Mitral-Aortic Intervalvular Fibrosa Pseudoaneurysm

Abstract

Pseudoaneurysm of the mitral aortic intervalvular fibrosa (MAIVF-P) usually ensues as a complication of endocarditis or aortic valve surgery. When large, symptomatic or related to complications (rupture, compression of adjacent structures, embolic events, mitral regurgitation or heart failure) it warrants surgical excision. The natural course of uncomplicated/asymptomatic MAIVF-Ps is largely unknown since most patients are offered surgery. Increased surgical risk imposed by repeat operations in the majority of these patients is an important consideration and conservative treatment should not be excluded in selected cases. Herein we present two illustrative cases of MAIVF-P manifesting with significant arrhythmogenesis and complex endocarditis respectively. Both patients were managed conservatively. By briefly reviewing the existing literature, we discuss important diagnostic and therapeutic issues for MAIVF-Ps. To our knowledge complex ventricular arrhythmia has not been previously described as a prominent manifestation of MAIVF-P.

Keywords: Endocarditis; Mitral-aortic intervalvular fibrosa pseudoaneurysm; Pseudoaneurysm; Ventricular arrhythmia.

Fig. 1. Significant arrhythmogenesis caused by a mitral-aortic intervalvular fibrosa pseudoaneurysm (MAIVF-P). A: 24-hour Holter recording of the patient in case 1. PVCs of multiple morphologies are depicted. The electrophysiologic study confirmed that the majority of those were of left ventricular outflow tract origin. B: Transesophageal echocardiogram (TEE), long axis view of the aorta systolic frame. A MAIVF-P exhibiting systolic expansion is seen (asterisk). C: TEE, long axis view of the aorta, color Doppler interrogation. The MAIVF-P fills during systole (arrow). AV: aortic valve, LA: left atrium, LV: left ventricle.

Fig. 2. Multidetector computed tomography showing the mitral-aortic intervalvular fibrosa pseudoaneurysm (arrows) both in the sagittal plane (A) and in the axial plane (B).

Fig. 3. The gradual formation of a pseidoaneurysm. A: Transesophageal echocardiogram (TEE), long axis view of the aorta. A small echodense space representing an abscess is seen in the mitral-aortic inetrvalvular fibrosa area (arrowheads). B: TEE, long axis view of the aorta, four weeks later. A mitral aortic intervalvular fibrosa pseudoaneurysm (MAIVF-P) at the site of the preexisting abscess is now depicted (arrow). C: TEE, long axis view of the aorta, color Doppler interrogation. The MAIVF-P communicates with the left ventricular outflow tract and fills during systole (arrow). AV: aortic valve, LV: left ventricle, LA: left atrium.