Objective: The aim of this study was to analyze the relationship between QRS amplitude and left ventricular mass (LVM) in hypertensive patients identified by screening, with the focus on those without left ventricular hypertrophy (LVH).
Methods: The entire study group consisted of 189 healthy subjects (average 39.6 years) and 54 subjects with hypertension (average 52.4 years). The LVH-free subgroup consisted of 159 normal subjects and 30 hypertensive patients. Electrocardiograms were recorded and the magnitude of the maximum QRS spatial vector magnitude (QRSmax) was calculated from the RaVF, RV5 and SV2 amplitudes. The LVM was estimated echocardiographically. The specific potential of myocardium (SP) was calculated as a ratio of QRSmax to LVM.
Results: Contrary to higher LVM values in hypertensive subjects (240.2+/-58.7 g and 191.5+/-48.3 g, respectively), the QRSmax values (1.9+/-0.5 mV and 2.0+/-0.6 mV, respectively) and SP values (8.3+/-2.5*10(-3) mV/g and 11.3+/-4.4*10(-3) mV/g, respectively) were significantly lower as compared to healthy subjects in the entire study group. Also in the LVH-free subgroup the SP values were significantly lower in hypertensive patients (8.70+/-2.83*10(-3) mV/g and 10.98+/-4.79*10(-3) mV/g, respectively). The lower values of QRSmax and SP could not be explained by the differences in age and body mass index between the hypertensive patients and normal subjects.
Conclusion: We showed that the SP provides a more sensitive parameter for the evaluation of early hypertrophic remodeling as compared to separated evaluation of LVM and QRS voltage already in subjects with no signs of cardiac target organ involvement according to current clinical classification.