Three-dimensional Transesophageal Echocardiographic Diagnosis of Catheter Endocarditis Hidden in Intracaval Stent.

In recent years, with an increasing number of central venous access procedures and cardiac implantable electronic device implantation, the incidence of infective endocarditis (IE) has become more prevalent. Two-dimensional transthoracic echocardiography (2D-TTE) and transesophageal echocardiography (TEE) are a key part of the evaluation of IE, but advances in three-dimensional echocardiography have enabled a better spatial resolution and visualization of cardiac structures, allowing the identification of any valvular vegetations, abscesses, or nodules. Herein, we report the usefulness of 3D-TEE in a difficult diagnosis of hemodialysis catheter endocarditis hidden in intracaval stent.

INTRODUCTION

In recent years, the increased rates of cardiac implantable electronic device (CIED) implantation and central venous access procedures have set the stage for higher rates of infection and the increasing frequency of infective endocarditis (IE).

Two-dimensional transthoracic echocardiography (2D-TTE) and transesophageal echocardiography (TEE) are a key part of the evaluation of IE, but advances in 3D echocardiography have enabled a better spatial resolution and visualization of cardiac structures, allowing the identification of any valvular vegetations, abscesses, or nodules.[1]

Herein, we report the usefulness of 3D-TEE in a difficult diagnosis of catheter endocarditis hidden in intracaval stent.

CASE REPORT

We report the case of a 77-year-old female patient with a clinical history of paroxysmal atrial fibrillation in treatment with oral anticoagulant therapy, ischemic heart disease, obesity type I, diabetes mellitus type II, and chronic kidney disease.

In March 2013, she was hospitalized at the Gynecology Department due to ovarian cancer.

During hospitalization, due to worsening of kidney function, the patient performed hemodialysis treatment through tunneled central venous catheter (CVC) (13.5 Fr × 24 cm) in the right internal jugular vein.

In May 2015, she underwent percutaneous transluminal angioplasty and stenting of superior vena cava (SVC) for a thrombosis caused by CVC.

During one of these hemodialysis sessions, fever started to rise to 39.8°C, and a purulent-hematic material began to come out from the tunneling of the CVC. She had a neutrophil leukocytosis (15.85 × 103/μL) and an increased C-reactive protein (176 mg/L).

After obtaining informed consent, the patient performed the 2D-TTE which showed the presence of a rounded hyperechogenic mass (diameter 35 mm × 35 mm) at the right atrium roof likely referred to the stent and the CVC coming from the SVC [Figure 1].

Figure 1

Two-dimensional transthoracic echocardiography: apical 4-chamber view in systolic phase showing a rounded hyperechogenic mass (diameter 35 mm × 35 mm) of uncertain diagnosis at the right atrium roof (arrow)

The TEE examination confirmed the diagnosis of the hemodialysis CVC hidden in the SVC stent since it raised from the SVC [Figure 2].

Figure 2

Transesophageal echocardiography: 5-chamber view in systolic phase showing hemodialysis central venous catheter hidden in the intracaval stent (arrow) in the right atrium, rising from the superior vena cava

At the end, 3D-TEE was the really useful diagnostic tool showing the scaffold of the SVC stent partially dislocated in the right atrium [Figure 3]. The hemodialysis CVC, placed inside the SVC stent, showed irregular and augmented thickness (14 mm) of its surface referable to endocarditis vegetations [Figure 4]. Therefore, three hemocultures were performed from CVC and resulted positive for Staphylococcus aureus.

Figure 3

Three-dimensional transesophageal echocardiography: long axis view acquired around 105° showing the scaffold of the superior vena cava stent, partially dislocated in the right atrium, in which was placed the hemodialysis central venous catheter (arrow). RA = Right atrium

Figure 4

Three-dimensional transesophageal echocardiography: 4 chamber view acquired at 0° showing hemodialysis central venous catheter, placed inside the superior vena cava stent with an irregular and augmented thickness (14 mm) of its surface (arrow) referable to endocarditis vegetation. RV = Right ventricle; LA = Left atrium; LV = Left ventricle

The patient was treated with antibiotic therapy (daptomycin and piperacillin/tazobactam) and after 4 weeks of treatment, she underwent CVC extraction.

DISCUSSION

In this case report, we describe the useful role of 3D-TEE in the diagnosis of endocarditis vegetations on CVC hidden in an SVC stent.

In recent years, with an increasing number of central venous access procedures in oncology, renal failure, and nutrition, the incidence of infection of CVC has become more prevalent.[2]

Concerning the CVCs for hemodialysis, they are placed percutaneously into a large central vein, internal jugular, or subclavian vein, through the SVC with the goal of placing the tips of the catheter at the junction of the SVC and the right atrium.

CVCs afford the luxury of immediate access to the circulation without the requirement for cannulation; however, these devices are plagued by their propensity for infection and thrombosis, like in this case.

In this regard, IE may involve heart valves (native valve endocarditis), prosthetic valves (prosthetic valve endocarditis), and implanted devices[34] and it is often deadly disease.[567]

The increased rates of CIED implantation and central venous access procedures, in older patients, with more comorbidities, have set the stage for higher rates of infection and the increasing frequency of IE in these patients.[8]

As in other forms of IE, echocardiography and blood cultures are the cornerstones of diagnosis.

Concerning the role of imaging, TEE may be useful in revealing catheters endocarditis and CIED infection in adults. Due to its poor sensitivity, TTE is frequently not helpful in ruling out a diagnosis of lead-related endocarditis, particularly in adults.[91011] Vilacosta et al.[12] confirmed the superiority of TEE in the diagnosis of lead-dependent IE (LDIE).

The recent advent of 3D imaging has considerably enhanced TEE by providing relatively high image quality and several unique views, and by its capability to assess accurately intracardiac masses[131415] and show intuitively understandable 3D images to physicians notspecialized in imaging.[16]

Indeed, in this case report, 3D-TEE allowed the diagnosis of vegetations on intracaval stent catheter in the right atrium. A prior visualization by X-plane allows the contemporary visualization of two orthogonal planes with high frame rate and is very useful in detecting hidden vegetations on devices. In this particular case, the 3D reconstruction gave good information on the characteristics of vegetation, despite the low frame rate.

However, the evaluation of patients with IE and LDIE include several other imaging techniques[3] such as multislice computed tomography, magnetic resonance imaging, 18F-fluorodeoxyglucose positron emission tomography/computed tomography, or other functional imaging modalities[16] that were not necessary in this case.

CONCLUSION

Three-dimensional echocardiography is an important tool for aiding diagnosis or for fine-tuning a suspected diagnosis when traditional echocardiography is not completely clear for both medical and surgical decision-making.

In fact, in this case, 3D-TEE was useful for better detection of the relationship between the vascular stent and hemodialysis CVC and for diagnosis of endocarditis vegetations on CVC.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.