AngioVac system guided removal of vegetations from pacemaker lead-related infective endocarditis

Abstract

The AngioVac aspiration system is a catheter-based technique that has been used for removal of unwanted intravascular material in growing numbers of institutions around the world since 2013. It provides an alternative and a less invasive approach for the treatment of venous thromboembolism and intrinsic or cardiac implantable electronic devices (CIED)-related infective endocarditis. This system uses venous cannulas and extracorporeal filtering mechanisms to effectively remove thrombi or vegetations resulting in less invasion and minimal blood loss. We present a case of a woman in her mid-50s who underwent successful AngioVac-guided removal of lead vegetations followed by percutaneous CIED removal.

Background

Cardiac implantable electronic devices (CIED) infections are generally considered in two categories, such as pocket infections and systemic infections. These infections have an unknown exact incidence but has been reported as about 1.18% per year and 2.06% per patient-year in some larger studies, and can lead to a 3.9%–9.6% mortality depending on the device and the level of infection.^1–3 Treatment of these infections involves removal of the intravascular infectious material as well as the device and lead material. An upcoming novel approach to the treatment of CIED infections involves the use of the AngioVac device. The AngioVac circuit effectively removes the unwanted intravascular materials by a vacuum and extracorporeal filter mechanism and is less invasive compared with the open surgical approach.

Case presentation

A woman in her mid-50s with a medical history of non-sustained ventricular tachycardia and syncope treated with implantable cardioverter-defibrillator (ICD), atrial fibrillation, hypertension and chronic obstructive pulmonary disease treated with supplemental oxygen was transferred to our hospital for further management of methicillin-sensitive Staphylococcus aureus (MSSA) septicaemia. She had presented to another hospital with confusion and was found to have blood cultures growing MSSA manifesting as fever.

Her vitals revealed temperature 37°C, heart rate 91 beats/minute, respiratory rate 22 breaths/minute, blood pressure 106/67 mm Hg and oxygen saturation 99% breathing 3 L/min oxygen via nasal cannula. Physical examination was unremarkable.

Investigations

Initial laboratory examination revealed white cell count 11.72×10⁹ /L, creatinine 1.37 mg/dL and creatine kinase 2005 U/L. The patient became febrile, and blood cultures were drawn, which grew MSSA. Two days later, blood cultures were drawn again which also grew MSSA.

Transthoracic echocardiogram was performed which did not reveal any abnormality. Transoesophageal echocardiography (TEE) was performed, which revealed a bulky mass/vegetation adherent to the ICD lead in the right atrium (RA). Later, during surgical procedure for removal of vegetations and ICD, TEE was performed which showed several vegetations attached to the ICD lead at the junction of inferior vena cava (IVC) and tricuspid annulus, largest of which measured 3.5 cm in diameter (figure 1, video 1). Another vegetation attached to the ICD lead was observed in the superior vena cava (SVC). Aerobic cultures from ICD lead and vegetations later grew MSSA, but the ICD generator culture did not reveal any growth. Blood cultures were rechecked, not revealing any growth.

Figure 1.

Intraoperative TEE image of vegetation. A 90° mid-oesophageal modified bicaval view demonstrating vegetation (encircled) attached to the ICD lead in RA. ICD, implantable cardioverter-defibrillator; LA, left atrium; RA, right atrium; RV, right ventricle; TEE, transoesophageal echocardiography.

Video 1. Intraoperative TEE. A 84° mid-oesophageal modified bicaval view demonstrating the vegetation attached to ICD lead in the RA. ICD, implantable cardioverter-defibrillator; RA, right atrium; TEE, transoesophageal echocardiography.

bcr-2022-251097supp001.mp4 ^{(668.9KB, mp4)}

DOI: 10.1136/bcr-2022-251097.video01

Differential diagnosis

Given the patient’s age, her medical history and MSSA positive blood cultures, the differential diagnosis included skin and soft tissue infections, osteomyelitis or infections of indwelling prosthetic devices such as CIED, intravascular catheters and orthopaedic hardware.

Treatment

Initial treatment at another hospital was started with intravenous fluids, vancomycin and levofloxacin for broad-spectrum antimicrobial coverage. It was then changed to ceftriaxone after blood cultures reported MSSA. The patient was admitted to our hospital and antibiotic was switched to cefazolin to treat MSSA. Blood cultures were redrawn revealing MSSA. Infectious disease service was consulted, and ertapenem was added for persistent MSSA bacteraemia as combination beta-lactam therapy has shown beneficial results for persistent MSSA bacteremia cases.⁴ Transthoracic echocardiogram was performed which did not reveal any abnormality. TEE was performed, which revealed a bulky mass/vegetation adherent to the ICD lead in the RA. Blood cultures were repeated and were negative. Since the vegetation was >20 mm in diameter, the ideal treatment approach included open surgical removal of vegetations and leads. However, due to multiple significant comorbidities, the patient was deemed a poor surgical candidate. A multidisciplinary approach with cardiothoracic surgery and electrophysiology services was planned with transvenous lead extraction and AngioVac device-guided vegetation removal.

Intraoperative TEE revealed several vegetations attached to the ICD lead. Right and left femoral venous access was ultimately achieved with 26 Fr sheath and 19 Fr cannula with serial dilators, and the sheaths were connected to external veno-venous pump. The AngioVac device was advanced through the 26 Fr sheath and progressively moved into the SVC, low RA, close to the IVC-RA junction and RV ICD lead while the suction was on with 3 L/min flow. This was performed in close collaboration with the intraoperative TEE (video 2). The burden of vegetations was noticed to significantly decrease over time, as seen on the TEE. The AngioVac device was then removed, and the pump was turned off. This was followed by ICD lead removal. After multiple attempts to extract the ICD lead using superior and inferior approach, the lead was finally removed by the inferior approach as a single unit along with the 26 Fr right femoral vein sheath. The ICD generator pocket was then irrigated with antibiotic solution and closed in layers.

Video 2. AngioVac catheter engaging ICD vegetation. A 100° mid-oesophageal modified bicaval view demonstrating AngioVac catheter guided engaging of the vegetation attached to the ICD lead in the RA. ICD, implantable cardioverter-defibrillator; RA, right atrium.

bcr-2022-251097supp002.mp4 ^{(668.9KB, mp4)}

DOI: 10.1136/bcr-2022-251097.video02

The lead and vegetations cultures later grew MSSA, but the generator culture did not reveal any growth. Blood cultures were drawn again but did not grow any organism this time. Ertapenem was discontinued. The patient was discharged later and prescribed intravenous cefazolin for a total of 6 weeks through a peripherally inserted central catheter (PICC).

Outcome and follow-up

The patient did not have any complaints in the follow-up visit 4 days later. She completed her course of antibiotics and PICC was removed.

Discussion

Right-sided cardiac thrombi or vegetations are associated with a 23%–40% risk of pulmonary embolism, leading to increased haemodynamic instability, morbidity and mortality.⁵ Patients with CIED and leads on the right side of the heart can also develop infections associated with the device. The exact incidence of CIED infections is unknown. Some studies have shown an infection rate of 1.18% per year, some have shown it to be 2.06% per patient-year, while others have shown a lifetime risk of 1.2%–3.4%.^{1 2 6} Overall mortality of these infections varies from 3.9% to 9.6% depending on the nature of the infected device.

For patients with CIED infections, the grade I recommendation and standard of care is transvenous lead extraction with the goal of complete removal of the infected device and the lead material.⁷ Percutaneous lead extraction is usually safe for patients with small vegetations.⁸ On the other hand, for patients with vegetations larger than 20 mm in diameter, there is an increased risk of pulmonary embolism of the vegetation during percutaneous lead extraction.⁹ In a case series by Meier-Ewert et al, it was reported that 55% of patients with vegetations on endocardial leads experienced pulmonary embolism during lead extraction.¹⁰ The risk of pulmonary embolism increases significantly with the size of the thrombi/vegetation.

Due to the high risk, the standard of care thus far for such patients has been open surgical lead extraction and debridement.¹¹ However, open surgical removal is associated with a high risk of complications such as respiratory failure, delaying the recovery time and increasing the cost of care.¹² A vacuum-assisted device known as the AngioVac system, combined with endovascular lead extraction, allows for a safer alternative for patients at a high operative risk and a high risk for pulmonary embolisation. A study by Schaerf et al showed decreased risk of perioperative sepsis due to vegetation embolisation with the use of AngioVac system, thereby potentially reducing the morbidity and mortality.¹³ Adopting a multidisciplinary approach and deciding the treatment modality based on individual cases has resulted in successful outcomes.

The AngioVac system is manufactured by Vortex Medical for AngioDynamics and was approved for the removal of unwanted intravascular central venous thrombi and vegetations in 2014 by the US Food and Drugs Administration. It is a catheter-based system that allows for suction, filtering and reinfusion of blood into the venous system. The device consists of a venous drainage cannula, an extracorporeal centrifugal pump and console, a filter and a reinfusion venous cannula. The venous drainage cannula is a 22 Fr cannula which has a balloon-inflatable, funnel-shaped distal tip and works as the inflow component of the circuit. This cannula is advanced into the venous system percutaneously through a 26 Fr sheath over a guidewire into the internal jugular or femoral vein. The centrifugal pump creates an adjustable suction force at the tip of the AngioVac venous cannula, resulting in venous drainage through the filter at an optimal rate of 3–5 L/min and removal of unwanted intravascular material. After filtration, the ‘purified’ blood is then returned to the venous system through a 16 Fr or greater reinfusion cannula placed into the internal jugular or femoral vein.^{5 14}

Since 2013, more use of the AngioVac aspiration system combined with lead extraction and prolonged course of antibiotics has shown promising data and success of CIED infections.^{11 15 16} This new novel modality of treatment is proving to be a good option for patients who are considered to be at a high perioperative risk and at a high risk of pulmonary embolism. In one study by Patel et al, the risk of septic pulmonary embolism for CIED-related endocarditis was shown to decrease with the use of Angiovac device-guided vegetation removal, followed by percutaneous lead extraction.¹⁵ The use of AngioVac-guided vegetation debulking has also shown to improve the efficacy of antibiotics in clearing the infection due to a decrease in the bacterial inoculum. This ultimately leads to decreased operative and perioperative mortality.¹⁶ Similar to our case with MSSA CIED, a few case reports have been published showing favourable outcomes with this method of treatment of CIED infections.¹⁶ The AngioVac system has also been used to remove pulmonary and right-heart thrombi. It has an advantage of the ability to remove the whole intact thrombus, thus reducing the need for preaspiration thrombolysis and pulmonary embolism.¹⁶

The most common complications associated with this procedure are bleeding, vegetation/thrombus fragmentation and distal embolisation, as well as atrial wall perforation, though exact incidence has not been described.¹⁷ Moreover, the advantages of being a less-invasive percutaneous procedure and avoiding the need for additional hardware outweigh these risks. Over the course of the years, many institutions and hospitals have adopted the use of AngioVac for vegetation debulking and percutaneous lead extraction and is turning out to be a safe and less-invasive alternative to open surgical thoracotomy.^{18 19}

Lead extraction is a high-risk and complex procedure which can have good outcomes with the right tools and multidisciplinary approach. A well-trained and experienced operator performing the procedure in a well-equipped setting with good staff is also critical. The use of a hybrid approach and AngioVac-assisted transvenous vegetation and lead removal decreases the risk of septic embolism and can be used in complex cases and high-risk surgical candidates.

AngioVac is used for extraction of intravascular materials such as vegetations and thrombi in high-risk surgical patients but is now being used for removal of lead related unwanted material as well. Due to the low incidence, reporting of such cases is important. Moreover, the use of AngioVac device to avoid surgical intervention in such cases is yet to be adopted widely. Our case endorses the use of the AngioVac system for lead-related vegetation extraction and shows the increased efficacy of simultaneous lead extraction resulting in prompt improvement in outcomes.

Patient’s perspective.

‘I am happy with the care provided in the hospital.’

Learning points.

• Cardiac implantable electronic devices vegetations larger than 20 mm have an increased risk of pulmonary embolism during percutaneous lead extraction, and open surgical removal is the ideal treatment approach.

• Adopting a multidisciplinary approach and deciding the treatment modality based on individual cases, even for vegetations larger than 20 mm, results in the best outcomes.

• AngioVac system consists of an extracorporeal filter which essentially removes the unwanted intravascular material (thrombi or vegetations) and returns the filtered blood back to the venous system, minimising blood loss.

• AngioVac-guided vegetation debulking improves the efficacy of antibiotics due to a decrease in the bacterial inoculum.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).