[Phono-mechanographic surveys of a patient with Björk mitral valve prosthesis and complete atrio-ventricular block (author's transl)].

A study of a patient with Björk-Shiley mitral valve prosthesis and complete artrio-ventricular block recorded the presystolic valve closure with -r intervals equal to or higher than 290 m.sec. After applying a permanent pacemaker, closure of the prosthesis of the presystole occurred when the atrial systole preceeded the spike by at least 190 m.sec. This survey demonstrates that the atrial systole can provoke, by itself, the closure of the mitralic valve.