Applicability of the Electro-Vectorcardiogram in Current Clinical Practice

Abstract

The electrocardiogram (ECG) has been reinvigorated by the identification of electrical alterations that were not definitely clarified before. In this context, and mainly regarding the definition of arrhythmogenic substrates, the association of the ECG with the vectorcardiogram (VCG) has gathered much more information about the cardiac electrical phenomena, thus allowing us to differentiate potentially fatal cases from benign ones. Obtaining a VCG concomitantly with the performance of an ECG has led to a significant gain in the definition of extremely sophisticated pathologies, which function suffer some type of structural or dynamic alterations, involving either the reduction or enhancement of ionic channels and currents. The classic aspects of the ECG/VCG association in the differential diagnosis of myocardial infarctions, conduction disorders, atrial and ventricular hypertrophies, and the correlations between these electrical disorders are still valid and assertive. The association of these pathologies is further clarified when they are seen through the ECG/VCG dyad. The three-dimensional spatial orientation of both the atrial and the ventricular activity provides a far more complete observation tool than the ECG linear form. The modern analysis of the ECG and its respective VCG, simultaneously obtained by the recent technique called electro-vectorcardiogram (ECG/VCG), brought a significant gain for the differential diagnosis of some pathologies. Therefore, we illustrate how this type of analysis can elucidate some of the most important diagnoses found in our daily clinical practice as cardiologists.

Impact of Prone Position on 12-Lead Electrocardiogram in Healthy Adults: A Comparison Study with Standard Electrocardiogram

“…When ECGs were recorded for patients in prone posture, precordial leads were always shown to have comparatively smaller P waves and notable Q waves in leads V1 through V3, which contributed to the misinterpretation as an anteroseptal myocardial infarction. These variations can be clarified through the vectorcardiograms [ 23 , 24 ]. The vector loop tracks the course of the action potential during the cardiac cycle.…”

A computational investigation into rate-dependant vectorcardiogram changes due to specific fibrosis patterns in non-ischæmic dilated cardiomyopathy

“…The VCG is regaining popularity as a means of comprehensively evaluating the electrical activation and repolarisation sequences during a cardiac cycle through visualising, and quantifying, the movement of the net electrical cardiac dipole [45] , [46] . VCG analysis has recently been used to facilitate patient-specific personalisation of electrophysiological computational models [47] , and VCG-QRS analysis used to assess differences in activation sequences in responders of cardiac resynchronisation therapy [34] .…”

Contribuição do vetorcardiograma no diagnóstico diferencial do padrão eletrocardiográfico de Brugada

“…Chevalier et al 35 [25][26][27] , a vetorcardiografia voltou a se destacar a partir da década de 90 38 .…”

“…A centralização cardíaca, possibilitada pela disposição dos eletrodos, resulta em alças vetorcardiográficas que facilitam o diagnóstico eletrocardiográfico em casos de dúvidas decorrentes de sobreposição dos fenômenos elétricos ou apresentações elétricas pouco usuais. Como exemplos, áreas inativas associadas a bloqueio de ramo e/ou bloqueio fascicular, préexcitação ventricular com sobrecarga de câmaras (ou áreas inativas), deslocamentos do ponto J na região ânterosseptal (padrão Brugada tipo 2, repolarização precoce mais anteriorizada, atraso final do ramo direito, padrão de atleta, variante do normal) 38 .…”

“…Assim, atualmente o vetorcardiograma continua sendo utilizado, pois revela anormalidades elétricas, pouco ou não detectáveis na análise eletrocardiográfica 23,[31][32][33]40 , além de ser um auxílio didático no ensino da eletrocardiografia 41 .…”