CENTRALIZED ECHOCARDIOGRAM QUALITY-CONTROL IN A MULTICENTER STUDY OF REGRESSION OF LEFT-VENTRICULAR HYPERTROPHY IN HYPERTENSION

Objective To test the feasibility and utility of instituting centraliz ed echocardiographic quality control during a multicenter study of reg ression of left ventricular hypertrophy in hypertension. Design and me thods The LIVE (Left Ventricular Hypertrophy: Indapamide Versus Enalap ril) study is an ongoing multicenter, double-blind, controlled study o f regression of echocardiographic left ventricular mass index in hyper tensive patients with left ventricular hypertrophy (left ventricular m ass indexes >100 g/m(2) for women and >120 g/m(2) for men) treated for 1 year with 1.5 mg indapamide sustained-release coated tablets versus 20 mg enalapril. A centralized evaluation committee has validated a p restudy sample echocardiogram from each center, and is now reviewing a ll videotapes recorded during this study for quality control; final re sults will be based on a further randomized blinded analysis by this c entralized evaluation committee. Results Since December 1994, 878 pati ents have been preselected (videoechocardiographic recordings sent for assessment), 645 selected (videoechocardiographic recordings validate d), and 576 randomly allocated to treatment. After preliminary quality control, 27% (233) of baseline echocardiograms were rejected by our c entralized evaluation committee, and 22% (142) of postinclusion echoca rdiographic measurements had to be repeated, mainly because they were of poor echogenic quality. Analysis of approved baseline echocardiogra ms for the first 274 randomly allocated patients with digitized data s howed that there was a significant correlation between centralized eva luation committee and investigator calculations of left ventricular ma ss index (r=0.76, P< 0.001), with consistently higher values for inves tigator calculations, independently of level of left ventricular mass index (correlation between difference and mean of investigator and cen tralized evaluation committee measurements, r=0.08, P=0.28). The mean difference was 8 +/- 20 g/m(2) (P < 0.001). Conclusion Early results o f the LIVE study quality control showed that real-time 'live', central ized echocardiographic reading was not only feasible, but also useful for avoiding unquantifiable echocardiograms and overestimation of left ventricular mass index. Thus, real-time, centralized echocardiographi c quality control should be recommended for multicenter studies of reg ression of left ventricular hypertrophy. (C) 1998 Lippincott-Raven Pub lishers.