Spatiotemporal electrocardiographic characterization of ventricular depolarization and repolarization abnormalities in long QT syndrome

Background and Purpose

If only a standard electrocardiogram (ECG) is available, at least 25% of patients with long QT syndrome (LQTS) may be missed. Our goal is to quantify abnormal electrical activity and to develop an ECG decision rule for the patients with LQTS.

Methods

One hundred forty-one subjects were included in this study (71 patients with LQTS and 70 healthy subjects). A 12-lead digital ECG was recorded for each subject and analyzed using the CAVIAR (comparative analysis of ECG-VCG and their interpretation with auto-reference to the patient) method.

Results

A decision tree involving criteria based on 3 spatiotemporal ECG measurements—the QT interval and the maximum amplitude of the T wave, both corrected from heart rate, and the loss of planarity of the end of QRS—identified patients with LQTS from healthy subjects with a sensitivity of 89%, a specificity of 96%, and a total accuracy of 92%.

Conclusions

This study suggests that 3-dimensional ECG analysis may improve the detection of patients with LQTS.     

Growth hormone to improve short bowel syndrome intestinal autonomy: a pediatric randomized open-label clinical trial

Background: The ability of growth hormone (GH) to promote the weaning‐off of parenteral nutrition (PN) in short bowel syndrome (SBS) is unclear. No randomized controlled study is available in children. This study was undertaken to determine if GH could enhance the weaning off of PN in PN‐dependent children with SBS. Methods: A prospective randomized open‐label multicenter study was performed in 14 patients (mean age, 9 ± 1.4 years) with SBS (average small bowel length, 33 cm) and long‐term PN dependency (8 years) on an unrestricted diet. A standardized PN decrease with and without GH (0.14 mg/kg/d) was conducted. The patients were randomized to either a GH group (4 months of GH) or a control (CTR) group (4 months without GH, followed by 4 months with GH). Blood tests and a nutrition assessment of enteral and parenteral intakes were performed. Groups were compared with the Wilcoxon test. Results: Treatment with GH did not improve the weaning off of PN (decrease in PN caloric intake of 32.5% ± 9.6% in the GH group vs 35.2% ± 8.7% in the CTR group, nonsignificant). In the CTR group, GH treatment induced an additional but not statistically significant decrease of 8.8% ± 12.4% in daily calories. Parenteral needs returned to near basal rates 6 months after GH discontinuation (GH: 77.6% ± 10.6% vs CTR: 73.2% ± 7.4%). Weight decreased slightly in both groups. No biological parameters varied significantly. Conclusions: GH did not improve the weaning off of PN in PN‐dependent children with SBS.     

Quantitative study of nerves of the human left atrium.

OBJECTIVES: To quantify and study the distribution of innervation of the left atrium and the pulmonary veins in humans. BACKGROUND: Damage to cardiac nerves has been hypothesized as the explanation for successful radiofrequency ablation of atrial fibrillation. METHODS: From January 2003 to September 2003, histologic and quantitative studies of innervation of the left atrium and the pulmonary veins was performed in 43 consecutive necropsied adult hearts (30 men and 3 women; mean age 45.5 +/- 12.4 years). The left atrium was sectioned in 1-cm slices from left to right, with the plane of section perpendicular to the long axis of the heart. Sections of the pulmonary veins at their ostia and sections 1 cm away of this structure also were obtained. Nerve fiber density was counted manually for each case and expressed as the mean number per slice. RESULTS: Numerous epicardial nerve fibers and ganglia having distinct patterns of distribution in the left atrium were found. Nerve density was significantly higher at the ostia of the four pulmonary veins than in their distal part (7.1 +/- 2.1 vs 5.2 +/- 1.3 for left upper pulmonary vein; 6.3 +/- 1.5 vs 5.2 +/- 1.7 for right upper pulmonary vein; 7.4 +/- 2 vs 5.9 +/- 2 for left lower pulmonary vein; 6.7 +/- 1.8 vs 3.9 +/- 1.3 for right lower pulmonary vein). The left superior vein was significantly more innervated than the right inferior vein (12.3 +/- 3 vs 10.6 +/- 1.4). Gradients of innervation were found from right to left (9.8 +/- 4.6 vs 18.5 +/- 6.6, P < .05) and from the front to the rear of the atrium (17.2 +/- 6.4 vs 20.7 +/- 6.5, P < .05). The same heterogeneous distribution was observed at the myocardial level but with thinner nerve fibers, making quantification difficult. Only very thin nerve fibers were present in the endocardium. CONCLUSIONS: The human left atrium exhibits several gradients of innervation at discrete sites. These findings may have clinical implications for radiofrequency ablation of atrial fibrillation.     

Shoshin béribéri: réémergence d’une pathologie ancienne ? à propos d’une série de 11 cas à Mayotte

In the French island of Mayotte in the Indian Ocean, the health and food situation remains contrasted. For a very long time dry beriberi women in postpartum had been suspected and treated. But in 2004 the first infantile epidemic of beriberi was scientifically authenticated and a program of thiaminic supplementation for the pregnant women and infants was set up. In this context, we describe an epidemic of 11 cases of shoshin beriberi among adults between January 2008 and Februar 2009. Over 11 cases of shoshin beriberi, 5 cases were confirmed biologically and 6 were probable. The sex ratio M/W was 0.37. The median age was 34 years. The clinic picture was typical: severe acute dyspnea, an agitation/drowsiness, right cardiac failure: polynevritis of the lower limbs was noted in 9 cases over 11. Biologically it was characterized by a lactic acidosis (average pH: 7.08, lactates: 12.08 mmol/l). The evolution was favorable in the 8 cases which could benefit from early thiaminic refill. The outbreak of an epidemic of shoshin beriberi among adults mainly in groups not having benefited from supplementation shows the effectiveness of the program but also its limits. We compare our series with others: the period from April to June when the food is less diversified, is confirmed as a higher risk period. The programs of nutritional education must be increased and a B1 vitamin supplementation for broader people during the rain season might be discussed.