DIFFERENCES IN MYOCARDIAL VELOCITY-GRADIENT MEASURED THROUGHOUT THE CARDIAC CYCLE IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY, ATHLETES AND PATIENTS WITH LEFT-VENTRICULAR HYPERTROPHY DUE TO HYPERTENSION

Objectives. We sought to compare the myocardial velocity gradient (MVG ) measured across the left ventricular (LV) posterior wall during the cardiac cycle between patients with hypertrophic cardiomyopathy (HCM), athletes and patients with LV hypertrophy due to systemic hypertensio n and to determine whether it might be used to discriminate these grou ps. Background. The MVG is a new ultrasound variable, based on the col or Doppler technique, that quantifies the spatial distribution of tran smyocardial velocities. Methods. A cohort of 158 subjects was subdivid ed by age into two groups: Group I (mean [+/-SD] 30 +/- 7 years) and G roup II (58 +/- 8 years). Within each group there were three categorie s of subjects: Group la consisted of patients with HCM (n = 25), Group Ib consisted of athletes (n = 21), and Group Ic consisted of normal s ubjects; Group IIa consisted of patients with HCM (n = 19), Group IIb consisted of hypertensive patients (n = 27), and Group IIc consisted o f normal subjects (n = 33). Results. The MVG (mean [+/-SD] s(-1)) meas ured in systole was lower (p < 0.01) in patients with HCM (Group Ia 3. 2 +/- 1.1; Group IIa 2.9 +/- 1.2) compared with athletes (Group Ib 4.6 +/- 1.1), hypertensive patients (Group IIb 4.2 +/- 1.8) and normal su bjects (Group Ic 4.4 +/- 0.8; Group Ile 4.8 +/- 0.8), In early diastol e, the MVG was lower (p < 0.05) in patients with HCM (Group Ia 3.7 +/- 1.5; Group IIa 2.6 +/- 0.9) than in athletes (Group Ib 9.9 +/- 1.9) a nd normal subjects (Group Ic 9.2 +/- 2.0; Group IIc 3.6 +/- 1.5), but not hypertensive patients (Group IIb 3.3 +/- 1.3), In fate diastole, t he MVG in patients with HCM (Group Ia 1.3 +/- 0.8; Group IIa 1.4 +/- 0 .8) was lower (p < 0.01) than that in hypertensive patients (Group IIb 4.3 +/- 1.7) and normal subjects (Group IIc 3.5 +/- 0.9), An MVG less than or equal to 7 s(-1), as a single diagnostic approach, differenti ated accurately (0.96 positive and 0.94 negative predictive value) bet ween patients with HCM and athletes when the measurements were taken d uring early diastole. Conclusions. In both age groups, the MVG was low er in both systole and diastole in patients with HCM than in athletes, hypertensive patients or normal subjects, The MVG measured in early d iastole in a group of subjects 18 to 45 years old would appear to be a n accurate variable used to discriminate between HCM and hypertrophy i n athletes. (C) 1997 by the American College of Cardiology.