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Background: Insulin has to be transported across the capillary endothelium to stimulate muscle glucose uptake. We investigated insulin uptake from the peripheral circulation in non-diabetic (ND) individuals and in type 2 diabetes (T2D) patients., Methods: Single-center cross-sectional study involving 40 ND (age 65±11 years) and 30 T2D patients (age 67±8 years). Thirty-six participants were studied in the fasted state (22 ND subjects and 14 T2D patients termed NDF and T2DF) and 34 participants 1-h following a glucose challenge (18 ND subjects and 16 T2D patients indicated as NDG and T2DG). Main outcome measure was fractional extraction (FE) of insulin (FEins) and glucose using the forearm balance method., Results: In NDF, FEins was 18 (10-26) % at lower insulin levels (63 51-80] pmol/l), while in NDG at higher insulin levels (776 [543-1176] pmol/l), FEins was 9 (4-16) % (p = 0.01 vs. NDF). In NDF only, a negative correlation was observed between FEins and arterial plasma insulin load (rho = - 0.575;p = 0.006) and fasting plasma glucose levels (rho = - 0.551;p = 0.01). In T2DF FEins was 6 (1-19) % and not different from FEins in T2DG (10 2-14) %), and was not associated to fasting glucose. FEins tended to be higher in NDF compared to T2DF (p = 0.07)., Discussion: We propose that in ND individuals, besides passive diffusion, an active high-affinity pathway with limited capacity around lower physiologic insulin levels exists for insulin transendothelial transport, contributing to glycemic control. In T2D patients, this mechanism of peripheral insulin uptake is diminished or even absent. Modulation of insulin extraction from the circulation may be a novel target to improve glucose metabolism in T2D., Competing Interests: No conflict of interest has been declared by the authors., (© Georg Thieme Verlag KG Stuttgart · New York.)

Unlabelled: To evaluate the indications, underlying cardiac disorders, efficacy and complications involved with implantable cardioverter-defibrillators (ICDs) in paediatric patients in The Netherlands, the records of all patients aged 18 years or younger who underwent ICD placement were reviewed retrospectively. Between January 1995 and September 2002, 23 patients (11 males, 12 females; median age 12 years, range 6 months to 16 years) underwent ICD implantation. The ICD was implanted for aborted sudden cardiac death ( n = 14), syncope ( n = 5) or for primary prevention of sudden cardiac death ( n = 4). Underlying cardiac disorders were electrical diseases ( n = 16), hypertrophic or dilated cardiomyopathy ( n = 4) and congenital cardiac malformations ( n = 3). Five patients had an epicardially placed ICD, while 18 underwent a transvenous approach. The generator was placed in an abdominal position in eight patients, whereas it was placed in the subpectoral region in 15. There was no early mortality. Median hospital stay was 5 days (range 2-30 days). Median follow-up time was 29 months (range 1 month to 7 years). Seven patients experienced an inappropriate shock after a median period of 7 months; five patients an appropriate shock after a median period of 3 months. The reasons for inappropriate shock were supraventricular tachycardia ( n = 1), sinus tachycardia ( n = 4) or T-wave sensing (n = 2). One patient with malignant long QT syndrome died of intractable arrhythmias and irreversible cardiomyopathy. Generator replacement was necessary in four patients after 28, 44, 51 and 54 months respectively., Conclusion: Implantable cardioverter-defibrillator implantation in paediatric patients is a safe procedure with a good medium-term outcome. The most serious problem is the occurrence of a significant number of inappropriate shocks.

Aims: The aim of this study was prospectively to compare clinical practice of implantable cardioverter defibrillator (ICD) use with current guidelines in out-of-hospital cardiac arrest (OHCA) survivors., Methods and Results: From January 2000 till March 2002, 70 consecutive patients (pts) discharged from 15 hospitals after OHCA, with ventricular fibrillation (VF) as initial rhythm were included. Documentation of diagnosis, left ventricular function, ischaemia, electrophysiological studies (EPS), and decisions regarding ICD implantation were obtained from medical records. An expert committee compared these data with current guidelines. According to these guidelines 18 pts (26%) had an ICD indication and received an ICD while 37 pts (53%) had no indication and did not receive an ICD. In 13 pts without acute myocardial infarction insufficient diagnostic procedures were performed to permit a decision on ICD indication, hence no ICD was implanted. Two pts had an ICD indication but did not receive an ICD. During the follow-up with duration of 25 months (range 12-38 months), two sudden deaths occurred in the group of pts without an ICD. Of the pts with an ICD, 4 pts (22%) were reported to have received one or more shocks for VT/VF., Conclusion: In at least 21% of OHCA survivors, insufficient diagnostic procedures concerning the indication for ICD implantation were performed or no ICD was implanted when indicated, despite clear guidelines. In particular, there was no proof of ischaemia prior to revascularization and no confirmation of the absence of ischaemia and EPS thereafter. Clinicians should be guided better in evaluating pts after OHCA concerning the indication for ICD implantation, especially when a transient of reversible condition was present or when treatment was sufficiently established safely to refrain from ICD implantation., (Copyright 2004 The European Society of Cardiology)