Brief Case Description

The patient was a 79 year-old female with a past medical history of rheumatic fever who had undergone aortic and mitral valve replacement with biological valves and tricuspid valve repair with a prosthetic ring four years earlier. She also had a permanent pacemaker. She undwerwent partial colectomy for diverticulitis two years after her valve surgery. A few weeks after this procedure, she presented with fever and chills.

Blood cultures were positive with Enterococcus faecalis. Transthoracic and transesophageal echocardiography (TEE) suggested the presence of vegetations on the bioprosthetic mitral valve and the pacemaker lead. She was treated with appropriate antibiotics for a total of 6 weeks. A few weeks later, she presented with low grade fever and fatigue which persisted despite a second run of intravenous antibiotics. Blood cultures were positive with the same organism.

Transesophageal Echocardiography

A repeat transthoracic and transesophageal echocardiography suggested the presence of vegetations on the ventricular aspect of one of the mitral bioprosthetic cusps and showed vegetations on the pacemaker lead. There was no annular abscess. There was at least moderate mitral regurgitation.The aortic and tricuspid valves appeared intact.

The patient was diagnosed with subacute prosthetic valve endocarditis and pacemaker lead infection and referred for surgical treatment.

Surgical intervention was indicated because of persistence of infection and positive blood cultures despite appropriate antibiotic treatment.

Intraoperative 2D and 3D Echocardiography

Intraoperative transesophageal echocardiography could not rule out with certainty the existence of vegetations on the ventricular aspect of the mitral bioprosthetic valve. A three dimensional echocardiography was performed and showed the thickening and retraction of one of the cusps of the mitral bioprosthetic valve. The atrial and ventricular views of the mitral bioprosthetic valve did not show any vegetations. 3D echocardiography showed with extreme precision the location and severity of mitral regurgitation.

Atrial View

Ventricular View

Jet of Mitral Regurgitation View

 

 

 

Operative Procedure

Valve Analysis

The inspection of the mitral bioprosthetic valve showed the abrasion of one of the leaflets which was also thickened and slightly retracted. There were no vegetations. The valve was well-seated with no sign of annular involvement. These findings were compatible with a healed infective endocarditis.

The inspection of the aortic bioprosthesis showed a normal appearing valve.

There were several vegetations on the pacemaker lead which was laying in contact with the endothelialized tricuspid ring. There were no direct signs of tricuspid ring infection.

Surgical Management

The mitral bioprosthetic valve was completely removed. We also removed entirely the pacemaker and the tricuspid ring. Several specimens were sent for bacteriology.

The patient underwent a reoperative mitral valve replacement with a biological valve and tricuspid valve repair with a prosthetic ring.

Postoperative Care

Postoperative course was uneventful. The patient had an underline sinus rhythm and did not require the insertion of another pacemaker.

The culture of mitral bioprosthesis did not show any growth. The pacemaker lead and the tricuspid ring were infected with Enterococcus faecalis. The patient was discharged with long-term antibiotic therapy.

Predischarge echocardiography showed well-functioning bioprosthetic valves in the aortic and mitral positions. The tricuspid valve was competent.

For more information refer to Current Status >> Infective Endocarditis Section