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.

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.

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.

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.

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.

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.

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.

Extracorporeal membrane oxygenation support in acute coronary syndromes complicated by cardiogenic shock.

BACKGROUND: Acute coronary syndrome (ACS) complicated by shock is associated with high mortality despite the use of percutaneous support devices. Extracorporeal membrane oxygenation (ECMO) offers cardiopulmonary support but its safety and efficacy in the ACS setting is still under investigation. METHODS: We reviewed the clinical characteristics and course of 18 consecutive patients who received femoral veno-arterial ECMO in the cardiac catheterization lab for severe shock due to ACS at our center between 2007 and 2013. RESULTS: The average age was 59.9 years, 72.2% male. Of the 18 patients, 83% had a ST-segment elevation myocardial infarction, of which 55% had a left main or left anterior descending artery occlusion. Thirteen patients received stents, three were referred for coronary artery bypass grafting alone, and two received balloon angioplasty. All patients received aspirin, a thienopyridine (either clopidogrel or ticagrelor), and heparin. Five patients received a glycoprotein IIb/IIIa inhibitor during the catheterization. The average length of ECMO was 3.2 ± 2.5 days, length of stay was 23.4 days, and 67% survived to discharge. Seventeen of eighteen patients (94%) required at least one blood transfusion and use of blood products was significantly higher in the group receiving glycoprotein IIb/IIIa inhibitors [19 U of packed red blood cells (PRBC) vs. 8.2 U (P = 0.003)]. CONCLUSIONS: In patients with severe shock or refractory ventricular arrhythmias due to ACS, VA-ECMO likely offers an alternative form of biventricular support albeit with significant resource utilization and morbidity. A better understanding of how to manage patients with ACS requiring VA-ECMO support including the associated morbidities such as bleeding is necessary.

Identification of Intrastent Pathology Associated With Late Stent Thrombosis Using Optical Coherence Tomography.

OBJECTIVE: To better characterize intrastent pathology using optical coherence tomography (OCT) in patients presenting with late and very late stent thrombosis (LST/VLST). BACKGROUND: The contribution of specific intrastent pathologies to the development of LST/VLST is not well understood. METHODS: In this single-center, retrospective, observational study of 796 consecutive patients treated for ST-segment elevation myocardial infarction (STEMI) with primary PCI we identified 57 patients (7.2%) in whom STEMI resulted from LST/VLST. Of the patients with LST/VLST, 21 patients (37%) had OCT performed at the discretion of the operator during PCI for LST/VLST. Independent reviewers performed qualitative offline analysis of OCT images to determine the cause of stent thrombosis defined as the specific intrastent pathology associated with thrombus deposition. RESULTS: The principal intrastent pathology causing LST/VLST was determined to be stent malapposition in 11 patients (55%), of which 5 (25% of all LST/VLST patents) had findings suggestive of positive vessel remodeling. Neoatherosclerosis was determined to be the cause of LST/VLST in 7 patients (35%). LST/VLST resulted from uncovered stent struts in 2 patients (10%). Among all LST/VLST patients, in-hospital mortality (12.3%) and post-hospital target vessel failure (TVF) or cardiac death (21.7%, median follow-up 1.6 years) remained high. There was a trend towards decreased TVF or cardiac death (7.7% vs. 27.3% P = 0.24) in patients who underwent OCT-guided therapy. CONCLUSIONS: LST/VLST remains a significant cause of STEMI and is associated with considerable morbidity and mortality. OCT use at the time of PCI consistently identifies significant intrastent pathology with potentially meaningful clinical impact.

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.