Surgical treatment of lone atrial fibrillation in an awake patient

Surgical treatment of atrial fibrillation recently gained new popularity since the introduction of different energy sources and the development of minimally invasive techniques as an alternative to the original "cut-and-sew" technique. However, closed-chest ablation procedures are not feasible in presence of pericardial or pleural adhesions. To our knowledge, this is the first report of surgical treatment of atrial fibrillation in a conscious patient by means of a high epidural anesthesia. Since evidence of fibrothorax was found, a conscious patient suffering from lone atrial fibrillation underwent a beating-heart pulmonary veins isolation with a microwave device through a standard sternotomic approach. At 6 months follow-up, the patient is in stable sinus rhythm, without any palpitation nor electrocardiographic evidence (Holter monitoring) of recurrent atrial fibrillation.     

A critical assessment of the prognostic value of clear cell,papillary and chromophobe histological subtypes in renal cell carcinoma: a population‐based study

OBJECTIVE

To assess the magnitude of the effect of histological subtype (HS, the three most common being clear cell, papillary and chromophobe) on cause‐specific mortality (CSM) from renal cell carcinoma (RCC).

PATIENTS AND METHODS

Univariable and multivariable Cox regression models included data from 11 618 patients treated with nephrectomy between 1988 and 2004 in nine Surveillance Epidemiology and End Results registries. We tested whether HS represents an independent predictor of CSM, and whether HS adds to the ability of other variables to predict CSM. The covariates comprised age, year of surgery, T stage, nodal status, M stage and Fuhrman grade.

RESULTS

In a multivariable model predicting CSM, HS was an independent predictor (P = 0.03), but failed to improve the accuracy of the model (+0.1% gain when HS was included in the model).

CONCLUSION

Although we confirmed that HS is an independent predictor for CSM, there was no gain in accuracy when HS was added to standard predictors of CSM. From a practical perspective, this implies that patients with clear cell, papillary and chromophobe HS share similar natural histories after nephrectomy, provided that other cancer characteristics are accounted for. From a statistical perspective, in multivariable models of CSM, the clear cell, papillary and chromophobe HS might be included as a single entity.     

Radiation-induced intracranial meningiomas: review of six operated cases

It is well known that radiation can induce meningiomas. These tumors usually arise in patients with a history of low-dose radiation to the scalp for treatment of tinea capitis or high-dose radiation for a previous brain tumor. Radiation-associated meningiomas (RAMs) morphologically resemble their spontaneously arising counterparts. However, RAMs frequently present a more malignant phenotype and, as such, are diagnosed as atypical or aggressive meningiomas and occur predominantly in younger patients. This paper describes six cases of radiation-associated intracranial meningiomas in patients previously treated with low-dose radiation to the scalp for tinea capitis.     

F-18-fluorodeoxyglucose positron emission tomography in differentiating malignant from benign pancreatic cysts: A prospective study

The differential diagnosis between benign and malignant pancreatic cystic lesions may be very difficult. We recently found that F-18-.uorodeoxyglucose positron emission tomography (18-FDG PET) was useful for the preoperative work-up of pancreatic cystic lesions. This study was undertaken to confirm these results. From February 2000 to July 2003, 50 patients with a pancreatic cystic lesion were prospectively investigated with 18-FDG PET in addition to helical computed tomography (CT) and, in some instances, magnetic resonance imaging (MRI). The validation of diagnosis was based on pathologic findings after surgery (n = 31), percutaneous biopsy (n = 4), and according to follow-up in 15 patients. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). The accuracy of FDG PET and CT was determined for preoperative diagnosis of malignant cystic lesions. Seventeen patients had malignant cystic lesions. Sixteen (94%) showed increased 18-FDG uptake (SUV >2.5), including two patients with carcinoma in situ. Eleven patients (65%) were correctly identified as having malignancy by CT. Thirty-three patients had benign tumors: two patients showed increased 18-FDG uptake, and four patients showed CT findings of malignancy. Sensitivity, specificity, positive and negative predictive value, and accuracy of 18-FDG PET and CT in detecting malignant tumors were 94%, 94%, 89%, 97%, and 94% and 65%, 88%, 73%, 83%, and 80%, respectively. 18-FDG PET is accurate in identifying malignant pancreatic cystic lesions and should be used in combination with CT in the preoperative evaluation of patients with pancreatic cystic lesions. A negative result with 18-FDG PET may avoid unnecessary operation in asymptomatic or high-risk patients. Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004 (oral presentation). This study was supported by the Ministero Università e Ricerca Scientifica (Cofin 2001068593-001), Rome, Italy.     

Preservation of Muscular and Elastic Artery Distensibility After an Intercontinental Cryoconserved Exchange: Theoretical Advances in Arterial Homograft Generation and Utilization

While the situation of tissue donation and transplantation differs between Latin American and European countries, a common problem is tissue deficiency. Hence, at present, there is a pressing need to generate alternatives so as to increase the possibilities of obtaining the requested materials. Consequently, it would be of significant interest to establish an intercontinental network for tissue exchange, to improve international cooperation, and to help patients that need tissue transplantation, and to evaluate the feasibility of using an intercontinental network for the exchange of cryopreserved arteries (cryografts), preserving the arterial distensibility and ensuring a reduced native artery–cryograft biomechanical mismatch. Distensibility was studied in ovine arteries divided into three groups: intact (in vivo tests, conscious animals), fresh control (in vitro tests immediately after the artery excision, Uruguay), and cryografts (in vitro tests of cryopreserved-transported-defrosted arteries, Spain). Histological studies were performed so as to analyze changes in the endothelial layer and elastic components. The comparison between fresh control and cryografts showed that neither the cryopreservation nor the exchange network impaired the distensibility, despite the expected histological changes found in the cryografts. The comparison between intact and cryografts showed that the cryografts would be capable of ensuring a reduced biomechanical mismatch. The cryopreservation and the intercontinental network designed for artery exchange preserved the arterial distensibility. It could be possible to transfer cryografts between Latin America and Europe to be used in cardiovascular surgeries and/or for tissue banking reprocessing, with basic biomechanical properties similar to those of the fresh and/or native arteries.     

Obesity does not increase the risk of lymph node metastases in patients with clinically localized prostate cancer undergoing radical prostatectomy and extended pelvic lymph node dissection

Objectives: Several studies have shown that obesity is associated with more aggressive prostate cancer (PCa) variants. We hypothesized that obesity, quantified as body mass index (BMI), is associated with a higher risk of lymph node invasion (LNI) in patients undergoing extended pelvic lymph node dissection (ePLND). Methods: Clinical and pathological data were available for 994 consecutive men with PCa treated with radical prostatectomy (RP) and ePLND at a single European tertiary academic centre. Univariable and multivariable logistic regression analyses addressed the rate of LNI. Covariates consisted of pre‐treatment prostate specific antigen (PSA), biopsy Gleason sum, clinical stage history of diabetes mellitus as well as BMI coded as either continuous or categorized (<25, 25.0–29.9, 30 kg/m² or more) variable. Predictive accuracy was assessed with area under curve estimates. Results: Overall LNI was diagnosed in 105 patients (10.6%). Mean number of removed lymph nodes was 18.3 (range 7–60). Of all 994 patients, 372 (37.4%) were normal weight, 518 (52.1%) overweight, and 104 (10.5%) were clinically obese. Prevalence of LNI did not significantly differ across different BMI categories (<25, 25.0–29.9 and 30 kg/m² or more; 9.9, 10.6 and 12.5%, respectively; P = 0.75). In logistic regression models, neither continuously coded nor categorized BMI was a significant predictor of LNI at univariable or multivariable analyses (all P‐values ≥0.1). Moreover, inclusion of BMI with PSA, clinical stage, biopsy Gleason sum and presence of DM did not increase the ability of these variables to predict LNI (82.2% without BMI vs 82.5% and 82.9% with BMI coded as continuous and categorized variable, respectively; all P ≥ 0.4). Conclusions: In men undergoing RP and ePLND, increased BMI was not associated with increased risk of lymph node metastases. Therefore, routinely considering patient BMI in risk stratification schemes or prognostic LNI models may not be warranted.     

The probability of Gleason score upgrading between biopsy and radical prostatectomy can be accurately predicted

The objective of this study was to test the external validity of a previously developed nomogram for the prediction of Gleason score upgrading (GSU) between biopsy and radical prostatectomy (RP). The study population consisted of 973 assessable patients treated with RP at a tertiary care institution. The accuracy of the nomogram was quantified with the receiver operating characteristics curve-derived area under the curve. The performance characteristics (predicted vs observed rate of GSU) were tested within a calibration plot. Overall, GSU was recorded in 39.8% ( n  = 387) of patients at RP. Of patients with GSU, 70 (18.1%), 23 (5.9%) and 32 (8.3%), respectively, had extracapsular extension, seminal vesicle invasion and lymph node invasion. The accuracy of the nomogram was 74.9% (confidence interval 72.1–77.6%). The model tended to underestimate the observed rate of GSU and the discordance between the predicted and observed rate of GSU ranged from −7 to +10%. The current tool represents the most accurate method of predicting GSU between biopsy and RP. Nonetheless it is not perfect and its performance characteristics should be known prior to its use in clinical decision-making.     

Noncardiac surgical procedures in patient supported with long-term implantable left ventricular assist device

Background

Left ventricular assist devices (LVADs) are increasingly used as bridges to transplantation or as destination therapy. As sicker and older patients are more frequently considered for mechanical support, general surgical problems are expected to increase in these patients.

Methods

Anesthesia records and clinical charts were reviewed for 11 recipients of LVADs undergoing 12 general surgical procedures between January 1988 and March 2007.

Results

Eight patients underwent major surgical procedures: 1 intracranial hematoma drainage, 1 right hemicolectomy with ileocolostomy, 1 splenectomy, 1 surgical repair of an iliac-femoral artery pseudoaneurysm, 2 cholecystectomies, 1 pyelolithotomy, and 1 coil embolization of a femoral side-branch disruption. Four patients underwent minor surgical procedures. The mean duration of LVAD support before surgery was 58.7 ± 45.6 days. All patients survived the procedures.

Conclusion

Noncardiac surgery in LVAD recipients is feasible, without significant morbidity or mortality. Intraoperative coagulation management has a key role in safely performing these procedures.     

Heme oxygenase-1 attenuates ischemia/reperfusion-induced apoptosis and improves survival in rat renal allografts

BACKGROUND: Kidneys can be preserved only for a limited time without jeopardizing graft function and survival. Induction of heat shock proteins (HSPs) can protect against ischemia/reperfusion (I/R) injury. Therefore, we investigated whether the induction of the HSP, heme oxygenase-1 (HO-1), improves outcome following isotransplantation after an extended period of cold storage. METHODS: Rats were subjected to heat preconditioning (HP; 42 degrees C for 20 minutes). Kidneys harvested after 24 hours, were preserved in cold University of Wisconsin (UW) solution at 4 degrees C for 45 hours and transplanted into bilateral nephrectomized rats. Cobalt protoporphyrin (CoPP) was administered in another group of animals in order to induce HO-1 pharmacologically, while other groups of animals received the HO-1 inhibitor, tin protophorphyrine (SnPP), following HP or CoPP. RESULTS: Cold ischemia caused a complete attenuation of graft function within 3 days following transplantation and subsequent death of all animals, whereas HP protected graft function and five of nine rats survived for 3 weeks. HP inhibited the induction of osteopontin and induced the expression of HO-1, HSP 70 and 90, and the antiapoptotic factor Bcl-XL. Grafts exposed to HP were protected against structural I/R injuries as revealed by histologic assessment using a semiquantitative score. Furthermore, induction of apoptosis was attenuated and activation of caspase-3 was inhibited. Comparable results were observed after administration of CoPP, whereas SnPP inhibited the effects of HP and CoPP. CONCLUSION: HP or administration of CoPP induced both HO-1, preserved kidney graft function, and prevented postreperfusion apoptosis after cold preservation.