Vivek Srivastava

Efficacy of three different ablative procedures to treat atrial fibrillation in patients with valvular heart disease: a randomised trial.

OBJECTIVES Various modifications have been proposed to the original Coxs Maze procedure due to concerns about the long bypass and cross clamp times. The efficacy of these procedures has been studied and reported. We conducted a randomised prospective study to compare three procedures, differing in extent, of ablation in patients in atrial fibrillation who were undergoing surgery for rheumatic valvular heart disease. These procedures utilised radiofrequency in the bipolar mode. The extent of ablation was (1) biatrial (replication of the Cox Maze) (2) left atrial portion of the Cox Maze and (3) pulmonary vein isolation along with a control group (the No Maze group). Conversion rate to sinus rhythm was studied over a mid-term follow-up period. METHODS A total of 160 patients were studied with 40 patients in each group. Antiarrhythmic drugs were not used in the three months preceding surgery and for seven days postoperatively. The patients underwent surgery for their valve disease along with the ablative procedure as per randomisation using radiofrequency microbipolar coagulation and cryoablation. They were followed up and were evaluated for symptomatic improvement, rhythm with ECG documentation and 2D echocardiography. RESULTS Follow-up was available for 133 patients. Mid-term results showed that sinus rhythm was restored in 62.5% patients of Biatrial Maze group and 57.5% in the Left Atrial Maze. In the Pulmonary Vein Isolation Maze group, 67.5% patients converted to NSR whereas in the No Maze group only 20% patients were in sinus rhythm (p value for all the groups was 0.001 when compared to the No Maze group). The incidence of other arrhythmias was not significant and there were no other major complications. All the patients in sinus rhythm at follow-up were in NYHA functional class I-II and showed good effort tolerance. CONCLUSIONS Results achieved with the three ablative procedures are comparable. Therefore lesser procedures viz. Left Atrial Maze and the Pulmonary Vein Isolation Maze procedures must be studied further with the additional use of antiarrhythmic drugs.

Residual strength of aluminum-lithium alloy center surface crack tension specimens at cryogenic temperatures

Abstract A three parameter fracture criterion which correlates the stress and the stress intensity factor at failure, is followed for the residual or fracture strength estimations of cracked configurations made of aluminum–lithium (Al–Li) alloys. The three fracture parameters are determined from the fracture data of Al–Li alloy center surface crack tension (SCT) specimens at cryogenic temperatures. It is found that the estimated fracture strength values compare well with the test results.

Notched tensile strength for long- and short-fiber reinforced polyamide

The point stress criterion and the average stress criterion are applied for evaluating the notched tensile strength of injection-moulded plates with machined and moulded-in notches. Use is made of a characteristic length which is found to be geometry and material dependent.

Tensile fracture strength of boron/aluminum laminates with holes and slits

Abstract This paper improves the stress fracture criteria proposed by Whitney–Nuismer known as the point stress criterion (PSC) and the average stress criterion (ASC), to predict the strength of composite laminates containing holes and slits. A simple relation is used for the characteristic length to improve the accuracy while evaluating the notched strength of laminates. The applicability of the proposed approach is examined by considering the notched strength data on carbon/epoxy and boron/aluminum laminates. The analytical results obtained in the present study correlate well with the test results of different notched configurations. This study confirms that the present modification in the stress fracture criteria can be used for notched strength evaluation of composite laminates.

Color Doppler ultrasonography for treatment response prediction and evaluation in breast cancer

Primary systemic therapy is a well-established modality of treatment in locally advanced breast cancer. Assessment of tumor response to chemotherapy not only helps in assessing the efficacy of the regimen used but also predicts the overall outcome of the patient. The tumor vascularity is a surrogate marker of tumor burden and this can be readily assessed by color Doppler ultrasound using various indices (resistivity index, pulsatility index and maximum flow velocity). The pre- and post-chemotherapy indices can be compared with in order assess the response to chemotherapy. Among various imaging modalities, MRI and PET have the highest sensitivity in detecting the tumor response, but they are not cost effective. Color Doppler ultrasound is a promising alternative for tumor response assessment owing to its availability, reproducibility and cost-effectiveness.

Massive gangrene of the stomach due to primary antiphospholipid syndrome: Report of two cases

Antiphospholipid syndrome (APS) is a systemic autoimmune disease, which may be primary or secondary to other autoimmune diseases. It produces thrombosis of arteries and veins of any caliber, and no organ is immune to its insult. This report describes two cases of massive gastric gangrene due to primary APS, which presented in a span of 2 years. In the first case a multiparous, 40-year-old woman presented with acute abdominal pain, hematemesis, and progressive abdominal distension, and was in azotemia and shock. A laparotomy revealed gangrene of the stomach without any other organ involvement. She was managed with a total gastrectomy and esophagojejunal anastomosis. Postoperative serology revealed a persistent elevation of anticardiolipin antibody with no other apparent predisposing cause. The histopathological examination of the specimen revealed characteristic extensive intramural vascular thrombosis without inflammatory changes in the vessel wall, confirming antiphospholipid syndrome. The second patient was a primiparous, 26-year-old woman who had severe abdominal pain in the first trimester followed by shock. An exploratory laparotomy revealed massive gangrene of the stomach with complete loss of the posterior wall and hemoperitoneum. She also underwent a total gastrectomy with esophagogastric anastomosis and was later managed in the intensive care unit, where she succumbed within 8 days. Her serology showed a highly elevated anticardiolipin antibody titer, and histopathological examination of the stomach revealed characteristic intramural vascular thrombosis without inflammatory cellular infiltrate in the vessel wall. Patients undergoing a total gastrectomy following acute gastric necrosis have very high mortality (50%–80%). Its association with APS is rare and it has not been previously reported. The combination is a formidable challenge to the physician and a dangerous disease for the patient. The rarity of the condition and its grave prognosis is highlighted.

Study of Anxiety and Depression among Breast Cancer Patients from North India

Background: The prevalence of psychological distress among breast cancer patients is high, and they are at higher risk of developing severe anxiety, depression and potential mood disorders. In the present study, we conducted prospective study to determine the socioeconomic factors associated with anxiety and depression among breast cancer patients and to access the changes of psychological distress after the completion of treatment at 1 year of follow-up. Methods: This study was conducted among breast cancer patients enrolled in the Department of General Surgery, Sir Sunderlal Hospital, Banaras Hindu University, Varanasi, India. A total of 200 patients who were diagnosed from January, 2013 to December, 2014 were interviewed using the questionnaires of Hospital Anxiety and Depression (HADS). The HADS was administered at two time points: at time of diagnosis and 12 months after completion of treatment. The associated factors investigated concerned socio-demographics, socio-economic background and the cancer stage. Results: Prevalence of anxiety and depression among the breast cancer patients was 37.0% (n=74) and 28.0% (n=56) respectively. We found strong association of anxiety with age group (p=0.014), educational level (p=0.034), monthly income (p=0.001) and financial support (p=0.041). However, marital status (p=0.014), monthly income (p=0.017), accompanying person (p=0.005) and financial support (p=0.002) were significantly associated with depression. Binary logistic regression analysis shows age younger than 50 years old, those earned less income, illiterate or low level of education, being single and receiving less financial support are more likely to have anxiety. For depression, those earned less income, being single and receiving lesless financial support are more likely to have depression. At the 12 month follow-up, 184 breast cancer patients were re-interviewed. We found significant improvement (P<0.001) after 12 month follow-up in both anxiety and depression level (mean anxiety level improved from 11.14 ? 4.23 to 8.64 ? 3.63 and mean depression score improved from 6.87 ? 3.11 to 5.13 ? 4.51. Conclusion: Study clearly shows that younger age group, low monthly income, having less financial support, low education level and being single were associated with anxiety and depression. For managing breast cancer patients, more care or support should be given to this type of patients as they are at high risk of anxiety and depression.

recent advances in the management of carcinoma of the rectum

In the last two decades rectal cancer has changed from a surgically managed disease into a multidisciplinary treatment model resulting in considerable improvements in the survival and outcome. This has been made possible by better understanding of the tumor biology and oncogenesis, advances in diagnostic and staging investigations, and the changing concepts in surgical excision; from the days of abdominoperineal resection to the concept of “zone of upward spread” and low anterior resection to the era of total mesorectal excision and transanal excision. Efforts are on the way to risk stratification and identification of predictors of nonoperative management. Impressive advances in the adjuvant therapies have seen a sea change in the form of postoperative radiotherapy to preoperative radiotherapy to preoperative chemoradiotherapy and postoperative adjuvant chemotherapy. This multidisciplinary approach is the key to impressive local control rates, decreased metastatic rates, overall survival, and enhancement in quality of life. Newer ideas in the understanding of genetic differences in rectal cancers have stemmed from the observation that these cancers differ in their response to the adjuvant treatment. The present day research has focused these areas of biologic differences in cancers and aims to target the specific loci in malignant cells with monoclonal antibodies directed against various growth factors, key enzyme inhibition, and genetic manipulation. The future research lies in the study of gene expression, micro-array techniques, molecular markers, and better understanding of the predictors of tumor response to therapy.

Residual strength of composite laminates with a centre crack under tension

An empirical relationship between the failure stress and stress intensity factor at failure is examined for the estimation of residual strength of various types of laminates with different layup sequence and having centre cracks. The estimated fracture strengths for these laminates under tension are compared with existing experimental results. They are found to be in reasonably good agreement with each other.

Duodenojejunal junction web masquerading as Wilkie’s syndrome: Report of a case

Wilkie’s syndrome (superior mesenteric artery syndrome) is a rare cause of obstruction to the third part of duodenum due to compression between the superior mesenteric artery and the abdominal aorta. Pathologies like malignant growth in the mesenteric root, the presence of a lymph nodal mass compressing the terminal duodenum, dissecting aortic aneurysm, and intestinal malrotation may mimic the condition, but are not true etiologies of the syndrome. A duodenojejunal web causing narrowing of the duodenojejunal junction and mimicking Wilkie’s syndrome has not been described before in the literature. We herein report a case of gastroduodenal obstruction due to a web in the duodenojejunal junction in a young female patient, which closely mimicked Wilkie’s syndrome but was finally diagnosed postoperatively. We highlight the first case of its kind in an adult and discuss the challenges in both the diagnosis and management.