Relationship between parameters of myocardial electrical remodeling and parameters of contractile function, deformation and myocardium work in patients with chronic heart failure with low left ventricular ejection fraction and atrial fibrillation.

Aim    To compare electrocardiographic parameters and characteristics of myocardial contractility by echocardiography data in patients with chronic heart failure (CHF) with low left ventricular ejection fraction (LV EF) and atrial fibrillation (AF).Material and methods    The study included 66 patients with CHF and LV EF ≤40%. Electrocardiography was used to assess the QRS complex duration, QRS fragmentation, frontal QRS-T angle (fQRS-Ta), and 3D vectorcardiographic parameters, including the planarity of QRS loop, and the spatial QRS-T angle (sQRS-Ta). Echocardiography assessed LV EF, global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE).Results    Statistically significant correlations between electrocardiographic parameters and LV EF were not found. The presence of QRS fragmentation was associated with impaired GLS, higher GWW values, and lower GWE. A number of weak but significant correlations was observed: GLS worsened with increasing QRS duration, fQRS-Ta, and sQRS-Ta and decreasing QRS planarity index; GWW increased with increasing QRS duration; GWI, GCW, and GWE decreased as the QRS planarity index decreased. GWI decreased with increasing sQRS-Ta; GCW decreased with increasing fQRS-Ta and sQRS-Ta; GWE decreased with increasing QRS duration, fQRS-Ta and sQRS-Ta.Conclusion    Correlations were found between indicators of myocardial electrical remodeling and parameters of myocardial contractility, strain, and performance in CHF patients with low LV EF and AF. Further study of these parameters may be promising for assessing the severity of changes in myocardial structure and function in patients with various cardiovascular pathologies.

[Features of vectorcardiograms in patients with hypertension complicated by chronic heart failure with reduced left ventricle ejection fraction].

AIM: To explore the features of vectorcardiograms (VCG) of patients with essential hypertension complicated by chronic heart failure with reduced left ventricular ejection fraction (CHFrLVEF). MATERIALS AND METHODS: We analyzed VCGs of 70 hypertensive patients with CHFrLVEF and 275 hypertensive patients without clinical signs of CHF and with LVEF50%. We assessed the presence of rhythm and conduction disturbances, and the parameters of the synthesized VCG, i.e., module of the maximum QRS vector, planarity index of the spatial QRS loop (P/S), and spatial angle between the integral QRS and T vectors (sQRS-Ta). RESULTS: In hypertensive patients with CHF, certain conditions were detected more often as compared with hypertensive patients without CHF, i.e., atrial fibrillation (AF) in 52.9% vs 5.1%; p0.0001, and left bundle branch block (LBBB) in 38.6% vs 0.4%; p0.0001. The module of the maximum QRS vector and sQRS-Ta were significantly greater and P/S was significantly less in VCGs of patients with CHF. ROC-analysis showed that the presence of AF and LBBB just as VCG parameters assessed in this study provide clear discrimination between hypertensive patients with or without CHF both in the group as a whole and in the subgroups (1) without LBBB, (2) with sinus rhythm, and (3) with AF. sQRS-Ta was the most informative parameter (threshold 137, sensitivity 91%, specificity 92%). The P/S indicator at the optimal threshold value 0.92 was characterized by lower specificity (68%) with rather high sensitivity (79%). CONCLUSION: AF, LBBB, increased module of the maximum QRS vector and sQRS-Ta, and decreased P/S index are present in hypertensive patients with CHFrLVEF as compared with patients without CHF.

[On the history of vectorcardiography: past, present, future].

The vector concept in the analysis of the electrical signals of the heart began to be used at the dawn of the development of electrocardiology. For several decades, vectorcardiography has developed in parallel with electrocardiography; reached its peak in the 60s, and after a period of cooling experienced a resurgence since the early 90s, when it became possible to mathematically synthesize vectorcardiograms (VCG) from digital electrocardiograms in 12 leads. VCG reflects the same phenomena as electrocardiography, but allows you to calculate and visualize a number of three-dimensional characteristics of the electrical signals of the heart. The article describes the main milestones in the development of the VCG, the history of international cooperation in this area, the contribution of domestic scientists to this field of science. Modern promising areas of research related to the vector concept of the analysis of the electrical signals of the heart are briefly reflected.

The value of the spatial QRS-T angle for assessing the severity of heart damage in patients with arterial hypertension.

Aim      To study the relationship between clinical, echocardiographic, and laboratory indexes with increased QRS-T spatial angle (sQRS-T) in patients with arterial hypertension (AH).Material and methods  The study included 160 patients with AH, 61 (38 %) men and 99 (62 %) women aged 58 [49; 67] years. Patients with ischemic heart disease or His bundle blocks were not included. Echocardiography was used to determine the left ventricular end-diastolic dimension (LV EDD), left ventricular posterior wall thickness (LVPWT), interventricular septal thickness (IVST), relative wall thickness (RWT), left ventricular myocardial mass (LVMM), and LVMM index (LVMMI). Also, the following indexes were analyzed: office systolic and diastolic blood pressure (SBP, DBP), disease duration, body mass index, plasma levels of glucose, cholesterol, and creatinine, and glomerular filtration rate. The QRS-T spatial angle was calculated as an angle between the integral vectors QRS and T using a vectorcardiogram derived from a 12-lead digital electrocardiogram. Data are presented as median (25th percentile; 75th percentile].Results The QRS-T spatial angle for the group was 65 [43; 90]°. The QRS-T spatial angle increased with increases in the AH grade (grade 1 AH, 55 [37; 74]°; grade 2 AH, 60 [41; 82]°; grade 3 AH, 88 [62; 107]°; р<0.0001); the AH stage (stage 1, 50 [41; 77]°; stage 2, 68 [44; 93]°; stage 3, 78 [59; 110]°; р=0.0002), and the cardiovascular risk degree (low and moderate risk, 49 [37; 70]°, high risk, 62 [43; 88]° (р=0.005); very high risk, 88 [61; 117]° vs. high risk, 62 [43; 88]° (р=0.0002). The QRS-T spatial angle was greater with diabetes mellitus (78 [60; 117]°) than without it (63 [43; 89]°) (р=0.03). Weak but significant correlations were found between sQRS-T and body mass index (r=0.2; p<0.01), SBP (r=0.4; p<0.0001), DBP (r=0.2; p<0.01), LV EDD (r=0.2; p<0.01), LV PWT (r=0.3; p<0.001), IVST (r=0.3; p<0.001), LVMM (r=0.3; p<0.001), LVMMI (r=0.3; p<0.001), and blood glucose (r=0.2; p<0.01).Conclusion      In patients with AH, a large QRS-T spatial angle is related with significantly higher values of SBP and DBP, LV dimension, blood glucose, and body mass index.

[Factors associated with an increase in spatial and frontal QRS-T angles in patients with anterior myocardial infarction].

Aim    To determine existence of a relationship between any clinical, echocardiographic and coronarographic factors and increased spatial QRS-T (sQRS-T) angle and frontal QRS-T (fQRS-T) angle in patients with anterior myocardial infarction.Material and methods    This study included 137 patients aged 62 [53; 72] years with anterior acute myocardial infarction managed at the A.L. Myasnikov Institute of Clinical Cardiology. fQRS-T was calculated as the module of difference between the frontal plane QRS complex axis and the T wave axis. sQRS-T was calculated as a spatial angle between QRS and T integral vectors from a synthesized vectorcardiogram.Results    fQRS-T values for a group (median [25th; 75th percentile]) were 81 [37; 120]°; sQRS-T values were 114 [80; 141]°. The correlation coefficient between fQRS-T and sQRS-T values was 0.41 (p<0.001). fQRS-T weakly but statistically significantly correlated with patients' age (r=0.28; p=0.001), left ventricular ejection fraction (LV EF, r= -0.22; p=0.01), and glomerular filtration rate (r=-0.32; p=0.0002). sQRS-T weakly but statistically significantly correlated with left ventricular end-diastolic dimension (r=0.24; p=0.0048), LV EF (r=-0.28; p=0.0009), and the number of affected segments according to echocardiography data (r=0.27; p=0.002). fQRS-T values were significantly higher in the presence of concurrent arterial hypertension. sQRS-T values were significantly higher in the presence of a history of chronic heart failure. Both fQRS-T and sQRS-T values increased with increasing number of affected blood vessels and Killip class of acute heart failure.Conclusion    In patients after anterior acute myocardial infarction, increases in fQRS-T and sQRS-T are associated with more severe damage of the vasculature, decreased LV EF, and, thus, more severe clinical course of disease.

[Diagnostic and prognostic significance of QRS-T angle].

The angle between theQRSandTvectors reflects the consistency or inconsistency of the processes of de- and repolarization of the ventricles of the heart and is considered one of the indicators of global electrical heterogeneity of myocardium. In recent years, the prognostic value of theQRS-Tangle has been demonstrated in relation to total and cardiovascular mortality, both in the population and in various groups of patients. The mechanisms of this phenomenon are not completely clear. The review analyses studies published over the past five years on the relationship between theQRS-Tangle and mortality, as well as coronary heart disease and heart failure. Possible mechanisms for increasing theQRS-Tangle are discussed. Data are given on the use of theQRS-Tangle in diagnostic and prognostic scales, including in combination with other indicators of global electrical heterogeneity of myocardium.

[Factors Associated with the Increase in Spatial and Frontal QRS-T Angles in Patients with Inferior Myocardial Infarction].

Aim      To identify clinical, echocardiographic, and angiographic factors related with an increase in the frontal QRS-T angle (fQRS-T) and the spatial QRS-T angle (sQRS-T) in patients with inferior myocardial infarction.Material and methods  The study included 128 patients aged (median [25th percentile; 75th percentile]) 59.5 [51.5; 67.0] years diagnosed with inferior wall acute myocardial infarction. fQRS-T was calculated as a module of difference between the QRS axis and the Т axis in the frontal plane. sQRS-T was calculated by a synthesized vectorcardiogram as a spatial angle between the QRS and Т integral vectors.Results The fQRS-T for the group was 54.0 [18; 80] and sQRS-T was 80.1 [53; 110]. The correlation coefficient for fQRS-T and sQRS-T values was 0.42 (p<0.001). Both fQRS-T >80° and sQRS-T >110° compared to their lower values were associated with a higher frequency of history of postinfarction cardiosclerosis (44% and 12 %, respectively; p<0.05), a lower left ventricular ejection fraction (51 [47; 60]% at fQRS-T >80° and 55 [50; 60]% at fQRS-T <80° (p<0,05); 49 [44; 57]% at sQRS-T >110° and 57 [51; 60] % at sQRS-T <110° (p<0.01); more frequent development of acute heart failure (16 and 2 %, respectively; p<0.05); and early postinfarction angina (13 and 2 %, respectively; p<0.05). The increased fQRS-T was associated with a higher incidence of damage to the circumflex artery (45 and 20 %, respectively; p<0.05). The increased sQRS-T was associated with a history of arterial hypertension (97 and 76 %, respectively; p<0.05), chronic heart failure (22 and 3 %, respectively; p<0.05), chronic kidney disease (19 and 4 %, respectively; p<0.05), and a larger myocardial lesion (mean number of damaged segments by echocardiography was 3.8 [2; 6] at sQRS-T >110° and 2.6 [1; 4] at sQRS-T <110°; p<0.01). sQRS-T was significantly greater in multivascular damage (87 [68; 121]° than in one- or two-vascular damage (72 [51; 100]°; p<0.05). sQRS-T values were significantly lower with spontaneous reperfusion (66 [29; 79] than without spontaneous reperfusion (77 [55; 115]°; p<0.05).Conclusion      In patients after inferior wall acute myocardial infarction, increases in fQRS-T and sQRS-T were associated with more severe damage of coronary vasculature, decreased left ventricular ejection fraction, and more severe course of disease.

Comparison of the integral indices of the vectorcardiogram with the data of echocardiography in patients with idiopathic and chronic thromboembolic pulmonary hypertension.

AIM: The aim of the work is to compare vectorcardiographic (VCG) variables - spatial QRS-T angle and electrocardiographic ventricular gradient (VG) with echocardiography (EchoCG) data in patients with idiopathic pulmonary hypertension (IPH) and chronic thromboembolic pulmonary hypertension (CTEPH). MATERIALS AND METHODS: In 40 patients with IPH and 40 patients with CTEPH at the age of 45±12 years, systolic pulmonary artery pressure (SPAP); the sizes of heart chambers, parameters of RV systolic and diastolic function were evaluated with EchoCG. The QRS-T and VG angles were calculated on the VCG, derived from 12-lead digital ECG. RESULTS: In all patients SPAP was greater than 40 mm Hg (mean 83±18 mm Hg), EchoCG data indicated hypertrophy and dilatation of RV, its systolic and diastolic function; dilatation of the right atrium (RA). Prognostically unfavorable changes in EchoCG were observed: the presence of pericardial effusion in 35 (44%) patients, RA area greater than 26 cm2 in 18 (23%) patients; TAPSE less than 1.5 cm in 37 (46%) patients. EchoCG and VCG variables had statistically significant differences in patients with III-IV functional class in comparison with I-II functional class. Statistically significant moderate correlations between VCG and EchoCG variables were revealed. VCG variables allowed to separate patient groups with the presence and absence of prognostically unfavorable changes in EchoCG with sensitivity from 54 to 78% and specificity from 66 to 87%. CONCLUSION: In patients with IPH and CTEPH, changes of QRS-T angle and VG correlate with SPAP, the size of RV and RA, parameters of RV systolic and diastolic function. The possibility of the use of QRS-T angle and VG for the detection of patients with prognostically unfavorable echocardiographic changes in the general group of patients with IPH and CTEPH has been shown.

[A case of primary diagnosis of patent ductus arteriosus at the age of 75 years]. / Sluchai pervichnoi diagnostiki otkrytogo arterial'nogo protoka u patsientov v vozraste 75 let.

The paper describes a case of primary diagnosis of functioning patent ductus arteriosus in a 75-year-old female patient.

[Changes in orthogonal ECG in hypertensive patients taking different antihypertensive therapy].

AIM: To ascertain changes in orthogonal ECG in hypertensive patients taking different antihypertensive treatment. MATERIAL AND METHODS: Orthogonal ECG parameters and those of 24-h blood pressure monitoring (BPM) were examined before and after antihypertensive treatment with different drugs in 95 hypertensive patients aged 47 +/- 1 years. Of them, 14 patients received trandolapril+verapamil SR for 2 months, 13 patients--candesartan for 3 months, 25 patients--ramipril for 5 months, 26 patients--carvedilol for 4 months, 10 patients--atenolol for 8 months, 7 patients--doxasozine for 5 months. RESULTS: 24-h BPM parameters improved in all the groups. Initially, conventional ECG evidence on left ventricular hypertrophy was not seen in 86% patients. Dynamics of orthogonal ECG showed that parameters which increase in left ventricular hypertrophy decrease in response to treatment in patients with baseline values above the median. Parameters G and Gx, which in left ventricular hypertrophy diminish, rise significantly in patients with baseline values under median due to therapy. Treatment with impact on renin-angiotensin system reduced voltage parameters of orthogonal ECG, improved G characterizing repolarisation. Treatment with adrenoreceptors blockers reduced IADI. CONCLUSION: The analysis of parameters of orthogonal ECG reveals positive dynamics in response to treatment in patients with insignificant changes on ECG in short follow-up. Drugs of different groups change different parameters of orthogonal ECG.

[Secondary repolarization changes in patients with left ventricular hypertrophy].

AIM: To estimate the detection rate of tension syndrome and nonspecific repolarization changes in patients with arterial hypertension (AH). SUBJECTS AND METHODS: The electrocardiograms of 234 patients with AH (104 males and 130 females) were analyzed, by taking into account the magnitude of blood pressure (BP) elevation, the degree of an overall cardiovascular risk, the grade of hypertensive disease (HD), the presence of coronary heart disease (CHD), as well as echocardiographic and electrocardiographic voltage criteria for left ventricular hypertrophy (LVH). RESULTS: The classical tension syndrome and nonspecific repolarization changes were observed in 7 and 26% of cases, respectively; no significant differences were found in their detection rates between the males and females. The frequency of repolarization changes were associated with the presence of CHD in the women and with the magnitude of BP elevation, the degree of a cardiovascular risk, the grade of HD, and the presence of both echocardiographic and electrocardiographic signs of LVH. CONCLUSION: Ventricular repolarization changes in patients with AH are a sign of severe cardiac lesion and determine the need for meticulous attention.

[Quantitative repolarization indices in diagnosis of left ventricular hypertrophy in hypertensive patients].

AIM: To determine informative value of quantitative parameters of orthogonal ECG repolarization phase in diagnosis of left ventricular hypertrophy (LVH) in hypertensive patients. MATERIAL AND METHODS: A total of 210 healthy subjects and 241 hypertensive patients with LVH (LV myocardium mass index > 125 g/m2 in males and > 110 g/m2 in women) comprised two groups--control and test. The study was made of quantitative parameters (components X, Y, Z, modules and angles of azimuth and elevation) of wave T integral vector, wave T maximal vector, ST vector, ventricular gradient; spatial and projection areas of wave T, the angle between integral vectors of spatial waves QRS and T (phi angle). RESULTS: The test group had reduced X, Y components and elevated vectors, their azimuth and phi angle. Most informative for repolarization were components X of T maximal and integral vectors being as informative as Rx+Sz and Cornel product. The method of multiple regression analysis was used to plot discriminant function taking account of most informative indices of depolarization and repolarization--Rx+Sz and X component of T maximal vector. The area under ROC curve for this function was greater than for the variables alone and Cornel product in both groups (0.90 +/- 0.02 and 0.86 +/- 0.02, p < 0.05 for the control and test group, respectively). CONCLUSION: Quantitative parameters of repolarization phase can improve LVG diagnosis in hypertensive patients.

[Changes in parameters of orthogonal ECG in hypertensive patients given combined antihypertensive treatment].

AIM: To evaluate changes in parameters of orthogonal ECG in hypertensive patients on trandolapril+verapamil combination. MATERIAL AND METHODS: Eighteen patients before and after 8-week therapy were examined using orthogonal ECG and 24-h monitoring of blood pressure. Computer processing of orthogonal ECG was made with calculation of some vectorcardiography (VCG) and d mapping parameters. Also, 24-h blood pressure monitoring was made. RESULTS: 8-week therapy significantly reduced mean diurnal and nocturnal systolic and diastolic blood pressure (SBP, DBP), improved their variability. In patients with VCG signs of left ventricular hypertrophy the treatment significantly diminished some VCG parameters. A direct correlation was found between initial diurnal SBP variability and SQRSxyz, SQRSxz; dynamics of nocturnal SBP variability and dynamics of SQRSxyz, SQRSxz and Rx+Sz (r = 0.7; p < 0.05). A direct correlation was between dynamics of SBP and IADI (r = 0.7; p < 0.05). CONCLUSION: Hypertensive patients treated with a fixed combination trandolapril/verapamil exhibit a positive trend not only in parameters of 24-h monitoring of blood pressure but also in parameters of orthogonal ECG.

New approaches to the diagnosis of left and right ventricular hypertrophy by means of dipolar electrocardiotopography.

OBJECTIVE: The aim of this work was to describe a new approach to noninvasive differential diagnosis of left and right ventricular hypertrophies (LVH and RVH) caused by the arterial or lung hypertensions. METHODS: The vectorcardiographic measurements were analyzed by means of dipolar electrocardiotopography (DECARTO) technique based upon a simplified spherical model of the heart. The characteristics of LVH and RVH are obtained from the decartograms of activation duration. The integral indices of hypertrophy for the left ventricle and right ventricle (ILVH and IRVH) are formulated on the basis of the surface integrals of activation duration calculated over the regions where left and right ventricles are projected. The diagnostic decision is made through the comparison of ILVH and IRVH with specified threshold values. For comparison, the sums of wave amplitudes used in the orthogonal vectorcardiography, Rx+Sz for LVH and Rz+Sx for RVH, were also considered. RESULTS: The study included 141 males and 191 females aged 45+/-15 years, with reliably verified state of the heart, in particular, 143 persons without hypertrophy, 129 persons with LVH, and 60 persons with RVH. The ROC curves for criteria under study were statistically analysed. As a result, the ILVH criterion is preferable to Rx+Sz with confidence level greater than 95%, and the IRVH criterion is preferable to Rz+Sx with confidence level close to 99%. CONCLUSION: The proposed DECARTO method, initially intended mainly for intelligible-pictorial visualization of vectorcardiographic data, provides also some increase of diagnostic accuracy in recognition of the left and right ventricular hypertrophies as compared to the standard electrocardiography and orthogonal vectorcardiography.

[Informative value of orthogonal electrocardiogram in the diagnosis of the left ventricular hypertrophy].

AIM: To estimate the informative value of orthogonal ECG parameters for the diagnosis of left ventricular hypertrophy (LVH). MATERIALS AND METHODS: The study comprised 142 apparently healthy individuals and 125 patients with arterial hypertension (AH) and LVH (left ventricular mass index more than 125 g/m2 for males and more than 110 g/m2 for females). Characteristic curves (ROC curves) were used to describe and compare the informative value of vectorcardiographic, demapping criteria for L VH with the informavalue of the Sokolov-Lyons criterion, the Cornelian index, and the Cornelian product. RESULTS: The informative indices of orthogonal ECG were Rx + Sz and IADIM: the area under the ROC curve was 0.89 +/- 0.02 and 0.88 +/- 0.02, respectively, which was significantly higher than with the Sokolov-Lyons criterion (0.64 +/- 0.04; p < 0.05) and similar to the Cornelian product (0.84 +/- 0.03). Of great informative value is the angle phi (area under the ROC curve was 0.88 +/- 0.04) in males and the area of QRS loop in the horizontal plane (area under the ROC curve was 0.89 +/- 0.03) in females. With 96% specificity, the male sensitivity of IADIM was 80%, Rx + Sz--73%, which was significantly higher than that of the Cornelian index (56%; p < 0.05) and the Sokolov-Lyons criterion (27%; p < 0.05). With 96% specificity, the female sensitivity of IADIM was 73%, Rx + Sz--84%, SQRSxz--70%, which was significantly higher than that of the Cornelian index (49%; p < 0.05), the Cornelian product (55%; p < 0.05), and the Sokolov-Lyons criterion (30%; p < 0.05). CONCLUSION: The threshold values of the most informative indices of orthogonal ECG are presented, which could provide the optimum sensitivity-specificity ratios. These values allow cardiac lesions to be detected in hypertensive patients with normal 12-lead ECG.

[New approaches to diagnosis of left ventricular hypertrophy by dipolar electrocardiography].

AIM: To show possibilities of dipolar electrocardiography (DECG) in diagnosis of left ventricular hypertrophy (LVH). MATERIAL AND METHODS: We made DECG in 151 healthy subjects and 158 hypertensive patients. To characterize DECG quantitatively, we used the integral activation duration index (IADI) calculated as a weighted sum of the areas with different duration of activation, module of the maximal vector QRS, QRSxIADI (IADIM). RESULTS: In patients with left ventricular myocardial mass index (LVMMI) under 150 g/m2, sensitivity of DECG was 38-49%, in the index over 150 g/m2 sensitivity reached 38-75%, specificity 89-98% compared to healthy examinees and 72-82% compared to hypertensive patients without LVH. The IADIM parameter correlates directly (moderate correlation) with duration of QRS complex and LVMMI. CONCLUSION: Possibilities of using parameters IADI and IADIM for assessment of electrophysiological myocardial remodeling and their correlation with other methods need further investigations.

[Electrocardiographic picture in patients with congenital defect of atrial septum operated upon in adult age]. / Elektrokardiograficheskaia kartina u bol'nykh s vrozhdennym defektom mezhpredserdnoi peregorodki, operirovannykh vo vzroslom vozraste.

Electrocardiograms from 30 patients with congenital atrial septal defect operated upon in adult age were analyzed. One of frequent variants of QRS configuration in standard leads was SIqIII type. It was observed in 50% of patients. Most frequent (in 67% of patients) variants of QRS configuration in lead V1 were rSr' and rSR'. Signs of right ventricular hypertrophy were most often found in a group of patients with high pulmonary hypertension. Changes of terminal portion of ventricular complex such as negative or biphasic T waves were found in 29 of 30 patients (in 63% of cases these changes were localized in leads V1-V3).

Changes of decartograms under gravitational acceleration and microgravity.

The Decarto technique was used to study the orthogonal ECGs recorded in 23 subjects during parabolic flights (44 records). A parameter of the instantaneous decartograms, namely the activation area (AA), which is the total area of the depolarization front projection on the image sphere, was analyzed. We compared the values of AA during the periods of horizontal flight, upward parts of all parabolas, and the initial 10 s of microgravity of all parabolas. According to the characteristics of the vectorcardiograms and AA, all subjects were subdivided into 3 groups: with increased electric activity of the right ventricle (I), the left ventricle (II) and both ventricles (III). Changes of AA with change of gravitational levels in these groups showed some differences. In groups I and II, the AA of the initial part of the QRS complex increased during microgravity and decreased during hypergravity. In group III it decreased during microgravity and changed variously during hypergravity. The AA of the middle part of the QRS complex decreased during microgravity and increased during hypergravity, and these changes were more pronounced in group III. The changes of AA in groups I and II may be explained by the Brody effect. In group III, AA seems to be influenced by some additional factors, possibly by changes in the intramyocardial or intraventricular blood volume. The AA of the last part of the QRS complex increased during microgravity and decreased during hypergravity in all groups. This may be explained by an effect of mutual neutralization of depolarization fronts related to the changes of the QRS duration.(Fig. 3, Ref. 4)

Two-year dynamics of vectorcardiography parameters in patients with primary pulmonary hypertension.

VCG data (McFee--Parungao system) were obtained from 12 patients with primary pulmonary hypertension (PPH). During 2 years, VCG investigations were repeated from 2 to 5 times. Various VCG-parameters were analyzed. Space and horizontal QRS areas, projection of integra QRS vector to axis y and the sum of Rx and Sx were diagnostically most significant. Their values proved abnormal at the beginning of survey. In the course of observation, states of the right heart chambers together with VCG-parameter dynamics were investigated in every patient. States of the right cardiac chambers improved in 4 patients. In all of them the parameter turned to normal values. In two patients, during the monitoring time monotonous increase of parameters was observed, with the state of the right heart chambers declining. In 6 patients, state of right heart chambers appeared relatively stable. In these patients, values of all the parameters were either stable or insignificantly changeable around some mean values. Thus, the dynamics of VCG-parameters makes it possible to estimate adequately the states of the right cardiac chambers in PPH patients. (Tab. 1, Fig. 4, Ref. 4)

Decarto technique in long-term observation of patients treated for primary pulmonary hypertension.

Techniques for noninvasive observation of heart states play an important part in experimental and therapeutic cardiology. The objective of this work is to describe a new method for intelligible pictorial representation of data acquired by an orthogonal electrocardiographic lead system and demonstration of possibilities of this method in estimating the results of longterm treatment for a cardiac disease. The method used, dipole electrocardiotopography (DECARTO), provides a set of maps (decartograms) that depict in an explicit form the instantaneous, as well as integral electrophysiological properties of the heart during the excitation cycle. The observed group of patients contained 10 females and 2 males with primary pulmonary hypertension. It was found that in all but one cases tested, the features of the maps strongly correlated with the results of the other diagnostical methods and clinical findings. The trends to improvement (6 cases), stabilization (4 cases), or deterioration (1 case) of the heart state were clearly indicated. In one case, however, the interpretation of the decartograms was ambiguous. The advantage of the DECARTO technique lays in clearness of data representation for visual analysis and facilitation of electrophysiological and anatomical interpretation of the data. (Fig. 6, Ref. 2)