Introduction

Splenic infarcts and infective endocarditis are very complicated clinical entiety. Controversy exists regarding the proper selection, timing, and ^{order of surgical procedures offered to the patient with concomitant infective endocarditis and splenic infarcts or abscesses. Although that by Computed tomography (CT) sometimes can not be made difference between splenic infarct and abscess, it is the diagnostic step for identifying extracardiac infectious sources, including splenic lesions. In clinically stable patient is recommended firstly to be performed splenectomy and then, after all infectious sources are liquidated can be performed valve surgery. When patient with infectious endocarditis presents with rapidly progressing acute heart failure the optimal choice is one-stage valve replacement and splenectomy. We describe a patient with mitral valve endocarditis and heart failure, accompanied by infected splenic infarcts.}

Case report

A 69-year old woman with fatigue, fever, hemodynamic instability, heart failure. Two months before she was treated with i.m. gluteal injections for tingling in the knees. Then fever, fatigue and gluteal abscess occurred. Abscess was excised but the symptoms of infection persisted. She was admitted in infectious clinic where she developed heart failure ^{and was transferred to ICU with haemodynamic instability. From blood cultures grew Staphylococcus epidermidis MRSE. Transesophageal echocardiography showed mitral regurgitation III degree, myxomatous leaflets of the mitral valve with two big vegetations on the atrial side of the leaflets. Tricuspid regurgitation mild to moderate was shown and pulmonary hypertension 40 mmHg. Ejection fraction was 51%. CT demonstrated two big infarcts of the spleen – meazurment 50/60mm and 30/40mm, with the suspicious of splenic abscesses. The typical Roth spots for infective endocarditis were found on ophtalmoscopy. The operative mortality risk calculated by Euroscore was 57,53%.}

The patient was admitted at the operating room in urgent order. Using a general anesthesia and standard surgical preparation the heart was approached via median sternotomy and extracorporeal circulation was iniated using standart aortic and right atrial canulation. After cardioplegic arrest the mitral valve was exposed and two big vegetations on the anterior and posterior mitral leaflet from the atrial side of the mitral valve were detected, size at about 2/2,5cm each. Advanced erosion of the leaflets was shown too (Fig 1).

Figure 1

Fig 1. Thrombotic precipitation (arrow) to a valve leaflet (mitral valve). Van Gieson, x 32.

A mitral valve replacement with ATS mechanical valve prosthesis was performed. Tricuspid valve annuloplasty a modo Kay was performed. Then after sternal closure we performed splenectomy. Two splenic infarcts were detected at the superior and the inferior segment, with size respectively at about 5/6cm and 2/2,5cm (Fig 2).

Figure 2

Fig 2. Macroscopic view – spleen and two infarct areas in phase of organization (arrows).

At time of the splenic mobilization the bigger splenic infarct ruptured and infarct cavity revealed. Pathohistology showed infected splenic infarcts in phase of organization (Fig 3).

Figure 3

Fig 3. A border area – infected infarct and usual splenic parenchyma. HE, x 50.

After completion the operation, the patient was transferred into the ICU in stable condition and extubated on 3th postoperative day. Postoperative course was uneventful, the patient remained afebrile with negative blood cultures. Echocardiography showed good function of the heart valves and mitral prosthesis with good ventricular function. The patient was discharged on the 22-th postoperative ^{day. At first and sixth month following discharge patient presented with expected course of recovery, on echographyc examination and laboratory studies there were no signs of infection recurrence.}

Comment

Pathogenesis of infective endocarditis and splenic infarcts is well known. Splenic infarcts in infective endocarditis develop via splenic artery occlusion ^{by embolized vegetations, or by an embolus also originating from an infected valvular tissue [1]. CT and Magnetic Resonance Imaging (MRI) are the best methods to diagnose splenic lesions (abscesses and infarcts) [1]. They are the most sensitive and specific methods for this diagnosis [2]. There is an incidence of splenic infarction and abscess of 33% in patients with valve replacement for left side infective endocarditis [3]. CT or MRI should be performed to diagnose this pathology [2],[3]. With these methods can be made right notion for the number, size, localization of the splenic infarcts and any other infectious lesions in the abdomen.}

When splenic infarcts are diagnosed, splenectomy is a very important therapeutic step in infective endocarditis [3]. Eradication of all infectious sources and adequate antibiotic therapy is of paramount importance in surgically treated patients with infective endocarditis [1]. According to Ting and colleagues [3], patients with infective endocarditis ^{and splenic infarcts greater than 2cm and peripheral lesions, are indicated for splenectomy. In these patients the risk of splenic rupture is high [3],[4]. In patients with splenic lesions smaller than 2cm who are not subcapsular conservative treatment can be effective [3],[4]. Splenic tissue is fragile and rupture can result with a minimal trauma or spontaneously, especially if the lesions are located subcapsulary [3],[5]. The risk arises after valve replacement and the need for anticoagulation therapy [4].}

Progression of heart failure (CHF) worsens the prognosis in patients with infective endocarditis and is an indication for urgent surgical management [6]. It may develop acutely from perforation of a native ^{or bioprosthetic valve leaflet, rupture of infected mitral chordae, valve obstruction from bulky vegetations, or sudden intracardiac shunts from fistulous tracts or prosthetic dehiscence [1]. According to Baddour and colleagues [7] patients who have normal ventricular function or only mild CHF when IE is initially diagnosed may progress to severe CHF during treatment, and two thirds of these patients will do so within the first month of therapy. CHF in infective endocarditis portends a grave prognosis with medical therapy alone and also is the most powerful predictor of poor outcome with surgical therapy [7]. Delaying surgery for antibiotic treatment carries the risk of permanent ventricular dysfunction [1].}

In clinically stable patients splenectomy should be performed before ^{valve surgery because of the risk of infection to the valve prosthesis as a result of the bacteremia from the spleen [1], [2]. In clinically unstable patients (hemodynamic instability, threatening CHF), the optimal choice is one-stage valve surgery and splenectomy. In any patient, a decision to delay surgery to extend preoperative antibiotic treatment carries the risk of permanent ventricular dysfunction and should be discouraged [7]. The incidence of reinfection of newly implanted valves in patients with active IE has been estimated to be 2% to 3% far less than the mortality rate for uncontrolled CHF [7].}

Abdominal CT scan should be performed on regular basis in every patient with IE and suspected distal embolization. It is a powerful method for revealing infarcts and abscesses with any localization. In clinically unstable patients with proved big splenic infarcts and infective endocarditis, one-stage valve surgery and splenectomy is the optimal method of treatment. Eradication of all infectious sources in these patients is the key of success.