Case Study: An Unusual Cause of Lead-Related Endocarditis

Case Description

A 62-year-old male with a complex cardiac history, chest pain, and hypotension was brought in by paramedics to our emergency department. He received appropriate resuscitation efforts en route, and was immediately triaged and stabilized. Given the constellation of symptoms, imaging of the chest via chest x-ray (Figure 1) and vasculature via CT angiography was performed (Figure 2) after stabilization. A working diagnosis of pulmonary embolus was established. Immediate anticoagulation with heparin was initiated, per protocol at our institution.

Complicating the clinical picture, this patient had fevers and an elevated WBC count. Given the potential for sepsis, cultures of the urine and blood were obtained, and parenteral broad spectrum antibiotic therapy was initiated. 

Cardiac history included the diagnosis of sick sinus syndrome, established elsewhere, for which he had received a dual-chamber pacemaker in 1994. After initial implantation, he had two myocardial infarctions involving a sizeable portion of the left ventricle. Despite medical therapy and revascularization attempts, his left ventricular ejection fraction (LVEF) dropped and remained impaired at 25%. In 2005, the left-sided pacemaker system was abandoned by an outside operator, and a new dual-chamber ICD system was implanted on the right side, after capping the leads on the left system. 

Several days into the current hospitalization, blood cultures obtained during initial presentation grew fungus (Candida species). Standard transthoracic echocardiography was performed, and revealed an impaired LVEF at 25% and large mobile echo densities on the right ventricular ICD lead (Figure 3). There was a suggestion of tricuspid valve involvement, leading to a transesophageal echo. This further delineated the vegetation in terms of size and morphology, as well as lead attachment (Figure 4). Ultimately, dimensions of the vegetation were established at 3.4 cm x 2.2 cm. Given presentation with these now presumed septic pulmonary emboli and fungal vegetations, we were asked to assist in management of this complicated CIED-related infection. 

Lead extraction with complete removal of all intracardiac hardware was essential. However, sheer size and morphology of the vegetation made distal embolization into the pulmonary vasculature a real and potentially life-threatening complication. Formal consultation was made with our CT surgeons, and given comorbidities and frailty index, it was felt the patient was at high risk for hardware removal with a standard open-chest, on-pump approach.  

Our center is a high-volume extraction center, and given our experience with similar clinical situations, we felt a catheter-based “debulking” solution was a possibility in utilizing a relatively new and unique system for this application via the AngioVac System (AngioDynamics).  

After extensive coordination with our industry colleagues, as well as logistical planning with our CVOR, removal of the fungal vegetation with the AngioVac System was planned, followed by bilateral lead extraction.   

After obtaining bilateral femoral access for the inflow and outflow (suction) cannula, real-time TEE imaging was utilized to direct the cannula in direct contact with the vegetation on the lead. The cannula is not directly steerable; thus, under fluoroscopic guidance, the tip of the cannula was placed into the lower right atrium via the inferior vena cava. Using a gooseneck snare, the tip of the cannula was engaged and directed at the vegetation. The AngioVac System was enabled, and suction was directly applied to the vegetation (Figure 5). After applying suction, the removed fungal vegetation fragments can be seen in the system filter and externally (Figures 6 and 7). Immediate real-time TEE imaging after debulking can be seen (Figure 8). At this point, the vegetation was removed and debulked significantly, and we felt it was safe to proceed with lead extraction via the standard route bilaterally. Ultimately, all intracardiac hardware was removed uneventfully. The patient received 6 weeks of parenteral antifungal treatment while wearing a LifeVest (ZOLL Medical Corporation). Finally, after reviewing his pacing burden from device interrogation prior to system removal, it was essentially negligible. Given the high risk of recurrent infection, a subcutaneous ICD was implanted uneventfully. 

Discussion

Fungal endocarditis (FE), or more specifically, lead-related endocarditis (LRE), is an increasingly prevalent and devastating disease in today’s highly advancing medical practice.¹ With more patients receiving broad-spectrum antibiotics or invasive interventions, including long-term central venous catheters or prosthetic heart valve placements, FE is increasingly reported.² Recognizing FE early on can be difficult, because it often lacks some classic signs and symptoms found in bacterial endocarditis. Diagnosis can be further complicated by the difficulty of making FE meet the Duke criteria since blood cultures are often negative, despite vegetations demonstrated on echocardiography. More pointedly, a keen insight into this disease process as well as a higher index of suspicion in patients with implantable devices is a must. In patients with an implantable cardiac device and fungemia, systemic treatment with parenteral antifungal medications is the cornerstone of therapy to mitigate potential hemodynamic sequelae and septic shock.³ In the absence of significant lead involvement by standard imaging techniques, simple medical therapy can be considered.⁴ However, strong consideration should be given to complete removal of all intracardiac hardware to truly eliminate potentially recurrent fungemia, which has an associated increase in mortality.⁴

Lead extraction for the complete removal of leads in patients with infective, or so-called lead-related endocarditis, has an established safety record when performed by experienced operators at high-volume centers such as ours.⁵ Despite this, there remains very high-risk patients such as the one described here, in which removal of the lead may result in distal embolization into the vasculature and potential death if obstruction is significant enough. Surgery is traditionally offered as front-line therapy in patients with vegetations usually on the order of 2.5-3 cm in circumference and larger.⁶ Avoiding the morbidities of an open surgical approach is ideal in most patients, and we present here a novel technique that can be utilized to avoid surgery and lead to a successful complete system extraction utilizing current lead extraction approaches.

Disclosures: The authors have no conflicts of interest to report regarding the content herein.  

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2. Charlier C, Hart E, Lefort A, et al. Fluconazole for the management of invasive candidiasis: where do we stand after 15 years? J Antimicrob Chemother. 2006;57:384-410.
3. Pierrotti LC, Baddour LM. Fungal endocarditis, 1995-2000. Chest. 2002;122:302-310.
4. Mugge A, Daniel WG, Frank G, Lichtlen PR. Echocardiography in infective endocarditis: reassessment of prognostic implications of vegetation size determined by the transthoracic and the transesophageal approach. J Am Coll Cardiol. 1989;14:631-638.
5. Wilkoff BL, Love CJ, Byrd CL, et al. Transvenous lead extraction: Heart Rhythm Society expert consensus on facilities, training, indications, and patient management: this document was endorsed by the American Heart Association (AHA). Heart Rhythm. 2009;6:1085-1094.
6. Lead Extraction 2008: Critical Review and Implementation of HRS Guidelines; HR 2008 satellite symposium co-sponsored by Cleveland Clinic and Heart Rhythm Society, Course directors Bruce Wilkoff, Charles Love, Charles Byrd,May 15, 2008. San Francisco, CA.