T Vector and Loop Characteristics Improve Detection of Myocardial Injury After Infarction

Abstract

Electrocardiography (ECG) is widely used to detect myocardial injury. ECG recordings after subendocardial, non-ST-elevation myocardial infarction (MI) may lack striking infarct patterns. A vectorcardiogram (VCG) of the T wave is a three-dimensional characterization of the ventricular repolarization and identifies abnormalities at an advanced level of analysis, which would normally be done manually from conventional ECG. Several parameters describing T vector loop morphology and T vector spatial orientation are examined with regard to their suitability for late MI detection. The discriminatory performance of VCG analysis is compared to that of conventional ECG analysis in identifying post-MI patients. T vector and T loop parameters as well as infarct indicators of the ECG recordings were calculated for 114 subjects: 59 patients (42 males; mean age: 54 years) 15 days after MI (11.9 ± 6.9 d) and 55 healthy controls (27 males; mean age: 49 years). ECG infarct indicators correctly identified 75.2 % of patients, while T vector and loop parameters correctly identified 83.2 % of patients. Discrimination analysis revealed a sensitivity of 66.7 % and a specificity of 77.4 % for conventional ECG, and a sensitivity of 71.7 % and a specificity of 88.7 % for the VCG parameters. T vector and loop characteristics were superior to conventional ECG in separating patients from controls. T vector ECG can improve the detection of myocardial injury and is applicable to the analysis of cardiac repolarization.

Modifications in Electrocardiographic and Vectordardiographic Morphological Parameters in Elderly Males as Result of Cardiovascular Diseases and Diabetes Mellitus

“…A significant decrease of the magnitude of T-loop maximal vector was observed for all cardiovascular diseases and for DM. The importance of this parameter in detection of myocardial injury after infarction was pointed out in [ 36 ];…”

Review of Processing Pathological Vectorcardiographic Records for the Detection of Heart Disease

“…From their results, they found that VCG features are able to diagnose AMI slightly better than ST elevation and T-wave maximum features together. Goernig et al (2015) dealt with T vector and T-loop parameters compared to a conventional 12-lead ECG. They used 114 patient records and analyzed T vector elevation, T vector azimuth, QRS-T angle, T area , T eigenv (expresses the form and the symmetry of the T loop) and T avplan (expresses the bulginess of the loop).…”

Alternative to Q Wave Diagnosis Using Cardiac Action Potential Propagation Time Measurement

“…It is stated [8] that patients with Q wave MI had worse prognosis compared to those without Q wave MI and hence warrant a closer follow up. The presently observed Q wave diagnosis relies on the small segment within 1 to 2 squares in the ECG record ( Figure 1).…”