Is there an optimal "door to cath time" in the treatment of acute pulmonary embolism with catheter-directed thrombolysis?

Percutaneous interventions for pulmonary embolism

Pulmonary embolism (PE) ranks as a leading cause of in-hospital mortality and the third most common cause of cardiovascular death. The spectrum of PE manifestations varies widely, making it difficult to determine the best treatment approach for specific patients. Conventional treatment options include anticoagulation, thrombolysis, or surgery, but emerging percutaneous interventional procedures are being investigated for their potential benefits in heterogeneous PE populations. These novel interventional techniques encompass catheter-directed thrombolysis, mechanical thrombectomy, and hybrid approaches combining different mechanisms. Furthermore, inferior vena cava filters are also available as an option for PE prevention. Such interventions may offer faster improvements in right ventricular function, as well as in pulmonary and systemic haemodynamics, in individual patients. Moreover, percutaneous treatment may be a valid alternative to traditional therapies in high bleeding risk patients and could potentially reduce the burden of mortality related to major bleeds, such as that of haemorrhagic strokes. Nevertheless, the safety and efficacy of these techniques compared to conservative therapies have not been conclusively established. This review offers a comprehensive evaluation of the current evidence for percutaneous interventions in PE and provides guidance for selecting appropriate patients and treatments. It serves as a valuable resource for future researchers and clinicians seeking to advance this field. Additionally, we explore future perspectives, proposing "percutaneous primary pulmonary intervention" as a potential paradigm shift in the field.

The timing of death in acute pulmonary embolism patients regarding the mortality risk stratification at admission to the hospital

Background

The management of patients with acute pulmonary embolism (aPE) depends on the severity of aPE. The timing of death in various aPE risk subgroups is only partially known.

Methods

1618 patients with an objectively established aPE diagnosis with computed tomography pulmonary angiography enrolled in the regional PE registry were included in the study. According to ESC criteria, patients were stratified at admission to the hospital in four risk strata. The timing of PE-related and non-PE-related deaths was analyzed regarding mortality risk.

Results

PE-related, and non-PE-related hospital death rates were 1.1 % and 1.5 % in low, 1.1 % and 4.8 % in intermediate-low, 8.1 % and 5.9 % in intermediate-high, and 27.7 % and 6.9 % in high-risk groups, respectively. The median time of PE-related and non-PE-related death across the PE mortality risk were: 4 (1.7-7.5) and 7.0 (4-14.7) days in low, 1.5 (1.0-9.5) and 11.5 (2.0-21.0) days in intermediate-low, 4.0 (2.0-9.0) and 9.0 (5.7-18.2) days in intermediate-high, 2.0 (1.0-4.75) and 7.0 (3.0-21.2) days in high-risk subgroups. 48.2 % and 17.1 % of patients who died in the high and intermediate-high risks died during the first hospital day. After the 6th hospitalization day, PE-related deaths were recorded in 43.9 % of deaths from intermediate-high and 17.9 % from high-risk subgroups.

Conclusion

PE-related mortality is prominent on the first hospitalization day in high and intermediate-high-risk PE. A substantial proportion of intermediate-high and high-risk patient's PE deaths occurred after the first 6 days of hospitalization.

[Ultrasound-accelerated thrombolysis. Initial experience in patients with contraindications to systemic thrombolysis]

Background

acute pulmonary embolism (APE) is a complex and potentially deadly entity, with a variable clinical course, considered the third cardiovascular cause of death. Its management varies according to the stratified risk from anticoagulation to reperfusion therapy, suggesting systemic thrombolysis as a first-choice strategy; however, in a large group of patients their use will be contraindicated, discouraged or will have failed, thus recommending as options in such cases endovascular therapies or surgical embolectomy. With the presentation of 3 clinical cases and a review of the literature, we seek to communicate our initial experience in the use of ultrasound-accelerated thrombolysis with the EKOS system and to investigate key elements for its understanding and application.

Clinical cases

the cases of 3 patients with APE of high and intermediate risk with contraindications for systemic thrombolysis taken to accelerated thrombolysis therapy by ultrasound are discussed. They presented adequate clinical and hemodynamic evolution in the short term, achieving a rapid decrease in thrombolysis, systolic and mean pulmonary arterial pressure, improvement of right ventricular function and reduction of thrombotic burden.

Conclusion

Ultrasound-accelerated thrombolysis is a novel pharmaco-mechanical therapy that combines the emission of ultrasonic waves with the infusion of a local thrombolytic agent, a strategy that, according to different trials and clinical registries, has a high success rate and a good safety profile.

Impact of Time to Intervention on Catheter-Directed Therapy for Pulmonary Embolism

Cather-directed therapies (CDTs) are an evolving therapeutic option for patients with intermediate-risk pulmonary embolism (PE). Although many techniques have been studied, there is limited evidence for the impact of timing of intervention on patient outcomes. Our objective was to assess the association between time to CDT in patients presenting with PE on patient-related outcomes such as length of stay (LOS) and mortality.

DESIGN

Retrospective cohort study.

SETTING

Single academic center.

PATIENTS

We identified patients for which the PE response team had been activated from January 2014 to October 2021. Patients were split into two cohorts depending on whether they went to CDT less than 24 hours from admission (early) versus greater than 24 hours (late).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Data on demographics, timing of interventions, pulmonary hemodynamics, and outcomes were collected. Sixty-four patients were included in analysis. Thirty-nine (63.8%) underwent their procedure less than 24 hours from admission, whereas 25 (36.2%) underwent the procedure after 24 hours. The time from admission to CDT was 15.9 hours (9.1-20.3 hr) in the early group versus 33.4 (27.9-41) in the late group (p ≤ 0.001). There was a greater decrease in pulmonary artery systolic pressure after intervention in the early cohort (14 mm Hg [6-20 mm Hg] vs 6 mm Hg [1-10 mm Hg]; p = 0.022). Patients who received earlier intervention were found to have shorter hospital LOS (4 vs 7 d; p = 0.038) and ICU LOS (3 vs 5 d; p = 0.004). There was no difference in inhospital mortality between the groups (17.9% vs 12%; p = 0.523).

CONCLUSIONS

Patients who underwent CDT within 24 hours of admission were more likely to have shorter hospital and ICU LOS. The magnitude of change in LOS between the two cohorts was not fully explained by the difference in time to CDT. There were modest improvements in pulmonary hemodynamics in the patients who underwent CDT earlier.

Outcomes of Surgical and Mechanical Thrombectomy in Massive Saddle Pulmonary Embolism: A National Perspective

Introduction Saddle pulmonary embolism (PE) is a type of central PE that involves the bifurcation of the pulmonary arteries. First-line treatment is usually systemic thrombolytics, but surgical and mechanical thrombectomy (ST and MT) are used for patients with contraindications to thrombolytics or right heart strain. This study compares surgical and mechanical thrombectomy trends and outcomes in patients with saddle PE. Methods The data was extracted from the National In-Patient Sample (NIS) from 2016-2018 using the International Classification of Diseases-10-Clinical Modification (ICD-10-CM) diagnosis codes. We used the Cochrane-Armitage trend test to analyze the trends of ST and MT and the chi-square test for statistical analyses. A two-tailed p-value of <0.05 was considered statistically significant. Results The overall trend of MT in saddle PE rose from 2016 to 2018, while ST remained stable. Around 95% of patients undergoing ST/MT were emergent admissions, with 82.5% occurring in teaching hospitals. Patients of age >65 years and more with comorbidity burdens were more likely to undergo MT over ST. In-hospital mortality after ST was 15.1%, and after MT was 11.1% (p:<0.001). The most common complications after ST were congestive heart failure (CHF) and atrial fibrillation (AF), and after MT were vascular events and CHF. Conclusion The use of mechanical thrombectomy has steadily increased during the study period. ST is more common in large/teaching hospitals, weekend admissions, and patients transferred from other facilities. MT is more common in elderly patients with a higher comorbidity burden. Patients who underwent MT had lower mortality, length of hospital stay, and post-procedural complications.

Hemodynamic Effects of Ultrasound-Assisted, Catheter-Directed, Very Low-Dose, Short-Time Duration Thrombolysis in Acute Intermediate-High Risk Pulmonary Embolism (from the EKOS-PL Study)

Ultrasound-assisted, catheter-directed, low-dose thrombolysis (USAT) at an average alteplase dose of 20 mg infused over 12 to 24 hours reversed right ventricular disfunction and improved pulmonary hemodynamics in intermediate-high-risk pulmonary embolism patients. As bleeding risk increases with the thrombolytic dose, establishing a minimal effective USAT dosing regimen is of clinical importance. We aimed to investigate hemodynamic effects and safety of a very low-alteplase-dose USAT of 10 mg administered within 5 hours. We included 12 consecutive intermediate-high-risk pulmonary embolism patients with symptoms duration of <14 days and proximal thrombi location in pulmonary arteries. Pulmonary Embolism Response Team decision-based fixed, bilateral ultrasound-assisted alteplase infusions at the rate of 1mg/hour/catheter for 5 hours through EKOS system catheters were made. The primary efficacy measure was the change in invasive systolic and mean pulmonary arteries pressure, and in cardiac index from USAT start to termination. Safety measures were 180-day all-cause death or cardiopulmonary decompensation and bleeding complications. The systolic pulmonary arteries pressure and mean pulmonary arteries pressure decreased from 53 (45.5 to 59) to 37.5 (27.5 to 40.5) mm Hg (p = 0.02) and from 29.5 (27.5 to 32) to 21.5 (15.5 to 25) mm Hg (p = 0.02), respectively. The cardiac index increased from 1.6 (1.5 to 1.8) to 2.2 (1.9 to 2.4) l/min/m², (p = 0.02). No deaths, decompensations, or need for therapy intensification occurred. There was 1 episode of access-site bleeding, which subsided after conservative management. No intracranial hemorrhages appeared. In conclusion, reduced dose and duration USAT improved pulmonary hemodynamics and cardiac function leading to cardiopulmonary stabilization in intermediate-high risk pulmonary embolism patients at a low periprocedural risk.

Evaluating time to treatment and in-hospital outcomes of pulmonary embolism response teams

BACKGROUND

Pulmonary embolism response teams (PERTs) have become increasingly popular at institutions around the country, although the evidence to support their efficacy is limited. PERTs are mechanisms for rapid involvement of a multidisciplinary team in the management of a time-sensitive condition with many treatment options.

METHODS

We retrospectively reviewed 201 patients with PERT activations since inception, collecting data on demographics, time to treatment, treatment modality, and in-hospital outcomes.

RESULTS

Massive pulmonary embolism accounted for 16 (8.7%) PERT activations. The majority of patients were treated without invasive intervention; 91.4% (95% confidence interval [CI], 87.1%-95.7%) of patients received anticoagulation alone, 4.5% (95% CI, 0%-18.6%) had catheter-directed therapy (CDT), and 3.0% (95% CI, 0%-16.9%) had systemic administration of tissue plasminogen activator (tPA). The average time to intervention was 665 minutes (95% CI, 249-1080 minutes) for CDT and 22 minutes (95% CI, 0-456 minutes) for systemic TPA. The average time to anticoagulation was 2.3 minutes (95% CI, 0-43 minutes). There was a trend toward higher rates of cardiac events (odds ratio [OR], 12.68; 95% CI, 0.62-65.74) and death (OR, 3.19; 95% CI, 0.28-5.18) among patients with massive PE. There was a higher rate of cardiac events (OR, 5.66; 95% CI, 1.34-23.83) among patients who received tPA or an invasive intervention. There was no difference in mortality rates of patients who underwent aggressive management compared with anticoagulation alone.

CONCLUSIONS

A dedicated PERT results in efficient delivery of care and excellent outcomes, in part owing to the rapid (on average, 8 minutes) time to initiation of a multidisciplinary discussion. Patients who ultimately underwent CDT had an interval of >10 hours on average between diagnosis and CDT. This provisional or delayed approach to CDT in selected patients who were not improving with anticoagulation alone (and therefore had potential for higher net benefit from a procedure with its own inherent risks) may have resulted in a lower rate of CDT.

Direct versus conventional anticoagulants for treatment of cancer associated thrombosis: a pooled and interaction analysis between observational studies and randomized clinical trials

BACKGROUND

There are emerging observational studies (OSs) to assess real-world comparative effectiveness and safety of direct oral anticoagulants (DOACs) in cancer associated thrombosis (CAT). We conducted a pooled and interaction analysis to compare the treatment effect estimates of DOACs between OSs and randomized controlled trials (RCTs).

METHODS

We systematically searched PUBMED, EMBASE and Cochrane Library for OSs and RCTs that reported recurrent venous thromboembolism (VTE) and/or major bleeding events in CAT patients receiving DOACs and conventional anticoagulants [warfarin or low molecular-weight heparins (LMWHs)]. Relative risks (RRs) for OSs and RCTs were calculated using random-effects models separately, and interaction analyses were afterward applied to assess the comparability between OSs and RCTs.

RESULTS

Baseline characteristic was comparable between identified 10 OSs (35,142 patients) and 8 RCTs (2,602 patients). Overall, no significant difference of treatment effect estimates between OSs and RCTs was detected (Pinteraction: 0.42 for recurrent VTE; Pinteraction: 0.38 for major bleeding). DOACs significantly decreased the risk of recurrent VTE compared with conventional anticoagulants in CAT patients (RR: 0.74, 95% CI: 0.63-0.86, I2: 0% for OSs; RR: 0.65, 95% CI: 0.49-0.86; I2: 0% for RCTs), without increasing major bleeding risk (RR: 0.90, 95% CI: 0.76-1.07, I2: 24.0% for OSs; RR: 1.17, 95% CI: 0.72-1.88, I2: 26.2% for RCTs). Whereas, increased risk of gastrointestinal bleeding (GIB) was found with DOACs versus conventional anticoagulants in CAT patients (RR: 2.77, 95% CI: 1.35-5.68, I2: 0% for RCTs). Analyses of subgroups, based on comparators and follow-up duration, did not significantly affect results.

CONCLUSIONS

In this study, effectiveness and safety of DOACs versus conventional anticoagulants in CAT from OSs are in agreement with those from RCTs, confirming a low risk of recurrent VTE and similar risk of major bleeding in CAT patients receiving DOACs.