Based On Ultrasound To Research The Relationship Between Left Ventricular Diastolic Dysfunction And Hypocalcemia In Patients With Chronic Kidney Disease

Background and ObjectivesEarly in patients with Chronic kidney disease (CKD) have left ventricular diastolic dysfunction, and the occurrence rate is high. Left ventricular diastolic dysfunction in patients with CKD is caused by a variety of complicated factors. Left ventricular diastolic dysfunction and disorder of calcium and phosphorus metabolism are closely related. Studies have reported between altered Ca-P metabolism and blood cell morphology and myocardial function and arterial bed function, including coronary vessels. The biochemical level in patients with CKD disorders, including lower serum calcium levels and low levels of activation of vitamin D, hyperphosphatemia, these biochemical abnormalities affect the cardiovascular system, which will lead to the function of cardiovascular system disorder, the main reason is the calcium and phosphorus in sediments and arteriosclerosis. That has an important relationship between CKD and mortality and hyperphosphatemia, high calcium phosphorus product and high PTH. Nowadays, hyperphosphatemia is considered the most important biochemical disorders of uremia, leading to vascular calcification. Research shows that the essence of the calcification of the compound of calcium phosphate, and calcium phosphorus product is particularly important. In the complex metabolism of the CKD, the most direct impact of the hypocalcemia on the cardiovascular system still has not been studied, and a direct link between the low blood calcium and the cardiac function in patients with CKD still haven’t found. The purpose of this paper is to assess the potential effect of hypocalcemia in patients with CKD on left ventricular diastolic dysfunction by application of the echocardiography.Materials and methods1. Selected the left ventricular ejection fraction (EF)> 50%, CKD 2-5 stages of the 120 patients, hemodialysis patients, segmental wall motion abnormalities and other serious heart disease were excluded. All patients on admission were collected to age, gender, height, weight, heart rate and blood pressure, and carried out the conventional echocardiography and the tissue Doppler velocity imaging (TVI) examination in stable condition, to obtain the echocardiography parameters.2. Parameters of mitral annular early diastolic peak velocity (EmLV) as the standard to definite:left ventricular diastolic dysfunction is EmLV< 8cm/s and left ventricular diastolic function of normal is EmLV≥ 8cm/s. Divided into two groups according to the results of EmLV:left ventricular diastolic function in normal [diastolic function, DF (-)] group,68 cases, EmLV≥8cm/s; left ventricular diastolic dysfunction [DF (+)] group,52 cases, EmLV< 8cm/s, analyzed the differences between the two groups in general clinical and echocardiographic parameters.3. Collected laboratory parameters, including:serum creatinine (Scr), serum urea nitrogen (BUN), calcium (Ca), phosphorus (P) and parathyroid hormone (PTH), platelet count (PLT), hemoglobin (Hb) content, N-terminal B-type brain natriuretic peptide precursor (NT-proBNP), and calculated the glomerular filtration rate (GFR), analyzed the differences between the two groups of laboratory parameters.4. Selected the echocardiographic and laboratory parameters in the presence of the difference between the two groups, to calculate each parameter in diagnosis of left ventricular diastolic dysfunction of the area under the receiver operating characteristic curve, and the correlation analysis was carried out. Then selected the parameters of P<0.05 and carried out the multi factor regression analysis, analyzed the value of various parameters to predict the left ventricular diastolic dysfunction.Results1. Comparison of two groups of average data and laboratory parameters:the difference in age, gender, body mass index and CKD staging of the two groups had no statistical significance (P>0.05). DF (+) Ca level was reduced, there was significant difference between the two groups (P<0.001), while PTH and NT-proBNP levels (P=0.038 and P=0.014), the other parameters were not statistically significant.2. Comparison of two ultrasonic parameters:DF (+) group, ventricular septal thickness (IVSd) and left ventricular posterior wall thickness (LVPWd), left ventricular mass index (LVMI) increased, decreased E peak, E/A ratio decreased, and DF (-) group were statistically significant (P<0.05); DF (+) group peak systolic mitral annular velocity (SmLV) and EmLV decreased (P< 0.01), two groups of mitral annulus peak late diastolic velocity (AmLV) and there was no significant difference indifference (P=0.083).3. Statistical analysis of differences in laboratory and ultrasonic parameters of ROC curve are compared between the two groups:the construction of Ca ROC curve, the area under the curve was 0.745; according to the ROC curve showed that Ca<2.01mmol/L, the sensitivity in the diagnosis of left ventricular diastolic dysfunction was 95.5%, but its specificity was only 44.2%.4. There is correlation between ultrasound and laboratory parametersanalysis, statistical differences between the two groups:the analysis showed that there was significant negative correlation between LVMI, IVSd, LVPWd and EmLV (r=-0.249, P=0.006; r=-0.149, P=0.008; r=-0.372, P<0.001). Statistical significance between the two groups have the Ca, PTH and laboratory parameters of NT-proBNP and EmLV have good correlation (r=0.467, P<0.001; r=-0.211, P=0.011; r=-0.168, P=0.007).5. Multi factor regression analysis to predict left ventricular diastolic dysfunction in patients with CKD:influence factors on these analysis, the parameters, hypocalcemia (Ca≤2.01mmol/L) is considered as a relative sensitivity of prediction index of left ventricular diastolic dysfunction.ConclusionsHypocalcemia is a relative sensitivity of prediction index for left ventricular diastolic dysfunction in patients with CKD, which has a certain guiding significance to prevent and treat the left ventricular diastolic dysfunction in patients with CKD.