Muscular Mitral Chord Contribution to Left Ventricular Outflow Tract Obstruction in HOCM

Papillary muscle anomaly with a muscular chord directly attached to the anterior mitral leaflet is a rare mitral valve disease. A 62-year-old man with systolic anterior motion of the anterior mitral leaflet and hypertrophic obstructive cardiomyopathy presented to surgical intervention after unsuccessful transcoronary ablation of septal hypertrophy with alcohol. Intraoperative findings revealed a primarily not detected anomalous muscular mitral chord (0.8 × 2.2 cm) connecting the base of the A1 segment to the anterolateral papillary muscle. Resection of this chord and additional septal myectomy treated systolic anterior motion and obstruction of the outflow tract. In spite of the infrequent occurrence, anomalies of the subvalvular apparatus, such as muscular chords, should be ruled out by thorough transesophageal echocardiography imaging before decision on the therapeutical strategy.