Frontal Plane Vectorcardiograms: Theory and Graphics Visualization of Cardiac Health Status

Abstract

The electrocardiogram (ECG) is a representative signal containing information about the condition of the heart. The shape and size of the P-QRS-T wave, the time intervals between its various peaks, may contain useful information about the nature of disease afflicting the heart. However, these subtle details cannot be directly monitored by the human observer. Besides, these signals are highly subjective, and the symptoms may appear at random in the time scale. It is very taxing and time-consuming to decipher cardiac abnormalities based on these ECG signals. The Vectorcardiogram (VCG) is the vector loop in the 2-D frontal plane, indicating the magnitude and direction of the instantaneous heart electrical activity vector (HAV), which represents the sum of the dipole vectors located along the instantaneous depolarization wavefront. The HAV is constructed from the monitored 3-lead ECG signals, placed at the three vertices of the modified Einthoven triangle formed by the 3-lead system in the frontal plane of the torso. The VCG examines the electrical activities within the heart, using the ECG signals along the three sides of the modified Einthoven triangle, and displays electrical events in the 2-dimensional frontal plane. This study demonstrates the development of the heart-depolarisation vector-locus cardiogram (using modified Einthoven's triangle), as a diagnostic measure of the left ventricular depolarisation strength. Our work involves the reconstruction of the "equivalent heart vector" for the QRS complex from limb lead voltages of a sample ECG, and plotting the progression of the cardiac vector during the QRS complex. We have demonstrated the construction of the frontal plane heart-depolarization vector cardiogram (HDVC), as the path of the locus of the tip of the heart electrical activity vector, with initial and terminal points at the origin. In this work, we have shown characteristic patterns of HDVC for cardiac states namely, normal, bundle branch block, ventricular hypertrophy and myocardial infarction. We have demonstrated how HDVC can be diagnostically employed to characterize cardiac disorders, such as ventricular hypertrophy bundle branch block and inferior myocardial infarction.

The electrical determinants of increased wall thickness and mass in left ventricular hypertrophy

“…The VCG is useful due to its visual representation of the electrical activity and its spatial variation during the cardiac cycle (53). Initially, the VCG was constructed from a 3-lead ECG with the electrodes placed in the frontal plane of the torso in a modified Einthoven triangle.…”

Using MQIS to Improve Medical Quality - In the Case of Local Hospital

“…Developed and developing countries may thus adopt very different indicators in measuring the performance of health systems and different indicators may be relevant depending on the unit of analysis (e.g., facility, district, and nation) [7] As shown in Table 1 Table 2) and Long-term Care Indicators (shown in Table 3). These indicators, shown in the Tables, are currently being executed in domestic medical centers, regional hospitals and district hospitals.…”

Modern Electrocardiographic Methods of Estimation of Coronary Reperfusion at Thrombolysis in Acute Period of Myocardial Infarction

“…Its vector analysis is a promising area in detecting myocardial electrical instability. In recent years, in case of acute coronary pathology researchers use adjusted orthogonal systems of leads, including those according to Frank and Mac FiParunhao, not only in Ukraine [11] and Russia [12], but also in many countries of European Union (Sweden [13], Bulgaria [14]), as well as in the United States [15] Canada [16] Singapore [17]. I. T. Akulinichev methodic does not have the faults of vector analysis of ECG due to the location of electrodes near the heart instead of geometric shapes building.…”