Left atrial maze procedure: a useful addition to other corrective operations

BACKGROUND: The left atrial maze procedure is performed to treat atrial fibrillation (AF), mainly in patients with mitral valve disease. In this study, we assessed the midterm results of this procedure and clinically analyzed predicting factors for postoperative persistent AF. METHODS: From June 1997 to May 2001, the left atrial maze procedure was performed on 31 patients (29 with mitral valve disease and 2 lone AF). For purposes of analysis, patients were divided postoperatively into those with persistent atrial fibrillation (AF) and those with sinus rhythm (SR), except 2 patients who required pacemaker implantation for sinus node dysfunction. Over a follow-up period of more than 12 months, patients were compared based on their preoperative and intraoperative variables. RESULTS: At discharge, the success rate was 89.7%. The midterm rates (total of 94.9 patient-years of follow-up) of sinus rhythm and freedom from AF were 72.4% and 79.3%, respectively. There were significant differences in duration of AF, voltage of f-wave at first precordial lead of electrocardiogram, and cardiothoracic ratio between the SR and AF groups. CONCLUSIONS: Our midterm results suggest that the left atrial maze procedure is an effective alternative adjunct procedure for elective open heart surgery to treat AF, depending upon the patient's clinical condition.     

Calcineurin homologous protein isoform 2 (CHP2), Na+/H+ exchangers-binding protein,is expressed in intestinal epithelium

The Na+/H+ exchangers (NHEs) comprise a family of membrane proteins that catalyze the electroneutral exchange of Na+ and H+. Calcineurin homologous protein (CHP) acts as a crucial cofactor for NHE activity through direct interaction with the carboxyl-terminal tail region of NHEs. We have cloned a new rat CHP isoform (rCHP2) and characterized the binding property to NHEs and the tissue distribution. rCHP2 binds to the juxtamembrane region of plasma membrane-type NHE isoforms (NHE1-5) in vivo and in vitro as well as rCHP1 (original rat CHP). Interestingly, CHP2 is predominantly expressed in the small and large intestine although rCHP1 shows relatively ubiquitous expression at both the mRNA and protein levels. In situ hybridization experiments demonstrated the abundant expression of CHP2 in the epithelial cell layer of villi of the small intestine in contrast with the expression of CHP1 in both the epithelial layer and connective tissues. These results suggest that CHP2 functions in the absorptive epithelium for the intestine with NHE(s).     

Prospective study of thoracoscopic limited resection for ground-glass opacity selected by computed tomography

BACKGROUND: With recent advances in low-dose helical computed tomography (CT), detection of ground-glass opacity (GGO) has increased. The aim of this study was to correlate high-resolution CT (HRCT) findings with pathologic features and to evaluate the efficacy of thoracoscopic limited resection for focal GGO, which were selected based on HRCT findings. METHODS: Focal GGO lesions were classified into two subtypes based on HRCT findings: pure type and mixed type. Ninety-six patients with persistent GGO 2 cm or less in diameter underwent pulmonary resection from January 1997 to December 2001. Among these, thoracoscopic wedge resection was performed prospectively between June 2000 and December 2001 in 33 patients with pure GGO lesions that were 1 cm or less. RESULTS: Thoracoscopic wedge resection was completed with complete safety. The histologic diagnoses of these 33 lesions were adenocarcinoma in 1, bronchioloalveolar carcinoma (BAC) in 23, and atypical adenomatous hyperplasia (AAH) in 9. No patients have had any evidence of tumor recurrence to date. Of the total 96 GGO lesions, 93.0% (53/57) of pure GGO 1 cm or less were BAC or AAH, whereas 38.5% (15/39) of pure GGO larger than 1 cm or mixed GGO were adenocarcinoma. CONCLUSIONS: Pure GGO 1 cm or less was characteristic of noninvasive lesions. Thoracoscopic limited resection for small GGO lesions selected by HRCT was valid.     

Decrease in anticoagulant factors in patients with prostate cancer treated with diethylstilbestrol diphosphate

PURPOSE: Estrogen has been highly evaluated as one of the most potent endocrine agents for the treatment of prostate cancer. Unfortunately, a high risk of cardiovascular complications is a clinically important adverse effect of estrogen therapy, and occasionally the complications are fatal. In recent years a high incidence (55%) of thrombotic events has been reported in patients with congenital protein S (PS) deficiency. The aim of this study is to determine the relationship between cardiovascular complications of estrogen therapy and anticoagulant factor levels in the serum of patients with prostate cancer. MATERIALS AND METHODS: Study 1 employed 99 patients with prostate cancer: 39 were untreated, 25 were treated with LH-RH agonist therapy alone, and 35 were treated with oral diethylstilbestrol diphosphate (DESdP) 300 mg per day. We measured the serum levels of anticoagulant factors, parameters antithrombin III (ATIII), protein C (PC), PS, coagulant and fibrinolytic factors in all patients. In study 2, the adverse effects of DESdP therapy on the serum levels of anticoagulant factors were examined in 8 patients with advanced prostate cancer. RESULTS: In study 1, the ATIII and PS levels of the patients treated with estrogen therapy were significantly lower than those in either the untreated patients or the patients treated with an LHRH agonist alone. Especially, both PS antigen (51.5 +/- 16.0%) and PS activity (42.9 +/- 16.0%) were markedly lower in estrogen-treated patients than in the untreated patients (102 +/- 20.8%, 100.6 +/- 20.7%, respectively) or the patients treated with an LH-RH agonist alone (97.9 +/- 16.8%, 91.5 +/- 17.7%, respectively, both p < 0.0001). PS was decreased to below the normal lower limit of normal in 82% (24/35) of the patients on estrogen therapy. In study 2, all 8 cases showed a significant decrease in PS after DESdP therapy. CONCLUSIONS: Our results showed that the PS levels in the oral DESdP group were almost the same as in patients with congenital PS deficiency. We conclude that decreased PS may play a role in the development of cardiovascular complications in prostate cancer patients on estrogen therapy.     

Sling suspension of the liver in donor operation: a gradual tape-repositioning technique

BACKGROUND: To control bleeding in the deeper parenchymal plane in right hepatectomy, Belghiti et al. (J Am Coll Surg 2001;193:109) proposed a liver-hanging maneuver using a sling passed between the anterior surface of the inferior vena cava (IVC) and the liver parenchyma. We applied this technique in donor operations in which a hepatic parenchymal transection should be performed before dividing the feeding or draining vessels for the graft. METHODS: After passing a tape between the liver and the IVC, the lower tip of the tape is pulled up behind the hepatic hilum to enable effective traction of the dorsal part of the liver. To preserve significant middle hepatic vein (MHV) tributaries in right-liver graft, the tape is gradually repositioned behind the veins, and parenchymal transection is completed before dividing the venous tributaries. Congestion of the graft is minimal until harvest. In right hepatectomy with the MHV, the tape is switched behind the MHV to preserve the MHV. RESULTS: Since March 2000, this technique has been used in 71 consecutive donor operations, including 37 right hepatectomies without the MHV, 8 right hepatectomies with the MHV, 20 left hepatectomies with the caudate lobe, and 6 right lateral sectorectomies. Taping behind the liver was successful in all but one donor (98.6%). There were no major complications related to this procedure. CONCLUSIONS: This new approach to the sling suspension of the liver with a gradual tape manipulation facilitated the suspending action and was useful in four types of donor operation. These techniques are feasible in most living donors and are recommended as basic procedures to enhance the safety of the donor and the quality of the graft.     

A case responding to weekly paclitaxel (TXL) therapy as third line chemotherapy for scirrhous type gastric cancer

A 67-year-old female was admitted to our hospital in May, 2001 for examination. She was diagnosed with advanced gastric cancer that was inoperable due to peritoneal dissemination. Seventeen courses of sequential MTX and 5-FU therapy, and 2 courses of TS-1 plus CDDP were carried out. A partial response (PR) and prolonged NC were obtained after these chemotherapies. However, pleural effusion and ascites appeared again, and we diagnosed progressive disease. As a third line chemotherapy for this patient, paclitaxel (TXL) was administered. Treatment consisted of two 3-week courses of paclitaxel 70 mg per m2 on day 1 of each week, with a 1-week break between the courses. Two weeks after the start of this therapy, pleural effusion and ascites had completely disappeared. Paclitaxel is considered to be promising for advanced gastric cancers, as second or third line chemotherapy with paclitaxel for patients with inoperable gastric cancer seems to be effective in improving QOL.     

Des-gamma-carboxy prothrombin in cancer and non-cancer liver tissue of patients with hepatocellular carcinoma

Des-gamma-carboxy prothrombin (DCP), also known as protein induced by vitamin K absence or antagonist II absence (PIVKA-II), has been considered as a useful serum tumor marker for hepatocellular carcinoma (HCC). However, the underlying mechanism causing the elevation of serum DCP levels in HCC patients remains unclear. This study was undertaken to identify the relationship between serum DCP levels and the expression of DCP in cancer and surrounding non-cancer liver tissues of HCC patients. Serum and tissue samples prepared from 92 patients with a single HCC nodule were subjected to clinicopathological study by measuring serum DCP levels and performing immunohistochemical staining for tissue DCP. Serum DCP levels correlated significantly with clinicopathological factors such as hepatitis markers, tumor differentiation, vascular invasion, intrahepatic metastasis, TNM stage, tumor size, tumor recurrence, and patient survival. DCP immunohistochemical staining was positive in cancer tissues for 68 (68/92, 73.9%) patients and in non-cancer tissues surrounding tumors for 24 (24/92, 26.1%) patients. There was no apparent correlation between serum DCP values and the expression of DCP in HCC tissues; however, there was a significant correlation between serum DCP levels and the expression of DCP in non-HCC tissues (p=0.0398). In conclusion, our results suggest that the origin of elevated serum DCP may lie not only in HCC tissue but also in non-cancer tissues. The HCC lesion itself appears to influence the production of DCP in surrounding non-cancer tissues.