The multiple dipole electrical source method diagnosed increased left ventricular muscle weight with 98% sensitivity and 84% specificity, correlating strongly with angiographic measurements (r2=86%).
Observational (n=72)
Effect estimate: r2 86%
Using the method previously described, the time-varying strengths of 12 dipoles (representing the depolarization of the ventricles) were calculated from body surface potential measurements. Dipole activities (DA) were obtained for each dipole by time integration of its strength. Seventy-two patients with angiographically determined left ventricular muscle weight (LVMW) were studied. Fifty-two of 53 patients with increased LVMW had increased DA in the left ventricle and septum (LVSDA). Thus, diagnostic sensitivity was 98%. Sixteen of 19 patients with normal LVMW had normal LVSDA (specificity, 84%). The correlation between LVSDA and LVMW was r 2 =86%, and the standard error of the LVMW estimate ( see ) was±49 g. A subgroup with pure left ventricular hypertrophy (LVH) consisting of 27 patients over 25 years of age with isolated aortic valve disease was studied separately. The correlation between LVSDA and LVMW was r 2 =92% and see was ±31 g. After correcting for the uncertainty in the angiographic LVMW measurements, the see for the complete group was reduced to ±37 g. The diagnosis and quantitation of LVH with this method was considerably better than with conventional electrocardiography or vectorcardiography.
Holt et al. (Sat,) conducted a observational in Left ventricular hypertrophy (n=72). Multiple dipole electrical source method vs. Conventional electrocardiography or vectorcardiography was evaluated on Correlation between left ventricle and septum dipole activity and left ventricular muscle weight (r2 86%). The multiple dipole electrical source method diagnosed increased left ventricular muscle weight with 98% sensitivity and 84% specificity, correlating strongly with angiographic measurements (r2=86%).