Coronary slow flow phenomenon: Not only low in flow rate but also in myocardial energy expenditure.

BACKGROUND AND AIM: Coronary slow flow phenomenon (CSFP) is a miscellaneous clinical entity leading to angina-like symptoms, and electrocardiographic and scintigraphic evidence of ischemia. The impact of this syndrome on myocardial performance has not been comprehensively evaluated. In this study, we sought to evaluate the myocardial energy expenditure (MEE) in patients with CSFP and its relationship with exercise capacity. METHODS AND RESULTS: A total of 64 patients (64.1% male, mean age 53.2 ± 10.3 years) with CSFP and 64 patients (60.9% male, mean age 52.2 ± 10.9 years) with normal coronary artery as control group were included. MEE was calculated by a validated formula that uses transthoracic echocardiography (TTE) parameters, including left ventricular circumferential end-systolic stress, stroke volume, and ejection time CSFP patients had significantly lower MEE (0.79 cal/systole ± 0.15 vs. 0.91 cal/systole ± 0.09, p < 0.001). In correlation analysis, MEE had a significant negative correlation with mean corrected TIMI frame count (mTFC) (ß = -0.523; p < 0.001) and positive correlations with metabolic equivalents (METs) (ß = 0.560; p < 0.001), rate pressure product (ß = 0.649; p < 0.001), and exercise duration (ß = 0.408; p < 0.001). At multivariate analysis, MEE was demonstrated as an independent predictor of CSFP (OR 1.863, CI 95% 1.485-2.338 p < 0.001). CONCLUSION: Myocardial energy consumption, as a calculation obtained from TTE parameters, was reduced in patients with CSFP, and it had a significant relationship with exercise capacity. Considering its significant correlation with exercise capacity, myocardial energy consumption seemed to use evaluation of myocardial performance and functional status in another cardiovascular disease.

Right ventricular outflow tract function in chronic obstructive pulmonary disease.

BACKGROUND: It is clinically important to evaluate the severity of right ventricular (RV) overload in patients with chronic obstructive pulmonary disease (COPD), which is often associated with changes in the structure and the function of the right ventricle. Noninvasive and reliable assessment of RV function would be an essential determinant of RV load and a clinically useful factor for assessing cardiovascular risk in COPD patients. OBJECTIVE: The aim of this study was to investigate the clinical application value of right ventricular outflow tract (RVOT) systolic function measured by transthoracic echocardiography in patients with COPD. PATIENTS AND METHODS: We prospectively investigated COPD male patients and compared them with healthy controls. In addition to RV conventional echocardiographic parameters, RVOT size and fractional shortening (RVOT-FS) parameters were also assessed. RESULTS: Fifty-five COPD patients (all men; mean age, 62 ± 9 years) participated in the study, and were compared with a control group consisting of 21male, healthy, nonsmoking subjects with a mean age of 58 ± 11 years. The RVOT-FS was impaired in COPD patients than healthy controls (27.8 ± 15.5 vs. 57.5 ± 8.6, p < 0.001), and was correlated positively with tricuspid annular plane systolic excursion (TAPSE; r = 0.583, p < 0.001) and pulmonary acceleration time (r = 0.666, p < 0.001) and inversely with pulmonary artery systolic pressure (r = 0.605, p < 0.001) and functional capacity(r = - 0.589, p < 0.001). There was a statistically significant difference in RVOT-FS among the COPD subgroups with regard to New York Heart Association functional classification (p < 0.001). CONCLUSION: The RVOT-FS is a noninvasive easily applicable measure of RV systolic function and is well correlated with functional capacity in COPD patients. Its combination with long-axis measurements via TAPSE and transtricuspid Doppler analysis may provide a comprehensive evaluation of the RV performance in COPD patients.

Association of epicardial fat thickness with TIMI risk score in NSTEMI/USAP patients.

BACKGROUND: The association of epicardial adipose tissue (EAT) with coronary artery disease has been shown in previous studies. Furthermore, the relationship between EAT and acute coronary syndrome was studied recently. Herein, we investigated the relationship between EAT thickness and the thrombolysis in myocardial infarction (TIMI) risk score for non-ST-elevation myocardial infarction (NSTEMI) and unstable angina pectoris (USAP). PATIENTS AND METHODS: The study included 144 patients with NSTEMI/USAP. The study population was divided into two subgroups according to TIMI risk scores as group I (≤ 4, n = 86) and group II (> 4, n = 58). Stepwise multivariable logistic regression analysis was used to assess the independent association of clinical parameters with TIMI risk score. RESULTS: EAT thickness was higher in group II than in group I (8.2 ± 2.1 vs. 6.2 ± 2.2, p < 0.001). Moreover, patients in group II had higher rates of multivessel disease and Gensini score (p < 0.001). In univariate linear regression analysis, EAT was positively correlated with TIMI risk score and Gensini score. Multivariate regression analysis showed that EAT thickness (OR: 1.56, 95 % CI: 1.17-2.08, p = 0.003), LVEF (OR: 0.93, 95 % CI: 0.85-0.98, p = 0.03), and Gensini score (OR: 1.36, 95 % CI: 1.24-1.98, p = 0.002) were independently associated with a higher TIMI risk score. CONCLUSION: In conclusion, EAT thickness is independently associated with TIMI risk score and may be an emerging risk factor for adverse events in NSTEMI/USAP patients.

Intensive pulmonary care after liver surgery: a retrospective survey from a single center.

BACKGROUND: Prevention from postoperative pulmonary complications (PPCs) has been an important topic. The aims of this study were to determine the risk factors for PPC after liver surgery and to analyze the efficacy of postoperative pulmonary care on PPC prevention. MATERIALS AND METHODS: We retrospectively analyzed variables of 81 patients who underwent hepatectomy and 4 transplantations between January 2007 and March 2012. RESULTS: Nineteen patients suffered PPCs (22.4%). Bivariate analysis identified four risk factors: preoperative anemia (odds ratio [OR] = 5.69), the American Society of Anesthesiologists (ASA) score of 3 or 4 (OR = 5.36), blood transfusion (OR = 2.81), and prolonged operative time (OR = 1.01). Upon multivariate analysis, only prolonged operative time was an independent risk factor for PPC (OR = 1.01). Pulmonary function test (PFT) was performed for 22 of 41 patients with an ASA score ≥ 2 (53.7%); there was no significant relationship between abnormal PFTs (n = 13) and the development of PPCs (P = .12). CONCLUSIONS: The elimination of risk factors may reduce the incidence of PPCs. Postoperative intensive pulmonary care should be given to all patients after liver surgery but particularly to patients with high ASA scores and those with abnormal PFTs irrespective of age.

Hepatic microcirculation in inflow and inflow-outflow occlusion of the liver.

BACKGROUND: Total vascular exclusion (TVE) causes warm liver ischemia. The aim of this study was to investigate the patterns of injury caused by inflow-outflow obstruction in the rat liver. MATERIALS AND METHODS: Twenty-four Wistar-Albino rats were divided into three groups: liver inflow occlusion (Group A), inflow-outflow occlusion (Group B) and intermittent inflow-outflow occlusion applied for 15 minutes. Microcirculation was measured with laser Doppler flowmetry during the procedure. Samples for biochemical and histopathological analyses were collected at the end of the ischemia period. RESULTS: Significant alterations in microcirculation were determined by application of vascular control maneuvers. Microcirculation in the central and dome segments were affected adversely compared with the dome segments in all experimental groups. TVE induced severe disturbances in hepatic microcirculation with more prominent hepatocellular damage. Damage to central segments of the rat liver was more prominent with inflow occlusion; whereas inflow-outflow occlusion produced more prominent damage to dome segments. Intermittent application of TVE clamping was associated with more hepatocellular damage compared with continuous TVE. CONCLUSION: Our mapping methodology within the liver parenchyma suggested that hepatovenous back-perfusion is a principle source of continuity of microcirculation in the rat liver during inflow occlusion. Inflow-outflow occlusion caused more tissue damage compared with inflow occlusion. Ischemic preconditioning during TVE did not increase the tolerance of the liver against ischemia.

Optical properties of heavily doped GaAs nanowires and electroluminescent nanowire structures.

We present GaAs electroluminescent nanowire structures fabricated by metal organic vapor phase epitaxy. Electroluminescent structures were realized in both axial pn-junctions in single GaAs nanowires and free-standing nanowire arrays with a pn-junction formed between nanowires and substrate, respectively. The electroluminescence emission peak from single nanowire pn-junctions at 10 K was registered at an energy of around 1.32 eV and shifted to 1.4 eV with an increasing current. The line is attributed to the recombination in the compensated region present in the nanowire due to the memory effect of the vapor-liquid-solid growth mechanism. Arrayed nanowire electroluminescent structures with a pn-junction formed between nanowires and substrate demonstrated at 5 K a strong electroluminescence peak at 1.488 eV and two shoulder peaks at 1.455 and 1.519 eV. The main emission line was attributed to the recombination in the p-doped GaAs. The other two lines correspond to the tunneling-assisted photon emission and band-edge recombination in the abrupt junction, respectively. Electroluminescence spectra are compared with the micro-photoluminescence spectra taken along the single p-, n- and single nanowire pn-junctions to find the origin of the electroluminescence peaks, the distribution of doping species and the sharpness of the junctions.

Routine intraoperative aspiration of gallbladder during laparoscopic cholecystectomy.

BACKGROUND: Technical modifications and methods for gallbladder dissection to minimize the risk of gallbladder perforation during laparoscopic cholecystectomy (LC) are described. The authors aimed to investigate the effects of gallbladder aspiration during LC on the operative and postoperative course of patients. METHODS: For this study, 200 patients undergoing LC for symptomatic cholelithiasis were randomly divided into two groups. Gallbladders were aspirated before dissection in group A (n = 100), and they were not aspirated in group B (n = 100). Operative and postoperative data on the patients were collected. RESULTS: The rate of gallbladder perforation was significantly lower in group A than in group B (p = 0.0003). The operative time was significantly shorter in group A (46.70 +/- 15.93 min) than in group B (60.75 +/- 22.09 min) (p = 0.047). Postoperative complications were more numerous in group B. The hospital stay was significantly longer in group B (1.55 +/- 0.81 days) than in group A (1.3 +/- 0.5 days; p = 0.004). CONCLUSION: The findings demonstrate the advantages of gallbladder aspiration in elective cases.

Heterogeneity of damage between segments of rat liver after inflow-outflow obstruction.

BACKGROUND: Total vascular exclusion (TVE) causes warm liver ischemia. The complete explanation of the events during inflow and outflow obstruction of the liver during selective TVE has not yet been studied. The aim of this study was to investigate the liver injury caused by inflow-outflow obstruction in the rat liver. MATERIALS AND METHODS: Forty Wistar-Albino rats were divided into four groups. Liver inflow occlusion (groups A and C) or inflow-outflow occlusion (groups B and D) was applied for 30 minutes. Samples were collected at the end of the ischemia period. We examined oxidative injury in the liver tissue and liver histopathology. RESULTS: Oxidative stress and histopathologic alterations were more prominent with TVE application. Significant alterations were shown in hepatic superoxide dismutase, glutathione, and glutathione S-transferase levels. Central segments of the rat liver were affected significantly from inflow occlusion, whereas dome segments were significantly damaged from inflow-outflow occlusion. CONCLUSIONS: Inflow-outflow occlusion of the liver caused more tissue damage compared with inflow occlusion. The pattern of distribution of the damage due to TVE seemed different from other well-known ischemia-reperfusion injuries.

Brugada-like early repolarisation pattern associated with acute pericarditis.

Two cases of acute pericarditis presented with interesting electrocardiograms resembling Brugada-like or early repolarisation patterns. This report emphasises that proper interpretation of the electrocardiogram in patients with ST-segment elevation assists the clinician in arriving at the correct diagnosis in making appropriate diagnostic and therapeutic decisions, and also that the saddleback-type ST-segment elevation cannot be a sensitive finding for the Brugada syndrome.

Bilateral renal lymphangiomatosis mimicking hydronephrosis: multidetector CT urographic findings.

Renal lymphangiomatosis is a very rare disorder, with only a few reported cases. We present a case of bilateral renal lymphangiomatosis, manifested by bilateral flank pain, that was falsely diagnosed as hydronephrosis. Excretory urographic, ultrasonographic, and computed tomographic urographic findings are described.

Evaluation of liver damage after application of TVE in the rat model.

INTRODUCTION: The aim of this study was to investigate the effects of total vascular exclusion (TVE) on the liver during the early period of reperfusion. MATERIALS AND METHODS: Forty Wistar-Albino rats were divided into four groups. Portal pedicle clamping (groups 1 and 2) or TVE (groups 3 and 4) were applied for 10 minutes. Samples were collected at the time of clamp release (groups 1 and 3) and at 30 minutes of reperfusion (groups 2 and 4). We examined oxidative injury to and histopathology of the liver. RESULTS: Oxidative stress was more prominent with TVE application. Significant alterations were shown in hepatic superoxide dismutase, catalase, glutathione, and glutathione S-transferase levels. The levels of malondialdehyde and myeloperoxidase were not altered significantly. CONCLUSION: Inflow-outflow occlusion of the liver causes more oxidative stress compared with inflow occlusion.

The effects of dimethyl sulfoxide on liver damage caused by ischemia-reperfusion.

INTRODUCTION: The aim of this study was to investigate the effects of dimethyl sulfoxide on liver damage caused by ischemia-reperfusion after portal vein clamping. MATERIAL AND METHODS: Forty New Zealand rabbits were divided into three groups with the portal veins of all the rabbits except the sham group clamped for 30 minutes: group I, sham procedure; group II, control group; and group III, 500 mg/kg DMSO. The drug was administered IM in the left inguinal region 30 minutes before the operation. Blood samples (5 mL) were taken from the animals at 15, 30, and 45 minutes. At the end of the experiment 1 g of liver tissue samples were obtained. Malondialdhyde (MDA), nitric oxide (NO), AST, ALT, and LDH plasma levels were measured in the blood samples. Liver tissue samples stained with hematoxylin eosin were examined under light microscopy for histopathological changes. FINDING: The liver enzymes in both clamping groups increased significantly compared with the sham group (P < .01). Enzyme levels of the DMSO group decreased significantly compared to the control clamping group (P < .05). Similar to the enzyme changes, MDA and NO levels increased in the portal vein clamping versus the sham group and decreased in the drug-administered group versus the control clamped group (P < .03). The severity of histopathological changes was less in the DMSO group than in the clamped controls. CONCLUSION: DMSO decreased the severity of liver damage after portal vein clamping.

Diaphragmatic herniation after transhiatal esophagectomy.

Increasing experience with transhiatal esophagectomy (THE) has brought with it a good understanding of the advantages and disadvantages of the technique. As in our case, diaphragmatic hernias after THE may result from excess manipulation and extension of the hiatus during surgery. The varying nature of the clinical presentation may cause delay in diagnosis. We report our case and discuss how to diagnose and manage this complication under the sum of cases reported previously in English literature.