Mechanical Circulatory Support Devices in Patients with High-Risk Pulmonary Embolism

Pulmonary embolism (PE) is a common acute cardiovascular condition. Within this review, we discuss the incidence, pathophysiology, and treatment options for patients with high-risk and massive pulmonary embolisms. In particular, we focus on the role of mechanical circulatory support devices and their possible therapeutic benefits in patients who are unresponsive to standard therapeutic options. Moreover, attention is given to device selection criteria, weaning protocols, and complication mitigation strategies. Finally, we underscore the necessity for more comprehensive studies to corroborate the benefits and safety of MCS devices in PE management.

Venoarterial Extracorporeal Membrane Oxygenation With or Without Advanced Intervention for Massive Pulmonary Embolism

INTRODUCTION

Massive pulmonary embolism (MPE) is a rare but highly fatal condition. Our study's objective was to evaluate the association between advanced interventions and survival among patients with MPE treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

This is a retrospective review of the Extracorporeal Life Support Organization (ELSO) registry data. We included adult patients with MPE who were treated with VA-ECMO during 2010-2020. Our Primary outcome was survival to hospital discharge; secondary outcomes were ECMO duration among survivors and rates of ECMO-related complications. Clinical variables were compared using the Pearson chi-square and Kruskal-Wallis H tests.

RESULTS

We included 802 patients; 80 (10%) received SPE and 18 (2%) received CDT. Overall, 426 (53%) survived to discharge; survival was not significantly different among those treated with SPE or CDT on VA-ECMO (70%) versus VA-ECMO alone (52%) or SPE or CDT before VA-ECMO (52%). Multivariable regression found a trend towards increased survival among those treated with SPE or CDT while on ECMO (AOR 1.8, 95% CI 0.9-3.6), but no significant correlation. There was no association between advanced interventions and ECMO duration among survivors, or rates of ECMO-related complications.

CONCLUSION

Our study found no difference in survival in patients with MPE who received advanced interventions prior to ECMO, and a slight non-significant benefit in those who received advanced interventions while on ECMO.

Intraoperative Catastrophic Acute Pulmonary Embolism: A Case Report

This case report describes a 75-year-old female with a medical history including recurrent bowel obstruction due to sigmoid stricture, atrial fibrillation managed with rivaroxaban, a 50-year one pack-per-day smoking history, hypertension, hyperlipidemia, peripheral vascular disease with bilateral iliac stents (2015), stage III chronic kidney disease, and renal artery stenosis with bilateral stenting. She was transferred from outside hospital for an elective sigmoidectomy with ileorectal anastomosis following several recent admissions due to bowel obstruction that had been managed non-operatively. She was deemed optimized for surgery by the primary care team; however, during induction, she developed pulseless ventricular tachycardia requiring extensive resuscitative efforts. Intraoperative findings revealed biventricular failure and a clot in the right pulmonary artery. Despite aggressive treatment, including veno-arterial extracorporeal membrane oxygenation (VA ECMO), the patient's condition deteriorated, and life support was ultimately withdrawn. This case highlights the challenges of managing complex surgical patients and underscores the importance of multidisciplinary care in such cases.

Integration of Extracorporeal Membrane Oxygenation into the Management of High-Risk Pulmonary Embolism: An Overview of Current Evidence

High-risk pulmonary embolism (PE) refers to a large embolic burden causing right ventricular failure and hemodynamic instability. It accounts for approximately 5% of all cases of PE but contributes significantly to overall PE mortality. Systemic thrombolysis is the first-line revascularization therapy in high-risk PE. Surgical embolectomy or catheter-directed therapy is recommended in patients with an absolute contraindication to systemic thrombolysis. Extracorporeal membrane oxygenation (ECMO) provides respiratory and hemodynamic support for the most critically ill PE patients with refractory cardiogenic shock or cardiac arrest. The complex management of these individuals requires urgent yet coordinated multidisciplinary care. In light of existing evidence regarding the utility of ECMO in the management of high-risk PE patients, a number of possible indications for ECMO utilization have been suggested in the literature. Specifically, in patients with refractory cardiac arrest, resuscitated cardiac arrest, or refractory shock, including in cases of failed thrombolysis, venoarterial ECMO (VA-ECMO) should be considered, either as a bridge to percutaneous or surgical embolectomy or as a bridge to recovery after surgical embolectomy. We review here the current evidence on the use of ECMO as part of the management strategy for the highest-risk presentations of PE and summarize the latest data in this indication.

Complex management of pulmonary embolism in APLA syndrome: a case study of ECMO and bivalirudin utilization

We report a case of a 22-year-old female with antiphospholipid antibody (APLA) syndrome who presented with severe dyspnea. Diagnostic imaging confirmed pulmonary embolism (PE), and treatment comprised unfractionated heparin and apixaban. APLA syndrome was diagnosed based on clinical, serological, and radiological findings. During evaluation, the patient developed cardiogenic shock necessitating catheter-directed thrombolysis, followed by veno-arterial extracorporeal membrane oxygenation (VA-ECMO) due to deteriorating condition and suspected heparin-induced thrombocytopenia (HIT). Surgical embolectomy with bivalirudin use followed, and a hybrid veno-arterial-venous (VAV) ECMO setup was implemented. Postoperatively, the patient improved, transitioning to veno-venous (VV) ECMO and eventually ECMO withdrawal. ECMO is a valuable tool for managing complex cardiorespiratory cases like PE. In the context of HIT and APLA syndrome, prompt anticoagulant transition is vital, and bivalirudin is an effective heparin alternative. Our study highlights the challenges involved in managing patients needing ECMO support with immunothrombotic conditions like HIT and APLA syndrome.

Recovery and Survival of Patients After Out-of-Hospital Cardiac Arrest: A Literature Review Showcasing the Big Picture of Intensive Care Unit-Related Factors

As an important public health issue, out-of-hospital cardiac arrest (OHCA) requires several stages of high quality medical care, both on-field and after hospital admission. Post-cardiac arrest shock can lead to severe neurological injury, resulting in poor recovery outcome and increased risk of death. These characteristics make this condition one of the most important issues to deal with in post-OHCA patients hospitalized in intensive care units (ICUs). Also, the majority of initial post-resuscitation survivors have underlying coronary diseases making revascularization procedure another crucial step in early management of these patients. Besides keeping myocardial blood flow at a satisfactory level, other tissues must not be neglected as well, and maintaining mean arterial pressure within optimal range is also preferable. All these procedures can be simplified to a certain level along with using targeted temperature management methods in order to decrease metabolic demands in ICU-hospitalized post-OHCA patients. Additionally, withdrawal of life-sustaining therapy as a controversial ethical topic is under constant re-evaluation due to its possible influence on overall mortality rates in patients initially surviving OHCA. Focusing on all of these important points in process of managing ICU patients is an imperative towards better survival and complete recovery rates.

Intraoperative circulatory arrest secondary to high-risk pulmonary embolism. Case series and updated literature review

BACKGROUND

Intraoperative pulmonary embolism (PE) with cardiac arrest (CA) represents a critical and potentially fatal condition. Available treatments include systemic thrombolysis, catheter-based thrombus fragmentation or aspiration, and surgical embolectomy. However, limited studies are focused on the optimal treatment choice for this critical condition. We present a case series and an updated review of the management of intraoperative CA secondary to PE.

METHODS

A retrospective review of patients who developed high-risk intraoperative PE was performed between June 2012 and June 2022. For the updated review, a literature search on PubMed and Scopus was conducted which resulted in the inclusion of a total of 46 articles.

RESULTS

A total of 196 174 major non-cardiac surgeries were performed between 2012 and 2022. Eight cases of intraoperative CA secondary to high-risk PE were identified. We found a mortality rate of 75%. Anticoagulation therapy was administered to one patient (12.5%), while two patients (25%) underwent thrombolysis, and one case (12.5%) underwent mechanical thrombectomy combined with thrombus aspiration. Based on the literature review and our 10-year experience, we propose an algorithm for the management of intraoperative CA caused by PE.

CONCLUSION

The essential components for adequate management of intraoperative PE with CA include hemodynamic support, cardiopulmonary resuscitation, and the implementation of a primary perfusion intervention. The prompt identification of the criteria for each specific treatment modality, guided by the individual patient's characteristics, is necessary for an optimal approach.

Extracorporeal membrane oxygenation for the treatment of massive pulmonary embolism. An analysis of the ELSO database

AIM

Extracorporeal membrane oxygenation (ECMO) may be beneficial in treatment of massive pulmonary embolus (PE), however the current evidence to guide its use is limited. We aimed to compare the incidence, characteristics, treatments, and outcomes of patients with massive PE by mode of ECMO from a large international registry.

METHODS

Retrospective observational study of the Extracorporeal Life Support Organization (ELSO) database.

RESULTS

A total of 821 patients underwent 833 ECMO episodes for PE. Mean age was 49 (±15) years, 408 (50.1%) were female, and 450 (54.7%) had a cardiac arrest prior to ECMO initiation. Venoarterial (VA) ECMO was the most common mode in 489 (58.7%), followed by extracorporeal cardiopulmonary resuscitation (ECPR) in 229 (27.4%) and venovenous (VV) ECMO in 85 (10.2%). The number of episodes per year increased over the study period, predominantly driven by an increase in ECPR. In-hospital mortality was the highest for ECPR 156/229 (68.1%), followed by VA ECMO 209/498 (42.7%) and VV ECMO 24/85 (28.2%) P < 0.001. After controlling for univariate and clinically significant variables at the time of ECMO initiation, increasing age (OR 1.02 (1.00-1.03), lower pH (OR 0.18 (0.03-0.44), lower diastolic blood pressure (OR 0.99 (0.97-1.00) and ECPR mode (OR 3.67 (1.46-9.230) were independently associated with in-hospital mortality.

CONCLUSION

ECMO use for massive PE is increasing globally, and overall mortality rates compare favorably with other indications of ECMO. The use of ECPR and worsening metabolic status at initiation were associated with higher in-hospital mortality, suggesting delays in initiating ECMO should be avoided.

Cardiovascular collapse during mechanical thrombectomy for acute pulmonary embolism and the role of extracorporeal membrane oxygenation in patient rescue

BACKGROUND

Driven by the ability to avoid thrombolytics and provide a one stop procedure with immediate hemodynamic improvement, there has been a dramatic increase in the use of mechanical thrombectomy (MT) devices for the treatment of intermediate-to-high risk pulmonary embolism (PE). This study investigated the incidence and outcomes of cardiovascular collapse during MT procedures and demonstrates the role of extracorporeal membrane oxygenation (ECMO) in salvaging patients.

METHODS

This single-center retrospective review included patients with PE undergoing MT with the FlowTriever device between 2017 and 2022. Patients presenting periprocedural cardiac arrest were identified and their perioperative characteristics and postoperative outcomes were evaluated.

RESULTS

A total of 151 patients with a mean age of 64 ± 14 years who presented with intermediate-to-high risk PE received LBAT procedures during the study period. The simplified PE severity score was ≥1 in 83% of cases and the average RV/LV ratio was 1.6 ± 0.5, with and elevated troponin in 84%. Technical success was achieved in 98.7% and a significant decrease in pulmonary artery systolic pressure (PASP) was observed (37 mm Hg vs 56 mm Hg; P < .0001). Intraoperative cardiac arrest occurred in nine patients (6%). These patients were more likely to present PASP of ≥70 mm Hg (84% vs 14%; P < .001), were more hypotensive upon admission (systolic of 94 ± 14 mm Hg vs 119 ± 23 mm Hg; P = .004), presented lower oxygen saturation levels (87 ± 6% vs 92 ± 6%; P = .023) and were more likely to present with a history of recent surgery (67% vs 18%; P = .004). Four patients were rescued successfully with ECMO and their residual PE was subsequently removed before discharge by surgical embolectomy in two of the four cases and repeat MT in the other two. All five patients (3%) who did not receive ECMO support expired intraoperatively. The overall 30-day mortality was 8% with no death occurring in patients who were salvaged with ECMO.

CONCLUSIONS

Large-bore aspiration thrombectomy for acute PE is associated with favorable technical outcomes, but the concern for acute cardiac decompensation is non-negligible in patients presenting with high-risk features and a PASP of ≥70 mm Hg. ECMO can help to salvage some of these patients and should be considered in the treatment algorithms of patients deemed at high risk.

Association Between Shock Etiology and 5-Year Outcomes After Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Outcomes of patients requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO) vary greatly by etiology, but large studies that incorporate the spectrum of shock supported with ECMO are rare.

OBJECTIVES

The purpose of this study was to describe the etiology-related outcome of patients with shock supported with peripheral VA-ECMO.

METHODS

All consecutive adults with peripheral VA-ECMO between January 2015 and August 2018 at Pitié-Salpêtrière Hospital (Paris, France) were included in this retrospective observational study. The indication for VA-ECMO was cardiogenic shock. Rates of hospital death and neurological, renal, and pulmonary complications were evaluated according to etiology.

RESULTS

Among 1,253 patients, hospital and 5-year survival rates were, respectively, 73.3% and 57.3% for primary graft failure, 58.6% and 54.0% for drug overdose, 53.2% and 45.3% for dilated cardiomyopathy, 51.6% and 50.0% for arrhythmic storm, 46.8% and 38.3% for massive pulmonary embolism, 44.4% and 42.4% for sepsis-induced cardiogenic shock, 37.9% and 32.9% for fulminant myocarditis, 37.3% and 31.5% for acute myocardial infarction, 34.6% and 33.3% for postcardiotomy excluding primary graft failure, 25.7% and 22.8% for other/unknown etiology, and 11.1% and 0.0% for refractory vasoplegia shock. Renal failure requiring hemodialysis developed in 50.0%, neurological complications in 16.0%, and hydrostatic pulmonary edema in 9.0%.

CONCLUSIONS

Although the outcome differs depending on etiology, this difference is related more to the severity of the situation associated with the cause rather than the cause of the shock per se. Survival to 5 years varied by cause, which may reflect the natural course of the chronic disease and illustrates the need for long-term follow-up.

Surgical Management and Mechanical Circulatory Support in High-Risk Pulmonary Embolisms: Historical Context, Current Status, and Future Directions: A Scientific Statement From the American Heart Association

Acute pulmonary embolism is the third leading cause of cardiovascular death, with most pulmonary embolism-related mortality associated with acute right ventricular failure. Although there has recently been increased clinical attention to acute pulmonary embolism with the adoption of multidisciplinary pulmonary embolism response teams, mortality of patients with pulmonary embolism who present with hemodynamic compromise remains high when current guideline-directed therapy is followed. Because historical data and practice patterns affect current consensus treatment recommendations, surgical embolectomy has largely been relegated to patients who have contraindications to other treatments or when other treatment modalities fail. Despite a selection bias toward patients with greater illness, a growing body of literature describes the safety and efficacy of the surgical management of acute pulmonary embolism, especially in the hemodynamically compromised population. The purpose of this document is to describe modern techniques, strategies, and outcomes of surgical embolectomy and venoarterial extracorporeal membrane oxygenation and to suggest strategies to better understand the role of surgery in the management of pulmonary embolisms.

Management of High-Risk Pulmonary Embolism: What Is the Place of Extracorporeal Membrane Oxygenation?

Pulmonary embolism (PE) is a common disease with an annual incidence rate ranging from 39–115 per 100,000 inhabitants. It is one of the leading causes of cardiovascular mortality in the USA and Europe. While the clinical presentation and severity may vary, it is a life-threatening condition in its most severe form, defined as high-risk or massive PE. Therapeutic options in high-risk PE are limited. Current guidelines recommend the use of systemic thrombolytic therapy as first-line therapy (Level Ib). However, this treatment has important drawbacks including bleeding complications, limited efficacy in patients with recurrent PE or cardiac arrest, and formal contraindications. In this context, the use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in the management of high-risk PE has increased worldwide in the last decade. Strategies, including VA-ECMO as a stand-alone therapy or as a bridge to alternative reperfusion therapies, are associated with acceptable outcomes, especially if implemented before cardiac arrest. Nonetheless, the level of evidence supporting ECMO and alternative reperfusion therapies is low. The optimal management of high-risk PE patients will remain controversial until the realization of a prospective randomized trial comparing those cited strategies to systemic thrombolysis.

Imaging in Pulmonary Vascular Disease-Understanding Right Ventricle-Pulmonary Artery Coupling

The right ventricle (RV) and pulmonary arterial (PA) tree are inextricably linked, continually transferring energy back and forth in a process known as RV-PA coupling. Healthy organisms maintain this relationship in optimal balance by modulating RV contractility, pulmonary vascular resistance, and compliance to sustain RV-PA coupling through life's many physiologic challenges. Early in states of adaptation to cardiovascular disease-for example, in diastolic heart failure-RV-PA coupling is maintained via a multitude of cellular and mechanical transformations. However, with disease progression, these compensatory mechanisms fail and become maladaptive, leading to the often-fatal state of "uncoupling." Noninvasive imaging modalities, including echocardiography, magnetic resonance imaging, and computed tomography, allow us deeper insight into the state of coupling for an individual patient, providing for prognostication and potential intervention before uncoupling occurs. In this review, we discuss the physiologic foundations of RV-PA coupling, elaborate on the imaging techniques to qualify and quantify it, and correlate these fundamental principles with clinical scenarios in health and disease. © 2022 American Physiological Society. Compr Physiol 12: 1-26, 2022.

Percutaneous mechanical thrombectomy and extracorporeal membranous oxygenation: A case series

BACKGROUND

Massive or high-risk pulmonary embolism (PE) is a potentially life-threatening diagnosis with significant morbidity and mortality if treatment is delayed. Extracorporeal membrane oxygenation (ECMO) and large bore thrombectomy (LBT) in isolation have been used to stabilize and treat patients with massive PE, however, literature describing the combination of both modalities is lacking. We present a case series involving 9 patients who underwent combined ECMO and LBT and their outcomes.

METHODS

This was a retrospective chart review of patients with confirmed PE, who underwent LBT and ECMO. We retrospectively captured clinical, therapeutic, and outcome data at the time of pulmonary embolism response team (PERT) activation and during the follow-up period for up to 90 days.

RESULTS

Nine patients who had PERT activation with confirmed PE diagnosis have undergone combined LBT and ECMO initiation since the advent of our PERT program. The median age was 57 (range 28-68) years. Six patients out of 9 (55%) had cardiac arrest before therapy. All patients exhibited right heart strain on computed tomography and echocardiogram. The median ECMO duration was 5 days (range 2.3-11.6 days), with mean hospitalization of 16.1 days (range 1.5-30.9). Mortality was 22% at 90-day follow-up period.

CONCLUSION

Patients with massive pulmonary embolism who suffer cardiac arrest have significant morbidity and mortality. ECMO in combination with LBT is a viable treatment option for patients with significant hemodynamic compromise.

Clinical experiences of high-risk pulmonary thromboembolism receiving extracorporeal membrane oxygenation in single institution

Background

The main cause of death in pulmonary embolism (PE) is right-heart failure due to acute pressure overload. In this sense, extracorporeal membrane oxygenation (ECMO) might be useful in maintaining hemodynamic stability and improving organ perfusion. Some previous studies have reported ECMO as a bridge to reperfusion therapy of PE. However, little is known about the patients that benefit from ECMO.

Methods

Patients who underwent ECMO due to pulmonary thromboembolism at a single university-affiliated hospital between January 2010 and December 2018 were retrospectively reviewed.

Results

During the study period, nine patients received ECMO in high-risk PE. The median age of the patients was 60 years (range, 22–76 years), and six (66.7%) were male. All nine patients had cardiac arrests, of which three occurred outside the hospital. All the patients received mechanical support with veno-arterial ECMO, and the median ECMO duration was 1.1 days (range, 0.2–14.0 days). ECMO with anticoagulation alone was performed in six (66.7%), and ECMO with reperfusion therapy was done in three (33.3%). The 30-day mortality rate was 77.8%. The median time taken from the first cardiac arrest to initiation of ECMO was 31 minutes (range, 30–32 minutes) in survivors (n=2) and 65 minutes (range, 33–482 minutes) in non-survivors (n=7).

Conclusion

High-risk PE with cardiac arrest has a high mortality rate despite aggressive management with ECMO and reperfusion therapy. Early decision to start ECMO and its rapid initiation might help save those with cardiac arrest in high-risk PE.

Current interventional therapies in acute pulmonary embolism

Pulmonary embolism (PE) is the third leading cause of cardiovascular mortality. The management of PE is currently evolving given the development of new technologies and team-based approaches. This document will focus on risk stratification of PEs, review of the current interventional therapies, the role of clinical endpoints to assess the effectiveness of different interventional therapies, and the role for mechanical circulatory support in the complex management of this disease.

Extracorporeal membrane oxygenation in the forensic setting: A series of 19 forensic cases

Extracorporeal membrane oxygenation (ECMO) employs vascular cannulation and a gas exchange circuit to provide support to patients with severely compromised cardiopulmonary function. ECMO is often the last intervention taken before death and thus presents a unique challenge to medical examiners. This study describes the characteristics of decedents on ECMO at the time of death, including clinical indications, types of circuit configurations, causes and manners of death, gross findings at autopsy, and therapeutic complications. Files of a regional medical examiner office within an academic medical center were searched for the period between 2013 and 2019. Nineteen cases were identified with a median age of 36 years. The circumstances surrounding the initial presentation included: sudden death, trauma, substance abuse, homicide, therapeutic complication, work-related injury, drowning, and hypothermia. The underlying causes of death included injury-related, as well as respiratory and cardiac-related natural diseases. The time spent on ECMO varied from less than 1 h to 10 months. Complications encountered due to ECMO included cannulation site bleeding, pneumohemopericardium, retroperitoneal hematoma, limb ischemia, clotting, and cannula dislodgement. The patient population likely to receive ECMO has significant overlap with death circumstances likely to be reported to the medical examiner. As ECMO therapy has become increasingly available, it is of importance for medical examiners and death investigators to be familiar with the procedure as well as its limitations. Familiarity with ECMO and its sequelae allows for the proper documentation of postmortem findings and fosters an informed determination of the cause and manner of death.

SEDAR/SECCE ECMO management consensus document

ECMO is an extracorporeal cardiorespiratory support system whose use has been increased in the last decade. Respiratory failure, postcardiotomy shock, and lung or heart primary graft failure may require the use of cardiorespiratory mechanical assistance. In this scenario perioperative medical and surgical management is crucial. Despite the evolution of technology in the area of extracorporeal support, morbidity and mortality of these patients continues to be high, and therefore the indication as well as the ECMO removal should be established within a multidisciplinary team with expertise in the area. This consensus document aims to unify medical knowledge and provides recommendations based on both the recent bibliography and the main national ECMO implantation centres experience with the goal of improving comprehensive patient care.

Catheter Directed Interventions for pulmonary embolism: Institutional Trends over a Decade 2010-2019

OBJECTIVES

Catheter Directed Interventions (CDIs) are commonly performed for acute Pulmonary Embolism (PE). The evolving catheter types and treatment algorithms impact the utilization and outcomes of these interventions. This study aimed to investigate the changes in CDI practice and their impact on outcomes.

METHODS

Patients who underwent CDIs for PE between 2010 and 2019 at a single institution were identified from a prospectively maintained database. A PE team was launched in 2012, and in 2014 was established as an official Pulmonary Embolism Response Team (PERT). CDI annual usage trends and clinical failures were recorded. Clinical success was defined as physiologic improvement in the absence of major bleeding, perioperative stroke or other procedure-related adverse event, decompensation for sub-massive or persistent shock for massive PE, need for surgical thromboembolectomy or death. Major bleeding was defined as requiring a blood transfusion, a surgical intervention, or suffering from an intracranial hemorrhage.

RESULTS

372 patients received a CDI for acute PE during the study period: age 58.9±15.4 years, males 187 (50.3%), sub-massive PE 340 (91.4%). CDI showed a steep increase in the early PERT years, peaking in 2016 with a subsequent decline. Ultrasound-assisted thrombolysis was the predominant CDI technique peaking at 84% of all CDI in 2014. Suction thrombectomy utilization peaked at 15.2% of CDI in 2019. Mean alteplase dose with catheter thrombolysis techniques decreased from 26.8±12.5mg in 2013 to 13.9±7.5mg in 2019 (P<.001). Mean lysis time decreased from 17.2±8.3 hours in 2013 to 11.3±8.2 hours in 2019 (P<.001). Clinical success for the massive and the submassive PE cohorts was 58.1% and 91.2% respectively; the major bleed rate was 25.0% and 5.3%. There were two major clinical success peaks, one in 2015 mirroring our technical learning curve and one in 2019 mirroring our patient selection learning curve. The clinical success drop in 2018 was primarily derived from blood transfusions due to acute blood loss during suction thrombectomy.

CONCLUSIONS

CDIs for acute PE have rapidly evolved with high success rates. Multidisciplinary approaches amongst centers with appropriate expertise are advisable for the safe and successful implementation of catheter interventions.

Can VA-ECMO Be Used as an Adequate Treatment in Massive Pulmonary Embolism?

Introduction: Massive acute pulmonary embolism (MAPE) with obstructive cardiogenic shock is associated with a mortality rate of more than 50%. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been increasingly used in refractory cardiogenic shock with very good results. In MAPE, although it is currently recommended as part of initial resuscitation, it is not yet considered a stand-alone therapy. Material and Methods: All patients with MAPE requiring the establishment of VA-ECMO and admitted to our tertiary intensive care unit were analysed over a period of 10 years. The characteristics of these patients, before, during and after ECMO were extracted and analysed. Results: A total of 36 patients were included in the present retrospective study. Overall survival was 64%. In the majority of cases, the haemodynamic and respiratory status of the patient improved significantly within the first 24 h on ECMO. The 30-day survival significantly increased when ECMO was used as stand-alone therapy (odds ratio (OR) 15.58, 95% confidence interval (CI) 2.65–91.57, p = 0.002). Nevertheless, when ECMO was implanted following the failure of thrombolysis, the bleeding complications were major (17 (100%) vs. 1 (5.3%) patients, p < 0.001) and the 30-day mortality increased significantly (OR 0.11, 95% CI 0.022–0.520, p = 0.006). Conclusions: The present retrospective study is certainly one of the most important in terms of the number of patients with MAPE and shock treated with VA-ECMO. This short-term mechanical circulatory support, used as a stand-alone therapy in MAPE, allows for the optimal stabilisation of patients.

Management of perioperative acute massive pulmonary embolism: A case series

The management of acute massive pulmonary embolism during the perioperative period is challenging. Accurate diagnosis using echocardiography and application of rapid extracorporeal membrane oxygenation can improve patients' outcomes.

Venoarterial Extracorporeal Membrane Oxygenation in Massive Pulmonary Embolism-Related Cardiac Arrest: A Systematic Review

OBJECTIVE

Management of patients experiencing massive pulmonary embolism-related cardiac arrest is controversial. Venoarterial extracorporeal membranous oxygenation has emerged as a potential therapeutic option for these patients. We performed a systematic review assessing survival and predictors of mortality in patients with massive PE-related cardiac arrest with venoarterial extracorporeal membranous oxygenation use.

DATA SOURCES

A literature search was started on February 16, 2020, and completed on March 16, 2020, using PubMed, Embase, Cochrane Central, Cinahl, and Web of Science.

STUDY SELECTION

We included all available literature that reported survival to discharge in patients managed with venoarterial extracorporeal membranous oxygenation for massive PE-related cardiac arrest.

DATA EXTRACTION

We extracted patient characteristics, treatment details, and outcomes.

DATA SYNTHESIS

About 301 patients were included in our systemic review from 77 selected articles (total screened, n = 1,115). About 183 out of 301 patients (61%) survived to discharge. Patients (n = 51) who received systemic thrombolysis prior to cannulation had similar survival compared with patients who did not (67% vs 61%, respectively; p = 0.48). There was no significant difference in risk of death if PE was the primary reason for admission or not (odds ratio, 1.62; p = 0.35) and if extracorporeal membranous oxygenation cannulation occurred in the emergency department versus other hospital locations (odds ratio, 2.52; p = 0.16). About 53 of 60 patients (88%) were neurologically intact at discharge or follow-up. Multivariate analysis demonstrated three-fold increase in the risk of death for patients greater than 65 years old (adjusted odds ratio, 3.08; p = 0.03) and six-fold increase if cannulation occurred during cardiopulmonary resuscitation (adjusted odds ratio, 5.67; p = 0.03).

CONCLUSIONS

Venoarterial extracorporeal membranous oxygenation has an emerging role in the management of massive PE-related cardiac arrest with 61% survival. Systemic thrombolysis preceding venoarterial extracorporeal membranous oxygenation did not confer a statistically significant increase in risk of death, yet age greater than 65 and cannulation during cardiopulmonary resuscitation were associated with a three- and six-fold risks of death, respectively.

ECMO in Cardiac Arrest: A Narrative Review of the Literature

Cardiac arrest (CA) is a frequent cause of death and a major public health issue. To date, conventional cardiopulmonary resuscitation (CPR) is the only efficient method of resuscitation available that positively impacts prognosis. Extracorporeal membrane oxygenation (ECMO) is a complex and costly technique that requires technical expertise. It is not considered standard of care in all hospitals and should be applied only in high-volume facilities. ECMO combined with CPR is known as ECPR (extracorporeal cardiopulmonary resuscitation) and permits hemodynamic and respiratory stabilization of patients with CA refractory to conventional CPR. This technique allows the parallel treatment of the underlying etiology of CA while maintaining organ perfusion. However, current evidence does not support the routine use of ECPR in all patients with refractory CA. Therefore, an appropriate selection of patients who may benefit from this procedure is key. Reducing the duration of low blood flow by means of performing high-quality CPR and promoting access to ECPR, may improve the survival rate of the patients presenting with refractory CA. Indeed, patients who benefit from ECPR seem to carry better neurological outcomes. The aim of this present narrative review is to present the most recent literature available on ECPR and to clarify its potential therapeutic role, as well as to provide an in-depth explanation of equipment and its set up, the patient selection process, and the patient management post-ECPR.

Fibrinolytics for the treatment of pulmonary embolism

The use of fibrinolytic agents in acute pulmonary embolism (PE), first described over 50 years ago, hastens the resolution of RV stain, leading to earlier hemodynamic improvement. However, this benefit comes at the increased risk of bleeding. The strongest indication for fibrinolysis is in high-risk PE, or that characterized by sustained hypotension, while its use in patients with intermediate-risk PE remains controversial. Fibrinolysis is generally not recommended for routine use in intermediate-risk PE, although most guidelines advise that it may be considered in patients with signs of acute decompensation and an overall low bleeding risk. The efficacy of fibrinolysis often varies significantly between patients, which may be at least partially explained by several factors found to promote resistance to fibrinolysis. Ultimately, treatment decisions should carefully weigh the risks and benefits of the individual clinical scenario at hand, including the overall severity, the patient's bleeding risk, and the presence of factors known to promote resistance to fibrinolysis. This review aims to further explore the use of fibrinolytic agents in the treatment of PE including specific indications, outcomes, and special considerations.

Mid-term outcomes with the use of extracorporeal membrane oxygenation for cardiopulmonary failure secondary to massive pulmonary embolism

OBJECTIVES

There has been increasing interest in using extracorporeal membrane oxygenation (ECMO) to rescue patients with pulmonary embolism (PE) in the advanced stages of respiratory or haemodynamic decompensation. We examined mid-term outcomes and risk factors for in-hospital mortality.

METHODS

We conducted a retrospective study of 36 patients who required ECMO placement (32 veno-arterial ECMO, 4 veno-venous) following acute PE. Survival curves were estimated using the Kaplan-Meier method. Risk factors for in-hospital mortality were assessed by logistic regression analysis. Functional status and quality of life were assessed by phone questionnaire.

RESULTS

Overall survival to hospital discharge was 44.4% (16/36). Two-year survival conditional to discharge was 94% (15/16). Two-year survival after veno-arterial ECMO was 39% (13/32). In patients supported with veno-venous ECMO, survival to discharge was 50%, and both patients were alive at follow-up. In univariable analysis, a history of recent surgery (P = 0.064), low left ventricular ejection fraction (P = 0.029), right ventricular dysfunction ≥ moderate at weaning (P = 0.083), on-going cardiopulmonary resuscitation at ECMO placement (P = 0.053) and elevated lactate at weaning (P = 0.002) were risk factors for in-hospital mortality. In multivariable analysis, recent surgery (P = 0.018) and low left ventricular ejection fraction at weaning (P = 0.013) were independent factors associated with in-hospital mortality. At a median follow-up of 23 months, 10 patients responded to our phone survey; all had acceptable functional status and quality of life.

CONCLUSIONS

Massive acute PE requiring ECMO support is associated with high early mortality, but patients surviving to hospital discharge have excellent mid-term outcomes with acceptable functional status and quality of life. ECMO can provide a stable platform to administer other intervention with the potential to improve outcomes. Risk factors for in-hospital mortality after PE and veno-arterial ECMO support were identified.

Management of Acute Pulmonary Embolism

Purpose of the Review

Over 100,000 cardiovascular-related deaths annually are caused by acute pulmonary embolism (PE). While anticoagulation has historically been the foundation for treatment of PE, this review highlights the recent rapid expansion in the interventional strategies for this condition.

Recent Findings

At the time of diagnosis, appropriate risk stratification helps to accurately identify patients who may be candidates for advanced therapeutic interventions. While systemic thrombolytics (ST) is the mostly commonly utilized intervention for high-risk PE, the risk profile of ST for intermediate-risk PE limits its use. Assessment of an individualized patient risk profile, often via a multidisciplinary pulmonary response team (PERT) model, there are various interventional strategies to consider for PE management. Novel therapeutic options include catheter-directed thrombolysis, catheter-based embolectomy, or mechanical circulatory support for certain high-risk PE patients. Current data has established safety and efficacy for catheter-based treatment of PE based on surrogate outcome measures. However, there is limited long-term data or prospective comparisons between treatment modalities and ST. While PE diagnosis has improved with modern cross-sectional imaging, there is interest in improved diagnostic models for PE that incorporate artificial intelligence and machine learning techniques.

Summary

In patients with acute pulmonary embolism, after appropriate risk stratification, some intermediate and high-risk patients should be considered for interventional-based treatment for PE.

Massive pulmonary embolism with intra-hospital cardiac arrest and full recovery of right ventricular function after veno-arterial extracorporeal membrane oxygenation therapy: a case report

Background

Massive pulmonary embolism (PE) with shock constitutes a life-threatening disease, challenging physicians with the need for fast decision-making in an emergency situation. While thrombolytic treatment or thrombectomy are considered the treatment of choice in high-risk PE, these strategies might not be able to unload the right ventricle (RV) fast enough in some patients with severe cardiogenic shock.

Case summary

We present a case of a patient with massive bilateral central PE who presented in cardiogenic shock, rapidly deteriorating to cardiac arrest. After successful re-establishing spontaneous circulation, the patient remained highly unstable, necessitating a treatment strategy ensuring a quick stabilization of the circulation. Therefore, we decided to use veno-arterial extracorporeal membrane oxygenation (vaECMO) as a supportive strategy allowing for autolysis of the lung to dissolve the thrombi (bridge to recovery). We were able to wean the patient from vaECMO support within 4 days and documented a complete recovery of right ventricular in echocardiography before hospital discharge.

Discussion

The concept of vaECMO treatment alone might be a valuable alternative in selected patients with massive PE and cardiogenic shock, in whom thrombolytic therapy might not unload the RV fast enough.

Efficacy and safety of extracorporeal membrane oxygenation for high-risk pulmonary embolism: A systematic review and meta-analysis

High-risk pulmonary embolism (PE) requires hemodynamic and respiratory support along with reperfusion strategies. Recently updated European guidelines assign a low class of recommendation to extracorporeal membrane oxygenation (ECMO) for high-risk PE. This systematic review assessed clinical outcomes after ECMO in high-risk PE. We searched electronic databases including PubMed, Embase and Web of Science from January 2000 to April 2020. Efficacy outcomes included in-hospital survival with good neurological outcome and survival at follow-up. Safety outcomes included lower limb ischemia and hemorrhagic and ischemic stroke. Where possible (absence of high heterogeneity), meta-analyses of outcomes were undertaken using a random-effects model. We included 16 uncontrolled case-series (533 participants). In-hospital survival with good neurological outcome ranged between 50% and 95% while overall survival at follow-up ranged from 35% to 95%, both with a major degree of heterogeneity (I² > 70%). The prevalence of lower limb ischemia was 8% (95% CI 3% to 15%). The prevalence of stroke (either hemorrhagic or ischemic) was 11% (95% CI 3% to 23%), with notable heterogeneity (I² = 63.35%). Based on currently available literature, it is not possible to draw definite conclusions on the usefulness of ECMO for high-risk PE. Prospective, multicenter, large-scale studies or nationwide registries are needed to best define the role of ECMO for high-risk PE. PROSPERO registration ID: CRD42019136282.

Current Controversies in Caring for the Critically Ill Pulmonary Embolism Patient

Emergency physicians must be prepared to rapidly diagnose and resuscitate patients with pulmonary embolism (PE). Certain aspects of PE resuscitation run counter to typical approaches. A specific understanding of the pathophysiology of PE is required to avoid cardiovascular collapse potentially associated with excessive intravenous fluids and positive pressure ventilation. Once PE is diagnosed, rapid risk stratification should be performed and treatment guided by patient risk class. Although anticoagulation remains the mainstay of PE treatment, emergency physicians also must understand the indications and contraindications for thrombolysis and should be aware of new therapies and models of care that may improve outcomes.

Venoarterial extracorporeal membrane oxygenation is an effective management strategy for massive pulmonary embolism patients

OBJECTIVE

Treatment of massive pulmonary embolism (MPE) is controversial, with mortality rates ranging from 25% to 65%. Patients commonly present with profound shock or cardiac arrest. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used as a form of acute cardiopulmonary support in critically ill patients. We reviewed our institution's pulmonary embolism response team experience using VA-ECMO for patients presenting with advanced shock and/or cardiac arrest from MPE.

METHODS

From March 2017 to July 2019 we retrospectively reviewed 17 consecutive patients at our institution with MPE who were placed on VA-ECMO for initial hemodynamic stabilization.

RESULTS

The mean patient age and body mass index was 55.8 years and 31.8, respectively. Ten of 17 patients (59%) required cardiopulmonary resuscitation before or during VA-ECMO cannulation. All patients had evidence of profound shock with a mean initial lactate of 8.95 mmol/L, a mean pH of 7.10, and a mean serum creatinine of 1.78 mg/dL. Seventeen of 17 cannulations (100%) were performed percutaneously, with 41% (n = 7) of patients placed on VA-ECMO while awake and using local analgesia. Five of 17 patients (29%) required reperfusion cannulas, with 0% incidence of limb loss. Overall survival was 13 of 17 patients (76%), with causes of death resulting from anoxic brain injury (n = 2), septic shock (n = 1), and cardiopulmonary resuscitation-induced hemorrhage from liver laceration (n = 1). In survivors, 12 of 13 patients (92%) were discharged without evidence of neurologic insult. The median duration of the VA-ECMO run for survivors was 86 hours (range, 45-218 hours). In survivors, the median length of time from ECMO cannulation to lactate clearance (<2.0 mmol/L) was 10 hours and the median length of time from ECMO cannulation to freedom from vasopressors was 6 hours. Three of 13 patients (23%) required concomitant percutaneous thrombectomy and catheter-directed thrombolysis to address persistent right heart dysfunction, with the remaining survivors (77%) receiving VA-ECMO and anticoagulation alone as definitive therapy for their MPE. The median intensive care and hospital length of stay for survivors was 9 and 13 days, respectively.

CONCLUSIONS

VA-ECMO was effective at salvaging highly unstable patients with MPE. Survivors had rapid reversal of multiple organ failure with ECMO as their primary therapy. The majority of survivors required ECMO and anticoagulation alone for definitive therapy of their MPE.

ARDS and Massive Pulmonary Embolism: The Combined Use of Extracorporeal Membrane Oxygenation (ECMO) with Thrombolytics

Pancreatitis causes a systemic inflammatory response that can lead to acute respiratory distress syndrome (ARDS). We present a case of severe ARDS complicated by a pulmonary embolism (PE) in a 39-year-old female that developed rapidly progressive pancreatitis secondary to hypertriglyceridemia.

Supportive Therapy: Extracorporeal Membrane Oxygenation

Acute high-risk pulmonary embolism (PE) is characterized by life-threatening hemodynamic instability that may lead to refractory cardiac arrest. Recently, extracorporeal membrane oxygenation (ECMO) has been used to provide primary cardiopulmonary support for select high-risk PE patients or before surgical embolectomy. This article reviews the growing body of literature regarding ECMO support of acute high-risk PE.

Massive pulmonary embolism: embolectomy or extracorporeal membrane oxygenation?

PURPOSE OF REVIEW

To highlight updates on the use of extracorporeal membrane oxygenation (ECMO) and surgical embolectomy in the treatment of massive pulmonary embolism.

RECENT FINDINGS

Outcomes for surgical embolectomy for massive pulmonary embolism have improved in the recent past. More contemporary therapeutic options include catheter embolectomy, which although offer less invasive means of treating this condition, need further study. The use of ECMO as either a bridge or mainstay of treatment in patients with contraindications to fibrinolysis and surgical embolectomy, or have failed initial fibrinolysis, has increased, with data suggesting improved outcomes with earlier implementation in selected patients.

SUMMARY

Although surgical embolectomy continues to be the initial treatment of choice in massive pulmonary embolism with contraindications or failed fibrinolysis, the use of ECMO in these high-risk patients provides an important tool in managing this often fatal condition.

In-Hospital Outcome in Patients Underwent Extracorporeal Membrane Oxygenation in Life-Threatening High-Risk Pulmonary Embolism

Background and Objectives

Acute pulmonary embolism(PE) has high mortality and morbidity. Although reperfusion therapies can be used in high-risk PE patients, a few patients remain in a highly hemodynamically unstable state. In these patients, extracorporeal membrane oxygenation (ECMO) can be used to restore tissue oxygenation and improve their hemodynamic status. We retrospectively assessed the outcomes of ECMO in patients with high-risk PE.

Methods

We retrospectively screened all acute PE patients from January 2010 to December 2019 in 5 university hospitals in Korea. We reviewed their medical records and clinical outcomes.

Results

During the study period, we screened total 3,572 patients with PE and found 33 high-risk PE patients with ECMO (17 women, 58.3±14.7 years old) whose data were analyzed. Common causes of acute PE included limited mobility (8, 24.2%), a recent operation (6, 18.2%) and a recent hospitalization for medical diseases (3, 9.1%). Among the patients, 25 (75.0%) had a history of cardiopulmonary resuscitation. Nineteen patients had received primary therapy (intravenous thrombolysis in 10, thrombectomy in 8 and catheter-based thrombolysis in 1). The mean duration of ECMO was 5.0 days (range, 1–23 days). The in-hospital mortality rate was 51.5%. Twenty-two patients (66.7%) had ECMO related complications (15 [46.9%] had bleeding, 10 [31.3%] had an infection, and 5 [15.6%] had vascular complications). Of 15 cases with bleeding, 13 of them had mild bleeding associated with catheter insertion, and 2 had moderate multiorgan bleeding.

Conclusions

ECMO can be used as an additional or alternative circulatory support method in high-risk PE patients. However, physicians should keep in mind a high incidence of complications related to ECMO.

Immediate and late impact of reperfusion therapies in acute pulmonary embolism

Haemodynamic instability and right ventricular dysfunction are the key determinants of short-term prognosis in patients with acute pulmonary embolism (PE). Residual thrombi and persistent right ventricular dysfunction may contribute to post-PE functional impairment, and influence the risk of developing chronic thromboembolic pulmonary hypertension. Patients with haemodynamic instability at presentation (high-risk PE) require immediate primary reperfusion to relieve the obstruction in the pulmonary circulation and increase the chances of survival. Surgical removal of the thrombi or catheter-directed reperfusion strategies is alternatives in patients with contraindications to systemic thrombolysis. For haemodynamically stable patients with signs of right ventricular overload or dysfunction (intermediate-risk PE), systemic standard-dose thrombolysis is currently not recommended, because the risk of major bleeding associated with the treatment outweighs its benefits. In such cases, thrombolysis should be considered only as a rescue intervention if haemodynamic decompensation develops. Catheter-directed pharmaco-logical and pharmaco-mechanical techniques ensure swift recovery of echocardiographic and haemodynamic parameters and may be characterized by better safety profile than systemic thrombolysis. For survivors of acute PE, little is known on the effects of reperfusion therapies on the risk of chronic functional and haemodynamic impairment. In intermediate-risk PE patients, available data suggest that systemic thrombolysis may have little impact on long-term symptoms and functional limitation, echocardiographic parameters, and occurrence of chronic thromboembolic pulmonary hypertension. Ongoing and future interventional studies will clarify whether ‘safer’ reperfusion strategies may improve early clinical outcomes without increasing the risk of bleeding and contribute to reducing the burden of long-term complications after intermediate-risk PE.

Pulmonary embolism response teams: Purpose, evidence for efficacy, and future research directions

Pulmonary embolism (PE) is a major cause of morbidity and mortality in the United States. Although new therapeutic tools and strategies have recently been developed for the diagnosis and treatment of patients with PE, the outcomes for patients who present with massive or high-risk PE remain dismal. To address this crisis, pulmonary embolism response teams (PERTs) are being created around the world in an effort to immediately and simultaneously engage multiple specialists to determine the best course of action and coordinate the clinical care for patients with acute PE. The scope of this review is to describe the PERT model and purpose, present the structure and organization, examine the available evidence for efficacy and usefulness, and propose future directions for research that is needed to demonstrate the value of PERT and determine if this multidisciplinary approach represents a new standard of care.

Extracorporeal membrane oxygenation in life-threatening massive pulmonary embolism

Introduction:

In massive pulmonary embolism (PE) with circulatory collapse or with cardiac arrest, treatment can be difficult. Often, the diagnosis is unclear, and the time to treatment is crucial. Our institution has had an out-of-hospital team intended for the treatment of accidental hypothermia with extra corporeal membrane oxygenation (ECMO) since 2004. The team has occasionally been involved in patients suffering massive PE.

Methods:

We were called to 38 patients with PE, but two were assessed as untreatable. Seventeen were treated with cardiopulmonary resuscitation followed by veno-arterial ECMO. Nineteen were prepared for ECMO with sheaths in the femoral vessels and were intensively observed during diagnosis and treatment. Five of these patients later progressed to ECMO due to cardiac arrest during treatment with thrombolytic medication. Most of the patients were treated with heparin and thrombolytic medication, but if the medications were contraindicated, they were treated with either surgical thrombectomy or only with heparin awaiting spontaneous thrombolysis.

Results:

Of the 36 patients we intended to treat, 25 (69%) survived one month and 20 survived one year (56%). Of the 22 patients treated with ECMO, 11 survived one month (50%) and 10 survived one year (45%).

Discussion:

The treatment could have been more uniform. It seems reasonable to build up a PE alert team with ECMO capability to take care of patients with massive PE.

Conclusion:

The treatment of thrombolytic medications in massive PE is risky, but if the patient is treated or prepared for ECMO, it can be lifesaving.