Mitral regurgitation secondary to ruptured chordae tendineae: clinical, hemodynamic and electrocardiographic findings.

The clinical, hemodynamic, and electrocardiographic findings in 11 patients with mitral regurgitation secondary to ruptured chordae tendineae are presented. Left atrial overloading, as manifested by a large terminal negative force in the P wave of lead V1, was present in 8 of the 11 patients. Six of the eight patients with this atrial abnormality had a normal size or minimally enlarged left atrium on chest x-ray films and angiography. Left ventricular hypertrohpy was present in 7 of the 11 patients and appeared to be related to the duration of cardiac symptoms. It is concluded that a large terminal negative force in the P wave in lead V1 is a useful clinical indicator of increased left atrial pressure in mitral regurgitation of recent onset. The electrocardiographic finding of left atrial overloading is to be expected in most cases of mitral regurgitation secondary to rupture of the chordae tendineae.