Introduction

In the early 21st century, infective endocarditis (IE) is more often an acute disease and mortality remains relatively high (1). Although infective endocarditis is primarily treated conservatively with antimicrobial therapy, early surgical intervention is often mandatory when various complications arise. These include large mobile vegetations. Optimal timing of surgical intervention in patients with infected heart valves results in reduced early and late mortality (2). Some complications may swing the argument in favour of surgery: systemic embolisms with persistent, large and mobile vegetative lesions (3).

Case Presentation

Our case was a 43-year-old male. He had been diagnosed as having severe aortic regurgitation and surgical repair had been recommended a year ago. But he refused the operation and he was followed with medical therapy by another institution. He was suffering from shortness of breath, palpitation, weight loss and fever; worsening since last month. Transthoracic and transesophageal echocardiography showed severe aortic and mitral regurgitation as well as a mobile vegetative mass of 6x4 mm on anterior leaflet of mitral valve and two different mobile vegetative masses of 10x4 mm and 10x3 mm on aortic valve (Figures 1&2).

Figure 1

Figure 1

Figure 2

Figure 2

Moreover, left ventricular end-diastolic and end-systolic diameters were measured as 64 and 47 mm, respectively. Pulmonary arterial pressure was 30 mm Hg and left ventricular ejection fraction was calculated as 60%. Since there were mobile vegetative masses and no findings of myocardial ischemia, coronary angiography was not planned. After consultation with Department of Infectious Diseases, parenteral treatment of vancomycin HCl of 1 g bid and amikacin sulphate of 500 mg bid was started. Emergent surgical intervention was planned due to many vegetative masses.

He was operated under endotracheal general anesthesia and in supine position.Following a median sternotomy,pericardium was opened longitudinally. After heparinization, extra-corporeal circulation was established between the venae cavae and the ascending aorta. A cross clamp was placed on aorta and by antegrade intermittent selective plus retrograde isothermic blood cardioplegia,cardiac arrest was established.Hypothermia was moderate (28ºc).A vent was placed via the right superior pulmonary vein. Standard aortotomy was made. Two vegetative masses were explored on the native valve (Figure 3).

Figure 3

Figure 3

Native aortic valve was resected.

Standard left atriotomy was made from interatrial groove. A vegetative mass was explored on the mitral valve (Figure 4).

Figure 4

Figure 4

We performed a MVR (29 no ATS bileaflet mechanical valve) and an AVR (23 no St Jude bileaflet mechanical valve) with separate sutures. No additional problem was seen postoperatively and he was discharged on 8^th postoperative day with surgical cure. No microorganismal growth was detected in intra- and postoperative hemocultures and operative specimens. After his discharge, parenteral antibiotherapy was continued 4 more weeks after addition of cephtriaxone of 1 g bid. Postoperatively on the day of discharge day and after 3 months an echocardiographic investigation revealed. He is still symptom-free and the valve functions are good in control TTE.

Discussion

Bacterial endocarditis of the mitral valve appears to be much less common than bacterial endocarditis of the aortic valve. The surgical anatomy of the lesions is described: vegetations, perforations, rupture of chordae tendinae, abscess of the mitral ring observed in the isolated mitral endocarditis, mitral-aortic dislocation, abscesses and aneurysms of the mitral-aortic fibrosa and jet lesions on the anterior mitral leaflet. In a personal series, the authors recorded a mortality of 12% in isolated mitral cases and 42% in the combined mitral-aortic patients (4).

In a cohort study; 2781 adults with definite IE who were admitted to 58 hospitals in 25 countries. The median age of the cohort was 57.9 (interquartile range, 43.2-71.8) years, and 72.1% had native valve IE. Most patients (77.0%) presented early in the disease (<30 days) with few of the classic clinical hallmarks of IE. Staphylococcus aureus was the most common pathogen (31.2%). The mitral (41.1%) and aortic (37.6%) valves were infected most commonly. Surgical therapy was common (48.2%), and in-hospital mortality remained high (17.7%). Mitral valve vegetation was associated with an increased risk of in-hospital death, and surgery was associated with a decreased risk (1).

In the study of Ishikawa et al.; 40 adult patients who had undergone surgery. Thirty-three patients had native valve endocarditis (NVE). Diseased lesions were located in the mitral valve (MV) in 21 patients, aortic valve in 15 and mitral plus aortic valves in four. Twenty-eight patients (70%) were operated on during the active phase of IE. Streptococcus, Staphylococcus and Enterococcus species were predominant in the bacterial examination. Active vegetation was observed in 26 (65%) patients (5).

In the study of Tamura; 34 of 40 patients with infective endocarditis had native valve endocarditis (NVE) . The aortic valve was involved most frequently (AV : 16, MV : 6, AV+MV : 8). The infecting organisms were identified by blood cultures in 26 patients. Bacteria and/or fungi were found histologically in 23 valves, even in those in which cultures of excised tissues were negative (6).

In conclusion; operative results of NVE were good after complete resection of infective sites including valve annulus (5). Mechanical prostheses represent a safe valve substitute in cases of acute native valve endocarditis. When radical resection of all the infected areas is performed, the incidence of endocarditis recurrence is acceptable (7). Early surgical treatment remains the most significant factor in decreasing the fatality of such lesions (4).