ABSTRACT
BACKGROUND: Contrast nephropathy is a common and often reversible cause of acute renal failure (ARF). About 10% of ARF in admitted patients might be due to it and may also lead to dialysis. Some methods could prevent it such as fluid therapy with half or normal saline, Na bicarbonate, N-acetyl cysteine (NAC), and so on. The aim of this study was to evaluate the efficacy of NAC to prevent contrast nephropathy. MATERIALS AND METHODS: In a cross-sectional study, 110 patients who were candidate for intravenous pyelography (IVP) or CT scan enrolled in two groups: Case and control. In patients of case group, meglumine compound and in control group, placebo was prescribed before procedure. Before study and after 48 h, blood urea nitrogen (BUN) and creatinine (Cr) was checked, and glomerular filtration rate (GFR) was measured with Cockcroft-Gault formula. RESULTS: There were no difference between age and gender of two groups. There was also no significant difference between mean Cr before and after study; however, GFR of patients in case group was significantly higher than the control group after 48 h of procedure. CONCLUSION: Because GFR was higher in case group and there were no drug side-effects in patients, we recommend the use of NAC before administration of intravenous contrast especially in high-risk population such as diabetic patients.
ABSTRACT
BACKGROUND: Atrial fibrillation (AF) after coronary artery bypass graft surgery (CABG) constitutes the most common sustained arrhythmia and results in prolonged hospitalization. The purpose of this study was to assess simultaneous right and left atrial pacing as prophylaxis for postoperative atrial fibrillation. METHODS AND RESULTS: From July 2003 to May 2004, 120 patients without structural heart disease and who underwent CABG were randomly classified into one of the following 3 groups: biatrial pacing (BAP), left atrial pacing (LAP), and no pacing (control). Atrial pacing was performed for 4 days. Post-CABG AF was significantly reduced in BAP group compared to single-site and control group (BAP, 17.5%; LAP, 30%; control, 45%; p=0.02). The mean length of hospital stay was significantly reduced in BAP group. Hospital charges were not significantly different between three groups. The mean length of hospital stay was most significantly reduced in BAP group (6.1+/-1.2 versus 9.0+/-4.1 days in the control groups; p=0.002, and 8.7+/-1.3 days in LAP groups; p=0.01). The mean length of stay in the intensive care unit was also significantly reduced in the BAP group (2.8+/-0.7 versus 4.6+/-4.5 days in control group; p=0.04, and 4.2+/-3.2 days in LAP group; p=0.01). CONCLUSIONS: Simultaneous right and left atrial pacing is well tolerated and is more effective in preventing post-CABG AF than single-site pacing, and, results in a shortened hospital stay. Identifying patients at risk for developing postoperative AF and using this prophylactic method may be the optimal effective strategy.
ABSTRACT
OBJECTIVE: This study was undertaken to demonstrate that transmyocardial laser revascularization of hypoperfused myocardium improves regional and global myocardial function. METHODS: Cine magnetic resonance imaging was used to monitor regional wall thickening (in millimeters) and cardiac output (in milliliters per kilogram per minute). Cine magnetic resonance imaging was performed before and 8 weeks after transmyocardial laser revascularization was applied to the hypoperfused lateral wall of the left ventricle (target area) in a porcine model (n = 9, transmyocardial laser revascularization group). A second group of animals was left untreated (n = 8, control group). RESULTS: Regional wall thickening in the target area improved after transmyocardial laser revascularization (0.7 +/- 0.3 mm to 3.7 +/- 1.9 mm, P <.02) and was significantly higher (P <.01) after transmyocardial laser revascularization than in the control group, in which it did not improve (0.5 +/- 0.6 mm to 0.5 +/- 1.2 mm). Accordingly, cardiac output and microsphere-derived myocardial blood flows were significantly higher than in the control group (P <.01), and the amount of triphenyltetrazolium chloride-stained myocardium was lower (P <.01). CONCLUSION: Cine magnetic resonance imaging demonstrates improved global and regional myocardial function after transmyocardial laser revascularization in a porcine model.
Subject(s)
Heart/physiology , Laser Therapy , Magnetic Resonance Imaging, Cine , Myocardial Revascularization/methods , Animals , SwineABSTRACT
OBJECTIVE: It is controversial whether transmyocardial laser revascularization (TMLR) improves myocardial perfusion. Therefore, we assessed myocardial perfusion before and after TMLR with quantitative magnetic resonance perfusion imaging (MRPI) in an animal study. METHODS: One week after partial occlusion of the left circumflex artery (LCx) in 12 pigs, resting perfusion (ml/g/min), perfusion reserve (PR) with adenosine, regional wall thickening (RWT), cardiac output (CO) were quantified with MRI in the LCx (lateral) and LAD (septal) dependent myocardium. Subsequently, six animals were treated with TMLR of the lateral left ventricle (LV). Six animals were left untreated. A final MR was performed 8 weeks later. MRPI data were compared to microsphere-derived blood flow and % LV necrosis (TTC). 'Normal' myocardial perfusion was assessed with MRPI in 12 non-instrumented animals. RESULTS: Resting perfusion prior to TMLR (0.7-0.9+/-0.3) in the LV-lateral myocardium was preserved after TMLR (1.0+/-0.3) and decreased without TMLR (0.3+/-0.1, P<0.05). There was a significant difference (P<0.01) between the TMLR treated and untreated group. Compared to 'normals' (1.2+/-0.2) perfusion of the LV-lateral wall was not different after TMLR but reduced (P<0.02) without TMLR. PR was not different between TMLR-treated (1.4+/-0.9) and untreated (1.9+/-0.6) group but was reduced (P<0.04) compared to PR of 'normals' (2.7+/-0.8). MRPI data and microsphere-derived perfusion were significantly correlated (P<0.01). RWT in the LCx-dependent myocardium improved (P<0.02) after TMLR. CO decreased (P<0.02) and TTC-staining indicated more LV-necrosis without TMLR (6.6+/-1.6 vs. 3.7+/-1.5, P<0.01). CONCLUSION: TMLR preserves regional myocardial perfusion and improves function as shown with MRPI.
