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Published in Anton Sebastian, A Dictionary of the History of Medicine, 2018
Vectorcardiography [Latin: vehere, to carry; Greek: kardia, heart + graphein, to write] The concept of representing the electrical forces of the heart by recording the vector forces from the surface of the body was proposed by Willem Einthoven (1860–1927) and G. Fahr in 1913. The vector loop cardiogram was developed by Hubert Mann (1895–1975) while a medical student in 1920. The vectorcardiogram was introduced into clinical medicine by Fritz Schellong of Germany in 1939. The term vectorcardiogram was suggested by Frank Norman Wilson (1890–1952) and F. D. Johnston in 1938.
Treatment of cardiac resynchronization therapy non-responders: current approaches and new frontiers
Published in Expert Review of Medical Devices, 2022
H. Immo Lehmann, Lana Tsao, Jagmeet P. Singh
The difficulty in this process of patient selection is that it has become more and more apparent that the 12-lead surface ECG may be rather simplistic and not reveal electrical dyssynchrony at the different myocardial levels that could subsequently influence CRT response [18,19]. In addition, there is considerable observer variability and use of different clinical definitions leading even more uncertainty [20]. A new parameter that has been promising is the 3-dimensional QRS complex area using vectorcardiography, ‘QRS area’ which has been found to be strongly associated with the CRT response in patients with a class one indication for CRT [8,21–23]. Notably, mechanical dyssynchrony as an additional selection criterion, as evidenced by echocardiogram and in the absence of a left bundle branch block, does not predict a positive CRT response. This has been shown in multiple studies including the EchoCRT trial [24].
Fragmentation of the QRS complex: the latest electrocardiographic craze?
Published in Acta Cardiologica, 2019
Some have advocated the use of a more quantitative approach of fQRS, for instance the derivative of dV/dT [5]. One could also figure out to perform a high precision analysis, sort of signal-averaged processing as for the search of late potentials, but inside the whole QRS complex [17]. Magnetocardiography has also been suggested, but it is not in routine use to-day. However, vectorcardiography can be utilised: a study with the quantitative assessment of vector loop morphology (roundness, planarity, thickness, rotational, and dihedral angles) showed that fQRS detected from the 12-lead ECG had low sensitivity (31%) for detecting QRS loop folding on the VCG [18].