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I comment on a paper just appeared on JAFIB, aimed at providing an index quantifying the convenience of monitoring esophageal temperature during catheter ablation. The authors base their calculation on the data from four papers. I point out that the data from the two papers strongly against monitoring should be interpreted differently and I suggest how to retrieve more data for a more reliable determination of the said index. In addition, I briefly discuss the so-called antenna effect, sometimes put forward to discourage temperature monitoring. [ABSTRACT FROM AUTHOR]

Radiofrequency catheter ablation (RFCA) is an effective treatment for cardiac arrhythmias. Although generally safe, it is not completely exempt from the risk of complications. The great flexibility of computational models can be a major asset in optimizing interventional strategies if they can produce sufficiently precise estimations of the generated lesion for a given ablation protocol. This requires an accurate description of the catheter tip and the cardiac tissue. In particular, the deformation of the tissue under the catheter pressure during the ablation is an important aspect that is overlooked in the existing literature, which resorts to a sharp insertion of the catheter into an undeformed geometry. As the lesion size depends on the power dissipated in the tissue and the latter depends on the percentage of the electrode surface in contact with the tissue itself, the sharp insertion geometry has the tendency to overestimate the lesion obtained, which is a consequence of the tissue temperature rise overestimation. In this paper, we introduce a full 3D computational model that takes into account the tissue elasticity and is able to capture tissue deformation and realistic power dissipation in the tissue. Numerical results in FEniCS‐HPC are provided to validate the model against experimental data and to compare the lesions obtained with the new model and with the classical ones featuring a sharp electrode insertion in the tissue. [ABSTRACT FROM AUTHOR]

The original version of this paper contained an error: the Acknowledgements were dropped during early manuscript editing. [ABSTRACT FROM AUTHOR]

Objective: Radiofrequency (RF) cardiac ablation is a commonly used method for treating cardiac arrhythmias in which the information of the dynamic lesion heating is critical to cardiologists but is currently lacking. Electrical impedance tomography (EIT) is a temporal modality of imaging the changes in the electrical properties within a measured object and hence might be able to track the electrical variation due to temperature changes within the myocardium. Within this paper, (1) a time-efficient algorithm with self-weighted NOSER-prior and (2) a measurement filtering process for optimizing the number of measurement were proposed for monitoring the lesion size during the cardiac RF ablation, taking advantage of internal catheter-based electrodes and the prior information of anatomical structure and the catheter location, which are usually available during the ablation course. Approach: A tank model with a circular myocardium of 12 mm in thickness, 16 external electrodes on the boundary and three internal catheter-based electrodes positioned inside the endocardium were made. The ablations were simulated using Pennes’ bioheat transfer equation and the simulated temperature gradients were then transferred to EIT measurements. The algorithm used one reference ablation for its optimization and then was tested with numerous 90 s ablations containing three disturbances: the catheter location mapping, the wide range of varied myocardium conductivity and the blood’s cooling convection, and the Gaussian noises with 10–40 µV in standard deviation. Main results: The results showed that, with the optimized number of 55 measurements, the algorithm still performed well when dealing with all three disturbances plus the random noises up 25 µV. Specifically, the lesion depth and width were measured within 1.6 mm and 3.2 mm in error respectively in at least 80% out of 100 simulated ablations. Significance: The algorithm has successfully measured the lesion size with good accuracy and tolerances of noise and other system perturbations. More tests in vitro and in vivo are required in the future to confirm the algorithm’s feasibility. [ABSTRACT FROM AUTHOR]

The article comments on the paper "Ablation of posteroseptal and left posterior accessory pathways guided by left atrium-coronary sinus musculature activation sequence," by R. Pap and colleagues. According to the author, the paper reports an elegant technique to aid the localization and ablation of accessory pathways located near the cardiac septum. The author claims the technique utilizes the relative timing of electrograms recorded from the atrial and coronary sinus musculature.

A conference paper about comparative study of Radio-frequency ablation (RFA) vs. open surgery. Topics discussed include RFA that was associated with reduced general anesthesia; increased success rate for RFA; cost of open surgery which was less than RFA; increased use of intravenous sedation instead of general anesthesia.

The author reflects on the paper "Pacing or Ablation: Which is Better for Paroxysmal Atrial Fibrillation-Related Tachycardia-Bradycardia Syndrome?" by Y. Chen, R. Bai, T. Lin et al. within the issue. He suggests that Chen et al.'s research results are valid despite the limitations of the research. He argues that the research provides information on atrial fibrillation and will lead to increased professional discussion.

The article discusses the method for pharyngeal oxygen insufflation throughout paediatric and adult Macintosh laryngoscopy. It states that suction catheter is fixed to laryngoscope blade in angle between tongue and web using paper tape and the proximal end of catheter is connected to tubing of oxygen source. It cites that milelr blades can be used for pediatric patients. It also mentions that pharyngeal insufflation of oxygen shows delay onset of desaturation and hypoxemia during apnea.

An abstract of the conference paper "Interactive real-time mapping and ablation of the pulmonary veins and cavotricuspid isthmus in an ovine model with an externally-irrigated MRI-compatible ablation catheter," by Suchi Grover and colleagues is presented.

An abstract of the conference paper "Interactive real-time mapping and ablation of the pulmonary veins and cavotricuspid isthmus in an ovine model with an externally-irrigated MRIcompatible ablation catheter," by Anand N. Ganesan and colleagues is presented.

The article presents research papers from various journals related to medical topics in 2011. It mentions a study which shows the impact of a point of care test on the improvement of treatment rates for HIV infection. It cites another study which reveals the reduction of depression risks to coffee drinkers. It notes a research which determines the advantages for older adults who underwent percutaneous coronary intervention (PCI) to stay overnight in hospitals after the procedure. Meanwhile, an economic analysis discovers the potential of specialised foam mattresses to prevent pressure ulcers to people who lived in long term care homes.

A letter to the editor is presented in response to a paper by K. Van Boxem et al on the results of pulsed radiofrequency (PRF) for chronic intractable pain.

AN introduction to the journal is presented in which the editors discuss various papers published within the issue, including one on a comparison between intravenous sotalol and amiodarone for cardiac arrhythmias, one on atrial fibrillation (AF) and the risk of dementia/cognitive decline and another on a combined procedure of atrial fibrillation catheter ablation and percutaneous left atrial appendage occlusion in patients with AF.

A letter to the editor is presented in response to "Radiofrequency ablation of colorectal liver metastases: Long-term survival," a paper by D.T. Nielsen, S.M. Sørensen and F.V. Mortensen in the 2007 issue.

Complex fractionated atrial electrograms provide an important tool for identifying arrhythmogenic substrates that can be used to guide catheter ablation for atrial fibrillation (AF). However, fractionation is a phenomenon that remains unclear. This paper aims to evaluate the multifractal properties of electrograms in AF in order to propose a method based on multifractal analysis able to discriminate between different levels of fractionation. We introduce a new method, the h-fluctuation index (hFI), where h is the generalised Hurst exponent, to extract information from the shape of the multifractal spectrum. Two multifractal frameworks are evaluated: multifractal detrended fluctuation analysis and wavelet transform modulus maxima. hFI is exemplified through its application in synthetic signals, and it is evaluated in a database of electrograms labeled on the basis of four degrees of fractionation. We compare the performance of hFI with other indexes, and find that hFI outperforms them. The results of the study provide evidence that multifractal analysis is useful for studying fractionation phenomena in AF electrograms, and indicate that hFI can be proposed as a tool for grade fractionation associated with the detection of target sites for ablation in AF. [ABSTRACT FROM AUTHOR]

When it comes to the treatment of arrhythmias nowadays, antiarrhythmic drug therapy is not fully effective for the majority of cardiac arrhythmias, in terms of permanent suppression of the arrhythmia. In doing so, the use of these drugs is associated with a number of unpleasant and serious side effects. For this reason, the invasive treatment of arrhythmias by means of catheter radiofrequency (RF) ablation plays an increasing role in the treatment of tachycardia or heart rhythm disorders. There are many complications that appear during or after the procedure of catheter RF ablation. Complications are very rare and vary in different procedures. The overall incidence of periprocedural complications is as high as 3%. Complications appearing during the RF ablation can occur in any part of the procedure: as a result of insertion of peripheral sheaths, continuous sedations and anesthesia, exposure to radiation, insertion and manipulation of catheter electrodes in the blood vessels and heart cavity and applying RF energy. Generally, it has been proven that the complication rate decreases with experience of an ablation center, operator and the staff. Nurses have a significant role in the prevention and timely detection of complications. Nurses perform numerous and demanding procedures that greatly affect the course of the invasive procedure from the moment of the preparation of a patient in the ward to the periprocedural preparation and monitoring. Since this is a demanding procedure, standardization of the procedures and the application of customized protocols increase the quality of care and patient safety. This paper presents the experience of the Centre for arrhythmias of the University Hospital Centre "Sestre milosrdnice" and the results of the five-year follow-up of patients who underwent the RF catheter ablation. [ABSTRACT FROM AUTHOR]

Electrical impedance tomography is an attractive functional imaging method. It is currently limited in resolution and sensitivity due to the complexity of the inverse problem and the safety limits of introducing current. Recently, internal electrodes have been proposed for some clinical situations such as intensive care or RF ablation. This paper addresses the research question related to the benefit of one or more internal electrodes usage since these are invasive. Internal electrodes would be able to reduce the effect of insulating boundaries such as fat and bone and provide improved internal sensitivity. We found there was a measurable benefit with increased numbers of internal electrodes in saline tanks of a cylindrical and complex shape with up to two insulating boundary gel layers modeling fat and muscle. The internal electrodes provide increased sensitivity to internal changes, thereby increasing the amplitude response and improving resolution. However, they also present an additional challenge of increasing sensitivity to position and modeling errors. In comparison with previous work that used point sources for the internal electrodes, we found that it is important to use a detailed mesh of the internal electrodes with these voxels assigned to the conductivity of the internal electrode and its associated holder. A study of different internal electrode materials found that it is optimal to use a conductivity similar to the background. In the tank with a complex shape, the additional internal electrodes provided more robustness in a ventilation model of the lungs via air filled balloons. [ABSTRACT FROM AUTHOR]

The article presents a summary of the actions approved by the Board of Directors of the American Urological Association during the meeting held on May 2013 in San Diego, California including the development of a white paper by the Quality Improvement and Patient Safety Committee on catheter associated urinary tract infections, a policy statement on recertification and Maintenance of Certification, and a policy statement on the Early Detection of Prostate Cancer.

The last decade has seen dramatic advances in cardiac electrophysiology, particularly in its application for treatment of atrial fibrillation and other tachyarrhythmias. In this paper, the authors review key new technologies now beginning to impact on contemporary practice that are taking its therapeutic potential to new levels of efficacy and safety. [ABSTRACT FROM AUTHOR]

A response by D.T. Nielsen, S.M. Sørensen and F.V. Mortensen to a letter to the editor by Dr. López-Ben and Dr. Figueras concerning their paper "Radiofrequency ablation of colorectal liver metastases: Long-term survival?" is presented.