[The diagnostically significant indices of the corrected axial ECG system in the differentiation of ischemic heart disease and dilated cardiomyopathy].

The common uniformity of electrocardiographic changes in coronary heart disease (CHD) and dilated cardiomyopathy (DCMP) in the lead XII, namely low QRS complex voltage, T-wave inversion, cardiac arrhythmias, atrioventricular and intraventricular conduction disturbances, served as the basis for searching for individual or combined lesion signs quantitatively diagnostically significant for CHD and DCMP. For this purpose, 217 patients were examined. Out of them 83 were included into a group of healthy persons and 134 were patients who were divided into two groups: 60 with chronic CHD and 74 with DCMP.

[Computer visualization of three-dimensional vectorcardiographic loops in the diagnosis of the enlargement of cardiac segments].

A nontraditional method was proposed for computed visualization of three-dimensional vectorcardiographic loops in the projections on the two-dimensional planes the least departing from the appropriate loops in terms of root-mean-square deviation. The proposed visualization makes it possible to make a differential diagnosis of isolated forms of enlarged cardiac portions, including those of enlarged atria with high certainty.

[Vector electrocardiographic features in patients with hypertrophic cardiomyopathy].

The examination indicated that abnormal Q and QS waves recorded along the azes Z and Y in the adjusted lead system far clearly reflected a predominant site of suspected focal and scarring lestoh in hypertrophic cardiomyopathy (HCM) as in coronary heart disease (CHD) (the anterior site in the Z lead and inferior one, in the Y lead), however, the difference in their quantitative characteristics do not fulfil the goals of the electrocardiographic differentiation between HCM and CHD. To differentiate HCM and CHD in the presence of Q and QS waves, a characteristic complex of signs was identified: elevated waves Rx (greater than or equal to 17.5 mm), Sy (greater than or equal to 7.

[The ECG in dilated cardiomyopathy with different degrees of the manifestation of cardiosclerosis].

ECG of 46 patients who had died from dilated cardiomyopathy were retrospectively examined in order to evaluate characteristic ECG changes in relation to myocardial sclerotic severity according to autopsy findings. It was found that 1) one of ECG features in this disease is QRS complex morphology in left chest leads in the form of "rS", "RS" as being independent of cardiosclerotic severity. The deep wave S V5-V6 was due not only to rotation shifts during left ventricular hypertrophy (dilatation), which was typical of dilated cardiomyopathy right ventricle mass; 2) as cardiosclerosis progresses, the frequency and severity of intraventricular conduction disturbances progressively increase; 3) ectopic arrhythmias and atrioventricular block are not caused only by cardiosclerosis and likely to be induced by drug therapy (cardiac glycosides); 4) despite cardiosclerotic development in patients with dilated cardiomyopathy, ECG retains voltage criteria of enlarged cardiac cavities; 5) enlarged cardiac cavities can be determined by standard 12 ECG leads in 73.

[Electrovectorcardiographic characteristics of shifting repolarization phase curves in patients with hypertrophic cardiomyopathy and ischemic heart disease with arterial hypertension].

Possible electrovectorcardiographic approaches to the diagnosis of hypertrophic cardiomyopathy (HCMP) are considered on the basis of a study of 85 HCMP patients, 44 coronary patients with postinfarction cardiosclerosis and arterial hypertension (CD + AH), and 83 normal subjects. Particular attention was paid to cases where myocardial scary changes and left-ventricular hypertrophy were detected electrocardiographically as their interpretation was difficult because of similar changes in the QRS complex being typical for postinfarction cardiosclerosis. An analysis of quantitative and qualitative changes in the end segment of the QRS complex demonstrated a specific pattern of repolarization shift in patients with HCMP and CD + AH.

[Clinical aspects of differential-diagnostic ECG analysis in practical electrocardiography].

Individual assessment of ECG in any field of medicine requires, in the first place, analysis of clinical findings and, in the second place, the selection of a "specific" complex of symptoms from recorded ECG deviations reflecting cardiopathology proper (hypertrophy of different parts of the heart, a focal process of different layers, the extent and stages of disease development, SA, AV and intraventricular block, a certain type of disturbance of impulse formation, etc.). One should bear in mind the arbitrary concept of specificity of any ECG-syndrome and its components applied specially to differential ECG diagnosis between different processes.

[Diagnosis of combined myocardial ventricular hypertrophy using precordial mapping. II. Selection of the parameters of the cartogram of diagnostic significance for the differential diagnosis of combined myocardial hypertrophy and its isolated forms].

A new approach to the choice of diagnostic criteria of combined ventricular hypertrophy (CVN) is proposed: after determination of EKG parametres differing from the norm are separately compared to the EKG parametres in isolated left ventricular hypertrophy (LVH) and right ventricular hypertrophy (RVH). The diagnostic parametres were chosen on the basis of computer statistical analysis of EKG-35 data of 136 patients with CVH, 39 with LVH, 57 with RVH and 71 normal subjects. For differentiation from LVH the amplitude/area ratio (S10 + S17 + S24)/(S1 + S8 + S15) and R27/R17 was effectively used, for differentiation from RVH parametres R14/R1 or S25/S27 are recommended.

[Diagnosis of combined myocardial ventricular hypertrophy using precordial mapping. I. Selection of the most informative cartogram leads in the diagnosis of combined myocardial hypertrophy].

On the basis of verified material (136 patients with combined myocardial hypertrophy--CMH, 39 with left ventricular hyperthrophy, 57 with right ventricular hyperthrophy and 71 normal subjects) a principally new approach to computerized quantitative analysis of the EKG data has been worked out. Results of study of the informative value of 35 praecordial EKG in the diagnosis of CMH are presented. The authors propose to use the amplitude and area of S and R waves as well as their sum calculated with the use of non-traditional leads.

[Diagnostic significance of the vectorcardiogram spatial indices in combined atrial dilatation].

Eighty-two apparently normal subjects and 90 patients with combined atrial dilatation were investigated, using automated amplified-image atrial VCG reproduction with an output of spatial characteristics of the Macfee-Parungao P loop, a method developed at the All-Union Center for Cardiologic Research (USSR Academy of Medical Sciences). Area enclosed by spatial P loop (SPxyz greater than or equal to 0.017 mV2), mean vector size (MPxyz greater than or equal to 120.

[Integral indices of the automatically reproduced spatial QRS loop in the diagnosis of different forms of myocardial hypertrophy].

A total of 249 patients with arterial hypertension taking a variety of clinical forms, primary pulmonary hypertension, dilatation cardiomyopathy, congenital heart diseases with secondary pulmonary hypertension were examined and allocated to 3 groups: 125 patients with left-ventricular hypertrophy (LVH) (group 1); 44 patients with right-ventricular hypertrophy (RVH) (group 2), and 80 patients with combined hypertrophy of both ventricles (CH). Eighty-one normal subjects were taken as controls. New parameters of diagnostic significance were identified by automated reproduction of vectorcardiographic spatial QRSxyz loop (the Macfee-Parungao system) and computer analysis of vectorcardiographic parameters, that improve electrocardiographic diagnosis of cardiac hypertrophies, as compared to the conventional criteria, bringing its accuracy to 88.

[Results of a 5-year prospective observation of ischemic heart disease patients with stable stenocardia due to stenosing coronary arteriosclerosis].

A prospective five-year study and medicinal treatment were conducted in 317 coronary patients with stable angina in the absence of any signs of heart failure, and stenosing coronary arterial atherosclerosis as evidenced by selective coronary angiography. Total mortality was 2.8%, and the incidence of documented non-fatal myocardial infarction was 3.

[Cartogram of 35 ECG leads in hypertrophy of the right ventricle of the heart].

Automatedly-reproduced cartograms of 35 electrocardiographic leads in 27 cases of isolated right-ventricular hypertrophy (RVH) were analysed in relation to the latter's roentgenocardiometric markedness, and the obtained results were substantiated in terms of spacial vectorcardiography. A direct correlation was established between cartographic and roentgenocardiometric data in cases of moderate RVH that was absent in marked RVH. The correlation between cartographic and vectorcardiographic parameters was, on the contrary, only slightly expressed in moderate RVH and high in marked RVH cases.

[Approaches to electro- and vectorcardiographic differentiation of the signs of focal and cicatricial myocardial lesions in left-ventricular hypertrophy].

Electro- (12 and 35 ECG leads) and vectorcardiographic (3 orthogonal leads) examination of 75 patients with arterial hypertension and left-ventricular hypertrophy (LVH), 28 of which also had documented stenosis of one or more coronary arteries, was carried out using an automatic system of graphic registration and quantification of ECG-35 and VCG parameters. Electro- and vectorcardiographic signs of "pure" LVH and LVH accompanied by CHD relevant for their differential diagnosis were established. The principal singled out difference criteria include NQ (Q registration zone) and SQRSxyz (space QRS loop area), while Q (Q-wave sum), H0QRSxyz 0.

[Method of enhancing the diagnostic information value of the atrial vectorcardiogram].

An automated differentiation of the P loop from other VCG loops, its 20-fold magnification, visualization, and computation of its major spatial and projection parameters have been made possible, giving precise information on its configuration, duration, the direction of recording, as well as relative positions and directions of its instantaneous vectors. Digital computerization of the traces has produced different vector and scale characteristics of the spatial Pxyz loop.

[Spatial parameters of the automatically reproduced QRS loop of the VCG in healthy subjects].

The findings of the VCG automatic construction in 55 healthy subjects with different axial and positional variants of ECG were analyzed . The applied method of the automatic corrected VCG construction has shown that QRS loop morphology coincides with the classical forms of VCG described before in healthy persons. The data of the automatic calculations of spatial characteristics demonstrated the orientation stability according to the angle--azimuth, max QRSxyz , S/2 QRSxyz and the integral vector-- AQRSxyz , i.

[Method for the automated mapping of 35 ECG leads].

The method of recording the ECGs, inputting them into a computer and automatic analysis of 35 ECG leads is described. The proposed method largely diminishes the time expenditure and difficulties in obtaining and analysing 35 ECG lead mapping grams, as the computer makes all measurements and calculations and produces a final document.

[Spatial characteristics of the P loop in normal subjects and in patients with an enlarged right atrium].

The studies performed have shown that: 1) using automatic reproduction of 10-20-fold magnified images of P-loop it is possible to learn its configuration, duration, recording direction, position and orientation of its moment vectors; 2) using digital computer list output of curves it is possible to determine numerical values of PXYZ-loop parameters and its vector and scalar characteristics; 3) for the diagnosis of right atrial dilatation (RAD) the assessment of vector values is more important than their orientation by azimuth and elevation angles; 4) the increase beyond normal (M + 2 sigma) of space vector values of PXYZ-loop - P0.25 greater than 0.16 mV, -Pmax greater than 0.

[ECG in endocardiac electric heart stimulation].

An electrocardiographic study was conducted in 126 patients with endocardial electric stimulation from the right-ventricular apex. All electrocardiograms were divided in 6 groups on the basis of the vector direction of the artificial ventricular complex in the frontal aspect and the complex' morphology in right and left standard leads. The clinical value of the proposed classification of artificial ventricular complexes is discussed.