Mid-systolic septal deceleration. A new sign of left ventricular outflow tract obstruction obtained by color-coded tissue Doppler echocardiography.

Hypertrophic obstructive cardiomyopathy (HOCM) is characterized by the presence of a dynamic left ventricular outflow tract gradient. We studied septal longitudinal motion by color coded tissue Doppler echocardiography in a 69-year old HOCM patient during and after catheter based treatment by trans coronary alcohol ablation of septal hypertrophy. The presence of dynamic left ventricular outflow tract obstruction was associated with a characteristic abrupt mid-systolic septal deceleration pattern in the tissue Doppler velocity trace. Five weeks after treatment, this pattern was no longer visible at rest.