Routine CT angiography to detect severe coronary artery disease prior to transcatheter aortic valve replacement.

Patients undergoing TAVR undergo routine CT angiography (CTA) to assess aorto-iliac pathology and annular dimensions. While coronary CTA may exclude severe CAD in younger patients, its efficacy in defining CAD severity prior to TAVR may be limited. We retrospectively studied 50 consecutive patients undergoing both invasive coronary angiography (ICA) and routine pre-TAVR CTA. Severe CAD was defined as ≥50% stenosis by quantitative coronary angiography and compared to a blinded CTA visual estimation of ≥50% stenosis. The analysis was confined to four segments: left main and three proximal to mid major coronaries to maximize myocardial territory at risk. Coronary assessment was performed using standard reconstructed ECG phases from pre-TAVR chest CTA on a Philips 256 iCT scanner. Nearly ¾ of patients were ≥75 years old, 57% were female, half were diabetic and 45% had prior PCI. By ICA, 49% had significant coronary calcification. The incidence of severe proximal to mid vessel CAD by ICA was 39%. Similarly, a third of patients required PCI prior to TAVR. CTA was unable to exclude severe proximal to mid vessel CAD in 88% of patients in all four segments: non-diagnostic CTA readings were mainly due to calcification (60%) or motion artifact (28%). Non-diagnostic coronary CTA readings ranged from 25 to 72% according to segment analyzed: only the left main segment had diagnostic quality CTA in the majority of patients (p < 0.01). PCI is performed frequently prior to TAVR based upon invasive coronary angiographic assessment. Routine chest CTA algorithms do not provide adequate diagnostic information to exclude severe CAD, primarily due to severe coronary calcification in the TAVR population.

Immunohistochemical evaluation of p53, FHIT, and IGF2 gene expression in esophageal cancer.

The aim of the study was to evaluate the expression of tumor suppressor genes p53, fragile histidine triad gene (FHIT), and an oncogene insulin-like growth factor 2 (IGF2) as prognostic markers in the etiology of esophageal cancer. Immunohistochemistry (IHC) was performed in 39 archival tissue samples of different esophageal pathologies for the three genes. Abnormal p53 expression was maximum in all the cases of squamous cell carcinoma, while IGF2 expression was enhanced in squamous cell carcinoma (81%), adenocarcinoma (100%), and dysplasia of squamous epithelium (75%) samples when compared with normals (50%). To our surprise, 75% of normal tissues did not show FHIT expression, which was also not seen in 40% of dysplasias of squamous epithelium, 33.3% of adenocarcinoma, and 41% of squamous cell carcinoma. To the best of our knowledge, this is the first study evaluating IGF2 by IHC, as well as, correlating it with the expression of the two tumor suppressor genes, p53 and FHIT, in esophageal tissue. p53 expression was threefold higher than normal in dysplasias of squamous epithelium and adenocarcinoma, while it was eightfold higher in squamous cell carcinoma. IGF2 expression was low in normal and dysplasia tissue but was increased 1.97-fold in both types of malignancy. FHIT and p53 expression were well correlated in squamous cell carcinoma, supporting the observation that FHIT regulates and stabilizes p53. Altered/lowered FHIT levels may be a result of exposure to various exogenous agents; however, this could not be assessed in the present study as it was carried out on archival samples. A larger prospective study is warranted to establish the role of exogenous factors in FHIT expression.

Pre-operative diagnosis of Meckel's diverticulum: report of a case and review of literature.

Meckel's diverticulum represents a patent omphalomesenteric duct at its junction with the ileum. Although it is a common anomaly, it is often a surgical surprise as the preoperative diagnosis is seldom established. We present an unusual case where the constellation of imaging findings was so typical that we could suggest this diagnosis prospectively and it was subsequently confirmed surgically.

Thoracic duct injury during esophagectomy: 20 years experience at a tertiary care center in a developing country.

Thoracic duct injury is an uncommon complication of esophagectomy. Experience in managing these cases is limited to large centers performing esophagectomies in good numbers. We analyzed the prospectively maintained esophageal diseases database of patients presenting to a surgical unit between 1982 and 2002. Among 552 esophagectomies during this period we had encountered 14 cases of chylothorax (2.54%). We analyzed the type and site of lesion and the impact of neoadjuvant therapy on the incidence of thoracic duct injury. Among 459 patients of transhiatal esophagectomy, 11 developed postoperative chylothorax (2.40%). In 93 transthoracic resections, there were three cases of chylothorax (3.23%; (P = 0.9185)). The incidence following preoperative radiotherapy was 2.17%. None of the 31 patients, who had undergone esophagectomy for benign diseases had developed chylothorax. In the carcinoma group the incidence in middle third lesions was 5.85% and in lower third lesions was 0.80% (P = 0.0018). Seven patients were managed conservatively. Two of these patients, for whom surgery had been planned, died before they could be taken up for surgery. In the remaining seven patients transthoracic ligation of the thoracic duct was performed. Two patients in this group died. The average hospital stay was 20 days in the conservative group and 12 days in the surgery group. Among the factors studied, patients with middle third lesions were at increased risk of developing postoperative chylothorax, when compared to upper or lower third lesions.

Effects of iron and chelation on Lake Kinneret bacteria.

The response of natural populations of bacteria (prepared by passing Lake Kinneret water through 1 µm filters) to additions of Fe(2+) and/or the chelator ethylenediaminetetraacetic acid (EDTA) was followed by measuring the incorporation of (3)H-thymidine into >0.2 µm particulates, and also by determining the increments in cell numbers after 24 h. In most cases, a stimulation of (3)H-thymidine incorporation was observed in supplemented samples relative to untreated controls after 3 and 24 h incubation. The increase in bacterial numbers was also enhanced by these supplements. Generally, EDTA alone evoked a greater stimulation than Fe(2+); combined supplements gave no further increase. This response pattern appeared consistently throughout the year in samples taken from near-surface lake waters. These results suggest that the availability of iron or chelators may play an important role in regulating bacterial metabolism and growth even in aquatic ecosystems like Lake Kinneret where ambient concentrations of total Fe are relatively high.