Improved early right ventricular function recovery but increased complications with catheter-directed interventions compared with anticoagulation alone for submassive pulmonary embolism

Economic Analysis of Catheter-Directed Thrombolysis for Intermediate-Risk Pulmonary Embolism

BACKGROUND

Pulmonary embolism is associated with a significant burden of morbidity, mortality, and health care costs. Catheter-directed thrombolysis has emerged as a promising option for patients with intermediate-risk pulmonary embolism which aims to improve outcomes over standard anticoagulation.

METHODS

We constructed a decision-analytic model comparing the cost-effectiveness of catheter-directed thrombolysis to anticoagulation alone for the management of intermediate-risk pulmonary embolism. Cost-effectiveness was determined by calculating deaths averted and incremental cost-effectiveness ratios (ICER). Uncertainty was addressed by plotting cost-effectiveness planes and acceptability curves for various willingness-to-pay thresholds. The main outcome was ICER (US dollars/deaths averted).

RESULTS

In the base case analysis, derived using systemic lysis data, the cost associated with catheter-directed thrombolysis was estimated at $22,353 with a probability of survival at 1 month of 0.984. For the anticoagulation alone strategy, the cost was $25,060, and the probability of survival at 1 month was 0.958. Overall, catheter-directed thrombolysis resulted in savings of $104,089 per death averted (ICER,-$104,089 per death averted). Sensitivity analysis revealed that catheter-directed thrombolysis would no longer be cost-effective when its associated mortality is greater than 0.042. In the probabilistic analysis, at a willingness-to-pay of $100,000, catheter-directed thrombolysis had a 63% chance of being cost-effective, and in cost-effectiveness acceptability curves, it was cost-effective in 63%-78% of simulations for a willingness to pay ranging from $0 to $100,000.

CONCLUSIONS

If the assumptions made in our model are shown to be accurate then CDT would be cost-effective and may lead to considerable cost savings if used where clinically appropriate.

Anticoagulant Impact on Clinical Outcomes of Pulmonary Embolism Compared With Thrombolytic Therapy; Meta-Analysis

BACKGROUND

Pulmonary embolism (PE) is a critical condition requiring effective management strategies. Several options are available, including thrombolytic therapy and anticoagulants.

OBJECTIVES

To assess the impact of thrombolytic therapy either combined with anticoagulant (AC) or alone versus AC alone on mortality, recurrence, clinical deterioration, bleeding, and hospital stay.

METHOD

This study included 25 previously published studies from 1990 to 2023, with a total of 12 836 participants. Dichotomous and continuous analysis models were used to evaluate outcomes, with heterogeneity and publication bias tests applied. A random model was used for data analysis. Several databases were searched for the identification and inclusion of studies, such as Ovid, PubMed, Cochrane Library, Google Scholar, and Embase.

RESULTS

For sub-massive PE, CDT plus AC significantly reduced in-hospital, 30-day, and 12-month mortality compared to AC alone, odds ratio (OR) of -0.99 (95% CI [-1.32 to -0.66]), with increased major bleeding risk but no difference in minor bleeding or hospital stay, OR = 0.46, 95% CI [-0.03 to 0.96]). For acute intermediate PE, systemic thrombolytic therapy did not affect all-cause or in-hospital mortality but increased minor bleeding, reduced recurrent PE, and prevented clinical deterioration. The heterogeneity of different models in the current study varied from 0% to 37.9%.

CONCLUSION

The addition of CDT to AC improves mortality outcomes for sub-massive PE but raises the risk of major bleeding. Systemic thrombolytic therapy reduces recurrence and clinical decline in acute intermediate PE despite increasing minor bleeding. Individualized patient assessment is essential for optimizing PE management strategies.

Severe Traumatic Brain Injury and Pulmonary Embolism: Risks, Prevention, Diagnosis and Management

Severe traumatic brain injury (sTBI) is a silent epidemic, causing approximately 300,000 intensive care unit (ICU) admissions annually, with a 30% mortality rate. Despite worldwide efforts to optimize the management of patients and improve outcomes, the level of evidence for the treatment of these patients remains low. The concomitant occurrence of thromboembolic events, particularly pulmonary embolism (PE), remains a challenge for intensivists due to the risks of anticoagulation to the injured brain. We performed a literature review on sTBI and concomitant PE to identify and report the most recent advances on this topic. We searched PubMed and Scopus for papers published in the last five years that included the terms "pulmonary embolism" and "traumatic brain injury" in their title or abstract. Exclusion criteria were papers referring to children, non-sTBI populations, and post-acute care. Our search revealed 75 papers, of which 38 are included in this review. The main topics covered include the prevalence of and risk factors for pulmonary embolism, the challenges of timely diagnosis in the ICU, the timing of pharmacological prophylaxis, and the treatment of diagnosed PE.

Catheter Interventions for Pulmonary Embolism: Mechanical Thrombectomy Versus Thrombolytics

Pulmonary embolism is a debilitating and potentially life-threatening disease characterized by high mortality and long-term adverse outcomes. Traditional treatment options are fraught with serious bleeding risks and incomplete thrombus removal, necessitating the development of innovative treatment strategies. While new interventional approaches offer promising potential for improved outcomes with fewer serious complications, their rapid development and need for more comparative clinical evidence makes it challenging for physicians to select the optimal treatment for each patient among the many options. This review summarizes the current published clinical data for both traditional treatments and more recent interventional approaches indicated for pulmonary embolism. While published studies thus far suggest that these newer interventional devices offer safe and effective options, more data is needed to understand their impact relative to the standard of care. The studies in progress that are anticipated to provide needed evidence are reviewed here since they will be critical for helping physicians make informed treatment choices and potentially driving necessary guideline changes.

A meta-analysis of outcomes of aspiration thrombectomy for high and intermediate-risk pulmonary embolism

BACKGROUND

Aspiration thrombectomy has gained popularity in patients with massive and sub-massive pulmonary embolism (PE) and having contraindications to thrombolysis.

METHODS

A meta-analysis was conducted including studies on aspiration thrombectomy in patients with high-risk and intermediate-risk PE. The pooled odds ratio for efficacy parameters, including change in heart rate, blood pressure and right ventricle/left ventricle (RV/LV) ratio, and safety parameters including major bleeding and stroke, was calculated using a random effects model.

RESULTS

The meta-analysis of 24 selected studies revealed that intermediate and high-risk pulmonary embolism (PE) patients demonstrated significant improvements: modified Miller score odds ratio of 10.60, mean pulmonary artery pressure reduction by 0.04 mm Hg, and an overall all-cause mortality odds ratio of 0.10. Considerable heterogeneity was observed in various outcomes.

CONCLUSION

Aspiration thrombectomy has success rates in both high-risk and intermediate-risk PE, however, procedural risks, including bleeding, must be anticipated.

A comparison of the efficacy and safety between anticoagulation alone and combined with catheter-directed thrombolysis for treatment of pulmonary embolism on outcome: A systematic review and meta-analysis

BACKGROUND

Catheter-directed thrombolysis (CDT) is one of the newest treatment options for submassive pulmonary embolism (sPE). This study will compare the efficacy and safety of catheter-directed thrombolysis (CDT) combine with anticoagulation versus anticoagulation alone (AC) in patients with PE.

METHODS

A database search was conducted using PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov for trials that compared CDT with AC in patients with pulmonary embolism. The primary outcomes was1-year mortality. The secondary outcomes were in-hospital, 30 days, 90 days mortality, in-hospital major and minor bleeding (Thrombolysis in Myocardial Infarction (TIMI) classification), length of hospital stay (LOS), reduction of pulmonary arterial systolic pressure (PASP) and RV/LV diameter ratio.

RESULTS

A total of 16 articles (3 RCTs and 13 non-RCTs) and 10595 patients were included in this study. 2237 patients were in the CDT group and 8358 patients were in the AC group. CDT group was associated with significantly lower in-hospital mortality (2.1% vs 6.2%,OR:0.36, 95%CI:0.26-0.51, p < .00001,I2 = 0%), 30 days mortality (3.1% vs 8.6%,OR:0.39,95%CI:0.23-0.66, p = .0005, I2 = 0%), 90 days mortality (3.8% vs 7.7%,OR:0.49,95%CI:0.29-0.80,p = .005,I2 = 7%), 1-year mortality (6.1% vs 11%, OR:0.51, 95%CI:0.35-0.76, p = .0008,I2 = 36%) compared to AC group, especially in ultrasound-assisted thrombolysis (USAT) subgroup. There were no differences on major bleeding between two groups (1.8% vs 2.2%, OR:1.10, 95%CI:0.61-1.98, p = .75, I2 = 0%). Minor bleeding was significantly higher in CDT group than AC group (6.2% vs 3.8%, OR:1.93,95%CI:1.27-2.94.66, p = .002, I2 = 1%). CDT group significantly reduced PASP (WMD:11.90,95%CI:6.45-17.35, p < .0001, I2 = 72%) and RV/LV (WMD:0.17,95%CI:0.04-0.30, p = .009, I2 = 69%) rapidly than AC group after treatment. LOS was similar between two groups (WMD:0.02,95%CI: -0.68-0.73, p = .95, I2 = 51%).

CONCLUSION

Results thus confirmed that CDT reduced in-hospital, 30 days, 90 days and 1-year all-cause mortality in patients with sPE compared to AC, particularly in USAT subgroup. Nonetheless, CDT group was associated with a higher risk of minor bleeding.

Comparative Outcomes of Catheter-Directed Thrombolysis Plus Systemic Anticoagulation Versus Systemic Anticoagulation Alone in the Management of Intermediate-Risk Pulmonary Embolism in a Systematic Review and Meta-Analysis

There are limited and conflicting data on the initial management of intermediate-risk (or submassive) pulmonary embolism (PE). This study sought to compare the outcomes of catheter-directed thrombolysis (CDT) in combination with systemic anticoagulation (SA) to SA alone. A systematic search was conducted in MEDLINE, EMBASE, PubMed, and the Cochrane databases from inception to March 1, 2023 for studies comparing the outcomes of CDT + SA versus SA alone in intermediate-risk PE. The outcomes were in-hospital, 30-day, 90-day, and 1-year mortality; bleeding; blood transfusion; right ventricular recovery; and length of stay. Random-effects models was used to calculate the pooled incidence and risk ratios (RRs) with 95% confidence intervals (CIs). A total of 15 (2 randomized and 13 observational) studies with 10,549 (2,310 CDT + SA and 8,239 SA alone) patients were included. Compared with SA, CDT + SA was associated with significantly lower in-hospital mortality (RR 0.41, 95% CI 0.30 to 0.56, p <0.001), 30-day mortality (RR 0.34, 95% CI 0.18 to 0.67, p = 0.002), 90-day mortality (RR 0.34, 95% CI 0.17 to 0.67, p = 0.002), and 1-year mortality (RR 0.58, 95% CI 0.34 to 0.97, p = 0.04). There were no significant differences between the 2 cohorts in the rates of major bleeding (RR 1.39, 95% CI 0.72 to 2.68, p = 0.56), minor bleeding (RR 1.83, 95% CI 0.97 to 3.46, p = 0.06), and blood transfusion (RR 0.34, 95% CI 0.10 to 1.15, p = 0.08). In conclusion, CDT + SA is associated with significantly lower short-term and long-term all-cause mortality, without any differences in major/minor bleeding, in patients with intermediate-risk PE.

Catheter-directed thrombolysis compared with systemic thrombolysis and anticoagulation in patients with intermediate- or high-risk pulmonary embolism: systematic review and network meta-analysis

BACKGROUND

Therapeutic options for intermediate- or high-risk pulmonary embolism (PE) include anticoagulation, systemic thrombolysis and catheter-directed thrombolysis (CDT); however, the role of CDT remains controversial. We sought to compare the efficacy and safety of CDT with other therapeutic options using network meta-analysis.

METHODS

We searched PubMed (MEDLINE), Embase, ClinicalTrials.gov and Cochrane Library from inception to Oct. 18, 2022. We included randomized controlled trials and observational studies that compared therapeutic options for PE, including anticoagulation, systemic thrombolysis and CDT among patients with intermediate- or high-risk PE. The efficacy outcome was in-hospital death. Safety outcomes included major bleeding, intracerebral hemorrhage and minor bleeding.

RESULTS

We included data from 44 studies, representing 20 006 patients. Compared with systemic thrombolysis, CDT was associated with a decreased risk of death (odd ratio [OR] 0.43, 95% confidence interval [CI] 0.32-0.57), intracerebral hemorrhage (OR 0.44, 95% CI 0.29-0.64), major bleeding (OR 0.61, 95% CI 0.53-0.70) and blood transfusion (OR 0.46, 95% CI 0.28-0.77). However, no difference in minor bleeding was observed between the 2 therapeutic options (OR 1.11, 95% CI 0.66-1.87). Compared with anticoagulation, CDT was also associated with decreased risk of death (OR 0.36, 95% CI 0.25-0.52), with no increased risk of intracerebral hemorrhage (OR 1.33, 95% CI 0.63-2.79) or major bleeding (OR 1.24, 95% CI 0.88-1.75).

INTERPRETATION

With moderate certainty of evidence, the risk of death and major bleeding complications was lower with CDT than with systemic thrombolysis. Compared with anticoagulation, CDT was associated with a probable lower risk of death and a similar risk of intracerebral hemorrhage, with moderate certainty of evidence. Although these findings are largely based on observational data, CDT may be considered as a first-line therapy in patients with intermediate- or high-risk PE.

PROTOCOL REGISTRATION

PROSPERO - CRD42020182163.

Acute outcomes for the full US cohort of the FLASH mechanical thrombectomy registry in pulmonary embolism

BACKGROUND

Evidence supporting interventional pulmonary embolism (PE) treatment is needed.

AIMS

We aimed to evaluate the acute safety and effectiveness of mechanical thrombectomy for intermediate- and high-risk PE in a large real-world population.

METHODS

FLASH is a multicentre, prospective registry enrolling up to 1,000 US and European PE patients treated with mechanical thrombectomy using the FlowTriever System. The primary safety endpoint is a major adverse event composite including device-related death and major bleeding at 48 hours, and intraprocedural adverse events. Acute mortality and 48-hour outcomes are reported. Multivariate regression analysed characteristics associated with pulmonary artery pressure and dyspnoea improvement.

RESULTS

Among 800 patients in the full US cohort, 76.7% had intermediate-high risk PE, 7.9% had high-risk PE, and 32.1% had thrombolytic contraindications. Major adverse events occurred in 1.8% of patients. All-cause mortality was 0.3% at 48-hour follow-up and 0.8% at 30-day follow-up, with no device-related deaths. Immediate haemodynamic improvements included a 7.6 mmHg mean drop in mean pulmonary artery pressure (-23.0%; p<0.0001) and a 0.3 L/min/m2 mean increase in cardiac index (18.9%; p<0.0001) in patients with depressed baseline values. Most patients (62.6%) had no overnight intensive care unit stay post-procedure. At 48 hours, the echocardiographic right ventricle/left ventricle ratio decreased from 1.23±0.36 to 0.98±0.31 (p<0.0001 for paired values) and patients with severe dyspnoea decreased from 66.5% to 15.6% (p<0.0001).  Conclusions: Mechanical thrombectomy with the FlowTriever System demonstrates a favourable safety profile, improvements in haemodynamics and functional outcomes, and low 30-day mortality for intermediate- and high-risk PE.

Percutaneous Management of High-Risk Pulmonary Embolism

Acute pulmonary embolism (PE) leads to an abrupt increase in pulmonary vascular resistance and right ventricular afterload, and when significant enough, can result in hemodynamic instability. High-risk PE is a dire cardiovascular emergency and portends a poor prognosis. Traditional therapeutic options to rapidly reduce thrombus burden like systemic thrombolysis and surgical pulmonary endarterectomy have limitations, both with regards to appropriate candidates and efficacy, and have limited data demonstrating their benefit in high-risk PE. There are growing percutaneous treatment options for acute PE that include both localized thrombolysis and mechanical embolectomy. Data for such therapies with high-risk PE are currently limited. However, given the limitations, there is an opportunity to improve outcomes, with percutaneous treatments options offering new mechanisms for clot reduction with a possible improved safety profile compared with systemic thrombolysis. Additionally, mechanical circulatory support options allow for complementary treatment for patients with persistent instability, allowing for a bridge to more definitive treatment options. As more data develop, a shift toward a percutaneous approach with mechanical circulatory support may become a preferred option for the management of high-risk PE at tertiary care centers.

Improved long-term outcomes with catheter-directed therapies over medical management in patients with submassive pulmonary embolism-a retrospective matched cohort study

BACKGROUND

The benefit of catheter-directed therapy (CDT) for submassive pulmonary embolism (sPE) has been the subject of debate. We sought to determine the short- and long-term mortality and outcomes of CDT compared with anticoagulation for patients with sPE.

METHODS

We performed a single healthcare network, multihospital, retrospective cohort study of hospitalizations for sPE from 2012 to 2019. sPE was defined as the presence of right heart strain or elevated biomarkers (troponin I or B-type natriuretic peptide). Patients with massive PE and those who had undergone systemic thrombolysis were excluded. The sPE groups included therapeutic anticoagulation alone or anticoagulation plus CDT (ie, thrombolysis or suction thrombectomy). The primary outcome was mortality at 1, 3, and 5 years. The other measured outcomes included PE-related death, short term mortality (30 days and 3 and 6 months), 30-day treatment-related complications (eg, bleeding, transfusion, stroke), chronic thromboembolic pulmonary hypertension, and 6-minute walk test at 1 year. After 1:1 nearest-neighbor propensity score matching, Kaplan-Meier survival plots were generated, and the treatment groups were compared using log-rank testing. We used Cox multivariate analysis to evaluate the outcomes after clustering at the hospital level, generating matched hazard ratios (mHRs) with associated 95% confidence intervals (CIs).

RESULTS

Of 6746 sPE hospitalizations, the patients who had received CDT were younger (age, 58.9 ± 15.5 years vs 61.5 ± 17.4 years; P = .004), were more frequently White (92.5% vs 85.7%; P < .001), and had presented with a higher mean heart rate (104.6 bpm vs 94.9 bpm; P < .001), lower median systolic blood pressure (129 mm Hg vs 135 mm Hg; P < .001), and a greater incidence of right heart strain (79.2% vs 20.3%; P < .001). A total of 470 patients were matched, with 235 in the CDT group and 235 in the anticoagulation-only group. CDT was associated with a lower risk of mortality compared with anticoagulation at 1 year (7.6% vs 9.8%; mHR, 0.77; 95% CI, 0.65-0.92; P = .004), 3 years (11.1% vs 16.6%; mHR, 0.64; 95% CI, 0.55-0.73; P < .001), and 5 years (14.5% vs 19.1%; mHR, 0.71; 95% CI, 0.66-0.77; P < .001). Anticoagulation alone resulted in a greater incidence of PE-related deaths at 1, 3, and 5 years. The mortality at 30 days and 3 months was similar; however, CDT had resulted in better survival at 6 months (mHR, 0.81; 95% CI, 0.68-0.97; P = .02). No differences were found between the two groups in the incidence of bleeding complications at 30 days, development of chronic thromboembolic pulmonary hypertension, or the mean walking distance at 1 year.

CONCLUSIONS

CDT plus anticoagulation for sPE was associated with improved long-term survival compared with anticoagulation alone, with a lower incidence of PE-related death and a low complication rate. CDT should be considered for select patients with sPE given its survival benefit.

Meta-Analysis Comparing Catheter-Directed Thrombolysis Versus Systemic Anticoagulation Alone for Submassive Pulmonary Embolism

The optimal therapy for submassive pulmonary embolism (sPE), defined by right ventricular dysfunction without hemodynamic instability, is uncertain. We conducted a systematic review and meta-analysis to compare the outcomes of catheter-directed thrombolysis (CDT) versus systemic anticoagulation (SA) alone in patients with sPE. We searched PubMed, EMBASE, Cochrane, ClinicalTrials.gov, and Google Scholar (from inception through May 2022) for studies comparing outcomes of CDT versus SA in sPE. Studies were identified, and data were extracted by 2 independent reviewers. We used a random-effects model to calculate risk ratios (RRs) with 95% confidence intervals (CIs). Outcomes included in-hospital, 30-day, 90-day, and 1-year mortality, major and minor bleeding, and need for blood transfusion. A total of 12 studies (1 randomized, 11 observational) with 9,789 patients were included. Compared with SA, CDT was associated with significantly lower in-hospital mortality (RR 0.41, 95% CI 0.30 to 0.56, p <0.00001), 30-day mortality (RR 0.37, 95% CI 0.18 to 0.73, p = 0.004), 90-day mortality (RR 0.36, 95% CI 0.17 to 0.72, p = 0.004), and a tendency toward lower 1-year mortality (RR 0.56, 95% CI 0.29 to 1.05, p = 0.07). The risks of major bleeding (RR 1.31, 95% CI 0.57 to 3.01, p = 0.53), minor bleeding (RR 1.67, 95% CI 0.77 to 3.63, p = 0.20), and the rates of blood transfusion (RR 0.34, 95% CI 0.10 to 1.15, p = 0.08) were similar between the 2 strategies. In conclusion, in patients with sPE, CDT is associated with significantly lower in-hospital, 30-day, and 90-day mortality and a tendency toward lower 1-year mortality with similar bleeding rates compared with SA. This study expands the evidence supporting CDT as first-line therapy for sPE, and randomized controlled trials are indicated to confirm our findings.

A Comparative Analysis of Catheter Directed Thrombolysis with Anticoagulation Alone or Systemic tPA in Acute Pulmonary Embolism with Cor Pulmonale

Background

Pulmonary embolism (PE) with cor pulmonale causes considerable mortality and morbidity. Randomized trials have failed to show a mortality difference between treatment modalities including anticoagulation (AC), Catheter directed thrombolysis (CDT) and systemic tPA (tissue plasminogen activator).

Methods

This is a cross-sectional retrospective case-control study utilizing the 2017 National Inpatient Sample (NIS). Patients admitted with acute PE with cor pulmonale were divided into groups based on whether they received anticoagulation, CDT or systemic tPA based on appropriate ICD-10 PCS codes. The AC group and CDT group were compared using univariate and multivariate analyses after adjusting for age, gender, race, comorbidities, insurance status and Charlson comorbidity index (CCI). Secondary outcomes included factors influencing length of stay (LOS) and total charges incurred. Similar analyses were done to compare the CDT group with the tPA group.

Results

In 2017, 13240 patients were admitted with acute PE and cor pulmonale, of whom 18% underwent CDT, 10% underwent systemic tPA and 72% underwent AC alone. Patients who received CDT over AC alone were significantly younger (61.5 vs. 65.5, p = 0.00). Mortality rate overall was 4.8% with tPA group, CDT group and AC alone group having a 11.2%, 3.0% and 4.4% mortality rate respectively. On multivariate analyses, there was no significant mortality difference between the CDT and AC groups (aOR 0.61, 0.34-1.1 95%CI, p = 0.103). Patients with liver disease had significantly higher mortality while obese patients had a significantly lower mortality after adjusting for treatment strategy and confounders. Length of stay (LOS) was not significantly different between the groups however, compared to AC alone, patients who underwent CDT or tPA incurred significantly higher total hospital charges.

Conclusions

CDT offers an attractive alternative to tPA therapy; however, our study does not show an in-hospital mortality benefit. More studies are required to guide patient selection prior to establishing treatment protocols.

Catheter-directed Thrombolysis versus Systemic Anticoagulation for Submassive Pulmonary Embolism: A Meta-Analysis

BACKGROUND

The optimal therapy for submassive pulmonary embolism remains in question. The following meta-analysis compiles the current evidence comparing Catheter-Directed Thrombolysis (CDT) versus Systemic Anticoagulation (SA).

METHODS

An electronic search through PubMed and Google scholar revealed studies comparing CDT versus SA in terms of mortality and major bleeding events. Thirty-day, 90-day, and one-year mortality results were analyzed.

RESULTS

Six studies were included in the meta-analysis. Thirty-day and one-year mortality were less with CDT compared to SA (OR 0.27 [CI 0.11-0.67]; and OR 0.50 [CI 0.28-0.89]). Ninety-day mortality was similar between the two methods (OR 0.57 [CI 0.17-1.92]). Compilation of all studies reporting at least greater than 30-day mortality revealed less mortality with CDT (OR 0.51 [0.30-0.86]). Major bleeding was similar between the two treatments (OR 1.63 [CI 0.63-4.20]).

CONCLUSION

CDT has less 30-day and 1-year mortality with equivalent rates of major bleeding compared to SA for treatment of submassive pulmonary embolism.

Repeat angiography in patients undergoing conventional catheter-directed thrombolysis for submassive pulmonary embolism: a large single-center experience

PURPOSE

Few studies have examined conventional catheter directed thrombolysis (CDT) for the treatment of submassive pulmonary embolism (PE). Moreover, angiographic resolution of thrombus burden following CDT has infrequently been characterized. This study describes a single-center experience treating submassive PE with CDT while utilizing repeat angiography to determine treatment efficacy.

METHODS

A retrospective analysis of 140 consecutive patients who underwent CDT for submassive PE from December 2012 to June 2019 was performed. Angiographic resolution of thrombus burden after CDT was reported as high (>75%), moderate (51-75%), low (26-50%), or insignificant (≤25%). All angiograms were reviewed by two interventional radiologists. Secondary endpoints included reduction in pulmonary artery pressure (PAP) and clinical outcomes. Bleeding events were classified according to the Society of Interventional Radiology (SIR) adverse event criteria.

RESULTS

CDT was performed in 140 patients with a mean rtPA dose of 25.3 mg and a mean treatment time of 26.0 hours. Angiographic resolution of thrombus burden was high in 70.0%, moderate in 19.3%, low in 5.7%, and insignificant in 3.6%; in 2 patients (1.4%) repeat angiography was not performed. Systolic PAP was reduced (47 vs. 35 mmHg, p < 0.001), mean PAP was reduced (25 vs 21 mmHg, p < 0.001), and 129 patients (92.1%) improved clinically. Patients with high or moderate resolution of thrombus burden had a clinical improvement rate of 95.2%, while patients with low or insignificant thrombus burden resolution had a clinical improvement rate of 76.9% (p=0.011). Ten patients (7.1%) had hemodynamic or respiratory decompensation requiring mechanical ventilation, systemic thrombolysis, cardiopulmonary resuscitation, or surgical intervention. Seven patients (5.0%) experienced moderate bleeding events and one patient (0.7%) with metastatic disease developed severe gastrointestinal bleeding that resulted in death. Thirty-day mortality was 1.4%.

CONCLUSION

In patients with submassive PE undergoing CDT, angiographic resolution of thrombus burden is a safe and directly observable metric that can be used to determine procedural success. In this study, CDT with repeat angiography was associated with a 5.7% bleeding event rate and thirty-day mortality of 1.4%.

Safety and efficacy of catheter-directed therapy versus anticoagulation alone in a higher-risk acute pulmonary embolism population

There is little data comparing safety and efficacy outcomes in patients with pulmonary embolism (PE) receiving catheter directed therapies (CDT) compared to a similar-risk cohort of PE patients receiving anticoagulation alone. 1094 patients with acute PE were studied. CDT and conservatively-managed patients were compared using propensity score matching to assess safety outcomes, which included bleeding and acute kidney injury at 2 and 7 days after PE diagnosis. Efficacy outcomes included change in vital signs over 72 h and in-hospital mortality. PE patients with RV strain who underwent CDT (n = 76) had more bleeding at 2 days (additional 1.04 g/dL loss, 95% CI − 1.48 to − 0.60, p < 0.001) and 7 days (additional 1.36 g/dL loss, 95% CI − 1.88 to − 0.84, p < 0.001) compared to those receiving anticoagulation alone (n = 303). There was a significant increase in creatinine at 2 days (additional 0.22 mg/dL elevation, 95% CI 0.02 to 0.42, p = 0.03), but not at 7 days (additional 0.12 mg/dL elevation, 95% CI − 0.11 to 0.35, p = 0.30). In-hospital mortality for patients receiving CDT versus anticoagulation alone was similar (OR 1.21, 95% CI 0.53 to 2.77; p = 0.65). In patients with baseline abnormal vital signs who received CDT versus anticoagulation alone, heart rate, respiratory rate and oxygen requirement improved significantly faster and to levels closer to normal (p ≤ 0.001). CDT was associated with a small but increased risk of bleeding, but no significant worsening of renal function. CDT may be associated with more rapid improvements in heart rate, respiratory rate, and oxygen requirement.

Outcomes of catheter-directed interventions in high-risk pulmonary embolism-a retrospective analysis

BACKGROUND

First-line treatment of high-risk pulmonary embolism with persistent hypotension and/or signs of shock is intravenous thrombolysis. However, if thrombolysis is contraindicated due to risk of serious bleeding, or if it yields insufficient effect, surgical thrombectomy or catheter-directed intervention (CDI) plus anticoagulation is recommended. The aim of this study was to assess the outcomes of the CDI modality introduced in a tertiary referral centre in 2013.

METHODS

Retrospective comparison between patients treated with CDI plus anticoagulation (n = 22) and patients treated with anticoagulation only (n = 23) as used before the CDI technique was available. The main outcomes of interest were 90-day survival and reduction of right to left ventricle diameter (RV/LV) ratio, using the Fischer's exact test and a mixed model, respectively, for statistical analysis.

RESULTS

Ninety-day survival was 59% after CDI and 61% after anticoagulation only; P = .903. The rate of RV/LV ratio reduction was 0.4 units higher per 24 hours in the CDI group (median 2.1 pre-treatment), than in the anticoagulation only group (median 1.3 pre-treatment); P = .007.

CONCLUSION

In patients with high-risk pulmonary embolism, 90-day survival was similar after treatment with CDI plus anticoagulation compared to anticoagulation only. The mean reduction in RV/LV ratio was larger in the CDI group. Our results support the use of CDI in selected patients, respecting the limitations and potential side effects of each technical device used.

Catheter-Directed Thrombolysis in Submassive Pulmonary Embolism and Acute Cor Pulmonale

Treatment of submassive (intermediate-risk) pulmonary embolism (PE), defined as hemodynamically stable with right ventricular (RV) dysfunction, showed lower in-hospital all-cause mortality with intravenous thrombolytic therapy than with anticoagulants, but at an increased risk of major bleeding. The present investigation was performed to test whether catheter-directed thrombolysis reduces mortality without increasing bleeding in submassive PE. This was a retrospective cohort study based on administrative data from the Nationwide Inpatient Sample. In 2016, 13,130 patients were hospitalized with PE and acute cor pulmonale, were stable, and treated with catheter-directed thrombolysis in 1,500 (11%) or anticoagulants alone in 11,630 (89%). Mortality was lower with catheter-directed thrombolysis than with anticoagulants in unmatched patients, 35 of 1,500 (2.3%) compared with 755 of 11,630 (6.5%; p <0.0001) and in matched patients, 30 of 1,260 (2.4%) compared with 440 of 6,910 (6.4%; p <0.0001). Time-dependent analysis showed catheter-directed thrombolysis reduced mortality if administered within the first 3 days. Patients with saddle PE treated with anticoagulants had lower mortality than non-saddle PE, 75 of 1,730 (4.3%) compared with 680 of 9,900 (6.9%; p < 0.0001) in unmatched patients and 45 of 1,305 (3.4%) compared with 395 of 5,605 (7.0%; p < 0.0001) in matched patients. Mortality was not lower with inferior vena cava filters either in those who received catheter-directed thrombolysis or those treated with anticoagulants. There were no fatal or nonfatal adverse events associated with catheter-directed thrombolysis. In conclusion, patients with submassive PE appear to have lower in-hospital all-cause mortality with catheter-directed thrombolysis administered within 3 days than with anticoagulants, and risks are low.

First year experience of a pulmonary embolism response team with comparisons of outcomes between catheter directed therapy versus standard anticoagulation

Objectives: The Pulmonary Embolism Response Team (PERT) model is now widely adopted in many institutions to provide multidisciplinary care for patients with acute pulmonary embolism (PE). However, descriptive experiences of PERT operations and studies on clinical outcomes remain limited.Methods: We performed a retrospective review of PERT activations at an academic tertiary care center, with secondary aims to study outcomes associated with performing catheter directed therapies (CDT).Results: The intermediate high-risk PE category was most frequent (n = 40, 76.9%) among the 52 total cases evaluated during the study period. There was one in-hospital mortality, associated with hospice admission for a non-PE diagnosis. Six patients (11.5%) experienced a bleeding complication of any severity. Anticoagulation (AC) alone was recommended in 30 patients (57.7%) and CDT was performed in 16 patients (30.8%). There were no significant differences in patient characteristics or disease severity between patients in the AC group versus the CDT group, except for a higher prevalence of malignancy in the AC group (p = 0.037). Patients who underwent CDT demonstrated a lower, albeit non-significant, median intensive care unit (ICU) length of stay (LOS) (3 vs. 4 days, p = 0.34) and hospital LOS (4 vs. 5 days, p = 0.25), as compared to patients receiving AC alone. Bleeding rates were similar between the two groups (6.7% vs. 6.3%, p = 1.0).Conclusions: Adoption of the PERT model at an academic tertiary care center was associated with acceptably low rates of mortality and bleeding, similar to other published studies. Performing CDT in select patients under PERT consultation may be associated with shorter ICU and hospital LOS; however, larger studies are needed to validate this finding.

Systematic Review: The Role of Thrombolysis in Intermediate-Risk Pulmonary Embolism

BACKGROUND

This systemic review provides practicing emergency physicians updated information about the role of thrombolysis in the treatment of intermediate-risk pulmonary embolism.

METHODS

A PubMed literature search from January 1, 2005 to December 31, 2018 was conducted and limited to human clinical trials written in English with relevant keywords. High-quality studies were identified and then underwent a structured review. Recommendations are made based on the literature review.

RESULTS

Sixty-three articles met criteria for rigorous review, of which 13 were appropriate for citation in this review. Of these 13, there were 6 prospective studies and 7 retrospective studies.

CONCLUSIONS

Thrombolysis, either catheter-directed or systemic, is a treatment option in the management of patients with intermediate-risk pulmonary embolism and a high likelihood of clinical deterioration. Each method of thrombolysis carries risks and benefits. Based on the available evidence, transfer to a facility for the purpose of catheter-directed thrombolysis is not recommended.

Catheter-directed Thrombolysis for Intermediate-Risk Pulmonary Embolism

Intermediate-risk pulmonary embolism is common and carries a risk of progression to hemodynamic collapse and death. Catheter-directed thrombolysis is an increasingly used treatment option, based largely on the assumptions that it is more efficacious than anticoagulation alone and safer than systemic thrombolysis. In this review, we critically analyze the published data regarding catheter-directed thrombolysis for the treatment of intermediate-risk pulmonary embolism. Catheter-directed thrombolysis reduces right heart strain and lowers pulmonary artery pressures more quickly than anticoagulation alone. The mortality for patients with intermediate-risk pulmonary embolism treated with catheter-directed thrombolysis is low, between 0% and 4%. However, similarly low mortality is seen with anticoagulation alone. Catheter-directed thrombolysis appears to be safer than systemic thrombolysis, and procedural complications are uncommon. Bleeding risk appears to be slightly higher than with anticoagulation alone. Randomized, controlled trials are needed to compare the efficacy and safety of catheter-directed thrombolysis versus anticoagulation for intermediate-risk pulmonary embolism. There is no evidence that catheter-directed thrombolysis decreases the incidence of chronic thromboembolic pulmonary hypertension. There is no evidence from clinical studies that ultrasound-assisted thrombolysis is more effective or safer than standard catheter-directed thrombolysis.

Predictors of failure and complications of catheter-directed interventions for pulmonary embolism

OBJECTIVE

Catheter-directed interventions (CDIs) are increasingly performed for acute pulmonary embolism (PE) as they are presumed to provide similar therapeutic benefits to systemic thrombolysis while decreasing the dose of thrombolytic required and the associated risks. This study aimed to identify factors associated with CDI failure and to describe anticipated complications.

METHODS

Consecutive patients who underwent CDI for massive or submassive PE between 2009 and 2015 were identified; outcomes and complications were retrospectively collected. CDI clinical failure was defined as major bleeding, perioperative stroke or other major adverse procedure-related event, decompensation for submassive or persistent shock for massive PE, need for surgical thromboembolectomy, or in-hospital death. Univariate analysis was used to study the factors associated with CDI failure.

RESULTS

There were 102 patients who received a CDI during the study period (36 standard catheter thrombolysis, 60 ultrasound assisted, 6 other; age, 59.2 ± 15.9 years; male, 50 [49.0%]; massive PE, 14 [13.7%]). Five patients (4.9%) had a major contraindication and 15 patients (14.7%) had a minor contraindication to systemic thrombolysis. The mean alteplase dose was 28.2 ± 18.8 mg (range, 0-123 mg; three patients had already received systemic lysis). CDI failure occurred in 15 patients (14.7%; 7 in massive PE, 8 in submassive PE). Of these patients, seven had major bleeding events, whereas eight patients decompensated. Ten (9.8%) patients had minor bleeding events (four access related). Factors associated with CDI failure and major bleeding included massive PE, age ≥70 years, and major contraindication to thrombolytics. Both failures and bleeding events were independent of lysis dose and CDI technique.

CONCLUSIONS

CDIs for acute PE are not risk-free procedures, and their use should be individualized on the basis of a risk-benefit ratio. Particularly for patients with major contraindications to systemic thrombolytics, CDIs should be used selectively. Lytic dose, within the low-volume range administered in CDI, and type of CDI seem to have no impact on adverse events.

Local low-dose urokinase thrombolysis for the management of haemodynamically stable pulmonary embolism with right ventricular dysfunction

AIMS

The aim of this study was to evaluate the effectiveness of local low-dose urokinase thrombolysis (LLDUT) in haemodynamically stable pulmonary embolism with right ventricular dysfunction (RVD).

METHODS AND RESULTS

This was a prospective study. LLDUT with a 200,000 IU bolus followed by a 100,000 IU/hr infusion was given. Treatment duration was determined through radiological control performed 48-72 hrs into treatment. A follow-up echocardiogram was performed within seven days after LLDUT completion. Evolution of thrombus burden, pulmonary artery pressures (PAP) and RVD were studied, and haemorrhagic complications and mortality were recorded. Eighty-seven patients were included (62.5±16.5 years). In 67 patients (77%), the baseline echocardiogram showed mild-to-severe RVD, a dilated right ventricle (diameter: 44.4±6.2 mm) and a decreased tricuspid annular plane systolic excursion (14 mm [12-17]). Seventy-six patients (87.4%) experienced radiological improvement. Initially high PAP (mmHg) decreased after LLDUT: systolic 52.4 vs. 35.2 (17.2 [95% CI: 14.5-19.9]; p<0.0001), mean 34.2 vs. 23.5 (10.7 [95% CI: 9.0-12.5]; p<0.0001) and diastolic 23.9 vs. 16.0 (7.9 [95% CI: 6.1-9.7]; p<0.0001). Follow-up echocardiography showed overall improvement of RVD. No life-threatening haemorrhagic complications were reported. Six-month survival was 96.5%.

CONCLUSIONS

LLDUT rapidly decreased thrombus burden and PAP, improving right ventricular function, and was not associated with any life-threatening complications or pulmonary embolism (PE)- or treatment-related mortality.

Fulminant pulmonary embolism with fatal outcome in a patient with low clinical prediction scores

We present a case of a 72-year-old man with submassive acute pulmonary thromboembolism. Pulmonary embolism severity index Score and common clinical risk stratification recommended systemic anticoagulation and a clinical course without complications was expected. A primary reperfusion strategy was not indicated by the current guidelines. Under established anticoagulation, the patient was found in cardiac arrest immediately after mobilisation from the bed the next morning. Right heart catheterisation under ongoing resuscitation revealed a complete obstruction of the right pulmonary artery by a big thrombus. Catheter-directed intervention trying to bypass the thrombus with interventional guidewires failed. Ultimately, the patient died from acute right heart failure. The current case raises concern that the prediction scores available for pulmonary embolism may insufficiently predict short-term outcome in isolated patients.

Catheter-directed interventions compared with systemic thrombolysis achieve improved ventricular function recovery at a potentially lower complication rate for acute pulmonary embolism

OBJECTIVE

Catheter-directed interventions (CDIs) are increasingly performed for acute pulmonary embolism (PE) as they are presumed to provide similar therapeutic benefits to systemic thrombolysis (ST) while decreasing the associated complications. The purpose of this study was to compare outcomes between CDI and ST.

METHODS

Consecutive patients who underwent CDIs or ST for massive or submassive PE between 2006 and 2016 were identified. Clinical and echocardiographic parameters at baseline and after treatment were recorded. Clinical success was defined as decompensation resolution (or prevention) without major bleeding, stroke, other major treatment-related event, or in-hospital death. The χ² test and t-test were used for between-groups comparisons.

RESULTS

There were 213 patients who received CDIs (standard catheter thrombolysis in 56, ultrasound-assisted thrombolysis in 146, suction thrombectomies in 10, and pharmacomechanical thrombolysis in 1) and 104 patients who received ST (94 high dose [100 mg], 10 low dose [50 mg]). At baseline, CDI and ST groups had comparable echocardiographic parameters, demographics, and comorbidities, except for PE type (massive PE, 8.5% for CDIs vs 69.2% for ST; P < .001), age (60.2 ± 14.9 years for CDIs vs 55.9 ± 17.3 years for ST; P = .023), and renal function (glomerular filtration rate, 78.1 ± 33.7 mL/min/1.73 m² for CDIs vs 64.1 ± 35.2 mL/min/1.73 m² for ST; P = .001). Without stratifying per PE type, CDIs had a higher clinical success rate (87.8% vs 66.3%; P < .001) and a lower rate of major bleed (8.0% vs 19.2%; P = .003), stroke (1.4% vs 4.8%; P = .120), and death (1.4% vs 13.5%; P < .001). On stratifying by PE type, there was no difference in clinical success between groups. The mean reduction in right ventricular/left ventricular diameter ratio between baseline and the first post-treatment echocardiographic examination (within 30 days) was significantly higher for CDI (0.27 ± 0.20 vs 0.18 ± 0.15; P = .037). Beyond 30 days, there was no echocardiographic difference between groups. There was no significant difference in clinical outcomes and echocardiographic parameters between standard and ultrasound-assisted CDIs.

CONCLUSIONS

CDIs provide improved recovery of right ventricular function compared with ST. Major bleeding and stroke complications may be lower, but larger studies are needed to validate this. CDIs are complementary to ST, and their use should be individualized on the basis of the patients' clinical presentation, risk profile, and local resources.

Rationale for catheter directed therapy in pulmonary embolism

Pulmonary embolism (PE) is a widespread health concern associated with major morbidity and mortality. Catheter directed therapy (CDT) has emerged as a treatment option for acute PE adding to the current potential options of systemic thrombolysis or anticoagulation. The purpose of this review is to understand the rationale and indications for CDT in patients with PE. While numerous studies have shown the benefits of systemic thrombolysis compared to standard anticoagulation, these are balanced by the increased risk of major bleeding. With this in mind, CDT has the potential to offer the benefits of systemic thrombolysis and in theory, a reduced risk of bleeding. This article will review current treatment guidelines in both massive and submassive PE evaluating both short and long term benefits. The role of CDT will be highlighted, with an emphasis on efficacy and safety.

Ekosonic Endovascular System (EKOS) in a trauma patient with intracranial bleed, recent major surgery, and massive pulmonary embolus: A case report

Pulmonary embolism is a life-threatening condition treated with anticoagulation and systemic thrombolysis when appropriate. In patients with contraindications to thrombolysis, catheter-directed thrombolysis may be considered. Here, we present a patient with massive pulmonary embolus and 3 contraindications to systemic thrombolysis who was successfully treated with pharmacomechanical thrombolysis using the Ekosonic Endovascular System.

A pulmonary embolism response team's initial 20 month experience treating 87 patients with submassive and massive pulmonary embolism

Pulmonary Embolism Response Teams (PERTs) have emerged to provide rapid multidisciplinary assessment and treatment of PE patients. However, descriptive institutional experience and preliminary outcomes data from such teams are sparse. PERT activations were identified through a retrospective review. Only confirmed submassive or massive PEs were included in the data analysis. In addition to baseline variables, the therapeutic intervention, length of stay (LOS), in-hospital mortality, and bleeding rate/severity were recorded. A total of 124 PERT activations occurred over 20 months: 43 in the first 10 months and 81 in the next 10. A total of 87 submassive (90.8%) and massive (9.2%) PE patients were included. The median age was 65 (51-75 IQR) years. Catheter-directed thrombolysis (CDT) was administered to 25 patients, systemic thrombolysis (ST) to six, and anticoagulation alone (AC) to 54. The median ICU stay and overall LOS were 6 (3-10 IQR) and 7 (4-14 IQR) days, respectively, with no association with any variables except a brain natriuretic peptide (BNP) >100 pg/mL ( p=0.008 ICU LOS; p=0.047 overall LOS). Twelve patients (13.7%) died in the hospital, nine of whom had metastatic or brain cancer, with a median overall LOS of 13 (11-17 IQR) days. There were five major bleeds: one in the CDT group, one in the ST group, and three in the AC group. Overall, (1) PERT activations increased after the first 10 months; (2) BNP >100 pg/mL was associated with a longer LOS; (3) rates of mortality and bleeding did not correlate with treatment; and (4) the majority of in-hospital deaths occurred in patients with advanced cancer.