Plateau waveform shape allows a much higher patient shock energy tolerance in AF patients

Objectives: To evaluate the possible pain reduction of the plateau waveform in atrial fibrillation (AF) patients. Background: Previous studies have indicated that reduced amplitude waveforms would be less painful than a conventional (65/65% tilt) biphasic waveform. Computer modeling suggested that a moderately long (10–12 msec) plateau (flat topped) shock waveform would deliver equivalent effectiveness with the lowest possible peak amplitude. Methods: We enrolled 27 patients at two sites with persistent AF with a total of 220 shocks delivered during internal atrial cardioversion using an interleaved crossover design. Patient response was scored in three ways: (1) a verbally reported discomfort score, (2) visual analog scale (VAS), and (3) a blinded observer reporting a contraction score. Results: All scores were significantly reduced (P < 0.0001) by the plateau waveform with impressive statistics: Verbal discomfort (3.51 ± 0.13 to 2.89 ± 0.12), VAS (7.00 ± 0.56 to 5.91 ± 0.36), and contraction scores (1.94 ± 0.12 to 1.62 ± 0.12). The average pain threshold shift (TS) for the Verbal score was 2.34, while that for the VAS score was 2.30. (This means that the patient typically could tolerate 2.34 times as much energy with the plateau waveform for the same level of verbally reported discomfort.) The contraction TS was less at 1.57. Response scores were also corrected for the shock sequence number to control for the sensitization effect from multiple shocks. This increased the TS for the Verbal score to 3.58, but the shock number was not significant for the VAS. A pulmonary artery electrode return was associated with lower pain compared with a coronary sinus position. Conclusion: A plateau shaped biphasic waveform resulted in significantly increased shock energy pain tolerances. Controlling for session sensitization, patients tolerated over three times as much energy for the same verbally reported discomfort score.     

Transvenous cardioverter-defibrillator implantation in a patient with tricuspid mechanical prosthesis

Background . A 64-year-old woman was referred to our center because of poorly tolerated ventricular tachycardia (VT) at 210 bpm due to an old myocardial infarction. The patient had been operated on at age of 20 for mitral valve commissurolysis, at age of 49 for ductal carcinoma, at age of 56 for mitral valve replacement, and at age of 61 for tricuspid valve replacement. Left ventricular EF was 31%. The patient was in permanent atrial fibrillation (AF) since the age of 53. She had undergone three cardiac surgery procedures, ending with two prosthetic mechanical valves. The cardiac surgery team advised against an epicardial ICD implantation.
Results . We achieved a fully transvenous implant, with a screw-in defibrillation coil in the low right atrium and a bipolar pacing/sensing lead in a posterolateral branch of the coronary sinus. Pacing/sensing parameters were reliable, and effective defibrillation occurred at 20 J by a stepdown protocol. During 16-month follow-up, three VT episodes at 210 bpm were terminated by antitachycardia pacing (ATP) therapy. Left ventricular pacing/sensing was stable at long term.
Conclusion . Thanks to technologic improvements, transvenous ICD implantation is feasible and safe in patients with a tricuspid mechanical prosthesis.     

QT interval correction in patients with cirrhosis

Introduction: QT interval prolongation is a common electrophysiological abnormality in patients with cirrhosis. As QT interval varies with the heart rate, many QT correction formulas have been proposed, the Bazett's one being the most criticized because it overcorrects the QT interval and may be misleading. This study focused on the QT-RR relationship in patients with cirrhosis to derive a population-specific QT correction formula.
Methods: One hundred cirrhotic patients of different etiology and severity and 53 healthy controls comparable for age and sex were enrolled. The QT-RR relationship was analyzed in patients by five regression analysis models to derive the population-specific QT-RR equation. The QTc was calculated and compared with those calculated by four common QT correction formulas (Bazett, Fridericia, Framingham, and Hodges). The correlation coefficient QTc-RR was calculated as a measure of the independence of QTc from the original RR interval.
Results: In patients the QT-RR relationship was best described by the power equation "QT = 453.65 × RR^1/3.02" (R²= 0.41), similar to the Fridericia's formula. Bazett's formula led to the longest QTc (P < 0.0001), which was still significantly influenced by the RR interval (R =−0.39; P < 0.0001), while the estimated equation led to a QTc value not influenced by RR (R =−0.014).
Conclusion: Bazett's correction should be avoided in patients with cirrhosis because it still provides a rate-dependent QTc value and might be misleading, particularly when assessing the overall preoperative cardiac risk and the effect of drugs affecting the QT interval. In its place, our formula or that of Fridericia can be confidently employed.     

Virtual palpation of skeletal landmarks with multimodal display interfaces

The 3D location of skeletal landmarks on CT datasets is an important procedure, used in many research and clinical contexts. The standard procedure involves the segmentation of the CT images, the creation of a 3D surface bone model, and the location of the landmarks on this surface. However, the segmentation is time-consuming and requires skilled operators and sophisticated software. The aim of the present study is to evaluate the efficacy of a multimodal display interface to direct volumetric interactive visualization in performing a virtual palpation task. An expert operator used the CT dataset of a patient's thigh region to locate 14 femoral skeletal landmarks. This operation was repeatedly performed using different CT data representation; the accuracy and repeatability were compared to those achievable with the conventional procedure based on the segmented 3D surface. When a multimodal display interface (formed by an orthogonal slice, RXCT and interactive isosurface views) was used to perform the virtual palpation directly on the CT data, the average coordinates of the landmarks did not differ significantly from those located on the 3D surface, and the measurement repeatability was actually better with the multimodal display of the volumetric data than with the 3D surface. Thus, we can conclude that skeletal virtual palpation can be performed directly on the CT dataset, as far as the virtual palpation is performed with a multimodal display interface.     

Kleine-Levin syndrome: interface between neurology and psychiatry

We report the first episode of Kleine-Levin (KLS) syndrome in a 17-year-old male. The illness onset, clinical features, neuropsychological evaluation and polysomnographic recording are described. Typical symptoms hypersomnia, hyperphagia and sexual disinhibition were observed besides behavioral disturbances, polysomnographic and neuropsychological alterations. Behavioral disturbances similar to a manic episode including psychotic symptoms were relevant. The pharmacologic treatment included lithium, methylphenidate and risperidone. The introduction of risperidone aimed the control of psychotic symptoms and the persistent manifestations of hypersexuality after sleepiness control and to the best of our knowledge there are no other reports regarding risperidone use for KLS in the literature.     

Severe dysphagia in lower cranial nerve involvement as the initial symptom of Wegener's granulomatosis

We observed a 42-year-old woman presenting with severe dysphagia secondary to paralysis of the lower cranial nerves and right phrenic nerve involvement, followed by respiratory failure. An EMG confirmed bilateral denervation of the 9th, 10th, 11th and 12th cranial nerves and right phrenic nerve. Videolaryngoscopy showed bilateral vocal fold immobility. Anemia, elevated ESR, microhematuria and C-ANCA (PR-3) antibodies were detected. Brain MRI and CSF were normal. A chest CT showed bilateral, irregular pulmonary lesions. An 18F-FDG total body scan showed diffuse hypermetabolic regions in both pulmonary bases, in the mediastinic region and in the rhinopharynx, raising the suspicion of a neoplastic process. A transthoracic biopsy disclosed nodular granulomatous aggregates with multinucleated giant cells, supporting the diagnosis of Wegener's granulomatosis. Immunosuppressive therapy achieved complete clinical resolution and cleared the pulmonary lesions. To the best of our knowledge this is the first report of Wegener's granulomatosis presenting with neurogenic dysphagia due to lower cranial nerve palsy.     

Distribution of 26RFa binding sites and GPR103 mRNA in the central nervous system of the rat

The novel RFamide peptide 26RFa, the endogenous ligand of the orphan receptor GPR103, affects food intake, locomotion, and activity of the gonadotropic axis. However, little is known regarding the localization of 26RFa receptors. The present report provides the first detailed mapping of 26RFa binding sites and GPR103 mRNA in the rat central nervous system (CNS). 26RFa binding sites were widely distributed in the brain and spinal cord, whereas the expression of GPR103 mRNA was more discrete, notably in the midbrain, the pons, and the medulla oblongata, suggesting that 26RFa can bind to a receptor(s) other than GPR103. Competition experiments confirmed that 26RFa interacts with an RFamide peptide receptor distinct from GPR103 that may be NPFF2. High densities of 26RFa binding sites were observed in olfactory, hypothalamic, and brainstem nuclei involved in the control of feeding behavior, including the piriform cortex, the ventromedial and dorsomedial hypothalamic nuclei, the paraventricular nucleus, the arcuate nucleus, the lateral hypothalamic area, and the nucleus of the solitary tract. The preoptic and anterior hypothalamic areas were also enriched with 26RFa recognition sites, supporting a physiological role of the neuropeptide in the regulation of the gonadotropic axis. A high density of 26RFa binding sites was detected in regions of the CNS involved in the processing of pain, such as the dorsal horn of the spinal cord and the parafascicular thalamic nucleus. The wide distribution of 26RFa binding sites suggests that 26RFa has multiple functions in the CNS that are mediated by at least two distinct receptors.     

Woman, alcohol and environment: Emerging risks for health

Alcohol drinking is one of the most relevant problems in Western Countries but the negative effects of alcohol misuse are often neglected or underestimated with serious consequences for public health. Over the last few years a rapid growth in the number of drinking females and the decrease of their age of first use, have increased the health risk for women and their offspring. Moreover, modern environments facilitate pollutants exposure, further escalating the health risks due to lifestyle habits. This review takes into account the peculiarities of alcohol effects on female health and the risks of teratogenic effects. The possible interaction between alcohol and pollutants exposure is also discussed. The role of biomarkers against alcohol-related damage is presented as an invaluable clinical tool, including early intervention, treatment monitoring and, above all, prevention of prenatal non-reversible damage. Recent alcohol studies show the greater severity of alcohol damage in female subjects and the need of gender-targeted intervention.