Special Considerations in Pulmonary Embolism: Clot-in-Transit and Incidental Pulmonary Embolism

Management of high and intermediate-high risk pulmonary embolism: A position paper of the Interventional Cardiology Working Group of the Italian Society of Cardiology

Pulmonary embolism (PE) is a potentially life-threatening condition that remains a major global health concern. Noteworthy, patients with high- and intermediate-high-risk PE pose unique challenges because they often display clinical and hemodynamic instability, thus requiring rapid intervention to mitigate the risk of clinical deterioration and death. Importantly, recovery from PE is associated with long-term complications such as recurrences, bleeding with oral anticoagulant treatment, pulmonary hypertension, and psychological distress. Several novel strategies to improve risk factor characterization and management of patients with PE have recently been introduced. Accordingly, this position paper of the Working Group of Interventional Cardiology of the Italian Society of Cardiology deals with the landscape of high- and intermediate-high risk PE, with a focus on bridging the gap between the evolving standards of care and the current clinical practice. Specifically, the growing importance of catheter-directed therapies as part of the therapeutic armamentarium is highlighted. These interventions have been shown to be effective strategies in unstable patients since they offer, as compared with thrombolysis, faster and more effective restoration of hemodynamic stability with a consistent reduction in the risk of bleeding. Evolving standards of care underscore the need for continuous re-assessment of patient risk stratification. To this end, a multidisciplinary approach is paramount in refining selection criteria to deliver the most effective treatment to patients with unstable hemodynamics. In conclusion, the current management of unstable patients with PE should prioritize tailored treatment in a patient-oriented approach in which transcatheter therapies play a central role.

Clot-in-transit: A ticking time bomb in the heart with serious consequences

Clot-in-transit is associated with severe pulmonary embolism and higher mortality than acute pulmonary embolism without clot-in-transit. The optimal treatment of clot-in-transit is not established. Multiple treatment options have been described, including anticoagulation alone, systemic thrombolysis, surgical embolectomy and endovascular catheter-based therapies. Clot-in-transit can embolize to the pulmonary circulation in a matter of seconds and be immediately fatal. We describe two cases of clot-in-transit which embolized quickly upon Intensivist's evaluation and were associated with serious consequences. Management decisions for clot-in-transit should be emergent and based on multidisciplinary discussion of the pulmonary embolism response team.

Suction-based catheter retrieval of right ventricular clot-in-transit

Right ventricular clot-in-transit (CIT) is a rare finding in venous thromboembolic disease and carries a high mortality rate. Its optimal treatments have yet to be established in the literature. Here we describe the usage of a suction-based catheter, the INARI FlowTriever® system (INARI Medical Inc.) to successfully retrieve a CIT from the right ventricle of a patient with coronavirus disease 2019 acute respiratory distress syndrome on veno-veno extracorporeal membrane oxygenation.

Symptomatic pulmonary embolus after catheter removal in children with catheter related thrombosis: A report from the CHAT Consortium

BACKGROUND

Appropriate timing of central venous catheter (CVC) removal, in relation to start of anticoagulation, in children after the diagnosis of a CVC-related thrombosis (CRT) is not well established.

OBJECTIVES

This retrospective cohort study evaluated the incidence of symptomatic pulmonary embolism (PE) after CVC removal using data from the multi-institutional Children's Hospital-Acquired Thrombosis (CHAT) Consortium Registry.

PATIENTS/METHODS

The CHAT Registry consists of data from children aged 0-21 years with a hospital-acquired venous thromboembolism. Eligible subjects were those with CRT diagnosed <3 days after CVC removal. Subjects were excluded if the CRT was due to a failed CVC insertion. Subjects were divided into three groups: those with CVC removal without anticoagulation, those with CVC removal <48 h after starting anticoagulation, and those with CVC removal ≥48 h after starting anticoagulation.

RESULTS

A total of 687 CRT events from 663 subjects were included. A majority of CRT events were in subjects with peripherally inserted central catheters (62.3%, n = 428). For the 611 CRT events in which the CVC was removed, there was only one case of symptomatic PE (0.16%), which occurred <48 h after initiation of anticoagulation.

CONCLUSIONS

While current guidelines suggest anticoagulation before CVC removal in the setting of a CRT to prevent embolization, CVC removal is not associated with symptomatic PE regardless of duration of anticoagulation before CVC removal.

Prevalence, Outcome, and Optimal Management of Free-Floating Right Heart Thrombi in the Context of Pulmonary Embolism, a Systematic Review and Meta-Analysis

Free-floating right-heart thrombus (FFRHT) in the context of a pulmonary embolism (PE) is a rare but serious encounter with no guidelines addressing its management. We performed a systematic review and meta-analysis addressing prevalence, clinical behavior, and outcomes of FFRHT associated with PE. Among the included 397 patients with FFRHT and PE, dyspnea was the main presenting symptom (73.3%). Obstructive shock was documented in 48.9% of cases. Treatment with thrombolytic therapy, surgical thrombectomy, and percutaneous thrombectomy was documented in 43.8%, 32.7%, and 6.5% of patients, respectively. The overall mortality rate was 20.4%. Syncope ( p: 0.027), chest pain ( p: 0.006), and obstructive shock ( p: 0.037) were significantly associated with mortality. Use of thrombolytic therapy was significantly associated with survival ( p: 0.008). A multivariate logistic regression model to determine mortality predictors revealed that syncope (OR: 1.97, 95% CI: 1.06–3.65, p: 0.03), and obstructive shock (OR: 2.23, 95% CI: 1.20–4.14, p: 0.01) were associated with increased death odds. Treatment with thrombolytic therapy (OR: 0.22, 95% CI: 0.086–0.57, p: 0.002) or surgical thrombectomy (OR: 0.35, 95% CI: 0.137–0.9, p: 0.03) were associated with reduced death odds. Meta-analysis of observational studies revealed a pooled prevalence of FFRHT among all PE cases of 8.1%, and overall mortality of 23%. Although uncommon, the presence of FFRHT in the context of PE is associated with high obstructive shock and mortality rates. Favorable survival odds are observed with thrombolytic therapy and surgical thrombectomy. Data are derived from case reports and observational studies. Clinical trials elucidating these findings are needed.

Pulmonary CTA Reporting: AJR Expert Panel Narrative Review

Pulmonary CTA is a ubiquitous study interpreted by radiologists with different levels of experience in a variety of practice settings. Pulmonary embolism (PE) can range from an incidental and clinically insignificant finding to a clinically significant thrombus that can be managed on an outpatient basis to a potentially fatal condition requiring immediate medical or invasive management. Accordingly, a clear and concise pulmonary CTA report should effectively communicate the most pertinent findings to help the treating medical team diagnose or exclude the diagnosis of PE and provide information to guide appropriate management. In this expert panel narrative review, we discuss the purpose of the radiology report for pulmonary CTA, the optimal report format, the relevant findings that need to be addressed and their clinical significance.