State Of Left Ventricular Myocardium Research Articles

INFLUENCE OF THE ORIGINAL STATE OF THE LEFT VENTRICLE AND TECHNICAL FEATURES OF CORONARY ARTERY BYPASS SURGERY ON THE FUNCTIONAL SAFETY OF GRAFTS

The goal of research is to study the influence of the initial state of left ventricular myocardium, as well as the technical features of the coronary artery bypass graft (CABG) on the prognosis of the functioning of coronary shunts.Materials and methods. 46 men, who had CABG for stable angina class III, were examined. 23 of them had 2 type diabetes mellitus (DM2), 23 of them did not have carbohydrate metabolism disorders. On the eve of the surgery, all patients underwent transthoracic echocardiography to determine the indicators of left ventricular function. Information about the technical features of the CABG were taken from the surgical reports. One year after the surgery, all patients underwent a coronary and bypass angiography.Results. Occlusion of coronary shunts was detected in 10 patients with DM2, and in 6 patients without DM2 (p value for Fisher’s exact test is 0.177). A larger left ventricle end-diastolic and end-systolic diameter (p value for the Mann-Whitney test is 0.004; 0.012), as well as a larger left ventricle end-diastolic and end-systolic volume (p value for the Mann-Whitney test is 0.012; 0.006) were associated with the presence of coronary shunt occlusions in patients with DM2. Also in the group of patients with DM2, sequential venous shunts were significantly more frequently occluded (p value for Fisher’s exact test is 0.004). Dysfunctioning shunts were associated with abovementioned figures among patients without carbohydrate metabolism disorders.Conclusion. The results of the research confirm the mutual confounding influence of risk factors on the prognosis after CABG

Structural and functional state of left ventricular myocardium in patients with stage II hypertension depending on galectin-3 and aldosterone levels

The analysis of structural and functional state of the left ventricular myocardium was conducted in the article, which concerned the determination of the general morphological and functional echocardiographic parameters of the heart according to the existing recommendations of the American Echocardiographic Society and the European Society of Cardiovascular Imaging; assessment of the relative dimensions/volumes of the LA (left atrium); determination of the structural-geometric remodeling variant of the left ventricular (LV) according to Ganau (1992) also determining the functions of the heart valves in patients with stage II 1-3 degrees hypertension, of different age and gender depending on plasma levels of galectin-3 and aldosterone. Determined the end-systolic (mm) and end-diastolic dimensions of the LV (mm), the thickness of the interventricular septum (mm) and the posterior wall of the LV (mm) in diastole, aortic diameter (AD, mm), size right atrium (RA, mm) and right ventricle (RV, mm), anterior-posterior size of the left atrium (LA, mm) and its index (ILA, mm/m2), LA volume (LPV, ml) and ejection fraction left ventricle (FV globe, %) by the modified Simpson method. LV mass (LVM, g) was estimated by the Penn Convention formula, and LVM index (LVM, g / m2) as the ratio of LVM to body surface area using the Du Bois nomogram (m2). The EchoCG in color Doppler mode measured the early (Ve) and late transmittal (Va) (m\s), their ratio (Ve\Va), the early LF filling time (DT), and the isovolumic LF relaxation time (IVRT) (ms). Statistical processing of the study results was performed using standard methods using the StatSoft Statistica v application package. 12.0 as recommended. In the case of quantitative values, the results were presented as medians and interquartile ranges (25 and 75 percentiles), in the case of relative values, as percentages (%). Comparison of the quantitative values in the groups was performed using the U-Mann-Whitney and Kruskal-Wallis ANOVA test, the relative values by the criterion χ2. A difference of p<0.05 was considered plausible. The obtained data demonstrate that relatively high levels (RH) of both galectin-3 (>2.4 pg/ml) and aldosterone (>325 pg/ml) are identified with significant morphological and functional changes in heart parameters, namely: worse structural-geometric remodeling of LV (increase in cases of concentric hypertrophy (CH) and decrease in cases with normal geometry (NG) of LV). In order to exclude the fact of cross-influence of neurohormones on echocardiographic parameters of the heart, the alignment of the groups in terms of aldosterone and galectin-3 levels was conducted. The analysis turned to be optimal in groups with galectin-3 level of ->2.0 and ≤2.0 pg/ml and aldosterone level of - >290 and ≤290 pg/ml. As a result, it was detected that galectin-3 has a greater pathophysiological effect than aldosterone on such indices as: an increase in aortic diameter; increase in right and left heart chambers dimensions; LVMMI (left ventricular myocardial mass index) value and increase in systolic, diastolic myocardial stress, increase in the number of cases with CH (concentric hypertrophy) and decrease in cases with normal geometry (NG) of LV. Aldosterone level is associated with an increase in dimension/volume indices of LA, calculated per patient’s body area.

Functional state of the myocardium and criteria for poor prognosis in mitral valve prolapse

Aim. Study of the fnctional state of left ventricular myocardium and determination of diagnostic criteria of poor prognosis of mitral valve prolapse. Methods. 151 patients (116 males and 35 females) with mitral valve prolapse (MVP) were examined. The average age was 34.8 ± 0.79 years. Division by the groups was performed depending on the severity of structural changes of the valve and width of the cusps: group 1 included 54 patients with classic form of MVP (cusp width ≥5 mm), group 2 included 55 patients with cusp width ≥3 mm, group 3 included 42 patients with MV cusp width less than 3 mm. All patients underwent complex clinical functional examination of cardiovascular system. The state of systolic and diastolic cardiac function was assessed using stationary high-tech ultrasound scanner «Philips iE-33» (Philips, Holland) according to conventional technique with determination of standard heart parameters and calculation of intracardiac hemodynamic parameters. Echocardiography was performed on admission and 12 to 18 month later. Results. The study revealed that the most prominent changes of cardiohemodynamics and unfavorable disease course were observed in 72.2 % of patients with classic form of MVP (group 1). Patients with non-classic form of MVP (group 2) also had poor prognosis in 27.8 % of cases. Diagnostic criteria of poor prognosis of MVP according to echocardiography were determined: severe mitral regurgitation (degree ≥III), mitral valve cusp thickness during diastole over 6 mm, left ventricle dilation (EDS ≥ 60 mm; ESS ≥ 36 mm), left atrial dilation (anterior posterior size of LA ≥ 40 mm, LA volume ≥ 80 ml), mitral annulus dilation (diameter of MA ≥ 35 mm). Conclusion. Differences of functional state of the myocardium of left ventricle were revealed depending on the type of mitral valve prolapse caused by the severity of connective tissue dysplasia. In classic form of MVP more severe disorders of intracardiac hemodynamics were observed as well as more severe mitral insufficiency.

Assessment of left ventricular contractile performance from isovolumic relaxation phase in man.

The rate of left ventricular (LV) pressure fall (dP/dtmin) is reportedly altered by contractility and LV stress. To explore the possibility that the ratio of dP/dtmin to dicrotic notch pressure (DTES) measures contractility, 243 subjects including 23 normals (group I) were studied. In 35 patients of group II (16 with mitral stenosis, 7 with atrial septal defect, and 12 with cor pulmonale) DTES, as an index of contractility (Cy Ix) measuring force-velocity-length relationship, was insignificantly different from group I (DTES and Cy Ix in group I = 21.6 +/- 0.6 s-1 and 1.34 +/- 0.04 muscle lengths/s/cm and 18.8 +/- 1.8 s-1 and 1.55 +/- 0.24 muscle lengths/s/cm in group II, respectively). With significantly reduced Cy Ix (1.05 +/- 0.04, p less than 0.01), DTES was likewise reduced (19.0 +/- 0.5, p less than 0.01) in 163 patients with compensated LV disease (47 with alcoholic cardiomyopathy, 24 coronary artery disease, 48 valve disease, 10 hypertensives and 34 with other heart muscle diseases). Like the Cy Ix (0.70 +/- 0.05, p less than 0.001), DTES was even lower (13.3 +/- 0.6, p less than 0.001) in 15 patients with decompensated LV (group IV). Like Cy Ix, this ratio changed significantly with acute changes in inotropy (exercise and pacing), but not with preload (dextran infusion). Basal heart rate, preload and afterload did not influence DTES. Furthermore, DTES correlated significantly in all groups and subgroups with two indices of contractility, VCE (velocity of contractile element) at peak isometric stress, and Cy Ix (r = 0.68 and 0.70, respectively, each p less than 0.001) measured in this study. These results indicate that DTES provides a simple, reliable, and useful measure of the contractile state of LV myocardium in man, independent of preload and afterload.

Contractile state of the left ventricle in man as evaluated from end-systolic pressure-volume relations.

End-systolic pressure (PES), volume (VES), wall tension (TES) and circumference (CES) of the human left ventricle were studied at cardiac catheterization in 24 subjects with varying degrees of left ventricular dysfunction. Acute alterations in systolic load consistently resulted in changes in VES and CES, with a smaller volume and circumference characterizing the lower systolic load in each subject. End systolic pressure-volume lines were constructed by plotting PES against VES at the higher and lower systolic load in each subject. The slope of the resultant lines was considerably steeper for normal than for poorly contractile left ventricles. Vo, the volume axis intercept of the line (i.e., the theoretical VES at PES = O) was significantly smaller for normal than for poorly contractile ventricles. Similar findings were noted for Co, the theoretic end-systolic circumference at zero end-systolic ventricular wall tension. Post-extrasystolic potentiation resulted in decreased VES and CES with no change in PES and only a slight fall in TES. In conclusion, end-systolic pressure-volume and tension-circumference relations reflect the contractile state of left ventricular myocardium. Quantitation of these relationships may provide a useful new approach to the assessment of myocardial function in man.