New approaches to the diagnosis of left and right ventricular hypertrophy by means of dipolar electrocardiotopography

OBJECTIVE The aim of this work was to describe a new approach to noninvasive differential diagnosis of left and right ventricular hypertrophies (LVH and RVH) caused by the arterial or lung hypertensions. METHODS The vectorcardiographic measurements were analyzed by means of dipolar electrocardiotopography (DECARTO) technique based upon a simplified spherical model of the heart. The characteristics of LVH and RVH are obtained from the decartograms of activation duration. The integral indices of hypertrophy for the left ventricle and right ventricle (ILVH and IRVH) are formulated on the basis of the surface integrals of activation duration calculated over the regions where left and right ventricles are projected. The diagnostic decision is made through the comparison of ILVH and IRVH with specified threshold values. For comparison, the sums of wave amplitudes used in the orthogonal vectorcardiography, Rx+Sz for LVH and Rz+Sx for RVH, were also considered. RESULTS The study included 141 males and 191 females aged 45+/-15 years, with reliably verified state of the heart, in particular, 143 persons without hypertrophy, 129 persons with LVH, and 60 persons with RVH. The ROC curves for criteria under study were statistically analysed. As a result, the ILVH criterion is preferable to Rx+Sz with confidence level greater than 95%, and the IRVH criterion is preferable to Rz+Sx with confidence level close to 99%. CONCLUSION The proposed DECARTO method, initially intended mainly for intelligible-pictorial visualization of vectorcardiographic data, provides also some increase of diagnostic accuracy in recognition of the left and right ventricular hypertrophies as compared to the standard electrocardiography and orthogonal vectorcardiography.