New possibilities of electrocardiography: evaluation of the vectorcardiographic QRS loop planarity in patients with myocardial infarction

The aim of the work is to evaluate the planarity of the QRS loop and its relationship with systolic dysfunction of the left ventricle in patients in the subacute period of myocardial infarction (MI).Materials and methods. The ECG of 265 patients with a diagnosis of acute myocardial infarction were analyzed. The control group consisted of 55 healthy individuals. The planarity index was calculated as the ratio of the area of the QRS loop projection onto the plane (the polar vector of the QRS loop) and the true area of the QRS loop in space using a synthesized vectorcardiogram.Results. In patients with MI, the planarity index was significantly lower than in healthy individuals: 0,87 [0,71; 0,94] and 0,96 [0,93; 0,97], respectively, p