Left ventricular (LV) ejection fraction is normal in most patients with uncomplicated hypertension, but the prevalence and correlates of decreased LV systolic chamber and myocardial function, as assessed by midwall mechanics, in hypertensive patients identified as being at high risk by the presence of LV hypertrophy on the electrocardiogram has not been established. Therefore echocardiograms were obtained in 913 patients with stage I to III hypertension and LV hypertrophy determined by electrocardiographic (Cornell voltage duration or Sokolow-Lyon voltage) criteria after 14 days' placebo treatment. The 913 patients' mean age was 66 years, and 42% were women. Fourteen percent had subnormal LV endocardial shortening, 24% had subnormal midwall shortening, and 13% had reduced stress-corrected midwall shortening. Nineteen percent had normal LV geometry, 11% had concentric remodeling, 47% had eccentric hypertrophy, and 23% had concentric hypertrophy. LV systolic performance evaluated by LV endocardial shortening and midwall shortening was impaired in 10% of patients with normal geometry, 20% with concentric remodeling, 27% with eccentric hypertrophy, and 42% with concentric hypertrophy. Relative wall thickness, an important independent correlate of LV chamber function, was related directly to endocardial shortening and negatively to midwall shortening and stress-corrected midwall shortening. LV mass was the strongest independent correlate of impaired endocardial shortening, midwall shortening, or both. In hypertensive patients with electrocardiographic LV hypertrophy, indexes of systolic performance are subnormal in 10% to 42% with different LV geometric patterns. Depressed endocardial shortening is most common in patients with eccentric LV hypertrophy, whereas impaired midwall shortening is most prevalent in patients with concentric remodeling or hypertrophy. Thus, in hypertensive patients with electrocardiographic LV hypertrophy, impaired LV performance occurs most often, and is associated with greater LV mass and relative wall thickness and may contribute to the high rate of cardiovascular events.