Catheter-based therapy for high-risk or intermediate-risk pulmonary embolism: death and re-hospitalization.

BACKGROUND AND AIMS: Catheter-based therapies (CBTs) have been developed as a treatment option in patients with pulmonary embolism (PE). There remains a paucity of data to inform decision-making in patients with intermediate-risk or high-risk PE. The aim of this study was to characterize in-hospital and readmission outcomes in patients with intermediate-risk or high-risk PE treated with vs. without CBT in a large retrospective registry. METHODS: Patients hospitalized with intermediate-risk or high-risk PE were identified using the 2017-20 National Readmission Database. In-hospital outcomes included death and bleeding and 30- and 90-day readmission outcomes including all-cause, venous thromboembolism (VTE)-related and bleeding-related readmissions. Inverse probability of treatment weighting (IPTW) was utilized to compare outcomes between CBT and no CBT. RESULTS: A total of 14 903 [2076 (13.9%) with CBT] and 42 829 [8824 (20.6%) with CBT] patients with high-risk and intermediate-risk PE were included, respectively. Prior to IPTW, patients with CBT were younger and less likely to have cancer and cardiac arrest, receive systemic thrombolysis, or be on mechanical ventilation. In the IPTW logistic regression model, CBT was associated with lower odds of in-hospital death in high-risk [odds ratio (OR) 0.83, 95% confidence interval (CI) 0.80-0.87] and intermediate-risk PE (OR 0.76, 95% CI 0.70-0.83). Patients with high-risk PE treated with CBT were associated with lower risk of 90-day all-cause [hazard ratio (HR) 0.77, 95% CI 0.71-0.83] and VTE (HR 0.46, 95% CI 0.34-0.63) readmission. Patients with intermediate-risk PE treated with CBT were associated with lower risk of 90-day all-cause (HR 0.75, 95% CI 0.72-0.79) and VTE (HR 0.66, 95% CI 0.57-0.76) readmission. CONCLUSIONS: Among patients with high-risk or intermediate-risk PE, CBT was associated with lower in-hospital death and 90-day readmission. Prospective, randomized trials are needed to confirm these findings.

Contemporary Management and Outcomes of Patients With High-Risk Pulmonary Embolism.

BACKGROUND: Contemporary care patterns/outcomes in high-risk pulmonary embolism (PE) patients are unknown. OBJECTIVES: This study sought to characterize the management of high-risk PE patients and identify factors associated with poor outcomes. METHODS: A retrospective analysis of the PERT (Pulmonary Embolism Response Team) Consortium Registry was performed. Patients presenting with intermediate-risk PE, high-risk PE, and catastrophic PE (those with hemodynamic collapse) were identified. Patient characteristics were compared with chi-square testing for categorical covariates and Student's t-test for continuous covariates. Multivariable logistic regression was used to assess associations between clinical characteristics and outcomes in the high-risk population. RESULTS: Of 5,790 registry patients, 2,976 presented with intermediate-risk PE and 1,442 with high-risk PE. High-risk PE patients were more frequently treated with advanced therapies than intermediate-risk PE patients (41.9% vs 30.2%; P < 0.001). In-hospital mortality (20.6% vs 3.7%; P < 0.001) and major bleeding (10.5% vs. 3.5%; P < 0.001) were more common in high-risk PE. Multivariable regression analysis demonstrated vasopressor use (OR: 4.56; 95% CI: 3.27-6.38; P < 0.01), extracorporeal membrane oxygenation use (OR: 2.86; 95% CI: 1.12-7.30; P = 0.03), identified clot-in-transit (OR: 2.26; 95% CI: 1.13-4.52; P = 0.02), and malignancy (OR: = 1.70; 95% CI: 1.13-2.56; P = 0.01) as factors associated with in-hospital mortality. Catastrophic PE patients (n = 197 [13.7% of high-risk PE patients]) had higher in-hospital mortality (42.1% vs 17.2%; P < 0.001) than those presenting with noncatastrophic high-risk PE. Extracorporeal membrane oxygenation (13.3% vs. 4.8% P < 0.001) and systemic thrombolysis (25% vs 11.3%; P < 0.001) were used more commonly in catastrophic PE. CONCLUSIONS: In the largest analysis of high-risk PE patients to date, mortality rates were high with the worst outcomes among patients with hemodynamic collapse.

Outcomes in High-Risk Pulmonary Embolism Patients Undergoing FlowTriever Mechanical Thrombectomy or Other Contemporary Therapies: Results From the FLAME Study.

BACKGROUND: Hemodynamically unstable high-risk, or massive, pulmonary embolism (PE) has a reported in-hospital mortality of over 25%. Systemic thrombolysis is the guideline-recommended treatment despite limited evidence. The FLAME study (FlowTriever for Acute Massive PE) was designed to generate evidence for interventional treatments in high-risk PE. METHODS: The FLAME study was a prospective, multicenter, nonrandomized, parallel group, observational study of high-risk PE. Eligible patients were treated with FlowTriever mechanical thrombectomy (FlowTriever Arm) or with other contemporary therapies (Context Arm). The primary end point was an in-hospital composite of all-cause mortality, bailout to an alternate thrombus removal strategy, clinical deterioration, and major bleeding. This was compared in the FlowTriever Arm to a prespecified performance goal derived from a contemporary systematic review and meta-analysis. RESULTS: A total of 53 patients were enrolled in the FlowTriever Arm and 61 in the Context Arm. Context Arm patients were primarily treated with systemic thrombolysis (68.9%) or anticoagulation alone (23.0%). The primary end point was reached in 9/53 (17.0%) FlowTriever Arm patients, significantly lower than the 32.0% performance goal (P<0.01). The primary end point was reached in 39/61 (63.9%) Context Arm patients. In-hospital mortality occurred in 1/53 (1.9%) patients in the FlowTriever Arm and in 18/61 (29.5%) patients in the Context Arm. CONCLUSIONS: Among patients selected for mechanical thrombectomy with the FlowTriever System, a significantly lower associated rate of in-hospital adverse clinical outcomes was observed compared with a prespecified performance goal, primarily driven by low all-cause mortality of 1.9%. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04795167.

Prevalence and Predictors of Cardiogenic Shock in Intermediate-Risk Pulmonary Embolism: Insights From the FLASH Registry.

BACKGROUND: Patients with acute pulmonary embolism (PE) and hypotension (high-risk PE) have high mortality. Cardiogenic shock can also occur in nonhypotensive or normotensive patients (intermediate-risk PE) but is less well characterized. OBJECTIVES: The authors sought to evaluate the prevalence and predictors of normotensive shock in intermediate-risk PE. METHODS: Intermediate-risk PE patients in the FLASH (FlowTriever All-Comer Registry for Patient Safety and Hemodynamics) registry undergoing mechanical thrombectomy with the FlowTriever System (Inari Medical) were included. The prevalence of normotensive shock (systolic blood pressure ≥90 mm Hg but cardiac index ≤2.2 L/min/m2) was assessed. A composite shock score consisting of markers of right ventricular function and ischemia (elevated troponin, elevated B-type natriuretic peptide, moderately/severely reduced right ventricular function), central thrombus burden (saddle PE), potential additional embolization (concomitant deep vein thrombosis), and cardiovascular compensation (tachycardia) was prespecified and assessed for its ability to identify normotensive shock patients. RESULTS: Over one-third of intermediate-risk PE patients in FLASH (131/384, 34.1%) were in normotensive shock. The normotensive shock prevalence was 0% in patients with a composite shock score of 0 and 58.3% in those with a score of 6 (highest score). A score of 6 was a significant predictor of normotensive shock (odds ratio: 5.84; 95% CI: 2.00-17.04). Patients showed significant on-table improvements in hemodynamics post-thrombectomy, including normalization of the cardiac index in 30.5% of normotensive shock patients. Right ventricular size, function, dyspnea, and quality of life significantly improved at the 30-day follow-up. CONCLUSIONS: Although hemodynamically stable, over one-third of intermediate-risk FLASH patients were in normotensive shock with a depressed cardiac index. A composite shock score effectively further risk stratified these patients. Mechanical thrombectomy improved hemodynamics and functional outcomes at the 30-day follow-up.

Mechanical thrombectomy versus catheter directed thrombolysis in patients with pulmonary embolism: A multicenter experience.

OBJECTIVES: Compare in-hospital outcomes of patients treated with either mechanical thrombectomy (MT) or catheter directed lysis (CDL) in treatment of acute pulmonary embolism (PE). METHODS: This is a multicenter, retrospective cohort study of patients undergoing MT or CDL for acute PE between 2014 and 2021. The primary outcome was the composite of in-hospital death, significant bleed, vascular complication, or need for mechanical support post-procedure. Secondary outcomes included the individual components of the composite outcome in addition to blood transfusions, invasive hemodynamics, echocardiographic data, and intensive care unit (ICU) utilization. RESULTS: 458 patients were treated for PE with 266 patients in the CDL arm and 192 patients in the MT arm. The primary composite endpoint was not significantly different between the two groups with CDL 12% versus MT 11% (p = 0.5). There was a significant difference in total length of ICU time required with more in the CDL group versus MT (3.8 ± 2.0 vs. 2.8 ± 3.0 days, p = 0.009). All other secondary end points showed no significant difference between the groups. CONCLUSIONS: In patients undergoing catheter directed treatment of PE, there was no difference between MT and CDL in terms of in-hospital mortality, bleeds, catheter-related complications, and hemodynamics.

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.

Comprehensive Monitoring in Patients With Dual Lumen Right Atrium to Pulmonary Artery Right Ventricular Assist Device.

Right ventricular assist devices (RVADs) can be used in patients with acute right heart failure. A novel device that has recently been deployed is the right atrium to pulmonary artery (RA-PA) dual lumen single cannula (DLSC). One of the limitations is that it occupies a large proportion of the right ventricular outflow tract and PA; therefore, standard continuous hemodynamic monitoring with a pulmonary artery catheter is commonly not used. Serial echocardiography is pivotal for device deployment, monitoring device position, assessing RV readiness for decannulation, and surveilling for short-term complications. We performed a retrospective case series of 24 patients with RA-PA DLSC RVAD assessing echocardiographic RV progression and vasoactive infusion requirements. The overall survival was 66.6%. The average vasoactive infusion score at the time of cannulation was 24.9 ± 43.9, at decannulation in survivors 4.6 ± 4.9 vs . 25.4 ± 21.5 in nonsurvivors, and 2.7 ± 4.9 at 48 hours post decannulation. On echocardiography, the average visual estimate of RV systolic function encoded (0 = none and 5 = severe) in survivors was 3.9 ± 1.2, 2.8 ± 1.6, 2.5 ± 1.7, and 2.8 ± 1.9, respectively, and in nonsurvivors 3.8 ± 1.6 and 3.4 ± 1.8, respectively. This demonstrated an RV systolic function improvement over time in survivors as opposed to nonsurvivors. This was also demonstrated in RV size visual estimate, respectively. Quantitatively, at the predefined four timepoints, the RV:LV, tricuspid annular plane systolic excursion, and fractional area change all improve over time and there is statistically significant difference in survivors versus nonsurvivors. In this study, we describe a cohort of patients treated with RA-PA DLSC RVAD. We illustrate the critical nature of echocardiographic measures to rate the progression of RV function, improvement in vasoactive infusion requirements, and ventilator parameters with the RA-PA DLSC.

Percutaneous mechanical thrombectomy in a real-world pulmonary embolism population: Interim results of the FLASH registry.

OBJECTIVES: The FlowTriever All-Comer Registry for Patient Safety and Hemodynamics (FLASH) is a prospective multi-center registry evaluating the safety and effectiveness of percutaneous mechanical thrombectomy for treatment of pulmonary embolism (PE) in a real-world patient population (NCT03761173). This interim analysis reports outcomes for the first 250 patients enrolled in FLASH. BACKGROUND: High- and intermediate-risk PEs are characterized by high mortality rates, frequent readmissions, and long-term sequelae. Mechanical thrombectomy is emerging as a front-line therapy for PE that enables immediate thrombus reduction while avoiding the bleeding risks inherent with thrombolytics. METHODS: The primary endpoint is a composite of major adverse events (MAE) including device-related death, major bleeding, and intraprocedural device- or procedure-related adverse events at 48 h. Secondary endpoints include on-table changes in hemodynamics and longer-term measures including dyspnea, heart rate, and cardiac function. RESULTS: Patients were predominantly intermediate-risk per ESC guidelines (6.8% high-risk, 93.2% intermediate-risk). There were three MAEs (1.2%), all of which were major bleeds that resolved without sequelae, with no device-related injuries, clinical deteriorations, or deaths at 48 h. All-cause mortality was 0.4% at 30 days, with a single death that was unrelated to PE. Significant on-table improvements in hemodynamics were noted, including an average reduction in mean pulmonary artery pressure of 7.1 mmHg (22.2%, p < 0.001). Patient symptoms and cardiac function improved through follow-up. CONCLUSIONS: These interim results provide preliminary evidence of excellent safety in a real-world PE population. Reported outcomes suggest that mechanical thrombectomy can result in immediate hemodynamic improvements, symptom reduction, and cardiac function recovery.

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.

Intermediate-Term Outcomes for Patients with Submassive Pulmonary Embolism Treated With Catheter-Directed Thrombolysis.

OBJECTIVE: We aimed to assess the intermediate-term outcomes for patients receiving catheter-directed thrombolysis (CDT) for submassive pulmonary embolism (PE). BACKGROUND: Previous research has shown improvements in right ventricular (RV) function and dilation at 24 hours when CDT was used to treat submassive PE. METHODS: Consecutive patients presenting with submassive PE treated with directed t-PA infusion at a single center were identified and included in this study. Outcomes included cardiovascular mortality, RV function by echocardiogram, 30-day readmission, and major bleeding. RESULTS: The study population was 79 patients with submassive PE; 46% were men, with an average age of 58 years and an average pulmonary embolism severity index (PESI) score of 108. One patient died of cardiovascular causes during the index hospitalization. There were no additional deaths within 30 days of admission. The observed 30-day mortality rate was low compared with that predicted by PESI (1.3% vs 4.0%-11.4%). Fifty-two patients had follow-up echocardiography available for evaluation after CDT. Of these, 62% showed return to normal RV function and size, and 19% demonstrated mild residual RV dysfunction or dilation. Eight patients (10%) had a hospital readmission within 30 days of discharge, including 6 admissions due to cardiopulmonary complications or minor bleeding and 2 for non-cardiopulmonary or bleeding-related reasons. The observed readmission rate of 10% was similar to historic rates of 12.8%. CONCLUSIONS: Intermediate-term follow-up for CDT demonstrates high success rates with low adverse event rates. Further randomized data are needed to study the long-term benefits of CDT.

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.

Percutaneous thrombectomy in patients with massive and very high-risk submassive acute pulmonary embolism.

OBJECTIVE: Examine FlowTriever thrombectomy feasibility in high-risk PE patients. BACKGROUND: The FlowTriever thrombectomy system (Inari Medical, Irvine, CA) can reduce right ventricle (RV) strain in acute submassive pulmonary embolism (PE) patients. This technology has not been studied in higher risk PE patients. METHODS: This multicenter retrospective analysis included patients treated with FlowTriever between 2017 and 2019 if they met at least one of the following: vasopressor dependence, PE induced respiratory failure, or decreased cardiac index (CI) measured by right heart catheterization. RESULTS: Analysis included 34 patients: 18 massive, four intubated, 12 normotensive but with CI < 1.8. Average age was 56 and their median simplified PE severity index was 2. Patients had high bleeding risk, with 13 having recent surgery, six posttrauma, and four recent strokes. Six patients received cardiopulmonary resuscitation, and two received additional mechanical circulatory support. All patients had RV dilatation and elevated biomarkers. Clot removal was successful in 32/34 patients. CI improved from 2.0 ± 0.1 L/min/m2 before thrombectomy to 2.4 ± 0.1 L/min/m2 after (p = .01). The mean pulmonary artery pressure decreased from 33.2 ± 1.6 mmHg to 25.0 ± 1.5 mmHg (p = .01). The two patients-both with no or minimal thrombus removed-deteriorated during the procedure: one died and the other was successfully stabilized on ECMO. There were no other major complications. All other patients were alive at the time of data collection (mean follow-up of 205 days). CONCLUSION: Aspiration thrombectomy appears feasible in higher risk acute PE patients with immediate hemodynamic improvement and low in-hospital mortality.

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.

Outcomes of catheter-directed versus systemic thrombolysis for the treatment of pulmonary embolism: A real-world analysis of national administrative claims.

Catheter-directed thrombolysis (CDT) and systemic thrombolysis (ST) are used to treat intermediate/high-risk pulmonary embolism (PE) in the absence of comparative safety and effectiveness data. We utilized a large administrative database to perform a comparative safety and effectiveness analysis of catheter-directed versus systemic thrombolysis. From the Optum® Clinformatics® Data Mart private-payer insurance claims database, we identified 100,744 patients hospitalized with PE between 2004 and 2014. We extracted demographic characteristics, high-risk PE features, components of the Elixhauser Comorbidity Index, and outcomes including intracranial hemorrhage (ICH), all-cause bleeding, and mortality among all patients receiving CDT and ST. We used propensity score methods to compare outcomes between matched cohorts adjusted for observed confounders. A total of 1915 patients (1.9%) received either CDT (n = 632) or ST (n = 1283). Patients in the CDT group had fewer high-risk features including less shock (5.4 vs 11.1%; p < 0.001) and cardiac arrest (6.8 vs 11.0%; p = 0.004). In 1:1 propensity-matched groups, ICH rates were 1.9% in both the CDT and ST groups (p = 1.0). All-cause bleeding was higher in the CDT group (15.9 vs 8.7%; p < 0.001), while in-hospital mortality was lower (6.5 vs 10.0%; p = 0.02). Among a nationally representative cohort of patients with PE at higher risk for mortality, CDT was associated with similar ICH rates, increased all-cause bleeding, and lower short and intermediate-term mortality when compared with ST. The competing risks and benefits of CDT in real-world practice suggest the need for large-scale randomized clinical trials with appropriate comparator arms.

Interventional Therapies in Acute Pulmonary Embolism.

Treatment of acute pulmonary embolism (PE) historically included anticoagulation and systemic thrombolytic therapy. More recently, catheter guided interventions provided promise of mitigating bleeding risks usually associated with systemic thrombolysis in intermediate to high risk PE patients. Catheter based interventions can broadly be divided into catheter directed thrombolysis and catheter based embolectomy. Both modalities are currently undergoing active research and each has their respective risks and benefits. The decision to administer these advanced therapies for acute PE can be challenging but can be accomplished via a multi-disciplinary PE response team.

Invasive hemodynamic assessment of patients with submassive pulmonary embolism.

OBJECTIVES: To investigate the invasive hemodynamics in patients with intermediate-risk pulmonary embolism (PE) and the change that occurs with catheter-directed thrombolysis (CDT). BACKGROUND: Intermediate-risk PE is associated with right ventricular strain and worse outcomes yet the invasive hemodynamics have not been well described. METHODS: Ninety-two consecutive patients with intermediate-risk PE referred for CDT at two tertiary medical centers with Pulmonary Embolism Response Teams were included in this prospective cohort study. Hemodynamics at baseline and after CDT therapy was measured. Patients with cardiac index (CI) ≤1.8 L min-1 m-2 were compared to those without shock (CI > 1.8). Linear regression analysis was performed to study the relationship between clinical variables and low CI. RESULTS: Thirty-seven out of 92 (40%) had a CI less than 1.8 L min-1 m-2 . When comparing the low CI to the normal CI groups, most demographics, vital signs, biomarkers, and PE severity index (PESI) scores were similar. The low CI group had more females and slightly lower systolic blood pressures although still in the normal range (122 vs. 132 mmHg, p = .026). Treatment with CDT was associated with significant improvement in CI, heart rate, and pulmonary artery pressures in both groups. Linear regression analysis did not reveal a strong correlation between CI and noninvasive metrics such as heart rate, blood pressure, or PESI score. CONCLUSIONS: Forty percent of patients with submassive PE had a depressed CI and treatment with CDT lead to hemodynamic improvements. Invasive hemodynamics may help better identify higher risk patients and guide therapy.

A Prospective, Single-Arm, Multicenter Trial of Catheter-Directed Mechanical Thrombectomy for Intermediate-Risk Acute Pulmonary Embolism: The FLARE Study.

OBJECTIVES: The aim of this study was to evaluate the safety and effectiveness of percutaneous mechanical thrombectomy using the FlowTriever System (Inari Medical, Irvine, California) in a prospective trial of patients with acute intermediate-risk pulmonary embolism (PE). BACKGROUND: Catheter-directed thrombolysis has been shown to improve right ventricular (RV) function in patients with PE. However, catheter-directed thrombolysis increases bleeding risk and many patients with PE have relative and absolute contraindications to thrombolysis. METHODS: Patients with symptomatic, computed tomography-documented PE and RV/left ventricular (LV) ratios ≥0.9 were eligible for enrollment. The primary effectiveness endpoint was core laboratory-assessed change in RV/LV ratio. The primary safety endpoint comprised device-related death, major bleeding, treatment-related clinical deterioration, pulmonary vascular injury, or cardiac injury within 48 h of thrombectomy. RESULTS: From April 2016 to October 2017, 106 patients were treated with the FlowTriever System at 18 U.S. sites. Two patients (1.9%) received adjunctive thrombolytics and were analyzed separately. Mean procedural time was 94 min; mean intensive care unit stay was 1.5 days. Forty-three patients (41.3%) did not require any intensive care unit stay. At 48 h post-procedure, average RV/LV ratio reduction was 0.38 (25.1%; p < 0.0001). Four patients (3.8%) experienced 6 major adverse events, with 1 patient (1.0%) experiencing major bleeding. One patient (1.0%) died, of undiagnosed breast cancer, through 30-day follow-up. CONCLUSIONS: Percutaneous mechanical thrombectomy with the FlowTriever System appears safe and effective in patients with acute intermediate-risk PE, with significant improvement in RV/LV ratio and minimal major bleeding. Potential advantages include immediate thrombus removal, absence of thrombolytic complications, and reduced need for post-procedural critical care.

Postoperative outcomes and management strategies for coronary artery disease in patients in need of a lung transplantation.

BACKGROUND: Patients requiring lung transplantation (LTx) may also have coronary artery disease (CAD). The peri-operative management and long-term outcomes of these patients are not well established. METHODS: Patients referred for LTx from 2008 to 2014 were included in this study. CAD was defined by angiography as no CAD (stenosis <20%), moderate CAD (20%-69%), and significant CAD (stenosis ≥70%). Revascularization was per recommendations of local heart team. Postoperative cardiovascular outcomes and long-term survival are reported. RESULTS: A total of 1493 patients were screened for LTx during this period and 656 received a transplant. Of the patients that underwent LTx, 51% had no CAD, 33% had moderate non-obstructive CAD, and 16% had obstructive CAD. Forty-three patients underwent revascularization. There was a no increased risk of peri-operative cardiovascular events or for adjusted mortality for patients with obstructive CAD (HR=1.24, 95% CI: 0.83-1.86, P=.290) including those requiring revascularization. CONCLUSIONS: There is a high prevalence of coronary disease in the population of patients with advanced lung disease requiring lung transplantation. Careful evaluation and treatment can allow for patients with all severities of CAD including those requiring revascularization to successfully undergo LTx.

Assessment of P2Y12 inhibitor usage and switching in acute coronary syndrome patients undergoing percutaneous coronary revascularization.

BACKGROUND: Dual antiplatelet therapy is recommended for patients with acute coronary syndrome (ACS) that undergo percutaneous coronary intervention (PCI). However, the effect of switching P2Y12 inhibitors between the loading dose and therapy after discharge is not well described. METHODS: This post-hoc analysis of a prospectively collected registry included 3219 consecutive ACS patients who underwent PCI. Patients were categorized into four groups: clopidogrel at load and discharge (C-C), loading dose of clopidogrel and discharged on prasugrel/ticagrelor (C-PT), loading dose of prasugrel/ticagrelor and discharged on clopidogrel (PT-C), and prasugrel/ticagrelor at load and discharge (PT-PT). RESULTS: While 77.6% of patients received the C-C treatment regimen and 13.6% received the PT-PT strategy, the strategy of P2Y12 switching was fairly common with 6.2% in the PT-C group and 2.6% in the C-PT group. While C-C was the most common treatment regimen, PT-C and PT-PT were more commonly used in STEMI patients than in NSTEMI or unstable angina patients. A significantly lower unadjusted incidence of the composite outcome (death, MI, and repeat revascularization) was appreciated in both the PT-C (1.0%) and PT-PT (2.3%) groups than the C-C group (4.0%). Propensity-score matched analysis still showed significantly reduced risk (HR=0.22, 95% CI 0.05-0.93, p=0.04) in the PT-C group vs. a matched group of C-C controls. CONCLUSIONS: The strategy of utilizing a newer P2Y12 inhibitor and then switching to clopidogrel in ACS patients following PCI is used with some frequency in routine clinical practice and further studies should evaluate the safety and efficacy of such a strategy.