Renal Denervation for Treatment of Cardiac Arrhythmias: State of the Art and Future Directions

Renal Denervation for Treatment of Cardiac Arrhythmias . It has now been more than a quarter of a century since modulation of the sympathetic nervous system was proposed for the treatment of cardiac arrhythmias of different origins. But it has also been some time since some of the early surgical attempts have been abandoned. With the development of ablation techniques, however, new approaches and targets have been recently introduced that have revolutionized our way of thinking about sympathetic modulation. Renal nerve ablation technology is now being successfully used for the treatment of resistant hypertension, but the indication spectrum might broaden and new therapeutic options might arise in the near future. This review focuses on the possible impact of renal sympathetic system modulation on cardiac arrhythmias, the current evidence supporting this approach, and the ongoing trials of this method in electrophysiological laboratories. We will discuss the potential roles that sympathetic modulation may play in the future.     

High-Risk Cutaneous Squamous Cell Carcinoma without Palpable Lymphadenopathy: Is There a Therapeutic Role for Elective Neck Dissection?

PURPOSE: The beneficial role of elective neck dissection (END) in the management of high-risk cutaneous squamous cell carcinoma (CSCC) of the head and neck remains unproven. Some surgical specialists suggest that END may be beneficial for patients with clinically node-negative (N0) high-risk CSCC, but there are few data to support this claim. We reviewed the available literature regarding the use of END in the management of both CSCC and head and neck SCC (HNSCC). METHODOLOGY: The available medical literature pertaining to END in both CSCC and HNSCC was reviewed using PubMed and Ovid Medline searches. RESULTS: Many surgical specialists recommend that END be routinely performed in patients with N0 HNSCC when the risk of occult metastases is estimated to exceed 20%; however, patients who undergo END have no proven survival benefit over those who are initially staged as N0 and undergo therapeutic neck dissection (TND) after the development of apparent regional disease. There is a lack of data regarding the proper management of regional nodal basins in patients with N0 CSCC. In the absence of evidence-based data, the cutaneous surgeon must rely on clinical judgment to guide the management of patients with N0 high-risk CSCC of the head and neck. CONCLUSIONS: Appropriate work-up for occult nodal disease may occasionally be warranted in patients with high-risk CSCC. END may play a role in only a very limited number of patients with high-risk CSCC.     

Sleep Problems in Two-Year-Olds

The parents of children aged between 18 and 32 months attendinga south-west London general practice were asked to completea questionnaire and diary about their child's sleep behaviour.Of the 142 parents approached, 116 (82%) responded and 99 completedboth the sleep diary and questionnaire. One-quarter of the respondentswere found to be troubled by their child's sleeping patterns.Analysis showed that the children of these parents had moredisturbed sleeping-waking rhythms, and slept less time bothduring the day and night compared with the children of parentswho had no complaints about the child's sleeping pattern. Nodemographic or social factors were found to be associated withdisturbed sleep patterns. However, children with sleep problemswere less often given an attachment object at bedtime, lessoften cuddled on waking at night and more often taken into theirparents' bed than other children. These findings raise the possibilitythat modification of the way parents handle the child with sleepproblems might effect an improvement in the child's sleep.     

Worksite health promotion programs in the United States: progress, lessons and challenges

Worksite health promotion programs have become increasinglyprevalent in the United States, and one or more health promotionprograms are found in two-thirds of all private worksites with50 or more employees. Reasons for recent growth in program frequencyinclude increased concern for worker health, rapidly escalatingemployer payments for health care benefits to workers, and growingevidence of a strong linkage between employee health and productivity.Published results of evaluations to date suggest that worksitehealth promotion programs can have positive impacts on healthbehaviors and health status. In addition, economic analysesare suggesting that some programs can affect the slope of healthcare costs and have the potential of high cost-effectivenesscompared to some clinical interventions. A number of researchchallenges remain, particularly understanding the influencesof the worksite environment and how employee health promotionprograms affect individual and organizational productivity.     

ABNORMAL CORNEAS MEASURED BY A NEW PHOTOGRAMMETRIC TECHNIQUE

The limitations of keratometry and photokeratoscopy are briefly discussed. A new photogrammetric technique of measuring corneal topography is described. Contours and cross-sections of abnormal corneas are presented to illustrate the scope and application of the new technique.     

Titration of Power Output During Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia

Radiofrequency lesions in the anterior, superior aspect of the tricuspid annulus result in selective elimination of fast pathway function in patients with typical atrioventricular (AV) nodal reentry tachycardia. This technique is simple and effective, but has been associated with a significant risk of inadvertent complete AV block. The purpose of this study was to compare the safety and effectiveness of two different techniques for radiofrequency catheter ablation of the fast AV nodal pathway. Initially, a fixed power output was used at each target site. This method was compared retrospectively to a newer technique where power output was gradually incremented at each site. Radiofrequency power was initially applied at 10 watts for 10–15 seconds. If no junctional ectopy or a change in PR intervoi was seen, power output was incremented by 2 to 4 watts every 10 to 15 seconds up to a maximum of 30 watts. Thirty seven of 38 (96%) patients treated using this incremental power output were cured of their AV nodal reentry tachycardia. None of these patients developed inadvertent complete AV block. In contrast, 92% of historic controls treated with a fixed power output between 20 and 30 watts achieved a primary success and nine of these 89 (10%) historic controls developed inadvertent complete AV block (P = 0.04). There was no difference in the amplitudes of atrial, His, or ventricular electrograms at the effective sites between the two groups. Conclusions: (1) the anterior approach to radiofrequency catheter ablation of typical AV nodal reentry is associated with a significant risk of inadvertent complete AV block if a fixed power output is used; (2) starting at low power and gradually incrementing the output during radiofrequency energy application reduces the risk of complete AV block; (3) this incremental technique does not compromise efficacy.     

Is There a Relationship Between a Mother's Mental State and Consulting the Doctor by the Family? A Study in a Military General Practice

A total of 174 families of service personnel with children between3 and 6 years of age were studied over a 6 month period. Allcontacts with the general practitioner, both in and out of hourstogether with the local casualty department were recorded. Mothersof the children were posted a specialty designed questionnaireto measure how seriously they perceived various childhood symptomsto be and a copy of the general health questionnaire, 28 questionversion (GHQ 28). The perceived severity questionnaire had beenpiloted previously in a neighbouring practice. The overall responserate was 77%. Analyses of the data showed that the factors mostsignificantly associated with a child's consultation frequencywere the psychological state of the mother, the mother's ownconsultation frequency and the number of children in the family;the last being an inverse relationship. No evidence was foundto suggest that the perception of the severity of illness variedwith the psychological state of the mother. In addition, thechildhood consultation rate was not influenced by the mother'sperception of the severity of childhood illness as measuredby the perceived severity questionnaire. Other factors suchas the age of the mother or child, within the age range studied,were not found to be significantly related to the child's frequencyof consulting. A mother's own consultation frequency was highlycorrelated with her GHQ 28 score, but more specifically withthe subsections that scored for depression and somatic symptoms.From the study, doctors who see children should seriously considerthe main reasons for a child's consultation. In particular,as mothers often make the decision as to whether their childshould see the doctor, the main patient may be the parent notthe child. Mothers who present themselves frequently may alsohave a high level of psychological distress.     

Interspecies Differences in the Phagocytic Activity of Pulmonary Macrophages Subjected to Acidic Challenge

Examining interspecies differences in response to ambient pollutantsis an essential component of risk assessment. The potentialhazard to public health from the inhalation of acid sulfateaerosols is of current concern. A significant biological targetis the pulmonary macrophage, which provides a primary defenseof the respiratory region of the lungs. One essential functionof these cells is phagocytosis of particles. This study assessedthe effects of acidic environments on the phagocytic activityof pulmonary macrophages obtained by lavage from humans andthree species of laboratory animals commonly used in acid aerosoltoxicology studies, namely, rats, rabbits, and guinea pigs.Cells were incubated with polystyrene latex particles in mediaacidified by addition of sulfuric acid. The percentage of cellswhich were phagocytic, as well as the relative number of particlesingested by these cells, was found to decrease with increasingacidity for all species. The ranking of response in order ofdecreasing sensitivity to acidic challenge was as follows: guineapig>rat>rabbit>human.