Resection of liver metastases from colorectal cancer: does preoperative chemotherapy affect the accuracy of PET in preoperative planning?

Background: Preoperative scanning for hepatic colorectal metastases surgery remains a challenge, especially in the age of preoperative chemotherapy, which has marked biochemical and physical effects on the liver. Integrated fluoro‐deoxyglucose positron emission tomography and computed tomography (FDG‐PET/CT) has applications for detecting extrahepatic disease. The aim of the present study was to investigate FDG‐PET/CT as a preoperative planning tool for detecting liver lesions in patients with and without preoperative chemotherapy. Methods: Patients who had resection of hepatic colorectal metastases between January 2004 and June 2006 were included. Patients were divided into those who received preoperative chemotherapy and those who did not. Malignant hepatic lesions found on each scan were compared with those found on histopathology, intraoperative examination and/or intraoperative ultrasound. Accurate scans (scan lesions corresponded to true lesions), false positives (scan lesions detected at least one non‐lesion) and false negatives (scan lesions missed at least one true lesions) were recorded. Results were also compared on a per lesion basis. Results: A total of 21 patients had preoperative FDG‐PET/CT scans with preoperative chemotherapy and 53 without. Accurate tests were six (29%) for the chemotherapy group versus 28 (53%) for the non‐chemotherapy group (P= 0.06). Notably, there were 11 (52%) underestimations in the chemotherapy group versus 18 (34%) in the non‐chemotherapy group. A total of 1.7 lesions were missed per patient in the chemotherapy group versus 0.7 in those who did not receive chemotherapy. Conclusion: Preoperative assessment with FDG‐PET/CT is not useful for hepatic colorectal metastases, particularly when preoperative chemotherapy is used, with a trend towards underestimation of lesions.     

Versatility of Hemisternotomy for Cardiac Surgery

Abstract   Background: Hemisternotomy has been suggested as a way to reduce morbidity by limiting the invasiveness of surgical interventions but it is often limited to aortic valve disease. This study reviews the experience of one center employing hemisternotomy and compares patient outcomes, both in-hospital and post-discharge, with a matched group of full sternotomy patients. Methods: Propensity scores were used to match all hemisternotomy valve cases (Hemi) to full sternotomy valve cases (Full) (1:2). An in-hospital composite outcome (COMP) was defined as mortality, stroke, deep sternal wound infection, sepsis, or return to operating room (OR) for bleeding or valve dysfunction. Provincial administrative health databases were used to determine freedom from mortality and hospital readmission for cardiac cause. Results: During the study period, 70 patients received hemisternotomy for various cardiac surgical interventions with only 38 patients undergoing isolated aortic valve replacement. Examining valve surgery exclusively, 65 Hemi were matched to 130 Full. In-hospital complications were low in both groups, with 1.0% mortality and a non-significant trend toward COMP in the Full group (Hemi = 4.6%; Full = 8.5%; p = 0.39). Ventilation time was significantly decreased in Hemi (median four vs. six hours; p = 0.002). At two years follow-up, survival was excellent for both (Hemi = 95.0%; Full = 93.6%) and freedom from cardiac morbidity (Hemi = 76.8%, Full = 73.2%) was comparable. Conclusion: Hemisternotomy appears to be a safe, effective, and versatile alternative for many cardiac surgical interventions. With a median follow-up of four years, this study represents the longest cardiac morbidity follow-up for hemisternotomy patients. However, we were unable to conclusively show a morbidity benefit with this incision.     

Outcomes in adults with bicuspid aortic valves

Nikolaos Tzemos, MD; Judith Therrien, MD; James Yip, MD; George Thanassoulis, MD; Sonia Tremblay, MD; Michal T. Jamorski, BSc; Gary D. Webb, MD; Samuel C. Siu, MD, SM

JAMA. 2008;300(11):1317-1325.

Context  Bicuspid aortic valve is the most common congenital cardiac anomaly in the adult population. Cardiac outcomes in a contemporary population of adults with bicuspid aortic valve have not been systematically determined.

Objective  To determine the frequency and predictors of cardiac outcomes in a large consecutive series of adults with bicuspid aortic valve.

Design, Setting, and Participants  Cohort study examining cardiac outcomes in 642 consecutive ambulatory adults (mean [SD] age, 35 [16] years; 68% male) with bicuspid aortic valve presenting to a Canadian congenital cardiac center from 1994 through 2001 and followed up for a mean (SD) period of 9 (5) years. Frequency and predictors of major cardiac events were determined by multivariate analysis. Mortality rate in the study group was compared with age- and sex-matched population estimates.

Main Outcome Measures  Mortality and cause of death were determined. Primary cardiac events were defined as the occurrence of any of the following complications: cardiac death, intervention on the aortic valve or ascending aorta, aortic dissection or aneurysm, or congestive heart failure requiring hospital admission during the follow-up period.

Results  During the follow-up period, there were 28 deaths (mean [SD], 4% [1%]). One or more primary cardiac events occurred in 161 patients (mean [SD], 25% [2%]), which included cardiac death in 17 patients (mean [SD], 3% [1%]), intervention on aortic valve or ascending aorta in 142 patients (mean [SD], 22% [2%]), aortic dissection or aneurysm in 11 patients (mean [SD], 2% [1%]), or congestive heart failure requiring hospital admission in 16 patients (mean [SD], 2% [1%]). Independent predictors of primary cardiac events were age older than 30 years (hazard ratio [HR], 3.01; 95% confidence interval [CI], 2.15-4.19; P<.001), moderate or severe aortic stenosis (HR, 5.67; 95% CI, 4.16-7.80; P<.001), and moderate or severe aortic regurgitation (HR, 2.68; 95% CI, 1.93-3.76; P<.001). The 10-year survival rate of the study group (mean [SD], 96% [1%]) was not significantly different from population estimates (mean [SD], 97% [1%]; P = .71). At last follow-up, 280 patients (mean [SD], 45% [2%]) had dilated aortic sinus and/or ascending aorta.

Conclusions  In this study population of young adults with bicuspid aortic valve, age, severity of aortic stenosis, and severity of aortic regurgitation were independently associated with primary cardiac events. Over the mean follow-up duration of 9 years, survival rates were not lower than for the general population.

     

农村居民主观幸福感与健康的相关性

目的分析农村居民主观幸福感与健康之间的相关性。方法采用昨日重现法和EQ5D量表分别对主观幸福感和健康进行测量,并对二者进行相关分析。结果调查居民中有27%产生过不愉快情绪,平均有47%的时间处于不幸福状态;分别有31.9%和17.9%居民感到疼痛/不舒服、焦虑/沮丧。结论主观幸福感与健康呈正相关关系。     

Extrinsic compression of the left main coronary artery

A 43-year-old female with a remote history of surgical closureof an atrial septal defect with     

Red cell membrane stiffness in iron deficiency

The purpose of this study was to characterize red blood cell (RBC) deformability by iron deficiency. We measured RBC deformability to ektacytometry, a laser diffraction method for determining the elongation of suspended red cells subjected to shear stress. Isotonic deformability of RBC from iron-deficient human subjects was consistently and significantly lower than that of normal controls. In groups of rats with severe and moderate dietary iron deficiency, RBC deformability was also reduced in proportion to the severity of iron deficiency. At any given shear stress value, deformability of resealed RBC ghosts from both iron-deficient humans and rats was lower than that of control ghosts. However, increase of applied shear stress resulted in progressive increase in ghost deformation, indicating that ghost deformability was primarily limited by membrane stiffness rather than by reduced surface area-to-volume ratio. This was consistent with the finding that iron-deficient cells had a normal membrane surface area. In addition, the reduced mean corpuscular hemoglobin concentration (MCHC) and buoyant density of the iron-deficient rat cells indicated that a high hemoglobin concentration was not responsible for impaired whole cell deformability. Biochemical studies of rat RBC showed increased membrane lipid and protein crosslinking and reduced intracellular cation content, findings that are consistent with in vivo peroxidative damage. RBC from iron-deficient rats incubated in vitro with hydrogen peroxide showed increased generation of malonyldialdehyde, an end-product of lipid peroxidation, compared to control RBC. Taken together, these findings suggest that peroxidation could contribute in part to increased membrane stiffness in iron- deficient RBC. This reduced membrane deformability may in turn contribute to impaired red cell survival in iron deficiency.