Superior two-year results of externally unsupported polyester compared to supported grafts in above-knee bypass grafting: a multicenter randomised trial.

OBJECTIVES: The aim of this study was to compare externally supported thin wall knitted polyester (P-EXS) and externally unsupported thin wall knitted polyester (P-non-EXS) for above-knee (AK) femoro-popliteal bypass grafting. DESIGN: A prospective multicenter randomised clinical trial. MATERIAL AND METHODS: Between 1999 and 2008, 265 AK femoro-popliteal bypass grafts (6 mm in diameter) were performed, including 136 P-EXS and 129 P-non-EXS. The selection of patients was based on the presence of disabling claudication or critical ischaemia. Follow-up took place at 3, 6, 12, 18, and 24 months and included clinical examination and duplex ultrasonography. The main end points of this study were primary patency rates at one and two years. Secondary end points were mortality, and primary assisted and secondary patency rates. Cumulative patency rates were calculated with life-table analysis and log-rank testing. RESULTS: The 1-year primary, primary assisted and secondary patency rates were 65%, 70% and 84%, respectively, for P-EXS and 76% (p = 0.05), 82% (p = 0.03) and 88% (p = 0.35), respectively, for P-non-EXS. Two-year primary, primary assisted and secondary patency rates were 45%, 57% and 70%, respectively, for P-EXS and 62% (p = 0.003), 75% (p = 0.005) and 84% (p = 0.02), respectively, for P-non-EXS. The overall mortality rate after two years was 11.3%. CONCLUSION: In above-knee femoro-popliteal bypass grafting patency rates of externally supported knitted polyester grafts were inferior to their unsupported counterpart. ISRCTN: At the time this study started this number was not the standard.

Diagnostic and therapeutic approach of congenital solitary coronary artery fistulas in adults: Dutch case series and review of literature.

BACKGROUND: Coronary artery fistulas (CAFs) are infrequent anomalies, coincidentally detected during coronary angiography (CAG). AIM: To elucidate the currently used diagnostic imaging modalities and applied therapeutic approaches. MATERIALS AND METHODS: Five Dutch patients were found to have CAFs. A total of 170 reviewed subjects were subdivided into two comparable groups of 85 each, treated with either percutaneous 'therapeutic' embolisation (PTE group) or surgical ligation (SL group). RESULTS: In our series, the fistulas were visualised with several diagnostic imaging tests using echocardiography, multidetector computed tomography, and CAG. Four fistulas were unilateral and one was bilateral; five originated from the left and one originated from the right coronary artery. Among the reviewed subjects, high success rates were found in both treatment groups (SL: 97% and PTE: 93%). Associated congenital or acquired cardiovascular disorders were frequently present in the SL group (23%). Bilateral fistulas were present in 11% of the SL group versus 1% of the PTE group. The fistula was ligated surgically in one and abolished percutaneously in another. Medical treatment including metoprolol was conducted in two, and watchful waiting follow-up was performed in one. CONCLUSIONS: Several diagnostic imaging techniques are available for assessment of the anatomical and functional characteristics of CAFs.

Endovascular treatment of chronic splanchnic syndrome.

OBJECTIVE: The technical and clinical outcome of endovascular revascularization was analyzed in patients with suspicion of chronic splanchnic syndrome (CSS). METHODS: Medical history, duplex, angiography and exercise gastric tonometry suggested CSS in 97 patients. Twenty-seven of them were treated endovascular (one patient had 3-vessel, 12 patients had 2-vessels, 14 patients had 1-vessel CSS). Five patients received previous splanchnic revascularization. Twenty-three patients (85%) had severe co-morbidity: cardiac, pulmonary or cachexia. Endovascular treatment consisted of percutaneous transluminal angiography (PTA) of the coeliac artery (CA) or superior mesenteric artery (SMA) in three and primary balloon expandable stenting in 24 patients (13 CA and 10 SMA solitary, two CA and SMA both, 31 splanchnic arteries in total). RESULTS: Three patients showed procedure related complications (11%). Mean follow-up was 19, range 2-76 months. Two patients died during follow up, both not procedure or CSS related. Five patients had no improvement of symptoms, without evidence of re- or residual stenosis. The primary clinical success was 67%, secondary clinical success was 81%. The primary patency was 81% and secondary patency was 100%. CONCLUSION: Endovascular treatment of CSS has a reasonable outcome. It is an alternative to operative treatment, especially in patients with high co-morbidity or limited life expectancy.

The use of an episiotomy in relation to the professional education of the delivery attendant.

In a group of 1272 primiparous women, who delivered spontaneously at the University Hospital of Leiden between 1 January 1988 and 31 December 1991, the relationship between the use of an episiotomy and the professional training of the delivery attendant has been studied, using multiple logistic regression (a random effects model to allow for patient-within-physician effects). The following factors were taken into account: birthweight, duration of the second stage of labour, supposed fetal distress, age and race of the mother, gestational age, duration of pregnancy and the year of the delivery. Based on the logistic regression model it is estimated that registrars and gynaecologists are 2.5 and 3.4 times, respectively, more likely than midwives to perform an episiotomy.

A versatile alginate droplet generator applicable for microencapsulation of pancreatic islets.

Alginate beads for immunoisolation of pancreatic islets by microencapsulation should be small, smooth, and spherical in order to ensure that around the islets a strong alginate-polylysine-alginate capsule will be formed with optimal biocompatibility and diffusion of nutrients and hormones. However, the preparation of small capsules around islets is difficult. Our newly designed air jet droplet generator allows for variations in the length and diameter of the alginate nozzle and the air jacket and is in this way adaptable to a required bead size. Alginate droplets are converted into rigid beads in a 100 mM CaCl 2 solution. Their size depends upon the diameter of the jacket, the air flow rate, and the outer diameter of the nozzle, whereas the production rate depends upon the pressure on the alginate, and on the diameter and the length of the nozzle. When the air flow or the alginate flow surpasses a certain rate, the droplets are fragmented. This study describes the mutual relationship of these variables and defines their optimal range for reproducible production of smooth and spherical beads for microencapsulation of islets at an acceptable production rate.