- Alcohol and substance abuse, depression and suicide attempts after Roux-en-Y gastric bypass surgery. [JOURNAL ARTICLE]
- Br J Surg 2016 Jul 28.
Small studies suggest that subjects who have undergone bariatric surgery are at increased risk of suicide, alcohol and substance use disorders. This population-based cohort study aimed to assess the incidence of treatment for alcohol and substance use disorders, depression and attempted suicide after primary Roux-en-Y gastric bypass (RYGB).All patients who underwent primary RYGB in Sweden between 2001 and 2010 were included. Incidence of hospital admission for alcohol and substance use disorders, depression and suicide attempt was measured, along with the number of drugs prescribed. This cohort was compared with a large age-matched, non-obese reference cohort based on the Swedish population. Inpatient care and prescribed drugs registers were used.Before RYGB surgery, women, but not men, were at higher risk of being diagnosed with alcohol and substance use disorder compared with the reference cohort. After surgery, this was the case for both sexes. The risk of being diagnosed and treated for depression remained raised after surgery. Suicide attempts were significantly increased after RYGB. The adjusted hazard ratio for attempted suicide in the RYGB cohort after surgery compared with the general non-obese population was 2·85 (95 per cent c.i. 2·40 to 3·39).Patients who have undergone RYGB are at an increased risk of being diagnosed with alcohol and substance use, with an increased rate of attempted suicide compared with a non-obese general population cohort.
- Is there a need to assess myocardial viability in patients presenting with heart failure? [JOURNAL ARTICLE]
- Curr Opin Cardiol 2016 Jul 27.
Cardiac MRI is unique amongst the cardiac imaging modalities in its ability to directly image myocardial fibrosis using late gadolinium enhancement techniques. The ability to identify not only the presence of fibrosis but also its pattern of distribution within the myocardium can aid in distinguishing between ischemic and nonischemic causes of left ventricular dysfunction, as well as provide valuable prognostic information for patients with various etiologies of heart failure.Amongst patients with ischemic cardiomyopathy, the Surgical Treatment for Ischemic Heart Failure (STICH) trial was attempted to assess the value of coronary artery bypass surgery. Although the early results were disappointing as to the overall utility of surgical revascularization, the recently published 10-year follow-up now demonstrates improved survival amongst patients undergoing surgical revascularization when compared with medical therapy alone. Although a substudy of STICH failed to demonstrate utility of preprocedural viability assessment with dobutamine echocardiography or single-photon-emission computed tomography, other studies support the identification of myocardial fibrosis as carrying important prognostic information. The ongoing development of new techniques, particularly T1 mapping of extracellular volume fraction, holds promise for the future as early studies suggest complementary prognostic value and perhaps the ability to avoid contrast administration.Cardiac MRI use for viability assessment demonstrates important utility amongst patients with heart failure, regardless of its cause.
- Translesion synthesis of O4-alkylthymidine lesions in human cells. [JOURNAL ARTICLE]
- Nucleic Acids Res 2016 Jul 27.
Environmental exposure, endogenous metabolism and cancer chemotherapy can give rise to alkylation of DNA, and the resulting alkylated thymidine (alkyldT) lesions were found to be poorly repaired and persistent in mammalian tissues. Unrepaired DNA lesions may compromise genomic integrity by inhibiting DNA replication and inducing mutations in these processes. In this study, we explored how eight O(4)-alkyldT lesions, with the alkyl group being a Me, Et, nPr, iPr, nBu, iBu, (R)-sBu and (S)-sBu, are recognized by DNA replication machinery in HEK293T human embryonic kidney cells. We found that the O(4)-alkyldT lesions are moderately blocking to DNA replication, with the bypass efficiencies ranging from 20 to 33% in HEK293T cells, and these lesions induced substantial frequencies T→C transition mutation. We also conducted the replication experiments in the isogenic cells where individual translesion synthesis (TLS) DNA polymerases were depleted by the CRISPR/Cas9 genome editing method. Our results showed that deficiency in Pol η or Pol ζ, but not Pol κ or Pol ι, led to pronounced drops in bypass efficiencies for all the O(4)-alkyldT lesions except O(4)-MedT. In addition, depletion of Pol ζ resulted in significant decreases in T→C mutation frequencies for all the O(4)-alkyldT lesions except O(4)-MedT and O(4)-nBudT. Thus, our study provided important new knowledge about the cytotoxic and mutagenic properties of the O(4)-alkyldT lesions and defined the roles of TLS polymerases in bypassing these lesions in human cells.
- Structured dietary intervention to facilitate weight loss after bariatric surgery: A randomized, controlled pilot study. [JOURNAL ARTICLE]
- Obesity (Silver Spring) 2016 Jul 28.
To evaluate the potential utility of a structured dietary intervention to assist bariatric surgery patients with weight management.Participants who underwent Roux-en-Y gastric bypass surgery 1 year previously were randomly assigned to a structured dietary intervention incorporating portion-controlled foods (intervention, n = 20) or a comparison group (control, n = 20). Both groups received instruction in behavioral weight loss (one 60-min session) followed by four monthly coaching telephone calls. Assessments were conducted at baseline, 4 months (post-intervention), and 6 months.Participants were 85% female and 80% White. Average age was 46.9 (11.1) years, and body mass index was 31.3 (5.4) kg/m(2) at enrollment. Percent weight change from enrollment was significantly greater for intervention compared with control participants at 4 months [-4.56% vs. -0.13%, t(30) = -3.29, P = 0.003] and 6 months [-4.07% vs. -0.14%, t(31) = -2.03, P = 0.05]. Change in average daily calorie intake was greater among intervention compared with control [-108 vs. 116, t(30) = -2.01, P = 0.05] at 4 months only.A structured dietary intervention increased weight loss and reduced calorie intake when initiated 1 year following Roux-en-Y gastric bypass. This approach holds promise for optimizing postsurgery lifestyle change.
- The Phase Angle of the Bioelectrical Impedance Analysis as Predictor of Post-Bariatric Weight Loss Outcome. [JOURNAL ARTICLE]
- Obes Surg 2016 Jul 27.
Bariatric surgery is proven to be the most effective therapy for obesity. However, the targeted weight reduction is not always achieved. Reliable predictors for postoperative success are rare. Also, most available predictors, such as gender and socioeconomic status, cannot be influenced. The aim of the study was to assess the reliability of the phase angle (PhA) as a predictor of weight reduction and body composition after bariatric surgery.One hundred seventy-three patients (127 with Roux-en-Y gastric bypass and 46 with sleeve gastrectomy), treated between January 2004 and December 2012, were included into this prospective trial. Bioelectrical impedance analysis (BIA) was performed before and five times within the first year after the operation. Correlation between excess weight loss (EWL) was calculated using Pearson's correlation coefficient and a receiver operating characteristic (ROC) curve.The average weight loss was significant with a total weight loss of 30.1 %, while the PhA did not show any significant decrease during the first 12 months after surgery. The correlation between the preoperative PhA and the postoperative EWL was significant after 6 weeks and after 6, 9, and 12 months. The ROC curve has an area of 0.7. The best point of the curve is a PhA of 3.9° with a sensitivity of 81 % and a specificity of 54 %.PhA may be a useful predictor of EWL after bariatric surgery, and a PhA of 3.9° was calculated as the most suitable cut-off for a successful operation.
- The IGF-Axis and Diabetic Retinopathy Before and After Gastric Bypass Surgery. [JOURNAL ARTICLE]
- Obes Surg 2016 Jul 27.
Laparoscopic gastric bypass (LGB) abruptly causes remission of type 2 diabetes (T2D). Such dramatic metabolic changes have previously been found to cause worsening of diabetic retinopathy (DR) and circulating insulin-like growth factor I (IGF-I) has been suggested as a causal mediator. We aimed to evaluate baseline imbalances in the circulating IGF-system and changes after LGB in patients with T2D.Prospective ocular examinations and measurement of the IGF-axis before and 3 and 12 months after LGB. IGF-bioactivity was measured by cell-based IGF-I receptor (IGF-IR) kinase activation assay (bioactive IGF). Total IGF-I, IGF-II and IGF binding protein (IGFBP) 1 and 3 were determined by immunoassays.At baseline, 18 of 36 patients presented with DR. These patients had higher levels of bioactive IGF (p = 0.03) than patients without DR and this association was strengthened in multivariate analysis (p = 0.006). Three patients had worsening of DR, unrelated to other markers. In univariate analysis, bioactive IGF increased at 3 months (p = 0.05) but this change became insignificant in multivariate analysis (p = 0.11). IGFBP-1 increased whereas IGFBP-3 and total IGF-II decreased at the two postoperative visits (p ≤ 0.001). Total IGF-I showed no significant changes. HbA1c, glucose, HOMA-IR and lipids improved after surgery. Two patients did not complete the 12-month visit.In obese T2D patients, bioactive IGF is a potential biomarker for DR and levels tended to increase 3 months after bariatric surgery. IGFBP-1 increased while IGFBP-3 and total IGF-II decreased postoperatively, but these changes were unassociated with the development of DR. Markers of the metabolic syndrome improved.
- Can Combined Bypass Surgery at Middle Cerebral Artery Territory Save Anterior Cerebral Artery Territory in Adult Moyamoya Disease? [JOURNAL ARTICLE]
- Neurosurgery 2016 Jul 25.
Patients with moyamoya disease are frequently encountered with improved symptoms related to anterior cerebral artery territory (ACAt) and middle cerebral artery territory (MCAt) after bypass surgery at MCAt.To evaluate hemodynamic changes in MCAt and ACAt after bypass surgery in adult moyamoya disease.Combined bypass surgery was performed on 140 hemispheres in 126 patients with MCAt symptoms. Among them, 87 hemispheres (62.1%) accompanied preoperative ACAt symptoms. Clinical, hemodynamic, and angiographic states were evaluated preoperatively and approximately 6 months after surgery.Preoperative symptoms resolved in 127 MCAt (90.7%) and 82 ACAt (94.3%). Hemodynamic analysis of total patients showed a significant improvement in MCAt basal perfusion and reservoir capacity (P < .001 and P = .002, respectively) and ACAt basal perfusion (P = .001). In a subgroup analysis, 82 hemispheres that completely recovered from preoperative ACAt symptoms showed a significant improvement in MCAt basal perfusion and reservoir capacity (P < .001 and P = .05, respectively) and ACAt basal perfusion (P = .04). Meanwhile, 53 hemispheres that had never experienced ACAt symptoms significantly improved MCAt basal perfusion and reservoir capacity (P < .001 and P = .05, respectively); however, no ACAt changes were observed. A qualitative angiographic analysis demonstrated a higher trend of leptomeningeal formation from MCAt to ACAt in the former subgroup (P = .05). During follow-up, no ACAt infarctions were observed.Combined bypass surgery at MCAt resulted in hemodynamic improvements in ACAt and MCAt, especially in patients with preoperative ACAt symptoms.ACAt, anterior cerebral artery territoryCA, craniotomy areaCBF, cerebral blood flowCVRI, cerebrovascular reserve indexMCAt, middle cerebral artery territoryMMD, moyamoya diseaseMMV, pachymeningeal collaterals from ethmoidal moyamoya vesselsPCAt, posterior cerebral artery territoryRA, revascularization areaSPECT, single-photon emission computed tomography.
- The clinical utility of new cardiac imaging modalities in Australasian clinical practice. [Journal Article]
- Med J Aust 2016 Aug 1; 205(3):134-9.
Cardiac imaging is a rapidly evolving field, with improvements in the diagnostic capabilities of non-invasive cardiac assessment. We review the two main emerging technologies in cardiac imaging: computed tomography coronary angiography (CTCA) to evaluate chest symptoms and to exclude coronary artery disease; and cardiovascular magnetic resonance (CMR) for evaluating cardiac morphology, function and presence of scar. CTCA is an excellent "rule out" test, with a negative predictive value approaching 100%. Radiation exposure is no longer a concern for CTCA, with doses routinely < 5 mSv, and as low as < 1 mSv in selected patients. CTCA is useful for excluding coronary artery disease, investigating the anatomy of coronary anomalies or fistulae, and for the patency of coronary bypass grafts. CMR is the reference test for the accurate quantitation of left ventricular and right ventricular size and function. CMR has no ionising radiation, making it particularly suitable for patients with heart failure or congenital heart disease who require longitudinal follow-up. Evaluation of cardiomyopathies (hypertrophic, ischaemic, infiltrative, myocarditis, iron overload or idiopathic) is a unique strength of CMR. Stress perfusion CMR has a strong evidence base and improved spatial and temporal resolution compared with nuclear single-photon emission computed tomography.
- Distal coronary perforation in patients with prior coronary artery bypass graft surgery: The importance of early treatment. [REVIEW, JOURNAL ARTICLE]
- Cardiovasc Revasc Med 2016 Jun 17.
In patients with prior coronary artery bypass graft (CABG) surgery, distal coronary perforations are commonly considered to be at low risk for causing cardiac tamponade due to a potential protective role of pericardial adhesions, which obliterate the pericardial space. Loculated effusions can however form in such patients, compressing various cardiac structures and causing hemodynamic compromise. We present two cases of distal coronary perforation in prior CABG patients undergoing chronic total occlusion percutaneous coronary intervention. In the first case a distal coronary perforation was initially observed, resulting in a loculated pericardial effusion that caused ST-segment elevation and death, despite successful sealing of the perforation. In the second case a similar perforation was immediately sealed with a covered stent, followed by uneventful patient recovery. A literature review of coronary perforation leading to hemodynamic compromise in patients with prior CABG surgery revealed high mortality (22%), suggesting that prompt sealing of the perforation is critical in these patients.
- Existence of renal dysfunction in diabetics undergoing coronary artery bypass. [JOURNAL ARTICLE]
- Asian Cardiovasc Thorac Ann 2016 Jul 27.
The effect of diabetes mellitus on morbidity and mortality in patients undergoing coronary artery bypass grafting has remained uncertain, and conflicting conclusions have been reported in clinical trials. Evidence suggests that coronary artery bypass in patients with diabetes mellitus carries a higher risk of stroke, renal failure, perioperative complications, and sternal wound infection. This study evaluated the frequency of acute renal dysfunction after coronary artery bypass in diabetic patients, and the associated risk factors.This cross-sectional observational study included 135 patients with diabetes (111 males and 24 females with a mean age 51 years and a body mass index of 27.44 kg m(-2)), who underwent elective coronary artery bypass from March 2015 to October 2015. Data were collected prospectively in 2 tertiary care centers. Renal dysfunction was assessed by serum creatinine levels preoperatively and at 24 and 48 h postoperatively.Fifteen percent of patients were found to have postoperative renal dysfunction. Univariate analysis revealed that patients with increased serum creatinine preoperatively were at greater risk of developing renal dysfunction after coronary artery bypass (p = 0.00). On multivariable binary logistic regression analysis, preoperative serum creatinine level was the only independent predictor of postoperative renal dysfunction; age, body mass index, dyslipidemia, hypertension, cardiopulmonary bypass time, and aortic crossclamp time showed no significant association.Diabetic patients with increased serum creatinine preoperatively are at greater risk of kidney damage postoperatively; therefore, these patients should be monitored and treated critically in the perioperative period.