[Risk factors for failure of continuous veno-venous hemodialysis in the treatment of acute kidney injury following cardiac surgery].

OBJECTIVE: To evaluate the independent risk factors for failure of continuous veno-venous hemodialysis (CVVHD) in the treatment of acute kidney injury (AKI) following cardiac surgery. METHODS: Adult patients without any prior pre-operative history of chronic renal disease suffering AKI following cardiac surgery and undergoing CVVHD at our center from January 2005 to December 2012 were recruited and divided into either a success group or a failure group. All pre-, intra- and post-operative data were collected and retrospectively analyzed. RESULTS: Ninety-three adult patients were enrolled. Among them, sixty-three patients survived with a failure rate of 32.2% and a mortality rate of 19.4%. Through univariate analysis and multivariate Logistic regression, independent risk factors for failure of CVVHD in the treatment of post-operative AKI included pre-operative LVEF (OR = 0.61, 95%CI 0.42-0.85) and duration of oliguria until dialysis (OR = 2.76, 95%CI 1.51-5.83). CONCLUSION: Pre-operative impaired left ventricular function is an important risk factor for failure of CVVHD in the treatment of AKI after cardiac surgery. The sooner the implementation of CVVHD, the better prognosis.

[Coronary flow obstruction in percutaneous aortic valve replacement using self-expandable valved stent: an in vitro study].

OBJECTIVE: To study the effects of self-expandable and orthotopically implanted percutaneous aortic valved stent on coronary artery flow in vitro. METHODS: Self-expandable valved stent was developed with nitinol stent and bovine pericardium. The ascending aorta of Chinese mini swine hearts was cut proximal to the brachiocephalic trunk. The right and left main coronary arteries were dissected. In vitro coronary flow tests were performed. Firstly, baseline coronary flow with the native aortic valve was measured (n = 12). Secondly, the valved stent was deployed orthotopically. The commissures of prosthesis were positioned randomly. Through an endoscope, the effects of valved stent and native valve on coronary ostium were obtained and coronary flow measurements repeated (valve preservation group, n = 12). Then the distance from coronary ostium to native leaflet free edge was measured. Native leaflets were removed before similar valved stent deployment. Coronary flow measurements and endoscopic inspections were repeated post-implantation (valve removal group, n = 12). RESULTS: In valve preservation group, valved stent implantation resulted in a significant decrease in left coronary flow (29.46%, P < 0.05). The obstruction was due to native leaflets sandwiched between the stent and aortic wall. The left ostia were obstructed totally in 3 and partially in 4. The flow of right coronary decreased 7.34% (P > 0.05). The right ostia were obstructed partially in 3. In valve removal group, 6.82% and 5.37% decrement in left and right coronary flow were observed after valved stent placement (P > 0.05). The distances from right coronary ostia to annulus were farther than from left coronary ostia. In two groups, the commissures of prosthesis obstructed partially left coronary ostia in 4 and right coronary ostia in 1. CONCLUSION: Orthotopic implantation of a percutaneous self-expandable aortic valved stent would obstruct the left coronary ostium with the native valve. Coronary ostium may be obstructed partly by the commissures of prosthesis.

[Effect of atorvastatin on postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting].

OBJECTIVE: To evaluate the effect of atorvastatin on postoperative atrial fibrillation (AF) in patients undergoing coronary artery bypass grafting (CABG). METHODS: A cohort of 140 consecutive patients without a history of documented AF or previous statin use, who were scheduled to undergo selective CABG, were enrolled. Included patients were randomly assigned to atorvastatin group (n = 71) who were administered atorvastatin 20 mg/d or to control group (n = 69). After CABG, subjects were monitored continuously by electrocardiographic monitors at least 7 days. During the initial postoperative 7 d, the incidence and duration of AF were recorded. And the levels of high-sensitivity C-reactive protein (hs-CRP) were measured before and 24 hours, 72 hours, 7 days after operation, respectively. The statistical software package SPSS (version 13.0) were used to analyze the data. The differences between groups were evaluated by chi(2)-test for discrete variables and student t-test for continuous variables. Multivariate logistic regression analysis was performed to determine the independent predictors of early postoperative AF. RESULTS: During initial postoperative 7 d, AF occurred at least once in 10 cases in atorvastatin group, with a prevalence of roughly 14%, and in 23 cases in control group, with a prevalence of approximately 34% (P = 0.009). The mean duration of single AF was 3.6 +/- 0.4 hours in atorvastatin group and 5.7 +/- 0.5 hours in control group (P < 0.01), respectively. The multivariate logistic analysis showed that perioperative atorvastatin administration was an independently risk factor for early postoperative AF (OR = 0.219, 0.076-0.633, P = 0.005). There was also statistical difference in hs-CRP after CABG between the two groups. CONCLUSIONS: Perioperative atorvastatin administration may inhibit inflammatory reaction, reduce the incidence and duration of postoperative AF, hence may prevent and treat postoperative AF.

[Opportunity for treatment of acute renal failure after cardiac vascular operation using continuous blood purification].

OBJECTIVE: To evaluate the effect and timing of continuous blood purification (CBP) in treatment of acute renal failure (ARF) following cardiac-vascular surgery. METHODS: Twenty-five patients with ARF following cardiac-vascular surgery were divided into systematic inflammatory response syndrome (SIRS) Group (n = 13) and multiple organ dysfunction syndrome (MODS) Group (n = 12) according to the illness state prior to CBP and were divided into Group A (n = 5, with the APACHEIII score prior to CBP 90). All of the 25 patients underwent continuous veno-venous hemofiltration (CVVH). Before and 24h after the CVVH APACHEIII score was calculated and [peripheral; blood samples were collected to detect the levels of blood urea nitrogen (BUN) and serum creatinine (Scr) and the plasma levels of interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha). RESULTS: The APACHEIII score, BUN, Scr, IL6, IL8, and TNFalpha 24 h after the CBP of the 25 patients were 61 +/- 15 mmol/L, (19 +/- 5) mmol/L, (312 +/- 87) micromol/L, (544 +/- 154) ng/L, (18 +/- 7) ng/L, and (43 +/- 15) ng/L respectively, all significantly lower than those before CBP (81 +/- 20, 26 +/- 5 mmol/L, 458 +/- 107 micromol/L, (842 +/- 132) ng/L, (25 +/- 8) ng/L, and (59 +/- 17) ng/L respectively, all P = 0.000). The survival rate of SIRS Group was 84.62%, significantly higher than that of MODS Group (41.67%, P < 0.05). The APACHEIII score, and the levels of BUN, Scr, IL6, IL8, and TNF-alpha of Group MODS were significantly higher than those of Group SIRS. The higher the level of Scr, IL6, IL8, and TNF-alpha and the APACHEIII score the lower the survival rate. CONCLUSION: CBP has a positive effect on ARF following cardiac-vascular surgery. The APACHEIII score 60 to 90 reflects an opportunity to treat the ARF following cardiac-vascular surgery using CBP.

[Influence of pravastatin on blood lipids and serum high sensitive C-reactive protein in patients undergoing conventional coronary artery bypass grafting under on-pump: a clinical study of 81 cases].

OBJECTIVE: To investigate the effect of pravastatin on blood lipids and serum high sensitive C-reactive protein (HsCRP) in patients undergoing conventional coronary artery bypass grafting under on-pump bypass (CCABG). METHODS: Eighty-one patients underwent CCABG. Among which 40 took orally pravastatin 20 mg once daily to at least 28 days after operation, and 41 were used as control group. The serum levels of total cholesterol (TC), triglyceride (TG), HDL-C cholesterol (HDL-C), LDL-C cholesterol (LDL-C), and HsCRP were monitored before and 24 h, 72 h, 7 days, 10 days, 14 days, and 28 days postoperatively. RESULTS: In the control group the levels of different blood lipids after operation remarkably decreased after operation compared with those before operation (all P < 0.05), reached the lowest levels 24 h after operation, then gradually increased, however, still lower than those before operation (all P < 0.05), and recovered to the baseline level 28 hours after operation; and the HsCRP level increased 24 h after operation and peaked 72 h after, then gradually decreased, and recovered to the baseline level 28 days after operation. In the pravastatin group the TC level reached its lowest level 24 h after operation, then gradually increased, however, still lower than that before operation, and recovered to the baseline level 28 days after operation; and the TG level reached the lowest level 24 h after operation (P < 0.05), and then gradually increased 3 d after operation (P > 0.05). The TC, TG, and LDL-C levels 7, 10, 14, and 28 d after operation of the pravastatin group were all significantly lower than those of the control group (all P < 0.05). The HsCRP levels at different time points of the pravastatin group were all significantly lower than those of the control group (all P < 0.05). CONCLUSION: The use of pravastatin in the early stage of CCABG is safe and can decrease systemic inflammatory reaction.

[Combined use of transmyocardial stents with gene therapy in the treatment of acute myocardial infarction].

OBJECTIVES: To determine the efficacy of combined use of transmyocardial stent with gene therapy to treat acute myocardial infarction in porcine model. METHODS: 24 Chinese mini swines have been divided into 4 groups randomly: group myocardial infarction (group MI n(1) = 6), group transmyocardial stent (group ST n(2) = 6), group vascular endothelial growth factor (group VEGF n(3) = 6), group transmyocardial stent and VEGF (group ST + VEGF n(4) = 6). In group MI, acute myocardial infarction animal model has been established by the ligation of the left descending coronary artery. In group ST, after the establishment of the model, 3 transmyocardial stents were implanted. In group VEGF, an expression plasmid containing the gene-encoding VEGF(165) (300 microg) was administered directly in the myocardium at 6 sites. In group ST + VEGF, both transmyocardial stents and expression plasmid containing the gene-encoding VEGF(165) are applied. 4 weeks later, the animals are sacrificed and echocardiography and pathological analysis have been done. RESULTS: The density of blood vessel in group ST, VEGF and ST + VEGF are significantly higher than group MI. And capillary density in group ST + VEGF is the highest in these groups statistically. Expression of VEGF was detected in group ST, VEGF and ST + VEGF, but in group VEGF and ST + VEGF the level of expression are higher. CONCLUSION: Combined use of transmyocardial stent with gene therapy has synthetic effect for the treatment of acute myocardial ischemia in porcine model and can significantly increase the vascular density.