How to initiate aspirational embolectomy program for pulmonary embolism: single centre initial experience
Authors: Pavlov M , Bodrozic Dzakic T , Blivajs A , Hadzibegovic I , Pavlovic N , Manola S 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Recent advances in percutaneous mechanical thrombectomy provide lytic-free methods for treatment of pulmonary embolism (PE). Although guidelines recommend aspirational embolectomy only for high-risk PE patients with contraindication to or failed fibrinolysis, the method is currently being used in treatment of intermediate-high risk PE patients. We present our initial experiences with large bore percutaneous aspirational embolectomy catheter.

Methods
Patients with intermediate-high risk PE and at least one clinical feature (persistent hypoxemia, tachycardia, hypotension without shock, or dyspnoea on minimal exertion) were considered eligible for the method. Positive high-sensitive troponin was obligatory. PE was diagnosed by computed tomography. Echocardiography and doppler ultrasound of lower limbs venous system were performed upon admission. All procedures were performed by interventional cardiologist in cardiology suite. Light sedation with dexmedetomidine and/or midazolam was used. Ultrasound guided right or left femoral approach was used in all patients. A 7F balloon tipped catheter was used to cross the tricuspid and pulmonary valves and engage pulmonary artery (PA). After exchanging for 6F pigtail catheter an angiography was performed. Then, via multipurpose 6F catheter an extra-stiff wire was introduced distal to the thrombus. Over the wire a 20F or 24F aspirational embolectomy catheter was placed in front of the thrombus followed by the aspiration with 60 ml syringe. Up to 10 aspirations were allowed. Unfractionated heparin was used for periprocedural anticoagulation followed by apixaban or rivaroxaban as soon as hemostasis was achieved. Patients outcomes were recorded prospectively.

Results
From March to October 2022 a total of 10 patients were treated with aspirational embolectomy (6 females, median age 68.5 years (interquartile range 53.25-74)). Only the first case was performed with 20F catheter. In 9 patients sheathless approach was used due to material unavailability. In one case switching to left-side access was required due to inability to introduce the catheter in common femoral vein. In two cases a "lollipop" phenomenon occurred, one of which was a thrombus-in-transit (TIT) case. This case was complicated with TIT fragmentation on exit and re-embolism with circulatory arrest requiring veno-arterial extracorporeal circulatory support. Procedural success was achieved in all cases (in TIT patient two procedures were needed). All patients reported improvements in dyspnea levels. One patient required oxygen supplementation beyond 24h (TIT patient). Average PA systolic and diastolic blood pressure drop was 24.3±11.0 and 12.3±4.9 mmHg. Nine patients were alive at discharge, while TIT patient was still requiring hospitalisation.

Conclusion
Aspirational embolectomy can provide sufficient drop in PA pressures and symptom relief. Randomised trials are needed to determine the long term outcomes of the procedure.