Surgical Treatment of Left Atrioventricular Fistula due to Mitral Annular Abscess after Mitral Valve Replacement for Active Endocarditis

Case Report

Ann Surg Perioper Care. 2017; 2(2): 1027.

Surgical Treatment of Left Atrioventricular Fistula due to Mitral Annular Abscess after Mitral Valve Replacement for Active Endocarditis

Nakanishi K*, Tambara K and Saito Y

Department of Cardiovascular Surgery, Juntendo University, Shizuoka Hospital, Shizuoka, Japan

*Corresponding author: Keisuke Nakanishi, Department of Cardiovascular Surgery, Juntendo University Shizuoka Hospital, 1129 Nagaoka, Izunokunishi, Shizuoka, Japan

Received: May 04, 2017; Accepted: May 26, 2017; Published: June 02, 2017

Abstract

Mitral valve annular abscess with fistula is a life-threatening complication of mitral valve endocarditis. Surgical treatment is yet to be established, and operative mortality rate remains high. In the present case, severe mitral regurgitation due to left ventricular atrium fistula was diagnosed using echocardiography 3 months after the patient underwent mitral valve replacement for active mitral valve endocarditis. The fistula was found at the posterior site of the mitral valve annulus. Severe destruction of the annulus had caused the prosthetic valve to become unstable. Surgical procedures involved resection of weakened tissue of the annulus, fistula closure with a bovine pericardial patch using 5-0 Prolene suture, and mitral valve re-replacement. The postoperative course was good, without any complication. This case report demonstrates that patch closure using a bovine patch and re-replacement of the mitral valve was feasible for the rare mitral valve annulus complication.

Keywords: Mitral annular abscess; Endocarditis; Left atrioventricular fistula; Cardiac surgery

Introduction

Mitral annular abscess is a rare complication of infective endocarditis, which could lead to life-threatening complications such as annular rupture or fistula formation. Extension of infective endocarditis beyond the valve annulus is associated with a higher mortality rate, cardiac heart failure, and the need for surgical intervention [1]. Annular extension of infective endocarditis causes annular enlargement pseudoaneurysm, and atrioventricular block [2]. Herein, we report a successful surgical treatment for peri-annular fistula due to infective endocarditis.

Case Presentation

A 46-year-old male underwent mitral valve replacement for endocarditis of the mitral valve. During the operation, mitral valve destruction was found to be severe; thus, valve replacement was decided. In the first operation, left ventricular perforation occurred from below the annulus to the intra-atrial wall, which was covered by a pericardial patch. Three months after the operation, the patient was febrile, hada blood pressure of 80/60mmHg, and hada low-volume pulse at a rate of 130/min. Chest examination disclosed bilateral diffuse fine crackles. Cardiovascular examination revealed a loud and harsh grade 5/6 pan systolic murmur at the apex, with radiation to the axilla, and a third heart sound. Electrocardiography revealed sinus tachycardia with features indicative of left atrial overload. Chest radiography (posterior anterior view) showed bilateral diffuse edema of the lung, and pleural effusion was suspected. Two-dimensional transthoracic echocardiography (apical four-chamber view) revealed a severe mitral regurgitation jet coming from the perforation and an echo-free cavity at the medial mitral annulus, with a 3mm perforated opening into the left atrium (Figure 1). No evidence of vegetation, thrombus, or other significant structural abnormalities was found. Blood culture from the patient showed no growth, although the past culture had revealed Staphylococcus epidermidis.

Citation: Nakanishi K, Tambara K and Saito Y. Surgical Treatment of Left Atrioventricular Fistula due to Mitral Annular Abscess after Mitral Valve Replacement for Active Endocarditis. Ann Surg Perioper Care. 2017; 2(2): 1027. ISSN:2573-5314