title: When what appears to be mitral stenosis is not: diagnostic and therapeutic implications.
abstract: The authors report the case of a 53-year-old man, with a long-standing history of mild mitral stenosis, admitted for worsening fatigue. Transthoracic echocardiography (limited by poor image quality) showed mitral annular calcification, leaflets that were difficult to visualize and an estimated mitral valve area of 1.8 cm(2) by the pressure half-time method. However, elevated mean transmitral and right ventricle/right atrium gradients were identified (39 and 117 mmHg, respectively). This puzzling discrepancy in the echocardiographic findings prompted investigation by transesophageal echocardiography, which revealed an echogenic structure adjacent to the mitral annulus, causing severe obstruction (effective orifice area 0.7 cm(2)). The suspicion of supravalvular mitral ring was confirmed during surgery. Following ring resection and mitral valve replacement there was significant improvement in the patient's clinical condition and normalization of the left atrium/left ventricle gradient. Supravalvular mitral ring is an unusual cause of congenital mitral stenosis, characterized by an abnormal ridge of connective tissue on the atrial side of the mitral valve, which often obstructs mitral valve inflow. Few cases have been reported, most of them in children with concomitant congenital abnormalities. Diagnosis of a supravalvular mitral ring is challenging, since it is very difficult to visualize in most diagnostic tests. It was the combination of clinical and various echocardiographic findings that led us to suspect this very rare condition, enabling appropriate treatment, with excellent long-term results.
authors.affiliation: Serviço de Cardiologia do Hospital Geral, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. Electronic address: inesalm@gmail.com.
authors.forename: Inês
authors.initials: I
authors.lastname: Almeida
authors.affiliation: Serviço de Cardiologia do Hospital Geral, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Francisca
authors.initials: F
authors.lastname: Caetano
authors.affiliation: Serviço de Cardiologia do Hospital Geral, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Trigo
authors.affiliation: Serviço de Cardiologia do Hospital Geral, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Paula
authors.initials: P
authors.lastname: Mota
authors.affiliation: Serviço de Cardiologia do Hospital Geral, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Maria do Carmo
authors.initials: Mdo C
authors.lastname: Cachulo
authors.affiliation: Serviço de Cirurgia Cardiotorácica, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Manuel
authors.initials: M
authors.lastname: Antunes
authors.affiliation: Serviço de Cardiologia do Hospital Geral, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Leitão Marques
mesh_terms: D003951:Diagnostic Errors; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000002:abnormalities* / Q000601:surgery; D008946:Mitral Valve Stenosis / Q000175:diagnosis* / Q000209:etiology*
keywords: Anel mitral supravalvular; Anel supramitral; Congenital mitral stenosis; Estenose mitral; Estenose mitral congénita; Estenose mitral supravalvular; Mitral stenosis; Supravalvular mitral ring; Supravalvular mitral stenosis; Supravalvular ring