Management of pulmonary embolism with rheolytic thrombectomy

Disentangling the phenotypic patterns of hypertension and chronic hypotension

OBJECTIVE

2017 blood pressure (BP) categories focus on cardiac risk. We hypothesize that studying the balance between mechanisms that increase or decrease BP across the medical phenome will lead to new insights. We devised a classifier that uses BP measures to assign individuals to mutually exclusive categories centered in the upper (Htn), lower (Hotn) and middle (Naf) zones of the BP spectrum; and examined the epidemiologic and phenotypic patterns of these BP-categories.

METHODS

We classified a cohort of 832,560 deidentified electronic health records by BP-category; compared the frequency of BP-categories and four subtypes of Htn and Hotn by sex and age-decade; visualized the distributions of systolic, diastolic, mean arterial and pulse pressures stratified by BP-category; and ran Phenome-wide Association Studies (PheWAS) for Htn and Hotn. We paired knowledgebases for hypertension and hypotension and computed aggregate knowledgebase status (KB-status) indicating known associations. We assessed alignment of PheWAS results with KB-status for phecodes in the knowledgebase, and paired PheWAS correlations with KB-status to surface phenotypic patterns.

RESULTS

BP-categories represent distinct distributions within the multimodal distributions of systolic and diastolic pressure. They are centered in the upper, lower, and middle zones of mean arterial pressure and provide a different signal than pulse pressure. For phecodes in the knowledgebase, 85% of positive correlations align with KB-status. Phenotypic patterns for Htn and Hotn overlap for several phecodes and are separate for others. Our analysis suggests five candidates for hypothesis testing research, two where the prevalence of the association with Htn or Hotn may be under appreciated, three where mechanisms that increase and decrease blood pressure may be affecting one another's expression.

CONCLUSION

PairedPheWAS methods may open a phenome-wide path to disentangling hypertension and chronic hypotension. Our classifier provides a starting point for assigning individuals to BP-categories representing the upper, lower, and middle zones of the BP spectrum. 4.7 % of individuals matching 2017 BP categories for normal, elevated BP or isolated hypertension, have diastolic pressure < 60. Research is needed to fine-tune the classifier, provide external validation, evaluate the clinical significance of diastolic pressure < 60, and test the candidate hypotheses.

Is it Time to Reappraise for Black-Box Warning on AngioJet Rheolytic Thrombectomy in Patients with Pulmonary Embolism: A Systematic Review and Meta-analysis

BACKGROUND

AngioJet rheolytic thrombectomy (ART) system has been widely used as a catheter-directed treatment (CDT) method in acute pulmonary embolism (PE), however, there has been a controversy regarding the safety of its use. In this systematic review and meta-analysis, we evaluated the efficacy and safety outcomes of ART in patients with PE.

METHODS

Our meta-analysis have been based on search in the MEDLINE, EMBASE, and Cochrane Library for studies published up to August 2022. The primary outcomes were overall pooled rates of major bleeding (MB) and minor bleeding (mB), worsening renal function (WRF), bradycardia/conduction disturbance (BCD), and PE-related and all-cause mortality in patients who underwent ART.

RESULTS

Among the 233 studies documented at initial search, 24 studies were eligible for meta-analysis, and a total of 427 PE patients who underwent ART were evaluated. Overall pooled rates of MB and mB were 9.6% (95% CI 5.9%-15.2%) and 9.2% (95% CI 6.1%-13.6%), transient BCD and WRF were 18.2% (95% CI 12.4%-26%) and 15% (95% CI 10%-21.8%), and PE-related death and all-cause death were 12.7% (95% CI 9.1%-17.3%) and 15% (95% CI 11%-20%), respectively. However, significant heterogeneity and some evidence of funnel plot asymmetry and publication bias were noted for MB, BCD and WRF, but not for PE-related death and all-cause death.

CONCLUSION

Overall pooled rates of bleeding events, BCD and WRF episodes, PE-related death and all-cause death may be considered as encouraging results for efficacy and safety issues of ART utilization in specific scenarios of acute PE, and a reappraisal for black-box warning on ART seems to be necessary.

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.

Extracorporeal Membrane Oxygenation—First Strategy for Acute Life-Threatening Pulmonary Embolism

Background

Both venoarterial extracorporeal membrane oxygenation (VA-ECMO) and percutaneous mechanical thrombectomy (PMT) are increasingly used to treat acute life-threatening pulmonary embolism (PE). However, there are little data regarding their effectiveness. This study aimed to present the short-term outcomes after managing nine patients with acute life-threatening massive or submassive PE by VA-ECMO with or without complemented PMT and propose a preliminary treatment algorithm.

Methods

This study was a single-center retrospective review of a prospectively maintained registry. It included nine consecutive patients with massive or submassive pulmonary embolism who underwent VA-ECMO for initial hemodynamic stabilization, with or without PMT, from August 2018 to November 2021.

Results

Mean patient age was 54.7 years. Four of nine patients (44.4%) required cardiopulmonary resuscitation before or during VA-ECMO cannulation. All cannulations (100%) were successfully performed percutaneously. Overall survival was 88.9% (8 of 9 patients). One patient died from a hemorrhagic stroke. Of the survivors, the median ECMO duration was 8 days in patients treated with ECMO alone and 4 days in those treated with EMCO and PMT. Five of nine patients (55.6%) required concomitant PMT to address persistent right heart dysfunction, with the remaining survivors (44.4%) receiving VA-ECMO and anticoagulation alone. For survivors receiving VA-ECMO plus PMT, median hospital lengths of stay were 7 and 13 days, respectively.

Conclusions

An ECMO-first strategy complemented with PMT can be performed effectively and safely for acute life-threatening massive or submassive PE. VA-ECMO is feasible for initial stabilization, serving as a bridge to therapy primarily in inoperable patients with massive PE. Further evaluation in a larger cohort of patients is warranted to assess whether VA-ECMO plus PMT may offer an alternative or complementary therapy to thrombolysis or surgical thrombectomy.

Type of Research

Single-center retrospective review of a prospectively maintained registry.

Percutaneous Mechanical Thrombectomy of Submassive Pulmonary Embolism and Extensive Deep Venous Thrombosis for Early Thrombus Removal

Traditional treatment with anticoagulation in nonfatal submassive pulmonary embolism can result in serious sequelae of chronic thromboembolic pulmonary hypertension or poor exercise tolerance, and functional impairment. To prevent long-term complications in previously healthy young patients, other treatment options to actively resolve existing thrombi should be considered. Despite recommendations for use in only severe clinical presentations, endovascular interventional techniques could serve as suitable treatment options for such patients. Here we report the case of a previously healthy 23-year-old female with submassive pulmonary embolism and extensive deep vein thrombosis in the inferior vena cava down to the right popliteal vein. The patient was initially treated with catheter-directed thrombolysis. However, she continued to show extensive venous thrombosis and pulmonary embolism. Percutaneous thrombectomy and aspiration using an AngioJet successfully removed the main pulmonary artery embolism and venous thrombus. The patient's recovery was uneventful, and 3-month follow-up showed no signs of recurrence or discomfort.

Treatment of acute pulmonary embolism using rheolytic thrombectomy

BACKGROUND

The AngioJet rheolytic thrombectomy (ART) system can quickly fragment and aspirate thrombi according to Bernoulli's principle.

AIMS

This retrospective study aimed to evaluate the therapeutic effects of the ART system in treating severe acute pulmonary embolism (APE), including high-risk pulmonary embolism (HR-PE) and intermediate-high-risk pulmonary embolism (IHR-PE).

METHODS

Forty-four APE patients (21 HR-PE and 23 IHR-PE) were enrolled and underwent pulmonary ART using the 6 Fr Solent Omni AngioJet device. Nineteen patients were diagnosed with APE and lower extremity deep venous thrombosis (LEDVT), and underwent thrombectomy of APE and LEDVT simultaneously using ART. All patients also received local thrombolysis with urokinase.

RESULTS

The results showed that the mean length of stay in intensive care units was 2.4±1.9 days. Significant improvements in clinical, haemodynamic and angiographic parameters were observed in both groups; the improvements in shock index, PaO2, and angiographic parameters were more obvious in the IHR-PE group. Six of the 44 patients died in hospital. During the follow-up, 35 of 38 patients were functioning well and no recurrence of APE was observed.

CONCLUSIONS

Pulmonary ART plus local thrombolysis of the pulmonary artery for HR-PE or IHR-PE is feasible and appears to be safe. Further studies are warranted to investigate comparative efficacy compared to existing treatments.

Single-session catheter-directed lysis using adjunctive power-pulse spray with AngioJet for the treatment of acute massive and submassive pulmonary embolism

OBJECTIVE

An alternative single-session catheter-directed thrombolysis (CDT) method using adjunctive power-pulse spray (PPS) technique (with the AngioJet system; Boston Scientific, Fremont, Calif) was investigated to evaluate its safety and effectiveness in the treatment of acute massive and submassive high-risk pulmonary embolism (PE).

METHODS

Between May 2016 and July 2018, patients diagnosed with extensive massive or submassive PE who triggered intensive care unit involvement and were considered for escalation of treatment were offered CDT with adjunctive PPS technique, provided they met the clinical inclusion criteria. Clinical success was defined as stabilization of hemodynamic parameters, resolution of hypoxia, and survival to discharge. In addition, reversal of right ventricular (RV) failure and pulmonary artery hypertension was evaluated after 24 to 48 hours using echocardiography. After 4 weeks, echocardiography was repeated to check for reversal of RV failure and pulmonary artery hypertension. In addition, computed tomography pulmonary angiography was performed to check for residual thrombus. Functional capacity was also re-evaluated at the follow-up consultation.

RESULTS

During the study period, 575 inpatients were diagnosed with PE at The Wollongong Hospital. Of these patients, 32 (5.6%) were referred for escalation of treatment, met the inclusion criteria, and received treatment with the CDT and PPS technique. These patients were classified as having massive (23 [71.9%]) or submassive (9 [28.1%]) PE. Technical success was achieved in all 32 patients, and 31 patients survived to discharge (96.9%). There were no major or minor adverse events and no procedure-related complications. Improvement of RV strain and pulmonary hypertension was achieved in all survivors within 48 hours of the intervention. Furthermore, all echocardiograms completed at 4 weeks after discharge were reported normal. Results from computed tomography pulmonary angiography 4 weeks after discharge demonstrated complete resolution of thrombus in 79.3% of patients, and the remaining 20.7% had only minor residual thrombus reported. In addition, 82.8% of patients reported a return to premorbid exercise tolerance by the time of postoperative consultation with the treating physician (mean follow-up, 6.7 weeks).

CONCLUSIONS

This initial series indicates that single-session CDT with adjunctive PPS technique using the AngioJet system is safe and effective in treating massive and submassive acute PE. It appears to offer several potential advantages compared with current options, allowing safer and faster thrombus resolution. Multicenter prospective trials are required to validate these findings.

[New aspects of thrombolysis and thrombectomy in pulmonary embolism]

Pulmonary embolism is a potentially life-threatening disease, which can present with varying severity. Based on an emergency risk stratification, the initial treatment strategy should be chosen without delay. While patients with a low mortality risk can be treated in an outpatient setting, patients at high risk should proceed to immediate recanalization by thrombolysis or thrombectomy. Systemic thrombolysis is the first line therapy in the absence of contraindications. The dosing (low versus full dose) and application (systemic versus local via a catheter) of alteplase, the most frequently used agent, is the subject of a number of current studies with the goal to reduce the risk of bleeding. In the case of contraindications for systemic thrombolysis surgical or alternatively, interventional thrombectomy should be performed. This article discusses these procedures in the light of the currently available literature.

Catheter-Directed Treatment of Pulmonary Embolism: A Systematic Review and Meta-Analysis of Modern Literature

We summarize the evidence for the safety and efficacy of catheter-directed thrombolysis (CDT) with and without ultrasound-assisted therapy for treating submassive and massive pulmonary embolism (PE) in a systematic review. The primary efficacy outcome was mortality. Outcomes were pooled across studies with the random-effects model. Twenty-four studies enrolled 700 patients in total; 653 received mechanical thromboembolectomy treatments for PE (mortality rate, 9% [95% confidence interval (CI), 6%-13%], P = .12; rate of minor complications, 6% [95% CI, 2%-13%]). In the ultrasound-accelerated thrombolysis (USAT) studies, the mortality rate was 4% (95% CI, 1%-11%) and in the non-USAT studies, it was 9% (95% CI, 6%-13%). Secondary safety outcomes were all bleeding events, which occurred in 12% (95% CI, 7%-20%) of the USAT studies and in 10% (95% CI, 5%-20%) of the non-USAT studies. Current clinical evidence does not prove USAT is superior over CDT methods.

Submassive pulmonary embolism

Pulmonary embolism (PE) is a common diagnosis in critical care. Depending on the severity of clot burden, the clinical picture ranges from nearly asymptomatic to cardiovascular collapse. The signs and symptoms of PE are nonspecific. The clinician must have a high index of suspicion to make the diagnosis. PE is risk stratified into 3 categories: low-risk, submassive, and massive. Submassive PE remains the most challenging with regard to initial and long-term management. Little consensus exists as to the appropriate tests for risk stratification and therapy. This article reviews the current literature and a suggested approach to these patients.

Combined thrombus aspiration and recanalization in treating Budd-Chiari syndrome with inferior vena cava thrombosis

PURPOSE

To investigate the feasibility, safety, and effectiveness of combined thrombus aspiration and inferior vena cava (IVC) recanalization for Budd-Chiari syndrome (BCS) patients with IVC thrombosis.

MATERIALS AND METHODS

From March 2011 to October 2014, 17 consecutive BCS patients with IVC thrombosis [male 13, female 4 (mean age 52.6 ± 8.4 years, range 43-72 years)] treated by combined thrombus aspiration and IVC recanalization were enrolled in this retrospective study. An 8F guiding catheter was used as the aspiration catheter. During the treatment, the aspiration catheter was placed from the right femoral vein to the IVC thrombi, and a 20-ml syringe was connected with the aspiration catheter for thrombus aspiration. IVC recanalization was performed after thrombus aspiration. Data on technical success, clinical success, and follow-up were analyzed.

RESULTS

Technical success was achieved in all patients. After thrombus aspiration, 12 patients had no visible thrombi on IVC venography, while 5 patients were shown to have the IVC mural thrombi. Afterwards, 13 patients were treated by IVC balloon dilation, and 4 patients were treated by IVC stent insertion. No patient experienced dyspnea after treatment. The average IVC pressure decreased from 29.8 ± 3.4 cmH2O to 8.6 ± 2.1 cmH2O (P < 0.001). Clinical success was achieved in all patients. The average follow-up period was 15.3 ± 11.6 months (range 2-44 months). Long-term IVC patency was achieved in 15 of 17 patients.

CONCLUSION

Combined thrombus aspiration and IVC recanalization can be a safe and effective method for BCS patients with IVC thrombosis.

Successful rescue thrombolysis in massive pulmonary embolism with intracerebral hemorrhage

We report the case of a man with a massive pulmonary embolism, which lead to cardiac arrest. After ruptured aneurysm clipping, he was successfully treated by rescue thrombolysis administered as compassionate treatment despite the risk of cerebral bleeding. The patient was discharged from the intensive care unit; his initial neurological, cardiac, and pulmonary conditions restored. In case of life-threatening pulmonary embolism, the risk-benefit ratio of thrombolysis therapy should be systematically evaluated and the decision adapted to each patient.

Successful percutaneous thrombectomy in an elderly patient with massive pulmonary embolism with cardiogenic shock

We report on an 80-year-old woman with cardiogenic shock due to massive pulmonary embolism who was successfully treated with percutaneous thrombectomy using a conventional angiographic guide wire and catheters combined with systemic thrombolysis. We successfully treated the patient without a ventilator or extracorporeal life support. We report that percutaneous thrombectomy can provide rapid improvement of hemodynamic instability and can be used as an effective adjuvant therapy for systemic thrombolysis in patients with massive pulmonary embolism. Percutaneous thrombectomy is a less invasive and reasonable alternative to surgical embolectomy for patients with massive pulmonary embolism with cardiogenic shock.

Usefulness of aspiration of pulmonary emboli and prolonged local thrombolysis to treat pulmonary embolism

Catheter-based treatment of pulmonary embolism (PE) has been demonstrated to be successful in case reports and small series. The investigators report the results of a novel, pharmacomechanical approach with prolonged infusion of urokinase in the occluded pulmonary arteries (PAs). Manual aspiration of thrombus using guide catheters was followed by introduction of thrombolysis catheters and a local bolus of urokinase. The lysis catheters were left in place, and repeat PA cine angiography and right-sided cardiac catheterization was performed 3 days later. A total of 63 patients (mean age 60 ± 15 years) were treated over 8 years: 17 patients (27%) had massive and 46 patients (73%) submassive PE. The mean PA pressure was 35 ± 10 mm Hg, and 54% had central bilateral PE. Five patients died, 1 before, 1 during, and 3 after the intervention. Nine patients (14%) had major bleeds (hemoglobin decrease >30 g/L), but in none of these patients was bleeding the reason for fatal outcome. After 3.3 ± 1.0 days, 49 of 58 living patients (84%) were restudied. In 29 (59%), there was a reduction of thrombotic burden by >90%, and in 14 (29%), the reduction was 50% to 90%. Mean PA pressure was reduced from 33 ± 8 to 21 ± 7 mm Hg (p <0.001), and this was not dependent on a reduction of thrombus. In conclusion, manual aspiration and application of prolonged thrombolysis is feasible and safe. Improvement of PA pressures is impressive and there is no correlation between morphologic disappearance of thrombus and normalization of PA pressures.