Clinical and Procedural Effects of Transitioning to Contact Force Guided Ablation for Atrial Fibrillation.

Background: A major innovation in atrial fibrillation (AF) ablation has been the introduction of contact force (CF) sensing catheters. Objective: To evaluate procedural and clinical effects of transitioning to CF-guided AF ablation. Methods: Consecutive AF ablation patients were studiedduring the period of time of transitioning from a non-CF to CF sensing catheter. Procedural data recorded was total radiofrequency time, time to isolate the left pulmonary veins (LPVs), and time to isolate the right pulmonary veins (RPVs). Clinically, the 3 and 12-month maintenance of sinus rhythm was noted and compared by: paroxysmal vs. persistent AF; CT scan LA volume more or less than 150 cc; CHA2DS2VASC more or less than 2; and LVEF more or less than 55%. Safety data was recorded as well. Results: Total ablation times were shorter (113 vs.146 min, p=0.011)when using the CF catheters compared to non-CF ablations. This was driven by a decrease in both LPV (46 vs.72 min, p\u3c0.001) and RPV time (54 vs. 75 min, p=0.002).The use of CF catheter did not change the overall percentage of patients in sinus rhythm at 3 and 12-months of follow up. However, sinus rhythm was more frequent at 12 months with CF ablation inpatients with an LA volume of more than 150 cc when compared to non-CF ablation (84.6% and 52.4%, p=0.03). There was no difference in outcomes with stratification by CHA2DS2VASC score or LVEF. No significant difference in complications was noted. Conclusions: For AF ablation, the initial use of CF-sensing technology reduced procedure times with similar overall sinus rhythm maintenance at 3 and 12 months. CF improved 12-month outcomes in patients with an enlarged LA

Pacemapping

Pacemapping (PM) is an electrophysiologic technique designed to help locating tachycardia sources by stimulating at different endocardial sites in order to reproduce the clinical tachycardia characteristics. A recorded electrocardiogram (ECG) during the clinical tachycardia has been conventionally used as reference. Yet, endocardial activation pattern during tachycardia may be utilized as well to guide the procedure. In focal tachycardia ablation, PM guide has consistently provided remarkable outcomes1, while outcomes in reentrant tachycardia ablation are less favourabl

Contact force sensing in ablation of ventricular arrhythmias using a 56-hole open-irrigation catheter: a propensity-matched analysis.

PURPOSE: The effect of adding contact force (CF) sensing to 56-hole tip irrigation in ventricular arrhythmia (VA) ablation has not been previously studied. We aimed to compare outcomes with and without CF sensing in VA ablation using a 56-hole radiofrequency (RF) catheter. METHODS: A total of 164 patients who underwent first-time VA ablation using Thermocool SmartTouch Surround Flow (TC-STSF) catheter (Biosense-Webster, Diamond Bar, CA, USA) were propensity-matched in a 1:1 fashion to 164 patients who had first-time ablation using Thermocool Surround Flow (TC-SF) catheter. Patients were matched for age, gender, cardiac aetiology, ejection fraction and approach. Acute success, complications and long-term follow-up were compared. RESULTS: There was no difference between procedures utilising either TC-SF or TC-STSF in acute success (TC-SF: 134/164 (82%), TC-STSF: 141/164 (86%), p = 0.3), complications (TC-SF: 11/164 (6.7%), TC-STSF: 11/164 (6.7%), p = 1.0) or VA-free survival (TC-SF: mean arrhythmia-free survival time = 5.9 years, 95% CI = 5.4-6.4, TC-STSF: mean = 3.2 years, 95% CI = 3-3.5, log-rank p = 0.74). Fluoroscopy time was longer in normal hearts with TC-SF (19 min, IQR: 14-30) than TC-STSF (14 min, IQR: 8-25; p = 0.04). CONCLUSION: Both TC-SF and TC-STSF catheters are safe and effective in treating VAs. The use of CF sensing catheters did not improve safety or acute and long-term outcomes, but reduced fluoroscopy time in normal heart VA

The clinical effectiveness and cost-effectiveness of ablative therapies in the management of liver metastases: systematic review and economic evaluation

Background: Many deaths from cancer are caused by metastatic burden. Prognosis and survival rates vary, but survival beyond 5 years of patients with untreated metastatic disease in the liver is rare. Treatment for liver metastases has largely been surgical resection, but this is feasible in only approximately 20–30% of people. Non-surgical alternatives to treat some liver metastases can include various forms of ablative therapies and other targeted treatments.Objectives: To evaluate the clinical effectiveness and cost-effectiveness of the different ablative and minimally invasive therapies for treating liver metastases.Data sources: Electronic databases including MEDLINE, EMBASE and The Cochrane Library were searched from 1990 to September 2011. Experts were consulted and bibliographies checked.Review methods: Systematic reviews of the literature were undertaken to appraise the clinical effectiveness and cost-effectiveness of ablative therapies and minimally invasive therapies used for people with liver metastases. Studies were any prospective study with sample size greater than 100 participants. A probabilistic model was developed for the economic evaluation of the technologies where data permitted.Results: The evidence assessing the clinical effectiveness and cost-effectiveness of ablative and other minimally invasive therapies was limited. Nine studies of ablative therapies were included in the review; each had methodological shortcomings and few had a comparator group. One randomised controlled trial (RCT) of microwave ablation versus surgical resection was identified and showed no improvement in outcomes compared with resection. In two prospective case series studies that investigated the use of laser ablation, mean survival ranged from 41 to 58 months. One cohort study compared radiofrequency ablation with surgical resection and five case series studies also investigated the use of radiofrequency ablation. Across these studies the median survival ranged from 44 to 52 months. Seven studies of minimally invasive therapies were included in the review. Two RCTs compared chemoembolisation with chemotherapy only. Overall survival was not compared between groups and methodological shortcomings mean that conclusions are difficult to make. Two case series studies of laser ablation following chemoembolisation were also included; however, these provide little evidence of the use of these technologies in combination. Three RCTs of radioembolisation were included. Significant improvements in tumour response and time to disease progression were demonstrated; however, benefits in terms of survival were equivocal. An exploratory survival model was developed using data from the review of clinical effectiveness. The model includes separate analyses of microwave ablation compared with surgery and radiofrequency ablation compared with surgery and one of radioembolisation in conjunction with hepatic artery chemotherapy compared with hepatic artery chemotherapy alone. Microwave ablation was associated with an incremental cost-effectiveness ratio (ICER) of £3664 per quality-adjusted life-year (QALY) gained, with microwave ablation being associated with reduced cost but also with poorer outcome than surgery. Radiofrequency ablation compared with surgical resection for solitary metastases < 3 cm was associated with an ICER of –£266,767 per QALY gained, indicating that radiofrequency ablation dominates surgical resection. Radiofrequency ablation compared with surgical resection for solitary metastases ? 3 cm resulted in poorer outcomes at lower costs and a resultant ICER of £2538 per QALY gained. Radioembolisation plus hepatic artery chemotherapy compared with hepatic artery chemotherapy was associated with an ICER of £37,303 per QALY gained.Conclusions: There is currently limited high-quality research evidence upon which to base any firm decisions regarding ablative therapies for liver metastases. Further trials should compare ablative therapies with surgery, in particular. A RCT would provide the most appropriate design for undertaking any further evaluation and should include a full economic evaluation, but the group to be randomised needs careful selection.Source of funding: Funding for this study was provided by the Health Technology Assessment programme of the National Institute for Health Research

Monitoring thermal ablation via microwave tomography. An ex vivo experimental assessment

Thermal ablation treatments are gaining a lot of attention in the clinics thanks to their reduced invasiveness and their capability of treating non-surgical patients. The effectiveness of these treatments and their impact in the hospital's routine would significantly increase if paired with a monitoring technique able to control the evolution of the treated area in real-time. This is particularly relevant in microwave thermal ablation, wherein the capability of treating larger tumors in a shorter time needs proper monitoring. Current diagnostic imaging techniques do not provide effective solutions to this issue for a number of reasons, including economical sustainability and safety. Hence, the development of alternative modalities is of interest. Microwave tomography, which aims at imaging the electromagnetic properties of a target under test, has been recently proposed for this scope, given the significant temperature-dependent changes of the dielectric properties of human tissues induced by thermal ablation. In this paper, the outcomes of the first ex vivo experimental study, performed to assess the expected potentialities of microwave tomography, are presented. The paper describes the validation study dealing with the imaging of the changes occurring in thermal ablation treatments. The experimental test was carried out on two ex vivo bovine liver samples and the reported results show the capability of microwave tomography of imaging the transition between ablated and untreated tissue. Moreover, the discussion section provides some guidelines to follow in order to improve the achievable performances

The year in cardiology: arrhythmias and pacing.

During this last year, there has been much progress with regard to anticoagulant and ablation therapy for atrial fibrillation (AF). Apart from recently issued European Society of Cardiology Guidelines for the management of patients with supraventricular arrhythmias, there has been little progress in research in this field. Ventricular arrhythmias and device therapy have seen modest progress

Short and Intermediate Term Outcomes of the Convergent Procedure: Initial Experience in a Tertiary Referral Center

PURPOSE: The Convergent procedure is a hybrid, multidisciplinary treatment for symptomatic atrial fibrillation (AF) consisting of minimally invasive surgical epicardial ablation and percutaneous/catheter endocardial ablation. We investigated outcomes following introduction of the Convergent procedure at our institution. METHODS: Retrospective study examining single-center outcomes. Demographic, procedural, and post-procedural variables were collected with follow-up data obtained at 3, 6, and 12 months. RESULTS: In all, 36 patients with paroxysmal (11%) or persistent/long-standing persistent (89%) AF underwent the Convergent procedure. 36% also underwent concomitant left atrial appendage (LAA) exclusion by thoracoscopic placement of an epicardial clip. Mean age 60.6 ± 8.0 years with mean arrhythmia burden of 3.9 ± 2.7 years. All patients had failed prior attempts at medical management, 81% had failed prior cardioversion, and 17% had failed prior catheter ablation. Convergent was performed successfully in all patients with no peri-procedural deaths or major complications. At 3 and 12 months, 77.8% and 77.3% of patients, respectively, were free from symptomatic arrhythmia. 65.8% were off anti-arrhythmic medication at 12 months. CONCLUSIONS: The Convergent procedure is safe and has good short- and intermediate-term clinical success rates. This unique hybrid approach combines strengths of surgical and catheter ablation and should be part of any comprehensive AF treatment program

Hysterectomy, endometrial ablation, and levonorgestrel releasing intrauterine system (Mirena) for treatment of heavy menstrual bleeding : cost effectiveness analysis

Peer reviewedPublisher PD

A Surgical Perspective on Targeted Therapy of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC), the second leading cause of cancer deaths worldwide, is difficult to treat and highly lethal. Since HCC is predominantly diagnosed in patients with cirrhosis, treatment planning must consider both the severity of liver disease and tumor burden. To minimize the impact to the patient while treating the tumor, techniques have been developed to target HCC. Anatomical targeting by surgical resection or locoregional therapies is generally reserved for patients with preserved liver function and minimal to moderate tumor burden. Patients with decompensated cirrhosis and small tumors are optimal candidates for liver transplantation, which offers the best chance of long-term survival. Yet, only 20%-30% of patients have disease amenable to anatomical targeting. For the majority of patients with advanced HCC, chemotherapy is used to target the tumor biology. Despite these treatment options, the five-year survival of patients in the United States with HCC is only 16%. In this review we provide a comprehensive overview of current approaches to target HCC. We also discuss emerging diagnostic and prognostic biomarkers, novel therapeutic targets identified by recent genomic profiling studies, and potential applications of immunotherapy in the treatment of HCC