Ultrasound-Assisted Catheter-Directed Thrombolysis: A Novel and Promising Endovascular Therapeutic Modality for Intermediate-Risk Pulmonary Embolism

Abstract

Intermediate-risk pulmonary embolism (PE), also known as submassive PE, occurs in a substantial group of patients and carries a significant mortality risk. With adequate risk stratification, catheter-directed techniques could be used as a therapeutic approach in the intermediate-risk PE. Ultrasound-assisted catheter-directed thrombolysis (UCDT) represents a novel endovascular technique with good clinical and safety outcomes. Ultrasound-assisted catheter-directed thrombolysis can achieve reduction in the thrombus burden and improvement of pulmonary hemodynamics and right ventricular (RV) dysfunction and/or dilatation, without major procedure-related complications, major bleeding, or hemorrhagic strokes. This narrative review will focus on the major studies involving the efficacy and safety of UCDT in the intermediate-risk PE population. Prospective, randomized clinical trials with long-term follow-up and a large sample size are needed for further evaluation of mortality benefit and to further define which subgroup of patients may benefit from this novel endovascular technique.

Pulmonary Embolism Response Teams: A Novel Approach for the Care of Complex Patients With Pulmonary Embolism

“…In an effort to reduce the bleeding risk associated with systemic thrombolysis, CDT has emerged as a therapeutic alternative in patients who have intermediate- and high-risk PE. 11,27 -29 The thrombolytic agent can be administered via a multiside-hole infusion catheter or with the EkoSonic ultrasound-assisted catheter (EKOS, Corporation, Bothell, Washington). Ultrasound-assisted catheter-directed thrombolysis (UCDL) has shown to effectively reverse RV strain in 24 to 48 hours in patients with intermediate- and high-risk PE having low rates of major bleeding.…”

“…9 High risk, also known as massive PE, is defined as hemodynamic instability manifested by persistent hypotension with a systolic blood pressure of <90 mm Hg or cardiogenic shock and carries the highest mortality rate exceeding 50%. 10,11 Those patients with normotension and presence of right ventricular (RV) strain, by echocardiography, computed tomography angiography (CTA) and/or elevated cardiac biomarkers, are classified as intermediate-risk or submassive PE. Furthermore, recent European Society of Cardiology (ESC) guidelines propose dividing intermediate-risk into intermediate-high and intermediate-low risk.…”

Interventional radiology treatment for pulmonary embolism

“…The use of new devices for fragmentation and/or aspiration of the thrombi can improve these results. The use of ultrasound through a 5.4 Fr catheter with infusion of fibrinolytic leads to rapid lysis of the thrombi located in the pulmonary artery[40,50,51]. Seattle II, a prospective study of 150 patients diagnosed with massive or submassive PE using EKO-sonic and a low dose of r-TPA through CDT, reduced the RV/LV ratio measured with CT by 25% in 48 h, showed a 30% improvement of the systolic pressure and another 30% in the pulmonary artery obstruction[41].…”

Perioperative Acute Pulmonary Embolism: A Concise Review with Emphasis on Multidisciplinary Approach

“…The 2019 European Society of Cardiology (ESC) guidelines classify PE in three categories: high, intermediate, and low-risk PE. 5,16,17 High-risk PE (or massive PE), defined by hemodynamic instability manifested by persistent hypotension with a systolic blood pressure of <90 mm Hg or cardiogenic shock, carries the highest mortality rate exceeding up to 50%. 16 Patients without hemodynamic instability but presence of right ventricular (RV) dysfunction, either documented by echocardiography or computed tomographic pulmonary angiography (CTPA) and/or elevated biomarkers of myocardial injury (troponin and/or brain natriuretic peptide), are classified as intermediate-risk PE (or submassive PE).…”