Hypertrophic Cardiomyopathy and Outflow Tract Obstruction

To the Editor: In the article by Maron et al. (Jan. 23 issue) 1 about the effect of left ventricular outflow tract obstruction on the clinical outcome in hypertrophic cardiomyopathy, the authors conclude that patients with obstructive hypertrophic cardiomyopathy have a higher risk of death from cardiovascular causes, stroke, or sudden death than do patients without obstruction. They also suggest that over a low threshold of 30 mm Hg, the magnitude of the gradient does not add any prognostic information. Does this mean that a patient with a gradient of 40 mm Hg has the same risk as a patient with . . .