Infective Endocarditis With the Billowing Mitral Leaflet Syndrome

Abstract

SESSION TITLE: Global Case Report Poster - Miscellaneous SESSION TYPE: Global Case Report Poster PRESENTED ON: Tuesday, October 25, 2016 at 01:30 PM - 02:30 PM INTRODUCTION: Billowing mitral leaflet syndrome, one of the degenerative mitral valve diseases, is the cause of mitral regurgitation. Valvular heart disease predispose to infective endocarditis. In this case, bulky and redundant mitral leaflets of the billowing mitral leaflet syndrome became misunderstood as sessile vegetation. CASE PRESENTATION: A 52-year-old Japanease man presented with a 1-month history of fever, general malaise, edema of legs and low back pain. He had no significant medical history. We performed transthoracic echocardiography, and detected sessile vegetations, below 10mm in size, on the posterior mitral valve leaflets (P2) and anterior mitral valve leaflet (A2). In addition, echocardiography showed a mitral severe regurgitation caused by the posterior mitral valve leaflet (P2) prolapse. A definitive blood culture revealed the presence of streptococci mutans. Based on the above findings, we diagnosed infective endocarditis with relatively large sessile vegetation. The patient was started on a 2-week course of intravenous antibiotics, benzylpenicillin + gentamicin after Sulbactam / Ampicillin + gentamicin. But clinical response was not good, persistent sessile vegetation and constant high C-reactive protein level. Thereby, we planned mitral valve operation. Surgery was performed with cardiopulmonary bypass and mild hypothermia after achievement of general anesthesia. There was no sessile vegetation that pointed by preoperative echocardiography, but mitral valve leaflets were billowing with excess tissue. In addition, there were granular vegetations on bi-mitral valve leaflets, and P2 chordae was ruptured. Hence, infected bi-Mitral valve were resected, we operated mitral valve replacement by a mechanical valve. Ampicillin was administered for 6-weeks after surgery. Control of infection after operation was satisfactory. The patient discharged hospital on 42-days after surgery. DISCUSSION: Degenerative mitral regurgitation such as billowing mitral leaflet syndrome is the most frequent etiology for severe mitral regurgitation. mitral regurgitation has the potential for causing infective endocarditis. In this case, an excess of myxomatous mitral tissue, characteristic of billowing mitral leaflet syndrome, was diagnosed with sessile vegetation, because he had no significant valvular disease history, systolic murmur or heart failure. CONCLUSIONS: In summary, we have reported infective endocarditis with the billowing mitral leaflet syndrome. An excess of myxomatous mitral tissue was misjudged sessile vegetations. Reference #1: Br Heart J. 1975 Mar;37(3):326-30. Infective endocarditis in the billowing mitral leaflet syndrome. Lachman AS, Bramwell-Jones DM, Lakier JB, Pocock WA, Barlow JB. DISCLOSURE: The following authors have nothing to disclose: Ayako Nagasawa No Product/Research Disclosure Information