Concentric remodelling detection by magnetocardiography in patients with recent-onset arterial hypertension

The aim of this work was to evaluate a number of magnetocardiographic (MCG) indices in their predictive ability for left ventricular (LV) concentric remodeling. Twenty-five male patients affected by essential hypertension for no longer than 15 months and presenting signs of LV remodeling participated in the study; 25 normal male volunteers of comparable age were evaluated as controls. All participants underwent Echocardiography (ECHO), Electrocardiography (ECG) and Magnetocardiography (MCG). Several MCG based indices were evaluated, namely the QRS integral, T integral, QRS-T integral, T/QRS integral, RS index and the variations of the Electrical Cardiac Axis (ECA) orientation. MCG indices were compared with ECHO parameters, i.e. Left Ventricular Mass Index (LVMI) and Relative Wall Thickness (RWT), and with ECG parameters, i.e. 12-lead standard ECG LVH Sokolow-Lyon and Cornell voltages. QRS integral values for patients and controls were significantly different (P = 0.03), whereas T Integral values showed only a tendency to differentiate between patients and controls (P = 0.15). No significant correlation between MCG and echocardiographic indices in patients was found; RWT showed a tendency to correlate with QRS integral (r = 0.34, P = 0.17) and with RS index (r = 0.49, P = 0.15), and LVMI showed a tendency to correlate with the variations of the ECA orientation (r = 0.38, P = 0.10). Our findings, also supported by preliminary results on patients affected by hypertension-induced LV hypertrophy, suggest a potential role of MCG in the evaluation of early electrophysiological alterations due to LV concentric remodeling.