Two patients are described with recurrent pre-excited tachycardia and electrophysiologic characteristics typically ascribed to a nodoventricular accessory connection. The accessory pathway in each case demonstrated rate-dependent prolongation of conduction time and a low right ventricular insertion site; it was associated with a left bundle branch block configuration during pre-excitation. Intraoperatively, the pathway was demonstrated to originate at the anterior right atrioventricular (AV) anulus and not at the AV node. These data suggest that a "typical" nodoventricular pathway, by electrophysiologic criteria, may in fact be an AV pathway with AV node-like conduction properties and a distal right ventricular insertion site.

No abstract

AimsPatients with chronic heart failure (CHF) have an increased catabolic state that affects both muscle and adipose tissue (AT), and may ultimately result in cardiac cachexia. Increased plasma levels of ANP might contribute to increased lipid mobilization and oxidation in CHF. We tested the hypothesis that increased plasma ANP levels are associated with an increased catabolic (lipolytic) state of white AT in patients with CHF. Methods and resultsAfter an overnight fast, AT metabolism was studied by microdialysis in patients with CHF and healthy controls of a similar age and body composition (both n ¼ 8). AT glycolytic and lipolytic activities were assessed at rest (fasting) and after an oral glucose load (oGL). Fasting and post-prandial profiles of serum glucose, insulin, and free fatty acids and of dialysate glucose did not differ significantly between patients and controls. In contrast, fasting dialysate lactate and glycerol levels were two-fold higher in patients vs. controls (lactate, 0.51 + 0.10 and 0.26 + 0.06 mmol/L, P , 0.01; glycerol, 116 + 18 and 50 + 8 mmol/L, P , 0.001), indicating increased AT glycolytic and lipolytic rates in patients. After an oGL, dialysate lactate increased 2-and 2.5-fold, whereas dialysate glycerol decreased by 60% and 50% in patients vs. controls, but metabolite levels were always significantly higher in patients vs. controls (all P , 0.05). Plasma ANP levels were increased in patients and significantly correlated with adipose tissue dialysate glycerol. ConclusionIn patients wiuth CHF, there is a direct correlation between plasma ANP levels and increased AT catabolic (lipolytic) state. This might contribute to AT wasting and the development of cardiac cachexia in patients with CHF.--

No abstract

Aims Insulin resistance (IR) is a characteristic feature of heart failure (HF) pathophysiology that affects symptoms and mortality. Differences in the pathophysiological profile of IR in HF with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) are not characterized in detail. The aim of this study was to evaluate features of IR in HFpEF vs. HFrEF. Methods and results We included 18 patients with HFrEF (EF 30 ± 11%, body mass index (BMI) 26.5 ± 3.3 kg/m2), 22 HFpEF patients (EF 63 ± 7%, BMI 28.6 ± 4.8 kg/m2), and 20 healthy controls of similar age, all without diabetes mellitus. Patients were in stable ambulatory condition and on stable medical regimens for HF. IR was assessed at fasting steady state by the homeostasis model assessment (HOMA) index and within the physiological range of insulin–glucose interactions by the short insulin sensitivity test (SIST). Fasting‐state IR was observed in HFpEF and in HFrEF in comparison with controls (HOMA 1.9, interquartile range (IQR) 1.5–3.6 vs. HOMA 3.1, IQR 1.4–3.7 vs. controls 1.2, IQR 1.8–0.9, respectively; analysis of variance P < 0.001), but no statistical difference was observed between HFpEF and HFrEF. The dynamic test over the physiological range of insulin–glucose interactions revealed a more severe IR in HFrEF as compared with HFpEF. Thus, glucose levels remained the highest in HFrEF (76 (64–89) mg/dL) at the end of the SIST compared with HFpEF and controls (68 (58–79) and 56 (44–66) mg/dL, respectively, P < 0.001). Conclusion IR is present in non‐diabetic patients with HFpEF and HFrEF. However, distinct differences in the insulin sensitivity characteristics in HFpEF and HFrEF become apparent by more advanced testing. Patients with HFrEF showed more severe IR.