Intracardiac fistula due to prosthetic aortic valve abscess causing acute heart failure

Abstract

A 78-year-old male patient was admitted with symptoms of acute heart failure. Seven months ago he had undergone replacement of a calcified aortic valve with a pericardial stented bioprosthesis. The patient denied fever at initial presentation, but systemic inflammation parameters were slightly elevated with a C-reactive protein of 18 mg/L and white cell count of 13.3 9 10 /L. Physical examination revealed a systolic murmur at the apex with radiation to the left axilla. Transthoracic echocardiography showed normal sized left ventricle with a mildly reduced systolic function. Color Doppler imaging showed an eccentric jet along the posterior-lateral atrial wall in the apical four chamber view, suggesting a severe mitral regurgitation (Fig. 1a, online movie clip 1). Furthermore, a paravalvular space between the prosthetic valve and the left atrium was found in the three chamber view (Fig. 1b [arrow], online movie clip 2). The transesophageal echocardiography (TEE) confirmed only mild mitral regurgitation. However, a large paravalvular abscess was observed (14 9 44 mm, Fig. 1f) with a fistula into the left atrium (Fig. 1c [arrow], online movie clip 3). Color Doppler echocardiography revealed a holosystolic shunt from the left ventricular outflow tract (LVOT) to the left atrium (Fig. 1d, e, online movie clip 4). The eccentric jet shape misleadingly indicated severe mitral regurgitation on the transthoracic approach. The hemodynamic consequence of this intracardiac fistula was similar to that of acute mitral regurgitation causing acute heart failure. An E/E0 ratio of 36 was suggestive of acute volume load on the left ventricle. This was emphasized by an elevated mean trans-mitral gradient of 3 mmHg due to the high shunt volume. Streptococcus thermophilus was detected in blood culture and C-reactive protein raised to 130 mg/L, white cell count to 22 9 10 /L and procalcitonin to 4.2 ng/mL. Progressive hemodynamic deterioration and refractory pulmonary edema precluded surgery for prosthetic valve endocarditis complicated by intracardiac fistula. Given the critical hemodynamic and clinical situation since admission there were no reasonable alternative treatment options. Unfortunately, the patient died few days later in cardiogenic-septic shock. Paravalvular abscess is a serious and often rapid growing complication of endocarditis with high mortality [1, 2]. Intracardiac fistula formation due to infective endocarditis is a rare complication, with an incidence of 1.6 up to 3.5 % in patients with prosthetic valve endocarditis [3]. Recently, a fatal case of prosthetic valve endocarditis after transcatheter valve implantation (TAVI) with an intracardiac fistula from the LVOT to the left atrium has been also reported [4]. In this context, cardiac surgery is indicated if fistula, valve destruction or severe prosthetic valve dysfunction occurs [1, 5]. However, prosthetic valve endocarditis and severe aortic root destruction are risk factors for early mortality [6]. A fistula from the LVOT into the left atrium implicates a volume overload of the left ventricle with the risk of backward heart failure and pulmonary edema. When acute heart failure occurs in patients with previous cardiac surgery and implanted prosthetic material, an endocarditis has generally to be considered. Normal findings at regularly follow-up echocardiography after valve replacement may not exclude the occurence of such a rare but catastrophic event. Here, the Electronic supplementary material The online version of this article (doi:10.1007/s00392-013-0573-2) contains supplementary material, which is available to authorized users.