Palka P, Lange A, Fleming AD, Fenn LN, Shaw TRD, Starkey IR, Fox KAA, McDicken WN, Sutherland GR. Assessment of transmural velocity gradients in hypertrophic hearts-A new diagnostic index for hypetrophic cardiomyopathy. J Am Coll Cardiol. 1996 Feb 1;27(2_supplement_1):21.