Search

Contact forces play a significant role in the success of cardiac ablation. However, it is still challenging to estimate the applied contact force during the intervention when a catheter is under large bending or experiences multiple contact points along its body. A multi-element kinetostatic model of a tendon-driven catheter is proposed for real-time intrinsic force sensing. The model is able to accurately predict the steerable section shape of the catheter for given tendon tensions as well as the contact force at any known location on the steerable section. An algorithm is proposed which estimates the contact force on the steerable section using the model-based shape prediction in combination with end-position tracking of the steerable section. In this paper, undefined parameters and contact states of the force and shape estimation are defined and investigated. The shape prediction is validated in 3D space. The contact force estimation is validated with different catheter shpae, contraint catheter and buckling. It can be seen that end-position of the steerable section can be predicted with an accuracy of about 2.3 mm. In the validations, the 3-dimensional contact forces can be estimated accurately with an error of about 0.018 N and 1.6 ms computation time. Furthermore, the contact force estimation algorithm are able to incorporate external physical constraints along the catheter, which is validated in an experimental setup. [ABSTRACT FROM AUTHOR]

One method of removing malignant tissues from human organs is radiofrequency ablation. Thermal radiofrequency is a common technique of liver tumour therapy, which depends mainly on heating the infected region. This work proposes to investigate the thermal issue, which - in instance of excessive current - leads to extra lesion in liver tissues. However, the thermal lesions and the mistakes occurred in positioning the trocar instrument in the correct and accurate place arise the need to simulate and prediction of the thermal and electrical behaviour of the ablation operation. By using COMSOL multiphysics package, the process of hepatic tumour ablation has been simulated. Results show that by virtue of higher blood electrical conductivity, the nearby liver tissue around the electrode can be heated by rising its temperature due to electrical current from the radiofrequency probe according to the Joule law. Also, in this paper, different values of blood perfusion rate have been applied in the simulation process to investigate its effect on the ablation process. It is found that the increasing of mass flow rate of blood flow tends to bring down the fraction of necrotic tissue, which is contraindicated to the tumour ablation process. [ABSTRACT FROM AUTHOR]

Radiofrequency catheter ablation is one of the commonly available therapeutic methods for patients suffering from cardiac arrhythmias. The prerequisite of successful ablation is sufficient energy delivery at the target site. However, cardiac and respiratory motion, coupled with endocardial irregularities, can cause catheter drift and dispersion of the radiofrequency energy, thus prolonging procedure time, damaging adjacent tissue, and leading to electrical reconnection of temporarily ablated regions. Therefore, positional accuracy and stability of the catheter tip during energy delivery is of great importance for the outcome of the procedure. This paper presents an analytical scheme for assessing catheter tip stability, whereby a sequence of catheter tip motion recorded at sparse locations on the endocardium is decomposed. The spatial sliding component along the endocardial wall is extracted from the recording and maximal slippage and its associated probability are computed at each mapping point. Finally, a global map is generated, allowing the assessment of potential areas that are compromised by tip slippage. The proposed framework was applied to 40 retrospective studies of congenital heart disease patients and further validated on phantom data and simulations. The results show a good correlation with other intraoperative factors, such as catheter tip contact force amplitude and orientation, and with clinically documented anatomical areas of high catheter tip instability. [ABSTRACT FROM AUTHOR]

Most cardiac arrhythmias can be classified as atrial flutter, focal atrial tachycardia, or atrial fibrillation. They have been usually treated using drugs, but catheter ablation has proven more effective. This is an invasive method devised to destroy the heart tissue that disturbs correct heart rhythm. In order to accurately localise the focus of this disturbance, the acquisition and processing of atrial electrograms form the usual mapping technique. They can be single potentials, double potentials, or complex fractionated atrial electrogram (CFAE) potentials, and last ones are the most effective targets for ablation. The electrophysiological substrate is then localised by a suitable signal processing method. Sample Entropy is a statistic scarcely applied to electrograms but can arguably become a powerful tool to analyse these time series, supported by its results in other similar biomedical applications. However, the lack of an analysis of its dependence on the perturbations usually found in electrogram data, such as missing samples or spikes, is even more marked. This paper applied SampEn to the segmentation between non-CFAE and CFAE records and assessed its class segmentation power loss at different levels of these perturbations. The results confirmed that SampEn was able to significantly distinguish between non-CFAE and CFAE records, even under very unfavourable conditions, such as 50% of missing data or 10% of spikes. [ABSTRACT FROM AUTHOR]

Radiofrequency ablation (RFA) is currently one of the most effective methods for minimally invasive treatment of hepatic tumors. Planning the probe placements is an essential and challenging step in RFA treatment. To completely destroy the tumor with minimum amount of affected native tissue, a new RFA planning system is proposed in this paper. In the proposed planning system, the minimum number of ablations and a conical insertion region for each ablation session are determined automatically. Based on the geometric character of the tumor, a novel clustering algorithm is developed to allow a better layout of the overlapping ablations. For each case, we force the clustering process under the constraint of a manually defined puncture scope, such that all of the needle trajectories are gathered in a reasonable region. Moreover, the proposed planning system enables the clinician to manually choose a proper insertion path inside the conical insertion region to avoid penetrating large vessels or ribs, which is critical in RFA treatment. The proposed planning system was evaluated on 18 CT scan images and two clinical cases. Results implied that the planning system could provide feasible and accurate RFA treatment plans for hepatic tumors. [ABSTRACT FROM PUBLISHER]

Radio frequency (RF) ablation of the myocardium is used to treat various cardiac arrhythmias. The size, spacing, and transmurality of lesions have been shown to affect the success of the ablation procedure; however, there is currently no method to directly image the size and formation of ablation lesions in real time. Intracardiac myocardial elastography (ME) has been previously used to image the decrease in cardiac strain during systole in the ablated region as a result of the lesion formation. However, the feasibility of imaging multiple lesions and identifying the presence of gaps between lesions has not yet been investigated. In this paper, RF ablation lesions ( $n = 7$ ) were generated in the left ventricular epicardium in three anesthetized canines. Two sets of two lesions each were created in close proximity to one another with small gaps (1.5 and 4 cm), while one set of two lesions was created directly next to each other with no gap. A clinical intracardiac echocardiography system was programmed to transmit a custom diverging beam sequence at 600 Hz and used to image the ablation site before and after the induction of ablation lesions. Cumulative strains were estimated over systole using a normalized cross-correlational displacement algorithm and a least-squares strain kernel. Afterward, lesions were excised and subjected to tetrazolium chloride staining. Results indicate that intracardiac ME was capable of imaging the reduction in systolic strain associated with the formation of an ablation lesion. Furthermore, lesion sets containing gaps were able to be distinguished from lesion sets created with no gaps. These results indicate that the end-systolic strain measured using intracardiac ME may be used to image the formation of lesions induced during an RF ablation procedure, in order to provide critical assessment of lesion viability during the interventional procedure. [ABSTRACT FROM PUBLISHER]

In contrast to ventricular tachycardia (VT) that occurs in the setting of a structurally normal heart, VT that occurs in patients with structural heart disease carries an elevated risk for sudden cardiac death (SCD), and implantable cardioverter-defibrillators (ICDs) are the mainstay of therapy. In these individuals, catheter ablation may be used as adjunctive therapy to treat or prevent repetitive ICD therapies when antiarrhythmic drugs are ineffective or not desired. However, certain patients with frequent premature ventricular contractions (PVCs) or VT and tachycardiomyopathy should be considered for ablation before ICD implantation because left ventricular function may improve, consequently decreasing the risk of SCD and obviating the need for an ICD. The goal of this paper is to review the pathophysiology, mechanism, and management of VT in the setting of structural heart disease and discuss the evolving role of catheter ablation in decreasing ventricular arrhythmia recurrence. [ABSTRACT FROM AUTHOR]

Multi-modality cardiac imaging plays a key role in the management of patients with cardiovascular diseases. It allows a combination of complementary anatomical, morphological and functional information, increases diagnosis accuracy, and improves the efficacy of cardiovascular interventions and clinical outcomes. Fully-automated processing and quantitative analysis of multi-modality cardiac images could have a direct impact on clinical research and evidence-based patient management. However, these require overcoming significant challenges including inter-modality misalignment and finding optimal methods to integrate information from different modalities. This paper aims to provide a comprehensive review of multi-modality imaging in cardiology, the computing methods, the validation strategies, the related clinical workflows and future perspectives. For the computing methodologies, we have a favored focus on the three tasks, i.e., registration, fusion and segmentation, which generally involve multi-modality imaging data, either combining information from different modalities or transferring information across modalities. The review highlights that multi-modality cardiac imaging data has the potential of wide applicability in the clinic, such as trans-aortic valve implantation guidance, myocardial viability assessment, and catheter ablation therapy and its patient selection. Nevertheless, many challenges remain unsolved, such as missing modality, modality selection, combination of imaging and non-imaging data, and uniform analysis and representation of different modalities. There is also work to do in defining how the well-developed techniques fit in clinical workflows and how much additional and relevant information they introduce. These problems are likely to continue to be an active field of research and the questions to be answered in the future. [Display omitted] • Provide a systematic review of multi-modality cardiac image computing. • Summarize methodologies of cardiac image registration, fusion, and segmentation. • Discuss challenges and future directions of multi-modality cardiac image computing. [ABSTRACT FROM AUTHOR]

The article discusses a paper by S. Avazzabeh and colleagues on the effect of electroporation on cardiac-associated cell types during cardiac ablation. Topics mentioned include a description of different kinds of cell culture for electroporation, the typical protocol of irreversible electroporation, the presence of pycnotic type morphology in both neurons and cardiomyocytes, and the influence of different inter-pulse intervals.

The article discusses a paper by R. C. Pimentel and colleagues on whether intracardiac echocardiography (ICE) can reduce the complications of atrial fibrillation ablation. Topics mentioned the advantages and disadvantages of ICE, the consequences of the inability of ICE to visualize thrombus and the aortic root, and the association of ICE use with rates of in-hospital mortality and length of stay.

The article comments on a research paper by J. Aguilera and colleagues on the recurrence of arrhythmia experienced by patients with atrial fibrillation (AF) and chronically isolated pulmonary veins (CI PV). Topics mentioned include the advantage of extensive ablation in achieving rhythm control, the association of nonparoxysmal AF transformation to paroxysmal AF with outcome of a limited repeat ablation method, and the arrhytmia-free survival of patients with CI PV.

Purpose: One important challenge in image-guided ablative therapies is the effect of heat diffusion which can cause damage to surrounding organs and limit the ability to achieve a conformal pattern of thermal damage. Furthermore, tissue properties such as perfusion and energy absorption can be dynamic and difficult to measure. This paper attempts to address these problems by proposing new control methods. Materials and methods: A novel predictive approach was developed to compensate for the effect of heat diffusion using a minimally invasive rotating ultrasound heating applicator for ablative therapy. This method can be merged into any closed-loop control strategy. A binary controller, a previously developed adaptive proportional-integral controller, and a model reference adaptive controller were employed and compared, all with the predictive element incorporated. The reason for choosing these controllers was that none of them needed a model of the tissue or exact values of their parameters. Results: The effectiveness of these controllers was demonstrated through both simulation and experimental studies. The results were consistent and demonstrated equivalent performance between controllers. Conclusions: The dominant influence on radial targeting accuracy was the prediction element described in this paper. A binary controller with a predictive element may provide the best balance of performance and simplicity for this application. [ABSTRACT FROM AUTHOR]

There are emerging epidemics of atrial fibrillation (AF) and heart failure in most developed countries, with a significant health burden. Due to many shared pathophysiological mechanisms, which facilitate the maintenance of each condition, AF and heart failure co-exist in up to 30% of patients. In the circumstance where known structural causes of heart failure (such as myocardial infarction) are absent, patients presenting with both conditions present a unique challenge, particularly as the temporal relationship of each condition can often remain elusive from the clinical history. The question of whether the AF is driving, or significantly contributing to the left ventricular (LV) dysfunction, rather than merely a consequence of heart failure, has become ever more pertinent, especially as catheter ablation now offers a significant advancement over existing rhythm control strategies. This paper will review the inter-related physiological drivers of AF and heart failure before considering the implications from the outcomes of recent clinical trials in patients with AF and heart failure. [ABSTRACT FROM AUTHOR]

The paper presents the design of a medical instrument proposed for the robotic assisted radio frequency ablation procedure using the PARABRACHYROB parallel robotic system. Following the medical procedure requirements, a protocol is established for the robotic assisted radiofrequency liver ablation to serve as design considerations for the medical instrument. The design of the experimental model and its integration on PARA-BRACHYROB are presented. [ABSTRACT FROM AUTHOR]

Radio-frequency ablation (RFA) is used to locally disrupt electrical propagation in myocardium and treat arrhythmias, and direct visualization of ablation lesions by acoustic radiation force methods may benefit RFA procedures. This paper compares four imaging modalities, B-mode, acoustic radiation force impulse (ARFI), single-track-location shear wave elasticity imaging (STL-SWEI), and multiple-track-location shear wave elasticity imaging (MTL-SWEI), in their ability to resolve RFA lesions in four ex vivo experiments. Ablation lesions are shown to be marked by at least a local halving of ARFI displacements and doubling of shear wave speeds. In a controlled ablation of ex vivo porcine and canine cardiac tissue, STL-SWEI and ARFI are shown to have a similar CNR, better than MTL-SWEI and B-mode. The SWEI modalities are demonstrated to have improved imaging of distal lesion boundaries. Gaps smaller than 5 mm are visualized in ablation lines made of discretely spaced ablations, and complex structures are reconstructed through depth in an “x” ablation experiment. Scans of suspended atria show increased noise, but successfully visualize ablations in ARFI, MTL-SWEI, and STL-SWEI. [ABSTRACT FROM PUBLISHER]

Goal: In this paper, we used in silico patient-specific models constructed from three-dimensional delayed-enhanced magnetic resonance imaging (DE-MRI) to simulate intracardiac electrograms (EGM). These included electrically abnormal EGM as these are potential radiofrequency ablation (RFA) targets. Methods: We generated signals with distinguishable macroscopic normal and abnormal characteristics by constructing MRI-based patient-specific structural heart models and by solving the simplified biophysical Mitchell–Schaeffer model of cardiac electrophysiology (EP). Then, we simulated intracardiac EGM by modeling a recording catheter using a dipole approach. Results: Qualitative results show that simulated EGM resemble clinical signals. Additionally, the quantitative assessment of signal features extracted from the simulated EGM showed statistically significant differences (p $<$ 0.0001) between the distributions of normal and abnormal EGM, similarly to what is observed on clinical data. Conclusion: We demonstrate the feasibility of coupling simplified cardiac EP models with imaging data to generate intracardiac EMG. Significance: These results are a step forward in the direction of the preoperative and noninvasive identification of ablation targets to guide RFA therapy. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) as one kind of arrhythmias has gained the most attention clinically and the greatest progress in evidence-based medicine at present. Besides the therapies such as anticoagulant therapy and ventricular rate control, catheter ablation (energy sources including radiofrequency and freezing) is the first choice of treatment recommended by guidelines at present from the perspective of symptom control. However, its effectiveness in preventing against cardiac apoplexy has not been authorized yet. The technique of percutaneous left atrial appendage occlusion fills the blank and becomes one of the better choices for AF patients who are high-risky of stroke and intolerance of permanent anticoagulant therapy. TTie derivative "one-stop treatment of AF thereof has become one of hot topics of current industry. This paper discusses the methcxlology of the "one-stop treatment of AF and advances of its curative effect. [ABSTRACT FROM AUTHOR]

Cardiologists & Partners is a physicians group initiated and established by domestic authoritative experts in the field of cardiovascular medicine. By integrating and allocating the advanced medical technologies and top-quality human resources of first class hospitals, it aims to help primary medical institutions of county level in personnel training and technical assistance. In order to make a detailed introduction to this innovative exploration in the field of cardiovascular medicine, and promote understanding of physicians group among more cardiovascular specialists, this paper focuses on the exploration and practice of physicians group from several aspects involving the epidemiology of ventricular arrhythmias, current situation of Cardiologists & Partners, its efforts in helping county hospitals, its pre-discharge management, in-hospital appliance therapy and post-discharge management, clinical research data management, future development directions, etc. [ABSTRACT FROM AUTHOR]

Ventricular arrhythmia originating from the coronary venous system (CVS) is not rare in clinical practice. However, the success rate of catheter ablation is low due to the complicated anatomical structure of CVS and its adjacent tissue. This paper reviews on the anatomical structure of CVS and its adjacent tissue, and the ECG features and catheter ablation of ventricular arrhythmia, aiming to elevate the success rate of catheter ablation of ventricular arrhythmia originating from this site. [ABSTRACT FROM AUTHOR]

Background:Radiofrequency ablation (RFA) and percutaneous ethanol injection (PEI) are important treatments for patients with hepatocellular carcinoma (HCC) who are not eligible for resection and liver transplantation. Therefore, it is important to establish comparisons between RFA, PEI and the two therapies in combination. Aims:To evaluate the clinical efficacy and safety of combined RFA-PEI versus monotherapy with either RFA or PEI for HCC to provide references for clinical practice and further research. Methods:We searched all eligible studies published before September 2015 in the Cochrane Library, PubMed, Embase, Web of Science and Chinese databases, such as CBM, CNKI, VIP and WanFang and also retrieved papers from other sources. All relevant controlled trials were collected. Meta-analyses were performed using RevMan version 5.3 software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). Results:Thirteen trials with 1621 patients were identified. Compared with PEI, RFA was associated with significant improvement in overall survival (OS) rate at 1, 2, 3 and 4 years, cancer-free survival (CFS) rate at 1, 2 and 3 years and complete tumour necrosis. RFA was associated with a significant reduction in the local recurrence rate at 1, 2 and 3 years. However, RFA was also associated with a higher total risk of complications. Compared with RFA alone, combined RFA-PEI was associated with a significant improvement in the OS rate at 1.5, 2 and 3 years and a significant reduction in the local recurrence rate. However, combined RFA-PEI was also associated with a higher risk of fever. Conclusion:The combination of RFA and PEI appears to be the optimal treatment strategy when considering combined RFA-PEI or either RFA or PEI alone. Combined RFA-PEI significantly improves OS and reduces the risk of local recurrence without increasing major complications. Further large-scale studies are needed to assess economic outcomes and quality of life. [ABSTRACT FROM AUTHOR]

Background and Objective Optimal targets for persistent atrial fibrillation (persAF) ablation are still debated. Atrial regions hosting high dominant frequency (HDF) are believed to participate in the initiation and maintenance of persAF and hence are potential targets for ablation, while rotor ablation has shown promising initial results. Currently, no commercially available system offers the capability to automatically identify both these phenomena. This paper describes an integrated 3D software platform combining the mapping of both frequency spectrum and phase from atrial electrograms (AEGs) to help guide persAF ablation in clinical cardiac electrophysiological studies. Methods 30 s of 2048 non-contact AEGs (EnSite Array, St. Jude Medical) were collected and analyzed per patient. After QRST removal, the AEGs were divided into 4 s windows with a 50% overlap. Fast Fourier transform was used for DF identification. HDF areas were identified as the maximum DF to 0.25 Hz below that, and their centers of gravity (CGs) were used to track their spatiotemporal movement. Spectral organization measurements were estimated. Hilbert transform was used to calculate instantaneous phase. Results The system was successfully used to guide catheter ablation for 10 persAF patients. The mean processing time was 10.4 ± 1.5 min, which is adequate comparing to the normal electrophysiological (EP) procedure time (120∼180 min). Conclusions A customized software platform capable of measuring different forms of spatiotemporal AEG analysis was implemented and used in clinical environment to guide persAF ablation. The modular nature of the platform will help electrophysiological studies in understanding of the underlying AF mechanisms. [ABSTRACT FROM AUTHOR]

Radiofrequency ablation (RFA) is hindered when tissue temperature reaches 100 °C. At this temperature, tissue vaporization occurs, which prevents electrical currents from flowing into the tissue. Smaller lesions are created as a result. One way to overcome this is to infuse saline into the tissue prior to RFA. Saline can increase the electrical conductivity of the surrounding tissue due to the abundance of ions inside the solution. This permits a greater distribution of electrical currents that can lead to larger lesion sizes. Although this procedure has been shown to produce larger lesions, the technique is risky due to the potential for the saline to extravasate into healthy regions of the tissue; hence, leading to unnecessary ablation. A computational model is developed in this paper to predict the formation of lesion following saline-infused RFA. The model incorporates the transport of saline inside the tissue, the resistive heating during ablation and the formation of lesion through cell death modeling. Results show that there is an optimal infusion volume that leads to the largest increase in the lesion size. With further developments, the model may be used for the planning of saline-infused RFA treatment. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this paper is to present an outcome validation tool for tumor radiofrequency (RF) ablation and resection. Methods: Intervention assessment tools require an accurate registration of both pre- and postoperative computed tomographies able to handle big deformations. Therefore, a physics-based method is proposed with that purpose. To increase the accuracy both automatically detected internal and surface physical landmarks are incorporated in the registration process. Results: The algorithm has been evaluated in 25 clinical datasets containing RF ablations, resections, and patients with recurrent tumors. The achieved accuracy is 1.2 mm measured as mean internal distance between vessel landmarks and a positive predictive value of 0.95. The quantitative and qualitative results of the outcome validation tool show that in 50% of the cases tumors were only partially covered by the treatment. Conclusion: The use of internal and surface landmarks combined with a physics-based registration method increases the accuracy of the results compared to the accuracy of state of the art methods. An accurate outcome validation tool is important in order to certify that the tumor and its safety margin were fully covered by the treatment. Significance: An accurate outcome validation tool can result in a decrease of the tumor recurrence rate. [ABSTRACT FROM AUTHOR]

Atrial fibrillation ( AF) is a kind of clinically common arrhythmia ' which can be divided into symptomatic and asymptomatic AF. Monitoring instruments for arrhythmia is various ' which can be classified into external monitor and cardiac implantable devices. Despite being applied in diagnosing AF and its type，cardiac implantable devices can also be utilized in guiding the treatment of AF-induced stroke and accurately evaluating the recurrence rate of AF after catheter ablation. This paper reviews on the above issues. [ABSTRACT FROM AUTHOR]

Barrett’s esophagus is a condition in which the normal squamous lining of the esophagus has been replaced by columnar epithelium containing intestinal metaplasia induced by recurrent mucosal injury related to gastroesophageal reflux disease. Barrett’s esophagus is a premalignant condition that can progress through a dysplasia-carcinoma sequence to esophageal adenocarcinoma. Multiple endoscopic ablative techniques have been developed with the goal of eradicating Barrett’s esophagus and preventing neoplastic progression to esophageal adenocarcinoma. For patients with high-grade dysplasia or intramucosal neoplasia, radiofrequency ablation with or without endoscopic resection for visible lesions is currently the most effective and safe treatment available. Recent data demonstrate that, in patients with Barrett’s esophagus and low-grade dysplasia confirmed by a second pathologist, ablative therapy results in a statistically significant reduction in progression to high-grade dysplasia and esophageal adenocarcinoma. Treatment of dysplastic Barrett’s esophagus with radiofrequency ablation results in complete eradication of both dysplasia and of intestinal metaplasia in a high proportion of patients with a low incidence of adverse events. A high proportion of treated patients maintain the neosquamous epithelium after successful treatment without recurrence of intestinal metaplasia. Following successful endoscopic treatment, endoscopic surveillance should be continued to detect any recurrent intestinal metaplasia and/or dysplasia. This paper reviews all relevant publications on the endoscopic management of Barrett’s esophagus using radiofrequency ablation. [ABSTRACT FROM AUTHOR]

Chronic musculoskeletal pain ( CMP) is a significant burden for chronic pain sufferers, their medical and allied health treatment providers, and the U. S. medical system. The U. S. military has seen a significant increase in CMP with increased injuries stemming from military operations in Iraq and Afghanistan, and advances in care for CMP are sorely needed. Poor chronic pain treatment in the military has led to high levels of costly health care utilization with related costs estimated in billions of dollars. The functional occupational restoration treatment ( FORT) trial, funded by the Congressionally Directed Medical Research Programs (Department of Defense), was the first formal, randomized trial of a novel interdisciplinary management program for CMP among active duty service members. Excellent clinical outcomes at posttreatment and long-term follow-up have been reported elsewhere. This paper examined patterns of health care utilization among FORT study participants for a period of 1 year before and after the study intervention or yoked, 3-week control period. We examined the military's Armed Forces Health Longitudinal Technology Application, which went online in 2004, to identify costly health visits and procedures consumed by study completers. We then compared utilization rates between those who received the interdisciplinary FORT treatment and those who were randomized to treatment as usual. Our analyses revealed significant between-group differences at posttreatment (controlling for pretreatment intervention use), with FORT participants receiving significantly fewer procedures including emergency department intervention, injections, and radio frequency nerve ablations. This paper precedes a follow-up study of mediating factors for health care utilization after interdisciplinary treatment. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To evaluate the current status of focal therapy as the salvage treatment option for patients with recurrent prostate cancer after established therapy (radiation, surgery) failure for localized tumor. METHODS: A MedLine search using specified search terms was done on December 23, 2011. This research rendered 346 papers related to High-Intensity Focused Ultrasound (HIFU), 644 papers related to cryosurgery, 180 related to photodynamic therapy and 3 articles related to radio frequency ablation. Very few of these papers presented original outcome data and are included in the present review. RESULTS: No controlled trial was available for analysis. CONCLUSIONS: Salvage HIFU in patients with local recurrence of prostate cancer after radical EBRT indicate is a reasonable treatment option, but better patient selection criteria are needed. It is a promising treatment option for local recurrence after radiation therapy, with morbidity comparable with other forms of salvage treatment. The side effects are not negligible but comparable with other forms of salvage treatment. Photodynamic therapy is a new option that could be suitable for organ-confined PC recurrence after radiotherapy, but the data are very few. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The purpose of this paper is to explore the feasibility of developing a MRI-compatible needle driver system for radiofrequency ablation (RFA) of breast tumors under continuous MRI imaging while being teleoperated by a haptic feedback device from outside the scanning room. The developed needle driver prototype was designed and tested for both tumor targeting capability as well as RFA. Methods: The single degree-of-freedom (DOF) prototype was interfaced with a PHANToM haptic device controlled from outside the scanning room. Experiments were performed to demonstrate MRI-compatibility and position control accuracy with hydraulic actuation, along with an experiment to determine the PHANToM’s ability to guide the RFA tool to a tumor nodule within a phantom breast tissue model while continuously imaging within the MRI and receiving force feedback from the RFA tool. Results: Hydraulic actuation is shown to be a feasible actuation technique for operation in an MRI environment. The design is MRI-compatible in all aspects except for force sensing in the directions perpendicular to the direction of motion. Experiments confirm that the user is able to detect healthy vs. cancerous tissue in a phantom model when provided with both visual (imaging) feedback and haptic feedback. Conclusion: The teleoperated 1-DOF needle driver system presented in this paper demonstrates the feasibility of implementing a MRI-compatible robot for RFA of breast tumors with haptic feedback capability. [Copyright &y& Elsevier]

• A numerical model was used to simulate ultrasound intervention ablation device. • Low-intensity ultrasound induced pressure field in pulmonary vein was simulated. • Low-intensity ultrasound induced temperature field in pulmonary vein was simulated. • Thermal damage in the vein was analyzed based on equivalent heat dose equation. Atrial fibrillation (AF) is currently the most common arrhythmia disease in clinic and its incidence increases with the age, which seriously endangers peoples health. Percutaneous catheter ablation is an important treatment strategy for AF, and pulmonary vein (PV) isolation has been widely accepted as the key approach of AF ablation since AFs are regarded the most important trigger of AF. The ablation scheme based on low-intensity ultrasound has the advantages of low biotoxicity and minimal invasion, while its applicability and parameter settings are still not well known. In this paper, we proposed a finite element model that could be used to simulate the ablation application of ultrasound intervention device for the purpose of PV isolation. The acoustic pressure and temperature fields generated during the process of low-intensity ultrasound pulmonary vein ablation were simulated based on linear acoustic wave equation and Pennes biological heat transfer equation, and then the corresponding thermal damage was quantitatively analyzed by taking into account of the equivalent heat dose equation. The results showed that the incident acoustic energy was mainly concentrated in the blood vessels of PV, and the temperature rise was mainly constrained in the inner part of the vessel walls, which suggested that high temperature rise could be realized nearby the central region of the low-intensity ultrasound transducer to achieve significant thermal damage in the inner part of the vessel walls. Moreover, the current study also discussed the impacts of different parameters on the ultrasound ablation effect, which would provide theoretical support and guidance for the optimization of ultrasound ablation strategy in clinics. [ABSTRACT FROM AUTHOR]

A challenging problem of radiofrequency ablation (RFA) in liver surgery is to accurately estimate the shapes and sizes of RFA lesions whose formation depends on intrinsic variations of the thermal–electrical properties of soft tissue. Large tumors, which can be as long as 10 cm or more, further complicate the problem. In this paper, a probabilistic bio-heating finite element (FE) model is proposed and developed to predict RFA lesions. Uncertainties of RFA lesions are caused by the probabilistic nature of five thermal–electrical liver properties: thermal conductivity, liver tissue density, specific heat, blood perfusion rate and electrical conductivity. Confidence levels of shapes and sizes of lesions are generated by the FE model incorporated with the mean-value first-order second-moment (MVFOSM) method. Based on the probabilistic FE method, a workflow of RFA planning is introduced to enable clinicians to preoperatively view the predicted RFA lesions in three-dimension (3D) within a hepatic environment. Accurate planning of the RFA needle placements can then be achieved based on the interactive simulation and confidence level selection. [ABSTRACT FROM AUTHOR]

Rhythm control of atrial fibrillation (AF) remains challenging, with modest long-term success rates. Atrial fibrosis has been associated with AF, but the clinical utility of assessment of this fibrosis has yet to be fully elucidated. In this paper we review the current state of understanding of the pathophysiology of atrial fibrosis in AF, and its impact upon the instigation and propagation of the arrhythmia. Fibrosis causes an increase in volume of dysfunctional extracellular matrix, and is associated with cellular alterations such as hypertrophy, apoptosis and membrane dysfunction within the atrial myocardium. In turn, these cause pathological alterations to atrial conduction, such as increased anisotropy, conduction block and re-entry, which can lead to AF. We review current methods of assessing atrial fibrosis and their impact upon the prediction of success of interventional rhythm control strategies such as ablation and cardioversion. We focus particularly on circulating biomarkers of fibrosis and scar formation; their role in the fibrotic process, and their value in the prediction of rhythm control success. We also review imaging and invasive electrocardiographic mapping techniques that may identify fibrosis, and again assess their potential predictive value. In this area there exist many unanswered questions, but further work will help to refine techniques to reliably identify and treat those patients who are most likely to benefit from rhythm control treatment strategies. [ABSTRACT FROM AUTHOR]

Integration of electrical and structural information for scar characterization in the left ventricle (LV) is a crucial step to better guide radio-frequency ablation therapies, which are usually performed in complex ventricular tachycardia (VT) cases. This integration requires finding a common representation where to map the electrical information from the electro-anatomical map (EAM) surfaces and tissue viability information from delay-enhancement magnetic resonance images (DE-MRI). However, the development of a consistent integration method is still an open problem due to the lack of a proper evaluation framework to assess its accuracy. In this paper we present both: (i) an evaluation framework to assess the accuracy of EAM and imaging integration strategies with simulated EAM data and a set of global and local measures; and (ii) a new integration methodology based on a planar disk representation where the LV surface meshes are quasi-conformally mapped (QCM) by flattening, allowing for simultaneous visualization and joint analysis of the multi-modal data. The developed evaluation framework was applied to estimate the accuracy of the QCM-based integration strategy on a benchmark dataset of 128 synthetically generated ground-truth cases presenting different scar configurations and EAM characteristics. The obtained results demonstrate a significant reduction in global overlap errors (50–100%) with respect to state-of-the-art integration techniques, also better preserving the local topology of small structures such as conduction channels in scars. Data from seventeen VT patients were also used to study the feasibility of the QCM technique in a clinical setting, consistently outperforming the alternative integration techniques in the presence of sparse and noisy clinical data. The proposed evaluation framework has allowed a rigorous comparison of different EAM and imaging data integration strategies, providing useful information to better guide clinical practice in complex cardiac interventions. [ABSTRACT FROM AUTHOR]

Very frequent premature ventricular complexes (PVCs) may be a reversible cause of dilated cardiomyopathy. Literature on this largely unrecognized entity has increased in the last 15 years. This paper reviews the literature on the consequences of frequent PVCs on myocardial function and management of PVC-associated cardiomyopathy. The authors reviewed articles published in English before June 2015 describing pathophysiology, risk factors, symptoms, time course, treatment, and outcome of cardiomyopathy associated with PVCs. The search was conducted using Medline and Embase. Keywords included: cardiomyopathy, catheter ablation, antiarrhythmic drug (AAD), pathophysiology, and ventricular premature contractions or synonyms. PVC-associated cardiomyopathy is associated with a high burden of PVC (over 20% of heartbeats). Other risk factors include electrophysiological characteristics, such as PVC QRS width, presence of ventricular tachycardia, retrograde P waves, interpolation, polymorphic PVCs, and longer coupling intervals. Symptoms include palpitations, light-headedness, dyspnea, cough, and dysphagia. The systolic dysfunction and chamber dilatation progress over a few years. Once the PVCs are suppressed by radiofrequency ablation or AADs, the cardiomyopathy usually resolves within 6 months. The pathophysiology remains unknown, but hypotheses mainly include ventricular dyssynchrony resulting in hemodynamic disturbances and abnormalities in calcium handling and oxygen consumption. PVC-associated cardiomyopathy remains a largely unrecognized entity. It is a reversible cause of dilated cardiomyopathy that results from abnormal calcium and oxygen handling within the myocyte, dyssynchrony, and hemodynamic compromise from inefficient heartbeats. Suppression of the PVCs improves myocardial function, cardiac chamber sizes, and patient's symptoms. [ABSTRACT FROM AUTHOR]

This paper presents a method to characterize tissue thermal damage by taking into account the thermal-mechanical effect of soft tissues for thermal ablation. This method integrates the bio-heating conduction and non-rigid motion dynamics to describe thermal-mechanical behaviors of soft tissues and further extends the traditional tissue damage model to characterize thermal-mechanical damage of soft tissues. Simulations and comparison analysis demonstrate that the proposed method can effectively predict tissue thermal damage and it also provides reliable guidelines for control of the thermal ablation procedure. [ABSTRACT FROM AUTHOR]

This paper reviews the simulations of catheter ablation in computer models of the atria, from the first attempts to the most recent anatomical models. It describes how postulated substrates of atrial fibrillation can be incorporated into mathematical models, how modelling studies can be designed to test ablation strategies, what their current trade-offs and limitations are, and what clinically relevant lessons can be learnt from these simulations. Drawing a parallel between clinical and modelling studies, six ablation targets are considered: pulmonary vein isolation, linear ablation, ectopic foci, complex fractionated atrial electrogram, rotors and ganglionated plexi. The examples presented for each ablation target illustrate a major advantage of computer models, the ability to identify why a therapy is successful or not in a given atrial fibrillation substrate. The integration of pathophysiological data to create detailed models of arrhythmogenic substrates is expected to solidify the understanding of ablation mechanisms and to provide theoretical arguments supporting substrate-specific ablation strategies. [ABSTRACT FROM AUTHOR]

Background The benefits and risks of additional left atrium (LA) linear ablation in patients with paroxysmal atrial fibrillation (AF) remain unclear. Methods Randomized controlled trials were identified in the PubMed, Web of Science, Embase and Cochrane databases, and the relevant papers were examined. Pooled relative risks (RR) and 95% confidence interval (95% CI) were estimated using random effects models. The primary endpoint was the maintenance of sinus rhythm after a single ablation. Results Nine randomized controlled trials involving 1138 patients were included in this analysis. Additional LA linear ablation did not improve the maintenance of the sinus rhythm following a single procedure (RR, 1.03; 95% CI, 0.93–1.13; P = 0.60). A subgroup analysis demonstrated that all methods of additional linear ablation failed to improve the outcome. Additional linear ablation significantly increased the mean procedural time (166.53 ± 67.7 vs. 139.57 ± 62.44 min, P < 0.001), the mean fluoroscopy time (54.56 ± 38.7 vs. 44.32 ± 31.6 min, P < 0.001) and the mean radiofrequency (RF) energy application time (78.94 ± 28.39 vs. 59.74 ± 22.38 min, P < 0.001). No statistically significant differences in the rates of complications were noted (RR, 0.57; 95% CI, 0.27–1.19; P = 0.13). Conclusions Additional LA linear ablation did not exhibit any benefits in terms of sinus rhythm maintenance for paroxysmal AF patients following a single procedure. Additional linear ablation significantly increased the mean procedural, fluoroscopy and RF application times. This additional ablation was not associated with a statistically significant increase in complication rates. This finding must be confirmed by further large, high-quality clinical trials. [ABSTRACT FROM AUTHOR]

Objective: To review the literature systematically to determine whether noninvasive or invasive risk stratification, such as with an electrophysiological study of patients with asymptomatic pre-excitation, reduces the risk of arrhythmic events and improves patient outcomes.Methods: PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (all January 1, 1970, through August 31, 2014) were searched for randomized controlled trials and cohort studies examining noninvasive or invasive risk stratification in patients with asymptomatic pre-excitation. Studies were rejected for low-quality design or the lack of an outcome, population, intervention, or comparator of interest or if they were written in a language other than English.Results: Of 778 citations found, 9 studies met all the eligibility criteria and were included in this paper. Of the 9 studies, 1 had a dual design-a randomized controlled trial of ablation versus no ablation in 76 patients and an uncontrolled prospective cohort of 148 additional patients-and 8 were uncontrolled prospective cohort studies (n=1594). In studies reporting a mean age, the range was 32 to 50 years, and in studies reporting a median age, the range was 19 to 36 years. The majority of patients were male (range, 50% to 74%), and <10% had structural heart disease. In the randomized controlled trial component of the dual-design study, the 5-year Kaplan-Meier estimates of the incidence of arrhythmic events were 7% among patients who underwent ablation and 77% among patients who did not undergo ablation (relative risk reduction: 0.08; 95% confidence interval: 0.02 to 0.33; P<0.001). In the observational cohorts of asymptomatic patients who did not undergo catheter ablation (n=883, with follow-up ranging from 8 to 96 months), regular supraventricular tachycardia or benign atrial fibrillation (shortest RR interval >250 ms) developed in 0% to 16%, malignant atrial fibrillation (shortest RR interval ≤250 ms) in 0% to 9%, and ventricular fibrillation in 0% to 2%, most of whom were children in the last case.Conclusions: The existing evidence suggests risk stratification with an electrophysiological study of patients with asymptomatic pre-excitation may be beneficial, along with consideration of accessory-pathway ablation in those deemed to be at high risk of future arrhythmias. Given the limitations of the existing data, well-designed and well-conducted studies are needed. [ABSTRACT FROM AUTHOR]

Objective: To review the literature systematically to determine whether noninvasive or invasive risk stratification, such as with an electrophysiological study of patients with asymptomatic pre-excitation, reduces the risk of arrhythmic events and improves patient outcomes.Methods: PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (all January 1, 1970, through August 31, 2014) were searched for randomized controlled trials and cohort studies examining noninvasive or invasive risk stratification in patients with asymptomatic pre-excitation. Studies were rejected for low-quality design or the lack of an outcome, population, intervention, or comparator of interest or if they were written in a language other than English.Results: Of 778 citations found, 9 studies met all the eligibility criteria and were included in this paper. Of the 9 studies, 1 had a dual design-a randomized controlled trial of ablation versus no ablation in 76 patients and an uncontrolled prospective cohort of 148 additional patients-and 8 were uncontrolled prospective cohort studies (n=1,594). In studies reporting a mean age, the range was 32 to 50 years, and in studies reporting a median age, the range was 19 to 36 years. The majority of patients were male (range, 50% to 74%), and <10% had structural heart disease. In the randomized controlled trial component of the dual-design study, the 5-year Kaplan-Meier estimates of the incidence of arrhythmic events were 7% among patients who underwent ablation and 77% among patients who did not undergo ablation (relative risk reduction: 0.08; 95% confidence interval: 0.02 to 0.33; p<0.001). In the observational cohorts of asymptomatic patients who did not undergo catheter ablation (n=883, with follow-up ranging from 8 to 96 months), regular supraventricular tachycardia or benign atrial fibrillation (shortest RR interval >250 ms) developed in 0% to 16%, malignant atrial fibrillation (shortest RR interval ≤250 ms) in 0% to 9%, and ventricular fibrillation in 0% to 2%, most of whom were children in the last case.Conclusions: The existing evidence suggests risk stratification with an electrophysiological study of patients with asymptomatic pre-excitation may be beneficial, along with consideration of accessory-pathway ablation in those deemed to be at high risk of future arrhythmias. Given the limitations of the existing data, well-designed and well-conducted studies are needed. [ABSTRACT FROM AUTHOR]

The paper focus is on the generation of 3-D field models of probes for Radio-Frequency Ablation (RFA). The authors propose a multiphysics three-dimensional models for curved-electrode probes, which can be used to optimize placement and exploitation of the probes. The first model consists of tumor tissue and liver tissue. The second one is extended by fat tissue. The diameter of whole model is thirty centimetres, which corresponds to the waist size of the adult human. Both conduction field and transient thermal field in the tissues are simulated by means of finite-element method. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests a link between atrial fibrillation and subsequent development of dementia. While a majority of risk can be attributed to cardioembolic stroke secondary to atrial fibrillation, additional risk is apparent, and may be driven by vascular inflammation and changes in cerebral perfusion. Medical therapies including anticoagulation, statin therapy, and angiotensin-renin-aldosterone axis antagonists may reduce dementia risk. Procedural therapies such as atrial fibrillation catheter ablation and left atrial appendage closure may also prove to be important mediators of acute and long-term risk. In this paper, we review the data supporting a link between atrial fibrillation and dementia syndromes, pathophysiologic mechanisms and the potential roles of medical and procedural therapies at reducing such risk. [ABSTRACT FROM AUTHOR]

Objectives High ligation and stripping was compared to endovenous laser ablation for the therapy of great saphenous vein varicosity. Long-term efficacy was assessed in terms of avoidance of inguinal reflux and mechanisms of recurrence were investigated. Design Multicentre, randomised, three-arm, parallel trial.Materials and methods A total of 449 patients were randomised into three different treatment groups: high ligation and stripping group (n = 159), endovenous laser ablation group (n = 142; 980 nm, 30 W continuous mode, bare fibre) or a combination of laser ablation with high ligation (endovenous laser ablation group/ high ligation group, n = 148). Patients were examined clinically and by duplex ultrasound once a year. The primary end point of this study is inguinal reflux at the saphenofemoral junction after 2 years. This paper presents secondary data on sonographically determined inguinal reflux and clinical recurrences in the treated area after up to 6 years of follow-up. Results Median time to follow-up was 4.0 years; the mean time follow-up 3.6 years. Follow-up rates were: 2 years 74%, 3 years 47%, 4 years 39%, 5 years 36% and 6 years 31%. Most reflux into the great saphenous vein appeared in the endovenous laser ablation group (after 6 years: high ligation/stripping versus endovenous laser ablation p = 0.0102; high ligation/endovenous laser ablation vs. endovenous laser ablation p < 0.0002). Furthermore, more refluxive side branches were also observed in the endovenous laser ablation group (after 6 years high ligation/stripping vs. endovenous laser ablation p = 0.0569; high ligation/endovenous laser ablation vs. endovenous laser ablation p = 0.0111). In terms of clinical recurrence during the 6 years post therapy, no significant differences between the three treatment groups were observed (p values from log-rank test: high ligation/stripping vs. endovenous laser ablation p = 0.5479; high ligation/stripping vs. high ligation/endovenous laser ablation p = 0.2324; high ligation/endovenous laser ablation vs. endovenous laser ablation p = 0.0848). The postoperative decline and later development in Class C (clinical etiological anatomical pathological) went parallel in all groups. Conclusions Clinical recurrence appears with the same frequency in all three treatment groups, but the responsible pathological mechanisms seem to differ. Most reflux into the great saphenous vein and side branches appears after endovenous laser ablation, whereas more saphenofemoral junction-independent recurrences are seen after high ligation/stripping. [ABSTRACT FROM AUTHOR]

Vascular compression has been reported to be the most common reason for vago-glossopharyngeal neuralgia (VGN). The treatment may include medications, ganglion blockade with a radiofrequency ablation, and microvascular decompression (MVD). A review of the literature reveals that VGN may develop due to choroid plexus compression, and the number of reported cases is very limited. The current case is the fifth in the relevant literature. In this paper, choroid plexus compression has been shown intraoperatively during the treatment of rare idiopathic VGN using MVD. Complaints of the patient have been resolved following the choroid plexus excision. [ABSTRACT FROM AUTHOR]

The establishment of radiofrequency catheter ablation techniques as the mainstay in the treatment of tachycardia has renewed new interest in cardiac anatomy. The interventional arrhythmologist has drawn attention not only to the gross anatomic details of the heart but also to architectural and histological characteristics of various cardiac regions that are relevant to the development or recurrence of tachyarrhythmias and procedural related complications of catheter ablation. In this review, therefore, we discuss some anatomic landmarks commonly used in catheter ablations including the terminal crest, sinus node region, Koch’s triangle, cavotricuspid isthmus, Eustachian ridge and valve, pulmonary venous orifices, venoatrial junctions, and ventricular outflow tracts. We also discuss the anatomical features of important structures in the vicinity of the atria and pulmonary veins, such as the esophagus and phrenic nerves. This paper provides basic anatomic information to improve understanding of the mapping and ablative procedures for cardiac interventional electrophysiologists. [ABSTRACT FROM AUTHOR]

This paper presents the design and construction of a pair of figure-of-eight coils, coupled by magnetic resonance coupling (MRC), which could generate (150 V/m per Ampere) electric field at the focal points for electromagnetic therapy related applications. The E field generated at the targeted site would be significantly enhanced under the same amount of current flowing through the MRC figure-of-eight coils compared to normal coils, due to the superposition of E field contributed by the coils. Furthermore, the MRC figure-of-eight coil is designed and the results are verified in theory, simulation, and experiments. In the ex vivo tissue measurement, 35% current and 82% ohmic power improvements were observed. Since it can enhance the current and ohmic power, the MRC figure-of-eight coils are promising solutions for electromagnetic therapy applications. The potential applications of the coils include noninvasive radio frequency (RF) stimulation, thermoacoustic imaging, electromagnetic field therapies, and RF ablation, etc. [ABSTRACT FROM AUTHOR]

Objective: The only curative treatment for primary and secondary hepatic malignancies is surgery and liver transplantation. Thus, the majority of the patients are not candidates for resection, and there is a lack of organs. For these reasons, alternative treatment modalities such as radiofrequency ablation (RFA) are employed. The objective of this paper is to evaluate the incidence and types of complications related to open and percutaneous RFA. Method: This is a retrospective study of patients with hepatic malignancies treated by RFA. Tumor size, location, numbers of nodules, approach, histology and associated procedures were analyzed and correlated to complications. Results: A total of 151 patients with primary and secondary hepatic malignancies were included: 58 with hepatocellular carcinoma (HCC), 68 with metastases from colorectal cancer and 25 with other types of tumors. Complications occurred in 24.5% of the patients, mostly (58.9%) in those with HCC. Ascites was the most common complication, followed by wound infection. The only two significant factors associated with complications were the presence of HCC (p = 0.0087) and two or more lesions (p = 0.0323). The mortality rate was 0.69%. Conclusion: RFA is a safe technique, but complications may occur and are multifactorial. Appropriate patient selection, early complication recognition and adequate treatment are essential. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Given the high incidence of atrial fibrillation (AF) in the surgical population and the associated morbidity, physicians managing these complicated patients in the perioperative period need to be aware of the new and emerging trends in its therapy. The cornerstones of AF management have always been rate/rhythm control as well as anticoagulation. Restoration of sinus rhythm remains the fundamental philosophy as it maintains the atrial contribution to cardiac output and improves ventricular function. The recent years have seen a dramatic increase in the number of randomized AF trials that have made significant advances to our understanding of both pharmacologic and procedural management, from the introduction of the new generation of oral anticoagulants (NOAC's) to catheter approaches for AF ablation. This paper will summarize the newest data that will affect the perioperative management of these patients. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this paper was to evaluate the effectiveness in day clinics of microwave endometrial ablation (MEA) on transcervical microwave myolysis for patients with menorrhagia caused by submucosal myomas.Materials and methods: Thirty-five outpatients (average age 44.8 ± 5.2 years (mean ± SD), range 34–58) with a single submucosal myoma that was 4–7 cm (5.5 ± 2.1 cm) in size underwent MEA with transcervical microwave myolysis using a specifically developed transabdominal ultrasound probe attachment for transcervical puncture. Primary outcomes were the changes in the blood haemoglobin level and the volume of myoma before and after the treatment. Secondary outcomes were the improvement in menorrhagia and satisfaction after the operation, assessed by visual analogue scale (VAS).Results: The mean operation time was 27.9 ± 13.6 min. The myomas had shrunk by 56.2% at 3 months and 73.8% at ≥6 months after the operation. Blood haemoglobin levels had increased significantly at 3 months (10.2 ± 2.0 vs. 12.7 ± 1.2,p < 0.001). The average VAS assessment of menstrual bleeding had decreased to 1.7 ± 1.7 at 3 months after the operation (preoperative VAS = 10). The average VAS score for feelings of satisfaction 3 months after the operation was 9.8 ± 0.5 (full score = 10).Conclusions: MEA with transcervical microwave myolysis is a feasible and effective procedure in a day surgery clinic for menorrhagia caused by submucosal myomas. The procedure may be an alternative to hysterectomy for menorrhagia caused by submucosal myomas in women during the perimenopausal period. [ABSTRACT FROM PUBLISHER]