One-Year Clinical Outcomes Following Mechanical Thrombectomy for Deep Vein Thrombosis: A CLOUT Registry Analysis.

Background: Mechanical thrombectomy is a promising treatment option for deep vein thrombosis; however, long-term data are lacking. Here, we report for the first time the 1-year clinical outcomes from the completely enrolled ClotTriever Outcomes (CLOUT) registry evaluating mechanical thrombectomy with the ClotTriever System (Inari Medical). Methods: The CLOUT registry (NCT03575364) is a prospective, multicenter, single-arm study that enrolled 500 patients with proximal lower extremity deep vein thrombosis. Prespecified 1-year outcomes include Villalta score and corresponding postthrombotic syndrome (PTS) severity, duplex ultrasound findings of patency (defined as the presence of flow with normal or partial compressibility), Revised Venous Clinical Severity Score, and quality of life (QoL). Results: In CLOUT, the median age was 61.9 years and 50.5% of patients were women. A total of 310 patients completed the 1-year visit. The 1-year PTS rate (Villalta score ≥ 5) was 19.3% and the moderate-to-severe PTS rate (Villalta score ≥ 10) was 8.8%. Median Villalta score decreased from 9.0 (IQR, 5.0-14.0) at baseline to 1.0 (IQR, 0.0-4.0) at 1 year (P < .0001). Similar rates of PTS and moderate-to-severe PTS were observed among limbs assessed at all study time points. Patency was observed in 94.2% of limbs. Median Revised Venous Clinical Severity Score was 6.0 (IQR, 3.0-9.0) at baseline and 3.0 (IQR, 1.0-4.0) at 1 year (P < .0001). Additionally, 90.4% of patients experienced improvements in QoL. Conclusions: One-year outcomes from the CLOUT registry demonstrate low PTS rates and preserved patency accompanied by improved symptom relief and QoL. Study follow-up through 2 years is ongoing.

Mechanical Thrombectomy for High-Risk Pulmonary Embolism: Insights From the US Cohort of the FLASH Registry.

Background: Acute mortality for high-risk, or massive, pulmonary embolism (PE) is almost 30% even when treated using advanced therapies. This analysis assessed the safety and effectiveness of mechanical thrombectomy (MT) for high-risk PE. Methods: The prospective, multicenter FlowTriever All-comer Registry for Patient Safety and Hemodynamics (FLASH) study is designed to evaluate real-world PE patient outcomes after MT with the FlowTriever System (Inari Medical). In this study, acute outcomes through 30 days were evaluated for the subset of patients with high-risk PE as determined by the sites and following European Society of Cardiology guidelines. An independent medical monitor adjudicated adverse events (AEs), including major AEs: device-related mortality, major bleeding, or intraprocedural device-related or procedure-related AEs. Results: Of the 799 patients in the US cohort, 63 (7.9%) were diagnosed with high-risk PE; 30 (47.6%) patients showed a systolic blood pressure <90 mm Hg, 29 (46.0%) required vasopressors, and 4 (6.3%) experienced cardiac arrest. The mean age of patients with high-risk PE was 59.4 ± 15.6 years, and 34 (54.0%) were women. At baseline, 45 (72.6%) patients were tachycardic, 18 (54.5%) showed elevated lactate levels of ≥2.5 mM, and 21 (42.9%) demonstrated depressed cardiac index of <2 L/min/m2. Immediately after MT, heart rate improved to 93.5 ± 17.9 bpm. Twenty-five (42.4%) patients did not require an overnight stay in the intensive care unit, and no mortalities or major AEs occurred through 48 hours. Moreover, no mortalities occurred in 61 (96.8%) patients followed up through the 30-day visit. Conclusions: In this cohort of 63 patients with high-risk PE, MT was safe and effective, with no acute mortalities reported. Further prospective data are needed in this population.

A Safety and Feasibility Single-Arm Study of a Novel Catheter Thrombectomy Device for the Treatment of Pulmonary Embolism (ENGULF).

Background: Despite advances in therapy options, pulmonary embolism (PE) continues to carry a high risk of mortality and morbidity. Currently, therapeutic options are limited with only 2 US Food and Drug Administration-cleared catheter-based embolectomy devices approved for the treatment of intermediate-risk PE. The novel Helo PE thrombectomy catheter (Endovascular Engineering, Inc) has a flexible and collapsible funnel with an internal agitator for a dual mechanism of treatment for acute PE. We sought to investigate the safety and feasibility of the novel Helo PE thrombectomy catheter in intermediate-risk PE. Methods: A prospective, single-arm feasibility study evaluating the Helo PE catheter was performed in patients presenting with intermediate-risk PE. Patients underwent preprocedural and postprocedural computed tomography angiography. Primary efficacy was the difference in preprocedural to postprocedural right ventricle/left ventricle (RV/LV) ratio. Primary and secondary safety outcomes were all-cause mortality, major life-threatening bleeding, device-related serious adverse events, pulmonary or cardiac injury, and clinical decompensation at 48 hours postprocedure and at 30 days. Results: A total of 25 patients from 8 centers were consented and included in the analysis. Preprocedural computed tomography angiography revealed an RV/LV ratio of 1.53 ± 0.27. All patients underwent a successful thrombectomy procedure. Postprocedure, the RV/LV ratio was reduced to 1.15 ± 0.18, translating into a 23.2 ± 12.81% decrease from baseline. No patients underwent adjunctive thrombolysis. Two patients had adjunctive catheter-directed embolectomy with an alternative device. Two patients had postprocedural anemia requiring transfusion but did not meet criteria for major life-threatening bleeding by VARC-2 criteria. There were no major adverse events including no deaths, major bleeding, pulmonary injury, or vascular complications at 48 hours or 30 days post procedure. Conclusions: In this multicenter first-in-human study, use of the Helo PE thrombectomy catheter was feasible and safe for the treatment of acute PE.

Six-Month Outcomes of Mechanical Thrombectomy for Treating Deep Vein Thrombosis: Analysis from the 500-Patient CLOUT Registry.

PURPOSE: Mechanical thrombectomy for the treatment of deep vein thrombosis (DVT) is being increasingly utilized to reduce symptoms and prevent postthrombotic syndrome (PTS), but more data on clinical outcomes are needed. Mechanical thrombectomy was studied in the ClotTriever Outcomes (CLOUT) registry with 6-month full analysis outcomes reported herein. MATERIALS AND METHODS: The CLOUT registry is a prospective, all-comer study that enrolled 500 lower extremity DVT patients across 43 US sites treated with mechanical thrombectomy using the ClotTriever System. Core-lab assessed Marder scores and physician-assessed venous patency by duplex ultrasound, PTS assessment using Villalta score, venous symptom severity, pain, and quality of life scores through 6 months were analyzed. Adverse events were identified and independently adjudicated. RESULTS: All-cause mortality at 30 days was 0.9%, and 8.6% of subjects experienced a serious adverse event (SAE) within the first 30 days, 1 of which (0.2%) was device related. SAE rethrombosis/residual thrombus incidence was 4.8% at 30 days and 8.0% at 6 months. Between baseline and 6 months, venous flow increased from 27.2% to 92.5% of limbs (P < 0.0001), and venous compressibility improved from 28.0% to 91.8% (P < 0.0001), while median Villalta scores improved from 9.0 at baseline to 1.0 at 6 months (P < 0.0001). Significant improvements in venous symptom severity, pain, and quality of life were also demonstrated. Outcomes from iliofemoral and isolated femoral-popliteal segments showed similar improvements. CONCLUSION: Outcomes from the CLOUT study, a large prospective registry for DVT, indicate that mechanical thrombectomy is safe and demonstrates significant improvement in symptoms and health status through 6 months. Level of Evidence 3: Non-randomized controlled cohort/follow-up study.

A Critical Review of Icosapent Ethyl in Cardiovascular Risk Reduction.

Icosapent ethyl (IPE) was the first fish oil product the US Food and Drug Administration (FDA) approved to reduce the risk of atherosclerotic cardiovascular disease (ASCVD) in adults. IPE is an esterified version of eicosapentaenoic acid (EPA) and acts as a prodrug in the body to exert its effects. IPE affects the body primarily through triglyceride (TG) reduction and was initially indicated for hypertriglyceridemia in addition to statin therapy or for patients with statin intolerances. Various studies have investigated this agent, and multiple subanalyses have been conducted since the FDA approval. These subanalyses have assessed factors such as sex, statin therapy, high-sensitivity C-reactive protein levels (hs-CRP), and various inflammatory biomarkers in groups of patients taking IPE. This article aims to provide a critical review of the clinical data available regarding cardiovascular benefits of IPE in patients with ASCVD and its value as a treatment option for patients with elevated TG levels.

Safety and Effectiveness of Mechanical Thrombectomy From the Fully Enrolled Multicenter, Prospective CLOUT Registry.

Background: We report in-hospital outcomes from the multicenter, prospective, single-arm ClotTriever Outcomes (CLOUT) registry, which enrolled up to 500 patients with proximal lower extremity deep vein thrombosis (DVT) treated with percutaneous mechanical thrombectomy using the ClotTriever System (Inari Medical). Methods: The CLOUT registry enrolled all-comer patients with DVT, irrespective of symptom duration, thrombus age, prior treatment of the current DVT, or bilateral thrombus. The primary effectiveness end point was defined as complete or near complete (≥75%) reduction in Marder score. Thrombus burden was assessed by an independent core laboratory. Mortality and serious adverse events, including device-relatedness, were adjudicated by an independent medical monitor. Here, safety and outcomes are evaluated through discharge. Results: The median age was 61.9 years (IQR, 48.0-70.8), 50.5% were women, 24.9% had a history of DVT, and 23.2% had previously failed treatment of the current DVT. Nearly all procedures (99.4%) were performed in a single session with negligible procedural blood loss (median 40.0 mL; IQR, 20.0-50.0), and most patients (97.8%) required no subsequent intensive care unit monitoring. The primary effectiveness end point was achieved in 91.2% of limbs. Through discharge, 1 device-related serious adverse event (0.2%) occurred. Health status, as assessed by self-reported pain and circumferential measurements of limb edema, were significantly improved at discharge. Conclusions: Thrombectomy with the ClotTriever System is a safe and effective treatment for proximal lower extremity DVT, while also avoiding the need of intensive care. Early patient improvements are demonstrated, and follow-up is ongoing to 2 years.

Longer-Term Outcomes Following Mechanical Thrombectomy for Intermediate- and High-Risk Pulmonary Embolism: 6-Month FLASH Registry Results.

Background: Mechanical thrombectomy provides rapid hemodynamic improvements after acute pulmonary embolism (PE), but long-term benefits are uncertain. Methods: FlowTriever All-comer Registry for Patient Safety and Hemodynamics is a prospective, single-arm, multicenter registry of patients with acute PE treated with the FlowTriever System (Inari Medical). Six-month outcomes including modified Medical Research Council dyspnea scores (MMRCD), right ventricular (RV) function, 6-minute walk test distances, and PE quality-of-life scores (QoL) were assessed. Results: In total, 799 patients were enrolled and 75% completed the study with a mean follow-up of 204 ± 46 days. Demographic characteristics included 54.1% men, mean age of 61.2 years, 77.1% intermediate-high-risk PE, and 8.0% high-risk PE. All-cause mortality was 4.6% at study completion. The proportion of patients with normal echocardiographic RV function increased from 15.1% at baseline to 95.1% at 6 months (P < .0001). MMRCD score improved from 3.0 at baseline to 0.0 at 6 months (P < .0001). 6-minute walk test distances increased from 180 m at 48 hours to 398 m at 6 months (P < .001). Median PE QoL total scores were 9.38 at 30 days and 4.85 at 6 months (P < .001). Prevalence of site-reported chronic thromboembolic pulmonary hypertension was 1.0% and chronic thromboembolic disease was 1.9%. Conclusions: In this large diverse group of PE patients, 6-month all-cause mortality, chronic thromboembolic pulmonary hypertension, and chronic thromboembolic disease were low following thrombectomy with the FlowTriever system. Significant improvements in RV function, patient symptoms, exercise capacity, and QoL were observed at 6 months, suggesting that rapid extraction of thrombus may prevent long-term sequelae in patients with PE.

Interim outcomes of mechanical thrombectomy for deep vein thrombosis from the All-Comer CLOUT Registry.

OBJECTIVES: The multicenter, prospective, single arm CLOUT registry assesses the safety and effectiveness of the ClotTriever System (Inari Medical, Irvine, CA) for the treatment of acute and nonacute lower extremity deep vein thrombosis (DVT) in all-comer patients. Reported here are the outcomes of the first 250 patients. METHODS: All-comer patients with lower extremity DVT were enrolled, including those with bilateral DVT, those with previously failed DVT treatment, and regardless of symptom duration. The primary effectiveness end point is complete or near-complete (≥75%) thrombus removal determined by independent core laboratory-adjudicated Marder scores. Safety outcomes include serious adverse events through 30 days and clinical outcomes include post-thrombotic syndrome severity, symptoms, pain, and quality of life through 6 months. RESULTS: The median age was 62 years and 40% of patients had contraindications to thrombolytics. A range of thrombus chronicity (33% acute, 35% subacute, 32% chronic) was observed. No patients received thrombolytics and 99.6% were treated in a single session. The median thrombectomy time was 28 minutes. The primary effectiveness end point was achieved in 86% of limbs. Through 30 days, one device-related serious adverse event occurred. At 6 months, 24% of patients had post-thrombotic syndrome. Significant and sustained improvements were observed in all clinical outcomes, including the Revised Venous Clinical Severity Score, the numeric pain rating scale, and the EuroQol Group 5-Dimension Self-Report Questionnaire. CONCLUSIONS: The 6-month outcomes from the all-comer CLOUT registry with a range of thrombus chronicities demonstrate favorable effectiveness, safety, and sustained clinical improvements.

A Review of the Clinical Pharmacology of Pelacarsen: A Lipoprotein(a)-Lowering Agent.

Patients with genetically associated elevated lipoprotein(a) [Lp(a)] levels are at greater risk for coronary artery disease, heart attack, stroke, and peripheral arterial disease. To date, there are no US FDA-approved drug therapies that are designed to target Lp(a) with the goal of lowering the Lp(a) level in patients who have increased risk. The American College of Cardiology (ACC) has provided guidelines on how to use traditional lipid profiles to assess the risk of atherosclerotic cardiovascular disease (ASCVD); however, even with the emergence of statin add-on therapies such as ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, some populations with elevated Lp(a) biomarkers remain at an increased risk for cardiovascular (CV) disease. Residual CV risk has led researchers to inquire about how lowering Lp(a) can be used as a potential preventative therapy in reducing CV events. This review aims to present and discuss the current clinical and scientific evidence pertaining to pelacarsen.

Inferior vena cava filter migration to the right ventricle causing nonsustained ventricular tachycardia.

Inferior vena cava filters are commonly used to prevent pulmonary embolism in patients who manifest deep vein thrombosis and recurrent pulmonary embolism despite anticoagulation, or in patients with contraindications to anticoagulation. We report the case of a 69-year-old man with a structurally normal heart who experienced migration of an inferior vena cava filter to the right ventricle, which caused the abrupt onset of recurrent episodes of nonsustained ventricular tachycardia unresponsive to intravenous antiarrhythmic medication. Cardiac imaging revealed the location of the filter within the right ventricle, and the device was removed, with subsequent resolution of the arrhythmia. We anticipate that the incidence of inferior vena cava filter migration might increase in the future because of recent changes in device construction. The sudden appearance of nonsustained ventricular tachycardia in a patient with an inferior vena cava filter might indicate the occurrence of this potentially life-threatening sequela and should lead to emergent cardiac imaging.

Primary Streptococcus pneumoniae pericarditis.

Although commonly fatal, bacterial pericarditis is often not diagnosed antemortem due to its infrequent occurrence and fulminant course. Historically, Streptococcus pneumoniae has been the most common cause of bacterial pericarditis. Over the past 70 years, however, it has become largely eliminated and now occurs almost exclusively in immunocompromised individuals with a preceding primary site of infection. Herein, we present a case of primary S. pneumoniae pericarditis that developed over the course of 3 to 4 weeks in an immunocompetent 45-year-old man. The patient, who developed cardiac tamponade shortly after admission, experienced a rapid resolution of symptoms following pericardial drainage and initiation of antibiotics.

Effect of Hurricane Katrina on chronobiology at onset of acute myocardial infarction during the subsequent three years.

The onset of acute myocardial infarction (AMI) has been shown to occur in a nonrandom pattern, with peaks in midmorning and on weekdays (especially Monday). The incidence of AMI has been shown to increase locally after natural disasters, but the effect of catastrophic events on AMI biorhythms is largely unknown. To assess the differences in the chronobiology of AMI in residents of New Orleans before and after Hurricane Katrina, the onset of AMI in patients at Tulane University Health Sciences Center in the 6 years before and the 3 years after Hurricane Katrina was retrospectively examined. Compared to the pre-Katrina group, the post-Katrina cohort demonstrated significant decreases in the onset of AMI during mornings (p = 0.002), Mondays (p <0.0001), and weekdays (p <0.0001) and significant increases in onset during weekends (p <0.0001) and nights (p <0.0001). These changes persisted during all 3 years after the storm. In conclusion, the normal pattern of AMI onset was altered after Hurricane Katrina, and expected morning, weekday, and Monday peaks were eliminated.

Acute profound thrombocytopenia secondary to local abciximab infusion.

Glycoprotein (GP) IIb/IIIa receptor antagonists are powerful antiplatelet agents that are typically used in percutaneous coronary intervention. All three GP IIb/IIIa agents currently approved for use in the United States cause thrombocytopenia as a rare side effect. Abciximab is unique to the class in that it is a modified monoclonal antibody to the GP IIb/IIIa receptor, a property that can lead to increased platelet destruction. Presented herein is a patient who received a local infusion of abciximab for a lower-extremity thrombus and within 2 hours developed an acute profound thrombocytopenia that likely caused a large retroperitoneal hematoma. This case demonstrates the importance of checking platelet count within 2 to 4 hours after local (in addition to systemic) abciximab administration. Additionally, this report outlines how other causes of acute precipitous platelet drops, such as heparin-induced thrombocytopenia and pseudothrombocytopenia, can be rapidly excluded and allow for the prompt initiation of optimal therapy to minimize bleeding.

May-Thurner syndrome: a not so uncommon cause of a common condition.

May-Thurner syndrome is a rarely diagnosed condition in which patients develop iliofemoral deep venous thrombosis (DVT) due to an anatomical variant in which the right common iliac artery overlies and compresses the left common iliac vein against the lumbar spine. This variant has been shown to be present in over 20% of the population; however, it is rarely considered in the differential diagnosis of DVT, particularly in patients with other risk factors. Systemic anticoagulation alone is insufficient treatment, and a more aggressive approach is necessary to prevent recurrent DVT. Herein, we present a patient with multiple risk factors for DVT. With a comprehensive diagnostic approach, she was found to have May-Thurner syndrome. Local infusion of thrombolytics as well as mechanical thrombectomy failed to resolve the thrombus. Subsequently the patient underwent successful stent placement in the area that was compressed followed by 6 months of chronic anticoagulation with warfarin. There has been no recurrence of DVT in the ensuing 18 months.