Effects of heart rate on phasic Y-graft blood flow and flow reserve in patients with complete arterial myocardial revascularizaton: an intravascular Doppler catheter study.

OBJECTIVE: It is not well established whether the blood flow of arterial composite Y-grafts can efficiently respond to the flow demand of the coronary system early postoperatively. The aim of this study was to evaluate if soon after the operation, arterial composite Y-grafts can increase blood flow in response to an increase in myocardial oxygen consumption (MVO2). METHODS: Twenty-seven patients who received complete arterial myocardial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) as composite Y-graft gave their consent to a pre-discharge coronary angiography and intravascular flow velocity measurements using a Doppler guide wire. Flow measurements were performed in the LITA main stem, the distal LITA and the RA, both at rest and during atrial pacing at the 85% of the patient age-predicted maximum. The heart rate-systolic blood pressure product was considered as an indirect index of MVO2. Hyperemic flow was determined after injection of adenosine. The flow reserve (FR) was defined as the ratio of blood flow during maximal hyperemia (Qmax) to baseline flow (Qbasal). RESULTS: Atrial pacing increased MVO2 significantly (P<0.000). None of the patients developed ischemic S-T segment modifications or complained of chest pain. Q(basal) increased significantly in the LITA main stem (P=0.001), distal LITA (P=0.041) and RA (P=0.004) while Qmax did not change significantly. As a consequence, the FR decreased in the LITA main stem (P=0.002), distal LITA (P<0.000) and RA (P<0.000) but was not completely exhausted. CONCLUSIONS: Soon after the operation, arterial composite Y-grafts can significantly increase blood flow in response to conditions of increased MVO2, keeping normal the myocardial O2 supply-to-demand ratio.     

Image quality on dual-source computed-tomographic coronary angiography

Multi-detector CT reliably permits visualization of coronary arteries, but due to the occurrence of motion artefacts at heart rates >65 bpm caused by a temporal resolution of 165 ms, its utilisation has so far been limited to patients with a preferably low heart rate. We investigated the assessment of image quality on computed tomography of coronary arteries in a large series of patients without additional heart rate control using dual-source computed tomography (DSCT). DSCT (Siemens Somatom Definition, 83-ms temporal resolution) was performed in 165 consecutive patients (mean age 64 +/- 11.4 years) after injection of 60-80 ml of contrast. Data sets were reconstructed in 5% intervals of the cardiac cycle and evaluated by two readers in consensus concerning evaluability of the coronary arteries and presence of motion and beam-hardening artefacts using the AHA 16-segment coronary model. Mean heart rate during CT was 65 +/- 10.5 bpm; visualisation without artefacts was possible in 98.7% of 2,541 coronary segments. Only two segments were considered unevaluable due to cardiac motion; 30 segments were unassessable due to poor signal-to-noise ratio or coronary calcifications (both n = 15). Data reconstruction at 65-70% of the cardiac cycle provided for the best image quality. For heart rates >85 bpm, a systolic reconstruction at 45% revealed satisfactory results. Compared with earlier CT generations, DSCT provides for non-invasive coronary angiography with diagnostic image quality even at heart rates >65 bpm and thus may broaden the spectrum of patients that can be investigated non-invasively.     

Quantitative diagnostic performance of myocardial perfusion SPECT with attenuation correction in women.

Attenuation correction (AC) for myocardial perfusion SPECT (MPS) had not been evaluated separately in women despite specific considerations in this group because of breast photon attenuation. We aimed to evaluate the performance of AC in women by using automated quantitative analysis of MPS to avoid any bias. METHODS: Consecutive female patients--134 with a low likelihood (LLk) of coronary artery disease (CAD) and 114 with coronary angiography performed within less than 3 mo of MPS--who were referred for rest-stress electrocardiography-gated 99mTc-sestamibi MPS with AC were considered. Imaging data were evaluated for contour quality control. An additional 50 LLk studies in women were used to create equivalent normal limits for studies with AC and with no correction (NC). An experienced technologist unaware of the angiography and other results performed the contour quality control. All other processing was performed in a fully automated manner. Quantitative analysis was performed with the Cedars-Sinai myocardial perfusion analysis package. All automated segmental analyses were performed with the 17-segment, 5-point American Heart Association model. Summed stress scores (SSS) of > or =3 were considered abnormal. RESULTS: CAD (> or =70% stenosis) was present in 69 of 114 patients (60%). The normalcy rates were 93% for both NC and AC studies. The SSS for patients with CAD and without CAD for NC versus AC were 10.0 +/- 9.0 (mean +/- SD) versus 10.2 +/- 8.5 and 1.6 +/- 2.3 versus 1.8 +/- 2.5, respectively; P was not significant (NS) for all comparisons of NC versus AC. The SSS for LLk patients for NC versus AC were 0.51 +/- 1.0 versus 0.6 +/- 1.1, respectively; P was NS. The specificity for both NC and AC was 73%. The sensitivities for NC and AC were 80% and 81%, respectively, and the accuracies for NC and AC were 77% and 78%, respectively; P was NS for both comparisons. CONCLUSION: There are no significant diagnostic differences between automated quantitative MPS analyses performed in studies processed with and without AC in women.     

MR-guided liver biopsy within a short, wide-bore 1.5 Tesla MR system

The purpose of this study was to evaluate the diagnostic efficacy of magnetic resonance (MR)-guided biopsy of focal liver lesions within a short, wide-bore 1.5-T MR system and to determine the duration and accuracy of needle placement using MR fluoroscopy guidance in 25 patients. Accuracy of needle placement was evaluated in two orthogonal planes, and the out-of-plane angle of needle deflection was measured. Needle positioning was characterised subjectively as centred, peripheral, or exterior relative to the lesion. Exterior positioning was corrected by a step-by-step procedure. Surgical resection (n = 6), previous histologies (n = 8), or clinical/radiological follow-up (n = 11) served as the ‘gold standard’. The guidance needle could be placed successfully using MR fluoroscopy in 20 of 25 patients (80%). Needle placement was rated as ‘centred’ in 11 and as ‘peripheral’ in nine patients. Median needle deflection was 2.6 degrees, with a median deviation of 3.4 mm. In five patients, the direct approach failed or was rated as ‘exterior’; therefore, repositioning after needle stabilisation with a stainless-steel stylet was necessary. The diagnostic yield of all biopsies was: sensitivity 95.5%, specificity 100.0% and accuracy 96.0%. In conclusion, MR-guided biopsies in a short, wide-bore MR system yielded highly reliable biopsy results, and in most cases the direct approach with MR fluoroscopy guidance proved to be fast and accurate.     

Right living donor liver transplantation: an option for adult patients: single institution experience with 74 patients

OBJECTIVE: To present an institutional experience with the use of right liver grafts in adult patients and to assess the practicability and efficacy of this procedure by analyzing the results. SUMMARY BACKGROUND DATA: Living donor liver transplantation (LDLT) for the pediatric population has gained worldwide acceptance. In the past few years, LDLT has also become feasible for adult patients due to technical evolution in hepatobiliary surgery and increased experience with reduced-size and split-liver transplants. Nevertheless, some graft losses remain unexplained and are possibly due to unrecognized venous outflow problems. METHODS: From April 1998 to September 2002, we performed 74 right LDLTs (segments 5-8). The 74 donors were selected from 474 candidates according to standard protocol. The median age of the donors was 35 years (range 18-58 years) and 51 years (range 18-64 years) in recipients. Standard and extended indications for transplantation were considered. Over the period reported, technical modifications in the bile duct anastomosis (duct-to-duct, end-to-end, or end-to-side) and a new graft implantation technique that provides maximized venous outflow, leading to outcome improvement, were developed. RESULTS: 64.9% of patients had liver cirrhosis and 35.1% had malignancy. While 44 donors (59.5%) presented an uneventful postoperative course, 27% minor (pleural effusion, pneumonia, venous thrombosis, wound infection, incisional hernia) and 13.5% major (biliary leakage, death of a donor due to unrecognized hereditary liver disease, and consecutive liver insufficiency) complications were documented. In recipients, 23% biliary complications and 6.8% hepatic artery thrombosis occurred. The overall patient and graft survival rate after 1 year was 79.4% and 75.3%, respectively. In cases with extended indication, the patient survival rate was 74% and the graft survival rate 68% at 12 months. Using technical modifications in the last 10 recipients, including 2 critically decompensated cirrhotics, the survival rate was 100% at a median follow-up of 3.5 months. CONCLUSIONS: In our transplant program, living donor liver transplantation has become a standard option in the adult patient population. The critical issue of this procedure is donor morbidity. Technical improvements in the harvesting and implantation of right grafts can also offer hope to patients with challenging forms of end-stage liver disease or malignant liver tumors.     

Glial cell-derived neurotrophic factor upregulates the expression and activation of matrix metalloproteinase-9 in human pancreatic cancer

BACKGROUND: We have previously reported that the glial cell-derived neurotrophic factor (GDNF) promotes pancreatic cancer cell invasion in vitro. The purpose of this study was to determine whether GDNF regulates the expression and activation of matrix metalloproteinase-9 (MMP-9) in human pancreatic cancer cells. METHODS: We used human pancreatic cancer cell line MIA PaCa-2. The effect of GDNF on mRNA and protein expression was measured by Northern blot, Western blot and enzyme-linked immunosorbent assay. MMP proteolytic activity was detected by gelatin zymography. To determine which intracellular pathways were involved, we used the following inhibitors: tyrosine kinase inhibitor Genistein, MEK-1 inhibitor PD98059 and PI3-K inhibitor Wortmannin. RESULTS: GDNF increased MMP-9 mRNA and protein expression in MIA PaCa-2 cells in a dose-dependent manner. Treatment with GDNF enhanced gelatinolytic activity of the pro and active form of MMP-9. Inhibitor experiments showed that the expression and activity of pro MMP-9 was totally inhibited by Genistein and partially by Wortmannin, whereas PD98059 had no effect. All three compounds inhibited the activity of the active form of MMP-9. CONCLUSIONS: GDNF upregulates the expression and enzymatic activity of MMP-9 through different signaling pathways in MIA PaCa-2. These findings suggest that GDNF modulates MMP-9 expression and activation, and this may promote pancreatic cancer invasion.     

Laparoscopic Treatment of Gastric <Emphasis Type="SmallCaps">Gist</Emphasis>: Report of 21 Cases and Literature’s Review

Background Although the feasibility of laparoscopic resection of gastric gastrointestinal stromal tumors (GISTs) has been established, various aspects are debated. This paper describes the problems of minimally invasive resection of gastric GISTs and compares this experience with an extensive literature review. Study Design Between August 2001 and December 2006, 21 consecutive patients undergoing laparoscopic resection of gastric GISTs were enrolled in a prospective study. A literature review of laparoscopic treatment was performed on Pubmed using keywords GIST and surgery. A comparison with authors’ experience with open wedge-segmental resection of GISTs (25 cases from November 1995 to December 2000) was also carried out. Statistical analysis was based on chi-squared test and t Student evaluation. Results Twenty-one patients, mean age 50.1 years (range, 34–68 years), were submitted to laparoscopic wedge- segmental gastric resections. Mean tumor size was 4.5 cm (range, 2.0–8.5 cm). Mean operative time was 151 min (range, 52–310 min), the mean blood loss was 101 mL (range, 10–250 mL), and the mean hospital stay was 4.8 days (range 3–7 days). There were no major operative complications or mortalities. All lesions had negative resection margins. At a mean follow-up of 35 months, all patients were disease-free. Morbidity, mortality, length of stay, and oncologic outcomes were comparable to the open surgery retrospective evaluation (p = not significant). Conclusions As found also in the literature review, the laparoscopic resection is safe and effective in treating gastric GISTs. Given these findings as well as the advantages afforded by laparoscopic surgery, a minimally invasive approach should be the preferred surgical treatment in patients with small- and medium-sized gastric GISTs.     

Radiofrequency ablation prior to liver transplantation: focus on complications and on a rare but severe case

Abstract: Background: Radiofrequency ablation (RFA) is an established treatment for hepatocellular carcinoma (HCC) in patients awaiting liver transplantation, due to its comparably low rate of complication and high effectiveness. Complications are thought to be rare and mostly self-limiting. By contrast, we report on a life-threatening complication and discuss it in the context of other complications. Patients and methods: Out of a total of 149 RFA procedures, the incidence of major complications was 4% on a per-procedure basis. Mortality was 0.67%. Major complications included intractable pain, intrahepatic hematoma, skinburn at the site of patch electrode, and sectorial bile duct stricture. All complications occurred after percutaneous RFA. Highlighted is a young patient listed for liver transplantation because of HCC recurrence following hepatic resection, who was treated by percutaneous RFA as a bridging therapy until a suitable graft became available. Post-operatively, gastric perforation occurred due to heat injury of the gastric wall. Conclusions: The percutaneous RFA approach can occasionally lead to detrimental complications, particularly in patients with intra-abdominal adhesions, due to previous surgery if new intrahepatic malignant lesions accrue near the resection margin. Even widespread HCC disease can be treated effectively with orthotopic liver transplantation if the tumor growth is limited to the liver.     

Preoperative administration of controlled-release oxycodone as a transition opioid for total intravenous anaesthesia in pain control after laparoscopic cholecystectomy

Background  The complexity of pain from laparoscopic cholecystectomy and the need for treating incident pain provide rationale for multipharmacological analgesia. We investigated the preoperative administration of controlled-release (CR) oxycodone as transition opioid from remifentanil infusion for pain after laparoscopic cholecystectomy. Methods  Fifty consecutive patients undergoing laparoscopic cholecystectomy were randomly, double-blindly assigned to treatment group (n = 25, CR oxycodone: 1 h before surgery and 12 h after the first administration) or to the control group (n = 25, placebo: administered at the same intervals). General anaesthesia was maintained with propofol and remifentanil target-controlled infusions (TCIs). All patients received ketorolac 30 mg i.v. Tramadol i.v. was administered for patient-controlled analgesia (PCA) postoperatively. Numerical rating scale for pain at rest and at movement (NRSr and NRSi), tramadol consumption, times to readiness to surgery and awakening, times to modified Aldrete’s and modified Post-Anesthetic Discharge Scoring System (PADSS) >9 and side effects were evaluated. Results  All NRSr and NRSi and tramadol consumption were significantly lower in the treatment group. The oxycodone group showed higher modified Aldrete’s scores at each time and reached a PADSS >9 faster. Side effects and postoperative nausea and vomiting episodes were comparable. Conclusions  We demonstrated the success of a multipharmacological treatment including opioid premedication with CR oxycodone used as transition opioid for TCI remifentanil infusion; the treatment group showed lower pain scores and rescue analgesic consumption, shorter time to discharge from recovery room and from surgical ward, and the same incidence of side effects, comparably to controls. Sources of financial support for the work: University of Parma, viale Gramsci 14, 43100 Parma PR, Italy.     

Advantages of multidisciplinary management of bile duct injuries occurring during cholecystectomy

BACKGROUND: The aim of the present study was to highlight the advantages of treatment of bile duct injury (BDI) occurring during cholecystectomy on the basis of a multidisciplinary cooperation of expert surgeons, radiologists, and endoscopists. METHODS: Sixty-six patients had major BDIs or short- or long-term failures of repair. BDI was diagnosed intraoperatively in 27 patients (40.9%) and postoperatively in 39 (59.1%) patients. Among referred patients, 30 had complications from bile leak, 15 from obstructive jaundice, and 20 from recurrent cholangitis. Two patients died from sepsis after delayed referral before repair was attempted. Eleven additional patients had minor BDIs with bile leak both with and without choleperitoneum. RESULTS: Of patients with major BDI, surgical repair was performed in 41 (64.1%). Postsurgical morbidity rate was 15.8%, and there was no mortality. The rate of excellent or good results after surgical repair was 78.0% (32 of 41 patients), and this increased to 87.8% (36 of 41 patients) by continuing treatment with stenting in postsurgical strictures. Biliary stenting alone was performed in 23 patients (35.9%), with excellent or good results in 17 (73.9%). More than 200 endoscopic and percutaneous procedures were performed for initial assessment, treatment of sepsis, nonsurgical repair, contribution to repair, and follow-up. Patients with minor BDIs underwent various combinations of surgical and endoscopic or percutaneous treatments, always with good results. CONCLUSIONS: A multidisciplinary approach was of paramount importance in many phases of treatment of BDI: initial assessment, treatment of secondary complications, resolution of sepsis, percutaneous stenting before surgical repair, dilatation of strictures after repair, final treatment in patients not repaired surgically, and follow-up.