[The mitral valve chordal system as a cause of innocuous heart murmur]

To specify the role of morphofunctional features of mitral chorda in forming innocent cardiac murmur (ICM), 107 and 20 young men with or without ICM, respectively, were examined clinically and instrumentally at rest, muscular load and hyperventilation. Echocardiography was recorded in one-dimentional, sectoral and Doppler regimens. Fluttering chorda (FC) of the mitral valve (MV) manifesting by hyperkinesia of usually fixed MV chorda, its early systolic dislocation into the left ventricular outflow tract was registered in 34.5% of ICM patients, 11.2% of them had echocardiographic evidence of the chordal shift in the systole into the above tract. In ICM-free subjects the phenomenon FC and the systolic chordal shift were absent (the difference was significant, p < 0.05). The FC phenomenon is attributed to local dysfunction of the papillary muscles and may produce distinct labile nonregurgitation systolic murmur.