 2020 and 2022. High-risk PE was defined as a presentation complicated with shock, sustained hypotension, or cardiac arrest. Reperfusion therapies included systemic thrombolysis, catheter-based therapy, and surgical embolectomy. Of 1,217 patients with PE, 185 (15.2%) met the high-risk PE criteria. Reperfusion therapy was administered to 43.8% of patients (systemic thrombolysis, 27.6%; surgical embolectomy, 13.0%; catheter-based therapy, 3.2%), and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) was used in 29.7% of patients. Overall, in-hospital mortality was 14.6%. Mortality was lower with than without reperfusion therapy (8.6% vs. 19.2%), without significant differences in bleeding events. In multivariable logistic regression analysis, cardiac arrest, VA-ECMO use, and lack of reperfusion therapy were independently associated with increased in-hospital mortality risk.
Conclusions
In this contemporary multicenter registry, reperfusion therapy was used in fewer than half of patients with high-risk PE and was associated with lower in-hospital mortality, although residual confounding cannot be excluded given the observational study design. These findings highlight both the potential benefit and the incomplete real-world adoption of guideline-recommended reperfusion strategies.
Key Words: Emergency cardiovascular care, Extracorporeal membrane oxygenation, High-risk pulmonary embolism, In-hospital mortality, Reperfusion therapy
Central Figure.
High-risk pulmonary embolism (PE) is a life-threatening condition associated with substantial morbidity and mortality.1 A recent study from the US Pulmonary Embolism Response Team (PERT) registry reported in-hospital mortality rates of 42.1% and 17.2% among patients with and without circulatory collapse, respectively.2 Systemic thrombolysis is recommended as first-line reperfusion therapy; when contraindicated or unsuccessful, surgical embolectomy or catheter-based therapy are recommended alternatives.3 Despite these recommendations, reperfusion therapy remains underused in routine clinical practice.4,5 The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has increased in recent years,6 prompting questions regarding its optimal integration with reperfusion strategies.6–9
Several administrative database studies have examined high-risk PE,6,10,11 yet contemporary analyses capturing the full clinical spectrum, including treatment selection, timing, and outcomes in dedicated emergency cardiovascular services, remain limited.2,12 The Tokyo Cardiovascular Care Unit (CCU) Network is a regional cardiovascular emergency transport system that coordinates ambulance triage and rapid transfer to acute cardiovascular care facilities in collaboration with the Tokyo Fire Department.13–15 High-risk PE constitutes one of the emergency conditions prioritized within this system.13,16,17
The present study explored current management practices, clinical outcomes, and the impact of reperfusion therapy on in-hospital mortality among patients with high-risk PE using Tokyo CCU Network data.
Methods
The Tokyo CCU Network database is an ongoing multicenter registry that prospectively collects information on emergency admissions to acute cardiovascular facilities, based on data provided by emergency medical services and investigators at participating hospitals.13,15–18 The Tokyo CCU Network is registered with the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000013128). As of December 2022, the Tokyo CCU Network included 76 hospitals serving approximately 14 million residents.
The data used in the present study were anonymized before analysis, and the requirement for informed consent was waived in accordance with national ethical guidelines. The study protocol was approved by the Institutional Review Board of the Tokyo CCU Network Scientific Committee (Approval no. 16-002).
The present analysis included data collected between 2020 and 2022. Among 1,217 patients diagnosed with PE during this period, 185 with high-risk PE who had complete data on reperfusion therapy and in-hospital outcomes were included in the study (Figure). The diagnosis of PE required confirmation by contrast-enhanced computed tomography, a high-probability ventilation–perfusion scan, or pulmonary angiography.19 At presentation, high-risk PE was defined by shock, sustained hypotension, or cardiac arrest. In-hospital onset included onset in healthcare facilities. Venous thromboembolism (VTE) risk factors were categorized according to the European Society of Cardiology guidelines.3 Treatment decisions followed Japanese Circulation Society or European Society of Cardiology guidelines3,20 and were made at the discretion of the treating clinician. Reperfusion strategies included systemic thrombolysis, catheter-based therapy, and surgical embolectomy. When multiple modalities were used, patients were categorized according to the final therapy to reflect treatment escalation.7 In-hospital outcomes comprised all-cause mortality and bleeding events, defined as intracranial hemorrhage, gastrointestinal bleeding, procedure site bleeding, or bleeding requiring transfusion.
Figure.
Flowchart of patient selection. PE, pulmonary embolism; VA-ECMO, veno-arterial extracorporeal membrane oxygenation.
Dichotomous variables were compared using the Chi-squared or Fisher’s exact test, as appropriate. An exploratory multivariable logistic regression model assessed independent predictors of in-hospital mortality, incorporating variables that were significant in univariable analyses and focusing on those representing early disease severity and initial treatment decisions.3,20 Variables included in the model were age, sex, cardiac arrest, VA-ECMO use, and reperfusion therapy, all of which had no missing data. Two-tailed P<0.05 was considered statistically significant.
Results
Patient Characteristics and Overall Outcomes
The baseline characteristics, management strategies, and in-hospital outcomes for the 185 patients included in this study are presented in Table 1. The median age of the study cohort was 65 years (interquartile range 52–78 years), and 42.7% of patients were men. Across the entire cohort, 8.7% had active cancer, 20.7% had major transient VTE risk factors, 27.7% had minor transient risk factors, 6.0% had permanent risk factors, and 40.8% had unprovoked PE. In-hospital or healthcare-facility onset of PE was observed in 26.5% of patients. Cardiac arrest occurred in 17.8% of patients and 74.3% had residual deep vein thrombosis.
Table 1.
Patient Characteristics and In-Hospital Outcomes Overall and According to Reperfusion Therapy
| Overall | Any reperfusion | No reperfusion | P value | |
|---|---|---|---|---|
| No. patients | 185 | 81 | 104 | |
| Baseline characteristics | ||||
| Age (years) | 65 [52–78] | 61 [52–76] | 68 [53–80] | 0.069 |
| Male sex | 79/185 (42.7) | 42/81 (51.9) | 37/104 (35.6) | 0.026 |
| BMI ≥25 kg/m2 | 73/175 (41.7) | 39/78 (50.0) | 34/97 (35.1) | 0.046 |
| Comorbidities | ||||
| Hypertension | 74/183 (40.4) | 33/81 (40.7) | 41/102 (40.0) | 1 |
| Diabetes | 35/183 (19.1) | 16/81 (19.8) | 19/102 (18.6) | 0.852 |
| Dyslipidemia | 37/183 (20.2) | 10/81 (12.3) | 27/102 (26.5) | 0.025 |
| Hyperuricemia | 13/182 (7.1) | 6/80 (7.5) | 7/102 (6.9) | 1 |
| Smoking (including past) | 41/169 (24.3) | 19/71 (26.8) | 22/98 (22.4) | 0.586 |
| Dialysis | 0/185 (0) | 0/81 (0) | 0/104 (0) | 1 |
| Atrial fibrillation | 7/183 (8.4) | 3/81 (3.7) | 4/102 (3.9) | 1 |
| Peripheral arterial disease | 1/181 (1.2) | 0/80 (0) | 1/101 (1.0) | 1 |
| History of HF hospitalization | 6/183 (7.2) | 0/81 (0) | 6/102 (5.9) | 0.035 |
| History of MI | 0/182 (0) | 0/81 (0) | 0/101 (0.0) | 1 |
| History of stroke | 9/183 (10.8) | 4/81 (0) | 5/102 (4.9) | 1 |
| Active cancer | 16/184 (8.7) | 6/81 (7.4) | 10/103 (9.7) | 0.612 |
| VTE risk factors | ||||
| Major transient | 38/184 (20.7) | 12/81 (14.8) | 26/103 (25.2) | 0.10 |
| Minor transient | 51/184 (27.7) | 18/81 (22.2) | 33/103 (32.0) | 0.184 |
| Permanent | 11/184 (6.0) | 4/81 (4.9) | 7/103 (6.8) | 0.758 |
| Unprovoked VTE | 75/184 (40.8) | 45/81 (55.6) | 30/103 (29.1) | <0.001 |
| Presentation | ||||
| In-hospital onset | 49/185 (26.5) | 14/81 (17.3) | 35/104 (33.7) | 0.012 |
| Cardiac arrest | 33/185 (17.8) | 10/81 (12.3) | 23/104 (22.1) | 0.085 |
| Concomitant DVT | 130/175 (74.3) | 59/78 (75.6) | 71/97 (73.2) | 0.732 |
| Treatment in the acute phase | ||||
| Heparin bolus | 128/183 (69.9) | 50/81 (61.7) | 78/102 (76.5) | 0.036 |
| Initial parental anticoagulation | 167/170 (98.2) | 68/68 (100) | 99/102 (97.1) | 0.276 |
| Systemic thrombolysis | 51/185 (27.6) | 51/81 (62.9) | ||
| Catheter-based therapy | 6/185 (3.2) | 6/81 (7.4) | ||
| Surgical embolectomy | 24/185 (13.0) | 24/81 (29.6) | ||
| Systemic urokinase infusion | 6/185 (3.2) | 6/81 (7.4) | ||
| VA-ECMO use | 55/185 (29.7) | 29/81 (35.8) | 26/104 (25.0) | 0.111 |
| Ventilator support | 86/185 (46.5) | 42/81 (51.9) | 44/104 (42.3) | 0.197 |
| CRRT | 8/185 (9.4) | 4/81 (4.9) | 4/104 (3.8) | 0.717 |
| TTM | 25/185 (13.5) | 11/81 (13.6) | 14/104 (13.5) | 0.981 |
| Inferior vena cava filter | 12/183 (6.6) | 9/81 (11.1) | 3/102 (2.9) | 0.035 |
| Oral anticoagulation | 154/158 (97.5) | 72/73 (98.6) | 82/85 (96.5) | 0.625 |
| Direct oral anticoagulant | 143/147 (97.3) | 68/69 (98.6) | 75/78 (96.2) | 0.623 |
| Warfarin | 23/153 (15.0) | 11/73 (13.6) | 12/80 (12.4) | 1 |
| In-hospital outcomes | ||||
| All-cause death | 27/185 (14.6) | 7/81 (8.6) | 20/104 (19.2) | 0.043 |
| Deterioration or recurrence | 12/183 (6.6) | 3/81 (3.7) | 9/102 (8.8) | 0.232 |
| Bleeding event | 22/185 (11.9) | 10/81 (12.3) | 12/104 (11.5) | 0.866 |
| Intracranial hemorrhage | 4/185 (2.2) | 3/81 (3.7) | 1/104 (1.0) | 0.203 |
| Gastrointestinal bleeding | 4/185 (2.2) | 1/81 (1.2) | 3/104 (2.9) | 0.444 |
| Procedure site bleeding | 8/185 (4.3) | 4/81 (4.9) | 4/104 (3.8) | 0.717 |
Unless indicated otherwise, values are presented as the median [interquartile range] or n/N (%). BMI, body mass index; CRRT, continuous renal replacement therapy; DVT, deep vein thrombosis; HF, heart failure; MI, myocardial infarction; TTM, target temperature management; VA-ECMO, veno-arterial extracorporeal membrane oxygenation; VTE, venous thromboembolism.
Reperfusion therapy was administered to 81 (43.8%) patients: systemic thrombolysis in 27.6%, surgical embolectomy in 13.0%, and catheter-based therapy in 3.2%. VA-ECMO and inferior vena cava filters were used in 29.7% and 6.6% of patients, respectively. The in-hospital mortality rate was 14.6% and bleeding events occurred in 11.9% of patients.
Reperfusion Therapy vs. No Reperfusion
Of the patients undergoing reperfusion therapy, 62.9% received systemic thrombolysis, 29.6% underwent surgical embolectomy, and 7.4% received catheter-based therapy. Patients who received reperfusion therapy were more often men and obese, and more likely to have unprovoked PE, whereas in-hospital PE onset was less frequent in this group. The use of a heparin bolus use was lower, whereas inferior vena cava filter placement was more common, in patients undergoing reperfusion therapy than in those without reperfusion. All-cause mortality was significantly lower among patients receiving reperfusion therapy than not (8.6% vs. 19.2%; P=0.043). Rates of bleeding event did not differ significantly between those with and without reperfusion therapy (Table 1).
VA-ECMO vs. No VA-ECMO
Patients requiring VA-ECMO were younger (median age 58 vs. 70.5 years; P=0.002), more often men, and more likely to have major transient VTE risk factors or unprovoked PE than those without VA-ECMO. Cardiac arrest was significantly more common among patients requiring VA-ECMO. Reperfusion therapy was used at comparable rates in patients with and without VA-ECMO (52.7% vs. 40.0%, respectively). All-cause mortality (29.1% vs. 8.5%) and bleeding events (27.3% vs. 5.4%) were significantly higher among patients requiring VA-ECMO (all P<0.001). Procedure site bleeding was also more frequent among patients requiring VA-ECMO (Supplementary Table 1).
Cardiac Arrest vs. No Cardiac Arrest
The use of any reperfusion therapy tended to be lower among patients with than without cardiac arrest (30.3% vs. 46.7%; P=0.085). Thrombolysis was used less frequently (9.1% vs. 31.6%; P=0.009) and catheter-based therapy was more common (12.1% vs. 1.3%; P=0.010) among patients with than without cardiac arrest. Surgical embolectomy rates were similar between the 2 groups. All-cause mortality (39.4% vs. 9.2%) was markedly higher in the group with than without cardiac arrest (P<0.001). Bleeding events were higher in the group with cardiac arrest, albeit not significantly (P=0.068), and procedure site bleeding was more common (Supplementary Table 2).
Outcomes According to Survival
Patients who died in hospital were more often men and had significantly higher rates of cardiac arrest. Reperfusion therapy, in particular systemic thrombolysis, was used less frequently (7.4% vs. 31.0%, P=0.010), whereas the use of VA-ECMO was significantly higher (59.3% vs. 24.7%, P<0.001), in the group of patients who died relative to those who survived to discharge. Patients who died in hospital more frequently experienced clinical deterioration or recurrent PE (19.2% vs. 4.5%; P=0.016) and had higher rates of bleeding events (29.6% vs. 8.9%; P=0.002) than those who survived to discharge (Table 2). In multivariable analysis, cardiac arrest (odds ratio [OR] 3.73; 95% confidence interval [CI] 1.33–10.46; P=0.012), VA-ECMO use (OR 3.08; 95% CI 1.01–8.93; P=0.038), and reperfusion therapy (OR 0.34; 95% CI 0.12–0.95; P=0.039) were independently associated with in-hospital mortality (Table 3).
Table 2.
Patient Characteristics According to In-Hospital Death or Survival to Discharge
| Survival to discharge | In-hospital death | P value | |
|---|---|---|---|
| No. patients | 158 | 27 | |
| Baseline characteristics | |||
| Age (years) | 65 [53–78] | 65 [49.5–74] | 0.609 |
| Male sex | 63/158 (39.9) | 16/27 (59.3) | 0.06 |
| BMI ≥25 kg/m2 | 59/151 (39.1) | 14/24 (58.3) | 0.117 |
| Comorbidities | |||
| Hypertension | 64/158 (40.5) | 10/25 (40.0) | 1 |
| Diabetes | 29/158 (18.4) | 6/25 (24.0) | 0.584 |
| Dyslipidemia | 33/158 (20.9) | 4/25 (16.0) | 0.789 |
| Hyperuricemia | 11/157 (7.0) | 2/25 (8.0) | 1 |
| Smoking (including past) | 36/147 (24.5) | 5/22 (22.7) | 1 |
| Dialysis | 0/158 (0.0) | 0/25 (0) | 1 |
| Atrial fibrillation | 5/158 (3.2) | 2/25 (8.0) | 0.245 |
| Peripheral arterial disease | 1/154 (0.6) | 0/25 (0) | 1 |
| History of HF hospitalization | 4/158 (2.5) | 2/25 (8.0) | 0.190 |
| History of MI | 0/158 (0.6) | 0/25 (7.4) | 1 |
| History of stroke | 8/158 (5.1) | 1/25 (4.0) | 1 |
| Active cancer | 15/157 (9.6) | 1/27 (3.7) | 0.474 |
| VTE risk factors | |||
| Major transient | 35/157 (22.3) | 3/27 (11.1) | 0.301 |
| Minor transient | 43/157 (27.4) | 8/27 (29.6) | 0.818 |
| Permanent | 9/157 (5.7) | 2/27 (7.4) | 0.666 |
| Unprovoked VTE | 62/157 (39.5) | 13/27 (48.1) | 0.525 |
| Presentation | |||
| In-hospital onset | 42/158 (26.6) | 7/27 (25.9) | 0.943 |
| Cardiac arrest | 20/158 (12.7) | 13/27 (48.1) | <0.001 |
| Concomitant DVT | 114/153 (74.5) | 16/22 (72.7) | 1 |
| Treatment in the acute phase | |||
| Heparin bolus | 109/156 (69.9) | 19/27 (70.4) | 1 |
| Initial parental anticoagulation | 144/145 (99.3) | 23/25 (92.0) | 0.057 |
| Any reperfusion | 74/158 (46.8) | 7/27 (25.9) | 0.043 |
| Systemic thrombolysis | 49/158 (31.0) | 2/27 (7.4) | 0.010 |
| Catheter-based therapy | 5/158 (3.2) | 1/27 (3.7) | 1 |
| Surgical embolectomy | 20/158 (12.7) | 4/27 (14.8) | 0.758 |
| Systemic urokinase infusion | 5/158 (3.2) | 1/27 (3.7) | 1 |
| VA-ECMO use | 39/158 (24.7) | 16/27 (59.3) | <0.001 |
| Ventilator support | 63/158 (39.9) | 23/27 (85.2) | <0.001 |
| CRRT | 6/158 (3.8) | 2/27 (7.4) | 0.330 |
| TTM | 15/158 (9.5) | 10/27 (37.0) | <0.001 |
| Inferior vena cava filter | 11/157 (7.0) | 1/26 (3.8) | 1 |
| Oral anticoagulation | 151/151 (100) | 3/7 (42.9) | <0.001 |
| Direct oral anticoagulant | 141/141 (100) | 2/6 (33.3) | <0.001 |
| Warfarin | 22/146 (15.1) | 1/7 (14.3) | 1 |
| In-hospital outcomes | |||
| Deterioration or recurrence | 7/157 (4.5) | 5/26 (19.2) | 0.016 |
| Bleeding event | 14/158 (8.9) | 8/27 (29.6) | 0.002 |
| Intracranial hemorrhage | 3/158 (1.9) | 1/27 (3.7) | 0.471 |
Unless indicated otherwise, values are presented as the median [interquartile range] or n/N (%). Other abbreviations as in Table 1.
Table 3.
Multivariable Logistic Regression Analysis Identifying Independent Risk Factors for In-Hospital Mortality
| Variable | Coefficient | OR (95% CI) | P value |
|---|---|---|---|
| Age | 0.010 | 1.010 (0.977–1.043) | 0.568 |
| Male sex | 0.827 | 2.286 (0.884–5.916) | 0.088 |
| Cardiac arrest | 1.315 | 3.725 (1.327–10.456) | 0.012 |
| VA-ECMO use | 1.124 | 3.078 (1.062–8.925) | 0.038 |
| Any reperfusion | −1.071 | 0.343 (0.124–0.947) | 0.039 |
CI, confidence interval; OR, odds ratio; VA-ECMO, veno-arterial extracorporeal membrane oxygenation.
Discussion
This study characterized the current use and outcomes of reperfusion therapy across the full spectrum of patients with high-risk PE in Japan using data from the Tokyo CCU Network. Comprehensive real-world evidence encompassing all presentations of high-risk PE remains limited. A recent study analyzed 991 patients with high-risk PE but included only those who received reperfusion therapy or extracorporeal membrane oxygenation (ECMO).12 Similarly, the US PERT registry enrolled 1,442 high-risk patients but was restricted to centers with established PERT programs.2
In the present cohort, reperfusion therapy was performed in 43.8% of patients and was associated with lower in-hospital mortality without an increase in bleeding events. In multivariable analysis, cardiac arrest, VA-ECMO use, and the absence of reperfusion therapy were independently associated with mortality, suggesting a possible association between active reperfusion therapy and lower in-hospital mortality in this population. Because of the small sample size and limited number of events, additional analyses to further clarify the impact of cardiac arrest and ECMO use were not feasible; therefore, the findings of this study should be interpreted with caution.
Compared with the PERT registry,2 the overall reperfusion rate in the present study was similar, although catheter-based therapy was used far less frequently, likely reflecting the limited availability of dedicated PE devices in Japan. A recent systematic review (27 studies, 1,517 patients; 2010–2020) reported pooled in-hospital mortality, major bleeding, and intracranial hemorrhage rates of 28.3%, 13.8%, and 3.6%, respectively,21 broadly consistent with our findings.
Earlier reports indicated reperfusion therapy was used in approximately 30% of hemodynamically unstable PE patients,4,5 whereas the rates from both the present study and the PERT registry2 are near 40%. This difference may reflect higher intervention rates in specialized care settings; nevertheless, the overall utilization of reperfusion therapy likely remains suboptimal. Barriers to thrombolysis include perceived bleeding risk, frequent relative contraindications, and heterogeneity in clinical presentation. Catheter-based therapy has gained attention with the introduction of large-bore aspiration devices, but supporting evidence largely derives from intermediate-high-risk PE,22,23 and reliance on specialized centers limits generalizability; it should be noted that these devices are unavailable in Japan. Surgical embolectomy enables definitive clot removal but remains constrained by procedural invasiveness and the need for immediate access to experienced cardiovascular surgeons.
The use of VA-ECMO was relatively high in our cohort, consistent with Japanese practice patterns.6,24 Although ECMO serves as supportive rather than definitive therapy, it can rapidly unload the right ventricle and stabilize hemodynamics. In the present study, VA-ECMO was used in 29.7% of patients; those receiving ECMO more frequently presented with cardiac arrest, more often underwent surgical embolectomy, and experienced higher mortality and bleeding rates. In the US, ECMO use was 6.3% in the PERT registry2 and 2.3% in a recent nationwide inpatient sample analysis.7 The latter suggested that ECMO combined with reperfusion therapy may improve survival after cardiac arrest.7
Regarding reperfusion strategies during ECMO, a systematic review of 17 studies (327 VA-ECMO-treated PE patients; 2010–2020) reported mortality rates of 22.6% with mechanical reperfusion, primarily surgical embolectomy, and 42.8% with other strategies, yielding an absolute difference of 20.2% (95% CI 5.2–27.6%).8 Similarly, a Japanese registry of 2,035 patients with symptomatic PE reported the lowest 30-day mortality after surgical embolectomy (6.3%), compared with thrombolysis (25%), anticoagulation alone (39.3%), and catheter-based therapy (43.8%).9 Owing to limitations in the predefined data elements of this registry, we could not ascertain the temporal sequence of cardiac arrest, ECMO initiation, and reperfusion therapy, and thus were unable to formally assess this potential source of confounding. Given the relatively high rate of ECMO use in Japan, further research should define the optimal timing and combinations of ECMO and reperfusion therapy in the management of high-risk PE patients.
Study Limitations
This study has several limitations. First, although the Tokyo CCU Network captures real-world, all-comer practice across multiple centers, the absolute number of high-risk PE patients was modest, and the data were derived from the period between 2020 and 2022. Therefore, the findings are limited to this specific network and may have limited generalizability to other regions or healthcare systems. Second, baseline cardiac function or hemodynamic parameters, detailed bleeding risk profiles and data on right heart thrombi, which may influence severity and management, were not available. Moreover, the definition of a bleeding event used in this study does not follow commonly accepted criteria, such as the International Society on Thrombosis and Haemostasis definition,25–27 and therefore lacks objectivity. Third, detailed information regarding reperfusion therapy procedures, including the doses of thrombolytic agents and catheter-based techniques, was not available. In addition, the timing of ECMO initiation relative to reperfusion therapy and cardiac arrest could not be determined. Treatment selection or withholding, particularly in the setting of cardiac arrest, likely reflected clinician judgment and institutional resources, introducing potential confounding. Finally, the exploratory multivariable analysis included a limited number of covariates and may be subject to residual confounding due to the exclusion of several established prognostic markers, such as baseline right ventricular function, hemodynamic parameters, lactate levels, comorbidity burden, and embolic burden. This prognostic analysis focused on all-cause mortality;28 further clarification of the causes of death may help better delineate the impact of reperfusion therapy.
Conclusions
This study described the real-world use and outcomes of reperfusion therapy among patients with high-risk PE within a large regional emergency network. Reperfusion therapy was used in fewer than half the patients with high-risk PE and was associated with lower in-hospital mortality, without an apparent increase in bleeding events, although residual confounding cannot be excluded given the observational study design. These findings highlight both the potential benefit of reperfusion therapy and the incomplete adoption of guideline-recommended reperfusion strategies in real-world practice.
Disclosures
S.K. has received research grants from Pfizer and lecture fees from Novartis and Bristol Myers Squibb, outside the submitted work. S.K. is also an Associate Editor of Circulation Reports. The other authors report no conflicts of interest.
IRB Information
All data were anonymized before analysis, and the requirement for informed consent was waived in accordance with national ethical guidelines. The study protocol was approved by the Institutional Review Board of the Tokyo CCU Network Scientific Committee (Approval no. 16-002).
Supplementary Files
Supplementary Table 1. Supplementary Table 2.
Acknowledgments
The authors thank the members of the Tokyo CCU Network and Kozue Murayama (Tokyo CCU Network Secretariat) for their assistance with data collection.
Funding Statement
Sources of Funding: The Tokyo CCU Network data registry is financially supported by the Tokyo Metropolitan Government, Japan. The funders had no role in study design or data interpretation. This study was supported, in part, by a JSPS KAKENHI Grant-in-Aid for Scientific Research (C) (Grant no. 24K12164).
Data Availability
The anonymized data supporting the findings of this study are available from the corresponding author upon reasonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Supplementary Table 1. Supplementary Table 2.
Data Availability Statement
The anonymized data supporting the findings of this study are available from the corresponding author upon reasonable request.