Clinical Research Of Ischemic Nephropathy And Contrast-induced Nephropathy

Part 1The Clinical Study Of Atherosclerotic Renal Artery Stenosis And Acute Coronary Syndrome acompanied Acute Left Heart FailureBackground Atherosclerosis is a diffuse process affecting the vascular system and may results in different clinical syndromes due to dysfunction of more than one organ in the same patient. With the development of coronary angiography and stenting, more and more renal artery stenosis (RAS) were diagnosed. Significant RAS has been reported to occur in up to 29% of patients with CAD undergoing coronary angiography. Association between either peripheral vascular disease or carotid artery disease with coronary artery disease (CAD) is well recognized. More recently, the association of renovascular disease with CAD especially acute coronary syndrome (ACS)has been emphasized, some of them acompanied with acute left heart failure (ALHF). Compared with ACS and ALHF easily diagnosed, RAS is a entity extensively overlooked because of lack of typical symptoms or its symptoms covered by other diseases. Besides traditional drugs therapy, renal artery revascularization (mostly stenting) has been utilized in clinical practice. But the combination of ACS and RAS companied with ALHF, making things compound, is closely related to the improvement of blood pressure control, preservation of cardinal and renal function, incidence of major adverse cardinal event,and long-term prognosis. At present, the studies and evidence about this continually increasing clinical settings are relatively absent, and the incidence, clinical characteristics, diagnostic clues, most reasonable therapeutic strategies and prognosis remains unclear.Aim To explore the incidence, clinical characteristics, diagnostic clues, relationship between therapeutic strategies and prognosis of the triad, and to improve the diagnostic rate and therapeutic effect.Objectives and Methods The study was retrospective, non-randomized, observational. Clinical data of enrolled 104 cases were collected, including the general information, diagnostic clue, therapeutic strategies, outcome of post procedure and follow-up. Cut-off point was defined as the moment of diagnosis of RAS according to selective renal arterigraphy. All cases were defined as two groups, group of ALHF and non-ALHF, according to the onset of ALHF or not. The clinical data were compared between two groups By t test or x2 test.Results Mean age of all patients was 70.65±9.75 years,79(76.0%)of them were male. The incidence of diabetes mellitus, dislipidemia, post or present smoking, old myocardial infarction, cerebrovascular accident, peripheral vascular disease was 41(39.4%),26(25.0%),39 (37.5%),33(31.7%),44(42.3%),32(30.8%) separately; hypertention and renal dysfunction presented in 90 (86.5%) and 38(36.5%)cases respectively.34(32.7%) cases of 104 occurred ALHF at the moment of cut-off moment and were defined as ALHF group, the others non-ALHF group. Of all patients, mean period of confirmation of CAD-comfirmation of RAS was 49.8±81.33 months; the mean number of stenostic renal and coronary artery was1.47±0.45 separately; coronary stenting or CABG or hybridiration was taken for all patients, while non-stenting, unilateral, bilateral stenting in renal artery was 17(16.3%), 68(65.4%),19(18.3%) respectively.5 cases of 104 died after the procedure,3 cases in ALHF groups; 40 cased of 104 occurred MACE within the follow-up period. Compared with non-ALHF group, the rates of blood pressure control and preservation of renal function were low in ALFH group(P=0.000 and 0.003 respectively), and cases of ALHF group suffered from more MACE [23(67.6%)vs22 (31.4%)P=0.000)].Conclusions The prevalence of ALHF presented higher in patients of combination of RAS and ACS, and RAS was often overlooked while CAD or ACS was diagnosis, leading to relatively higher incidence of ALHF and worse prognosises. Earlier diagnosis and treatment of RAS is good for control of renovascular hypertension, preservation of renal function, avoiding or postponing onset of ALHF, reducing MACE and improving long-term prognosis; further prospective research is needed for the best strategies of the complexity. Part 2The Clinical Research Of Implication Of Urine Neutrophil Gelatinase-associated lipocalin (NGAL) In Early Diagnosis Of Contrast-Induced Nephropathy After Coronary AngiographyBackground Acute kidney injury(AKI), including contrast-induced nephropathy (CIN), is a frequent and serious complication of hospitalized patients associated with substantial morbidity and mortality. several interventions for AKI have been proved ineffective. This failure is caused in part by the lack of real-time sensitive and specific renal biomarkers to allow the early diagnosis of impending AKI. Serum creatinine (SCr)level and urine output are the most frequently used indicators of renal dysfunction despite their known limitations. T Early detection of AKI could permit the institution of timely renal salvage therapies, which, with associated monitoring of response to therapy, may result in preserved renal function and avoidance of renal replacement therapy requirement and perhaps translate into improved patient morbidity and mortality. Researches have identified NGAL as an early marker of AKI. In experimental and clinical studies, NGAL has been investigated extensively and would appear to be one of the most promising early biomarkers of AKI. NGAL has been investigated across a range of different clinical settings of AKI, such as after cardiac surgery, in critically ill patients, in patients receiving intravenous contrast media infusion for coronary angiography, and in patients admitted to the emergency department. It also has been studied in both adult and pediatric populations, and has been measured in urine and plasma/serum Present research results show NGAL performs well in the early diagnosis and prognosis judgment of CIN, both urine and serum sample. NGAL is detected firstly in urine within a few hour after the insult happens or infusion of contrast through vessel in artery intervention. And is a promising early diagnosis of biomarker due to be non-invasive and easy to get sample. But some concerns arose such as the stability of the biomarker,race difference, the convenience of clinical utilization, and the timing of rapid diagnosis. Another problem is the concentration of NGAL is influenced by the infusion and intake of liquid and the volume of urine But relative research is seldom found in the present study,although volume of body fluid and urine play a important role.Aim To explore the implication of urine NGAL in early diagnosis of CIN after coronary angiography in a prospective study, and the influence of body liquid and urine volume for NGAL concentration.Objectives and Methods Eighty patients undergone coronary angiography with at least one risk factor of CIN were enrolled in this study. Clinical data were collected of all enrolled patients. The concentration of serum creatinine (SCr was tested by enzymic method) before and 48h after the procedure were measured and CIN was defined following the traditional criteria. All patients were divided two groups, the group of CIN and non-CIN according to the incidence of CIN. to Before and 2h after the procedure,the urine samples were collected and the concentration of NGAL, creatinine and albumin were tested separately by ELISA and enzymic method. All data were compared between CIN and non-CIN groups. SPSS version16.0 was used for analyses. To compare continuous variables, we used a two-sample t test, and to compare categorical variables we used the x 2 or Fisher's exact test, as indicated. To measure the sensitivity and specificity for urine and NGAL at different cut-off values, a conventional receiver-operating characteristic (ROC) curve was generated for urine NGAL at 2 h after the procedure and the incidence of CIN. We calculated the area under the curve to ascertain the quality of NGAL as a biomarker.Results The mean age of all cases was 67.67±13.84 years, baseline evaluated glomerular filtration ratio 74.46±27.23 ml/min/1.73m2; the mean volume of contrast infused was 180.78±90.62 ml, with baseline and 48h post the procedure SCr separately 107.11±68.68 and 119.65±89.37(P=0.003)μmol/L. The baseline and 2h post the procedure urine creatinine were 7.67±7.25 and 3.61±3.10 mol/L (P=0.000) and the urine albumin 12.36±42.87 and 15.38±79.23mg/dL (P=0.552), urine NGAL 36.1887±59.78 and 29.56±50.38ng/L(P=0.272). The corrected urine NGAL 2h post procedure by baseline/urine creatinine 2h post procedure was 55.256±83.35 ng/L, and there was significant difference compared the baseline urine NGAL (P=0.044). CIN occurred 15 cases of 80 enrolled patients, the incidence was 18.8%. In baseline data, compared with non-CIN groups, CIN group displayed no significant difference except admitted renal dysfunction. The urine NGAL level(ng/L) of 2h post contrast infusion of CIN group elevated significantly compared to the non-CIN group (77.29±88.02 vs18.55±27.94; P=0.000), although the mean urine NGAL of 2h post procedure of all cases was a little decreased than the baseline level(36.19±59.78 VS29.56±50.38; P=0.272, no significant difference). ROC analysis confirmed the early diagnostic accuracy of 2h post procedure urine NGAL in CIN, and the area under the curve was 0.741 (SD 0.0667,95% CI 0.630-0.832, P=0.0003). With the cut-of value of NGAL as 20.19 ng/L, the diagnostic sensitivity and specificity in CIN were 80% and 56.6%, respectively. Conclusions Urine NGAL can diagnose CIN earlier than SCr, which could be a good biomarker for early diagnosis of CIN, but was influenced by the body fluid and urine volume; further study and evaluation is necessary.