Predictive utility of the impedance drop on AF recurrence using digital intraprocedural data linked to electronic health record data.

Background: Local impedance drop in cardiac tissue during catheter ablation may be a valuable measure to guide atrial fibrillation (AF) ablation procedures for greater effectiveness. Objective: The study sought to assess whether local impedance drop during catheter ablation to treat AF predicts 1-year AF recurrence and what threshold of impedance drop is most predictive. Methods: We identified patients with AF undergoing catheter ablation in the Mercy healthcare system. We downloaded AF ablation procedural data recorded by the CARTO system from a cloud-based analytical tool (CARTONET) and linked them to individual patient electronic health records. Average impedance drops in anatomical region of right and left pulmonary veins were calculated. Effectiveness was measured by a composite outcome of repeat ablation, AF rehospitalization, direct current cardioversion, or initialization of a new antiarrhythmic drug post-blanking period. The association between impedance drop and 1-year AF recurrence was assessed by logistic regression adjusting for demographics, clinical, and ablation characteristics. Bootstrapping was used to determine the most predictive threshold for impedance drop based on the Youden index. Results: Among 242 patients, 23.6% (n = 57) experienced 1-year AF recurrence. Patients in the lower third vs upper third of average impedance drop had a 5.9-fold (95% confidence interval [CI] 1.81-21.8) higher risk of recurrence (37.0% vs 12.5%). The threshold of 7.2 Ω (95% CI 5.75-7.7 Ω) impedance drop best predicted AF recurrence, with sensitivity of 0.73 and positive predictive value of 0.33. Patients with impedance drop ≤7.2 Ω had 3.5-fold (95% CI 1.39-9.50) higher risk of recurrence than patients with impedance drop >7.2 Ω, and there was no statistical difference in adverse events between the 2 groups of patients. Sensitivity analysis on right and left wide antral circumferential ablation impedance drop was consistent. Conclusion: Average impedance drop is a strong predictor of clinical success in reducing AF recurrence but as a single criterion for predicting recurrence only reached 73% sensitivity and 33% positive predictive value.

Does radiofrequency ablation procedural data improve the accuracy of identifying atrial fibrillation recurrence?

Radiofrequency ablation (RFA) using the CARTO 3D mapping system is a common approach for pulmonary vein isolation to treat atrial fibrillation (AF). Linkage between CARTO procedural data and patients' electronical health records (EHR) provides an opportunity to identify the ablation-related parameters that would predict AF recurrence. The objective of this study is to assess the incremental accuracy of RFA procedural data to predict post-ablation AF recurrence using machine learning model. Procedural data generated during RFA procedure were downloaded from CARTONET and linked to deidentified Mercy Health EHR data. Data were divided into train (70%) and test (30%) data for model development and validation. Automate machine learning (AutoML) was used to predict 1 year AF recurrence, defined as a composite of repeat ablation, electrical cardioversion, and AF hospitalization. At first, AutoML model only included Patients' demographic and clinical characteristics. Second, an AutoML model with procedural variables and demographical/clinical variables was developed. Area under receiver operating characteristic curve (AUROC) and net reclassification improvement (NRI) were used to compare model performances using test data. Among 306 patients, 67 (21.9%) patients experienced 1-year AF recurrence. AUROC increased from 0.66 to 0.78 after adding procedural data in the AutoML model based on test data. For patients with AF recurrence, NRI was 32% for model with procedural data. Nine of 10 important predictive features were CARTO procedural data. From CARTO procedural data, patients with lower contact force in right inferior site, long ablation duration, and low number of left inferior and right roof lesions had a higher risk of AF recurrence. Patients with persistent AF were more likely to have AF recurrence. The machine learning model with procedural data better predicted 1-year AF recurrence than the model without procedural data. The model could be used for identification of patients with high risk of AF recurrence post ablation.

Using real-world data from health systems to evaluate the safety and effectiveness of a catheter to treat ischemic ventricular tachycardia.

BACKGROUND: The ThermoCool STSF catheter is used for ablation of ischemic ventricular tachycardia (VT) in routine clinical practice, although outcomes have not been studied and the catheter does not have Food and Drug Administration (FDA) approval for this indication. We used real-world health system data to evaluate its safety and effectiveness for this indication. METHODS: Among patients undergoing ischemic VT ablation with the ThermoCool STSF catheter pooled across two health systems (Mercy Health and Mayo Clinic), the primary safety composite outcome of death, thromboembolic events, and procedural complications within 7 days was compared to a performance goal of 15%, which is twice the expected proportion of the primary composite safety outcome based on prior studies. The exploratory effectiveness outcome of rehospitalization for VT or heart failure or repeat VT ablation at up to 1 year was averaged across health systems among patients treated with the ThermoCool STSF vs. ST catheters. RESULTS: Seventy total patients received ablation for ischemic VT using the ThermoCool STSF catheter. The primary safety composite outcome occurred in 3/70 (4.3%; 90% CI, 1.2-10.7%) patients, meeting the pre-specified performance goal, p = 0.0045. At 1 year, the effectiveness outcome risk difference (STSF-ST) at Mercy was - 0.4% (90% CI: - 25.2%, 24.3%) and at Mayo Clinic was 12.6% (90% CI: - 13.0%, 38.4%); the average risk difference across both institutions was 5.8% (90% CI: - 12.0, 23.7). CONCLUSIONS: The ThermoCool STSF catheter was safe and appeared effective for ischemic VT ablation, supporting continued use of the catheter and informing possible FDA label expansion. Health system data hold promise for real-world safety and effectiveness evaluation of cardiovascular devices.

Integrating real-world data to assess cardiac ablation device outcomes in a multicenter study using the OMOP common data model for regulatory decisions: implementation and evaluation.

The objective of this study is to describe application of the Observational Medical Outcomes Partnership (OMOP) common data model (CDM) to support medical device real-world evaluation in a National Evaluation System for health Technology Coordinating Center (NESTcc) Test-Case involving 2 healthcare systems, Mercy Health and Mayo Clinic. CDM implementation was coordinated across 2 healthcare systems with multiple hospitals to aggregate both medical device data from supply chain databases and patient outcomes and covariates from electronic health record data. Several data quality assurance (QA) analyses were implemented on the OMOP CDM to validate the data extraction, transformation, and load (ETL) process. OMOP CDM-based data of relevant patient encounters were successfully established to support studies for FDA regulatory submissions. QA analyses verified that the data transformation was robust between data sources and OMOP CDM. Our efforts provided useful insights in real-world data integration using OMOP CDM for medical device evaluation coordinated across multiple healthcare systems.

Catheter ablation using advanced porous tip contact force-sensing radiofrequency catheter: Impact on health care utilization among patients with persistent atrial fibrillation.

Background: Catheter ablation (CA) is an effective treatment for patients with persistent atrial fibrillation (PsAF); however, little is known about its impact on health care utilization for patients with PsAF. The ThermoCool SmartTouch SF (STSF) catheter (Biosense Webster) incorporates an advanced porous tip and contact force-sensing technology. Objective: The purpose of this study was to determine health care utilization among patients with PsAF who underwent ablation with the STSF catheter. Methods: A retrospective cohort study using the Premier Healthcare Database identified patients with PsAF undergoing CA with the STSF catheter in inpatient and outpatient settings. The proportion of patients experiencing AF-related inpatient admissions, outpatient admissions, emergency department (ED) visits, electrical cardioversion, and a composite outcome in the 12 months pre- vs postablation were compared using the McNemar test. Subanalyses were performed on study outcomes by race/ethnicity. Results: The final sample included 3077 patients (mean age 65.9 years; 31.7% female). Among patients with PsAF undergoing ablation with the STSF catheter, relative reductions in health care utilization in the 12 months post- vs preablation included 55.3% in AF-related inpatient admissions (P <.0001), 38.9% in outpatient admissions (P <.0001), 52.4% in ED visits (P <.0001), and 61.2% in electrical cardioversions (P <.0001). Composite outcome utilization in the 12 months post- vs preablation declined by 40.2% (P <.0001) for the overall cohort, 40.0% for White patients (P <.0001), 52.2% for Black patients (P <.0001), and 50.1% for Asian patients (P = .032). Conclusion: Significant improvements in health care utilization were observed among PsAF patients who underwent ablation using the STSF catheter. Improvements were particularly marked in underrepresented racial and ethnic groups.

Safety and Effectiveness of a Catheter With Contact Force and 6-Hole Irrigation for Ablation of Persistent Atrial Fibrillation in Routine Clinical Practice.

Importance: The ThermoCool SmartTouch catheter (ablation catheter with contact force and 6-hole irrigation [CF-I6]) is approved by the US Food and Drug Administration (FDA) for paroxysmal atrial fibrillation (AF) ablation and used in routine clinical practice for persistent AF ablation, although clinical outcomes for this indication are unknown. There is a need to understand whether data from routine clinical practice can be used to conduct regulatory-grade evaluations and support label expansions. Objective: To use health system data to compare the safety and effectiveness of the CF-I6 catheter for persistent AF ablation with the ThermoCool SmartTouch SurroundFlow catheter (ablation catheter with contact force and 56-hole irrigation [CF-I56]), which is approved by the FDA for this indication. Design, Setting, and Participants: This retrospective, comparative-effectiveness cohort study included patients undergoing catheter ablation for persistent AF at Mercy Health or Mayo Clinic from January 1, 2014, to April 30, 2021, with up to a 1-year follow-up using electronic health record data. Exposures: Use of the CF-I6 or CF-I56 catheter. Main Outcomes and Measures: The primary safety outcome was a composite of death, thromboembolic events, and procedural complications within 7 to 90 days. The exploratory effectiveness outcome was a composite of AF-related hospitalization events after a 90-day blanking period. Propensity score weighting was used to balance baseline covariates. Risk differences were estimated between catheter groups and averaged across the 2 health care systems, testing for noninferiority of the CF-I6 vs the CF-I56 catheter with respect to the safety outcome using 2-sided 90% CIs. Results: Overall, 1450 patients (1034 [71.3%] male; 1397 [96.3%] White) underwent catheter ablation for persistent AF, including 949 at Mercy Health (186 CF-I6 and 763 CF-I56; mean [SD] age, 64.9 [9.2] years) and 501 at Mayo Clinic (337 CF-I6 and 164 CF-I56; mean [SD] age, 63.7 [9.5] years). A total of 798 (55.0%) had been treated with class I or III antiarrhythmic drugs before ablation. The safety outcome (CF-I6 - CF-I56) was similar at both Mercy Health (1.3%; 90% CI, -2.1% to 4.6%) and Mayo Clinic (-3.8%; 90% CI, -11.4% to 3.7%); the mean difference was noninferior, with a mean of 0.5% (90% CI, -2.6% to 3.5%; P < .001). The effectiveness was similar at 12 months between the 2 catheter groups (mean risk difference, -1.8%; 90% CI, -7.3% to 3.7%). Conclusions and Relevance: In this cohort study, the CF-I6 catheter met the prespecified noninferiority safety criterion for persistent AF ablation compared with the CF-I56 catheter, and effectiveness was similar. This study demonstrates the ability of electronic health care system data to enable safety and effectiveness evaluations of medical devices.

Cannabis, cannabinoids, and cannabis-based medicines: future research directions for analgesia.

The use of cannabis spans thousands of years and encompasses almost all dimensions of the human experience, including consumption for recreational, religious, social, and medicinal purposes. Its use in the management of pain has been anecdotally described for millennia. However, an evidence base has only developed over the last 100 years, with an explosion in research occurring in the last 20-30 years, as more states in the USA as well as countries worldwide have legalized and encouraged its use in pain management. Pain remains one of the most common reasons for individuals deciding to use cannabis medicinally. However, cannabis remains illegal at the federal level in the USA and in most countries of the world, making it difficult to advance quality research on its efficacy for pain treatment. Nonetheless, new products derived both from the cannabis plant and the chemistry laboratory are being developed for use as analgesics. This review examines the current landscape of cannabinoids research and future research directions in the management of pain.

What do patients want out of their Total Knee Arthroplasty?: An Indian perspective.

INTRODUCTION AND AIM: Total Knee Arthroplasty surgery is one of the most successful operations in orthopaedics. Still a sizable percentage of patients remain dissatisfied. Various studies have been conducted to analyse the red flags associated with poor outcome. In this study we tried to have insight on actual requirements of Indian patients from TKA operation. MATERIAL & METHODS: 300 patients undergoing TKA were studied by way of patient expectation feedback form. The form had various patient related capture points. It had a leading question: What are your expectations from TKA? They were asked to rank the 5 most important options in the order of importance. The patient expectation form was distributed and collected by an independent observer. RESULTS: 70% of patients ranked relief of pain as the most important expectation. 20% reported improvement in walking as the number one expectation. Nearly equal number listed improvement in walking and ease of doing day-to-day activities as the second most important expectation. This was followed by improvement in climbing the stairs and improvement in quality of life. Correction of deformity and no pain while squatting and getting up from sitting position ranked at the bottom. CONCLUSION: Our study shows that the primary expectations of Indian population from their TKA are relief from pain and improvement in walking. Secondary expectations include ease of doing day-to-day activities and improvement in quality of life.

Effect of Preoperative Diabetes on the Achievement of Forgotten Knee Status in Patients with Total Knee Arthroplasty.

BACKGROUND: Forgotten knee is the terminology which is used to describe a post-TKA patient who is completely unaware of his knee implant. The aim of the study is to determine whether preoperative diabetes negatively influences the achievement of forgotten knee status. METHODS: This is a retrospective cohort study. 300 patients (240 F:60 M) were studied. Patients were evaluated by an independent observer with FJS-12 score 2 weeks preop and at 6 weeks and 12 months after the operation. The patients with a FJS-12 score of ≥ 55 were considered to have achieved forgotten knee status. Out of 240 females, 96 had diabetes and out of 60 males, 18 had diabetes. Preoperative factors such as preop HBA1c, ROM, degree of deformity, VAS score and other associated co morbidities and postoperative factors such as HBA1c, ROM and hip-knee-ankle alignment were studied. Study was started with null hypothesis. The statistical difference was measured with Binominal proportion test and comparison of means t test. RESULTS: 96 out of 144 non-diabetic females (66.67%) and 51 out of 96 diabetic females (53%) achieved forgotten knee status (statistically significant, p value = 0.0336, Binominal proportion test). 27 out of 42 (65%) non-diabetic males and 12 out 18 diabetic males (66%) achieved forgotten knee status (p value = 0.9411). The FJS-12 score at 1 year for non-diabetic females and diabetic females was 58.6 mean ± 12.6 SD and 53.8 ± 17.6, respectively, which is statistically significant, p value 0.0145. The FJS-12 at 1 year in non-diabetic and diabetic males was 60.1 ± 14.8 and 59.6 ± 17.3, respectively, p value = 0.9097. CONCLUSION: Diabetic females have less chance of achieving a forgotten knee status than non-diabetic females. This understanding will help the operating surgeon in the preoperative patient counseling and modify the patient expectations.

Feasibility of capturing real-world data from health information technology systems at multiple centers to assess cardiac ablation device outcomes: A fit-for-purpose informatics analysis report.

OBJECTIVE: The study sought to conduct an informatics analysis on the National Evaluation System for Health Technology Coordinating Center test case of cardiac ablation catheters and to demonstrate the role of informatics approaches in the feasibility assessment of capturing real-world data using unique device identifiers (UDIs) that are fit for purpose for label extensions for 2 cardiac ablation catheters from the electronic health records and other health information technology systems in a multicenter evaluation. MATERIALS AND METHODS: We focused on data capture and transformation and data quality maturity model specified in the National Evaluation System for Health Technology Coordinating Center data quality framework. The informatics analysis included 4 elements: the use of UDIs for identifying device exposure data, the use of standardized codes for defining computable phenotypes, the use of natural language processing for capturing unstructured data elements from clinical data systems, and the use of common data models for standardizing data collection and analyses. RESULTS: We found that, with the UDI implementation at 3 health systems, the target device exposure data could be effectively identified, particularly for brand-specific devices. Computable phenotypes for study outcomes could be defined using codes; however, ablation registries, natural language processing tools, and chart reviews were required for validating data quality of the phenotypes. The common data model implementation status varied across sites. The maturity level of the key informatics technologies was highly aligned with the data quality maturity model. CONCLUSIONS: We demonstrated that the informatics approaches can be feasibly used to capture safety and effectiveness outcomes in real-world data for use in medical device studies supporting label extensions.

Study of Patients with Bilateral Knee Osteoarthritis Undergoing Total Knee Replacement Procedure with Coexisting Lumbar Spondylosis Symptoms.

STUDY DESIGN: This is a prospective cohort study involving patients who were followed for 2 years after total knee replacement (TKR) to determine changes in lumbar spine and knee symptoms. PURPOSE: The objectives of this study were to determine the percentage of patients undergoing bilateral TKR who present with coexisting lumbar spine problems and determine if TKR relieves lumbar spine symptoms. OVERVIEW OF LITERATURE: No studies quantify the percentage of TKR patients who experience relief of lumbar spine symptoms after TKR surgery. METHODS: The study included 200 patients (164 females, 36 males) undergoing primary TKR. Follow-up was performed at 4 weeks, 3, 6, 12, and 24 months. Lumbar spine and knee symptom improvements were assessed using the Oswestry Disability Index (ODI) and Oxford Knee Score, respectively. RESULTS: All 200 patients undergoing bilateral TKR presented with radiographic lumbar spine degenerative pathology; 60% (n=120) of the patients presented with moderate to severe clinical symptoms of lumbar spondylosis, including 54% (n=108) with degenerative lumbar spondylosis and lumbar canal stenosis and 6% (n=12) with degenerative spondylolisthesis. Of the 120 patients who presented with lumbar spine problems, 90% (n=108) reported improvement in their symptoms; the ODI score improved from 42.5%±4.1% preoperative score to 15.6%±2.3% postoperative score (p-value<0.001). Of the 12 patients with no improvement, 10 patients underwent percutaneous procedures for their lumbar spine pathology with good results, one patient underwent surgery, and one declined any intervention. CONCLUSIONS: A significant number of patients (60%) undergoing bilateral TKR also present with symptomatic lumbar spine problems. Patients with mild to moderate lumbar spine degenerative symptoms and no associated severe radiating pain on activity are more likely to experience relief of their symptoms post-TKR.

Home physiotherapy with vs. without supervision of physiotherapist for assessing manipulation under anaesthesia after total knee arthroplasty.

The aim of this retrospective cohort study was to compare home physiotherapy with or without supervision of physiotherapist for assessing manipulation under anaesthesia after total knee arthroplasty. METHODS: A total of 900 patients (including 810 females and 90 males) who had undergone total knee arthroplasty were divided into group A (n = 300) and group B (n = 600). Patients in group A had home physiotherapy on their own after discharge from hospital. The physiotherapist did not visit them at home. Patients in group B received home physiotherapy under supervision of physiotherapist for 6 weeks after discharge from hospital. Patients' age, range of motion of the knee, and forgotten joint score-12 were assessed. A p < 0.05 was considered statistically significant. RESULTS: In group A, the mean age was 69.1 ± 14.3 years (range: 58 to 82 years); in group B, the mean age was 66.5 ± 15.7 years (range: 56 to 83 years) (p > 0.05). Preoperatively, the mean range of motion of the knee in group A and B was 95.8° ± 18.1° and 95.4° ± 17.8°, respectively (p > 0.05). The mean forgotten joint score-12 of group A and B were 11.90 ± 11.3 and 11.72 ± 12.1 (p > 0.05), respectively. Six weeks after total knee arthroplasty, the mean ROM of the knee in group A and B was 109.7° ± 22.3° and 121° ± 21.5°, respectively (p < 0.05). The mean postoperative forgotten joint score-12 of the group A and B was 24.5 ± 16.4 and 25.6 ± 17.4, respectively (p > 0.05). The rate of manipulation under anaesthesia was 3% in group A and 0.2% in group B (p < 0.05). CONCLUSION: After total knee arthroplasty, frequent physiotherapist's instruction helps the patients improve knee exercises and therefore decrease the risk of revision surgery. The home physiotherapy under supervision of physiotherapist lowers the rate of manipulation under anaesthesia. LEVEL OF EVIDENCE: Therapeutic study, Level IIa.

Understanding the apprehension and concern haunting patients before a total knee arthroplasty.

PURPOSE: The aim of this prospective study was to understand the fear and apprehension factors that play on patient's mind before total knee arthroplasty. METHODS: This retrospective cohort study included 500 consecutive patients (375 females and 125 males) who were scheduled to undergo total knee arthroplasty the next day. The patients were asked to list the most important fear in their mind regarding the operation in descending order of importance. They were given a questionnaire form which contained several capture points, including age, gender, educational background, occupation, and provision of help at home. Preoperative pain was measured by using the visual analog score, and its influence on the patients' fear and apprehension factors was also measured. RESULTS: In this study, 58% of patients (50 males, 40%; 240 females, 64%) were fearful of the pain that they would experience after surgery and during the postoperative physiotherapy. The female patients showed more fear of pain than their male counterparts (P < 0.05). 18% of the patients (40 males, 32%; 50 females, 13%) listed whether they will be able to walk and perform activities of daily living after surgery as the most important fear. The male patients had more fear of returning to normal walking (P < 0.05). 20% of the patients (30 males, 24%; 70 females, 19%) were fearful about getting adequate home help after discharge from hospital (P > 0.05). 4% of patients were concerned about withstanding such a major operation. There was no difference between male and female patients (P > 0.05). CONCLUSION: The majority of the patients experience apprehension of pain in the perioperative period of TKA. Preoperative counseling benefits pain management by alleviating the patient's concerns about the fear of postoperative pain and apprehension of returning to normal walking.

Feasibility of using real-world data in the evaluation of cardiac ablation catheters: a test-case of the National Evaluation System for Health Technology Coordinating Center.

OBJECTIVES: To determine the feasibility of using real-world data to assess the safety and effectiveness of two cardiac ablation catheters for the treatment of persistent atrial fibrillation and ischaemic ventricular tachycardia. DESIGN: Retrospective cohort. SETTING: Three health systems in the USA. PARTICIPANTS: Patients receiving ablation with the two ablation catheters of interest at any of the three health systems. MAIN OUTCOME MEASURES: Feasibility of identifying the medical devices and participant populations of interest as well as the duration of follow-up and positive predictive values (PPVs) for serious safety (ischaemic stroke, acute heart failure and cardiac tamponade) and effectiveness (arrhythmia-related hospitalisation) clinical outcomes of interest compared with manual chart validation by clinicians. RESULTS: Overall, the catheter of interest for treatment of persistent atrial fibrillation was used for 4280 ablations and the catheter of interest for ischaemic ventricular tachycardia was used 1516 times across the data available within the three health systems. The duration of patient follow-up in the three health systems ranged from 91% to 97% at ≥7 days, 89% to 96% at ≥30 days, 77% to 90% at ≥6 months and 66% to 84% at ≥1 year. PPVs were 63.4% for ischaemic stroke, 96.4% for acute heart failure, 100% at one health system for cardiac tamponade and 55.7% for arrhythmia-related hospitalisation. CONCLUSIONS: It is feasible to use real-world health system data to evaluate the safety and effectiveness of cardiac ablation catheters, though evaluations must consider the implications of variation in follow-up and endpoint ascertainment among health systems.

CRP (C Reactive Protein) level after total knee replacement in Indian population--- does it follow Anglo-Saxon trend?

BACKGROUND: This study was to determine how C-reactive protein (CRP) responds after total knee replacement (TKR), including both unilateral and simultaneous bilateral TKR in Indian population and if it follows Anglo-Saxon trend. Published literature from North America and Europe shows CRP value peaks on the 2nd post-operative day and drops to normal by 6-8 weeks. We started the study with null hypothesis. MATERIAL AND METHODS: This is a prospective study, with 50 patients (all females, 25 received unilateral operations and 25 bilateral ones) included. CRP levels were measured, on the 2nd day, 8, 12 and 16 weeks after operation. RESULTS: In both groups, CRP level rose the 2nd post-operative day. The rise in CRP level was significantly higher in the simultaneous bilateral TKR group than in the unilateral TKR group. In unilateral cases, CRP on the 2nd postoperative day ranged from 65 to 110 mg/l with average level of 80 mg/ml. In bilateral TKR cases, CRP level on the 2nd postoperative day was between 110 and 180 mg/l with a mean of 140 mg/ml. The CRP level returned to normal in about 40% of unilateral TKR patients 8 weeks after operation, while in 92% (23 out of 25) of bilateral simultaneous TKR patients it stayed at a high level 8 weeks post-op and did not come back to normal. At 12 weeks CRP decreased to normal in all 100% of unilateral TKR patients and 32% of bilateral TKR patients. At 16 weeks, CRP was normal in all bilateral TKR patients. CONCLUSION: 60% of our unilateral TKR patients and 92% of our simultaneous bilateral TKR patients did not achieve a normal CRP 8 weeks after operation. These findings are significant as CRP is commonly used as a very sensitive indicator of postoperative joint infection. Hence we conclude that in the Indian TKR patients the CRP values take longer time to return to normal than in their Anglo-Saxon counterparts. Published results regarding the normal levels of CRP in unilateral TKR should not be extrapolated to simultaneous bilateral TKR patients.

Fluoroless catheter ablation in adults: a single center experience.

BACKGROUND: Ablation procedures for arrhythmias have increased in frequency and complexity over the last decade. Improvements in technology have allowed for less reliance on fluoroscopy to guide these procedures. Ablation without fluoroscopy has been reported in small cohorts. We report a single center experience of fluoroless ablation after adoption of this technique for all endovascular ablations. METHODS: This retrospective study evaluated 107 consecutive patients who underwent a catheter ablation procedure for an atrial or ventricular arrhythmias after adoption of a completely fluoroless technique. No fluoroscopy was used in any case. A mapping system was utilized in all cases. Intracardiac echocardiography (ICE) catheters were utilized in 75 of the ablation cases (70.4%). Of the 107 patients who underwent EP study, three patients did not undergo ablation as they were non-inducible for SVT. Of the remaining 104 patients, 56 patients (53.8%) underwent ablation for atrial fibrillation, 23 patients (22.1%) for SVT, 10 patients (9.6%) for lone atrial flutter, and 16 patients (15.4%) for a ventricular arrhythmia including PVC, idiopathic VT or ventricular tachycardia. RESULTS: Catheters were able to be placed in 100% of patients without complication. Time to placement in the coronary sinus was 2.1 min ± 1.4 min. Mean transseptal time was 3.54 min ± 3 min. Mean procedure time for all ablations was 2 h 6 min ± 50 min. There were no complications in the series of patients. CONCLUSIONS: Fluoroless ablation is feasible and safe with acceptable procedure times. Adoption of this technique is encouraged in order to eliminate unnecessary risk of fluoroscopy.

Rotors in patients with persistent atrial fibrillation: case report of a left atrial appendage rotor identified by a novel computational mapping algorithm integrated into 3-dimensional mapping and termination of atrial fibrillation with ablation.

Recent clinical trials using panoramic mapping techniques have shown success in targeting rotors and focal impulses in atrial fibrillation (AF). Ablations directed toward these organized sources improve outcomes in AF. The left atrial appendage (LAA) has been suspected as a possible extrapulmonary source of AF, and ablation within the LAA or electrical isolation of the LAA improves outcomes in certain cases. This case highlights a unique example of panoramic imaging created with a computational mapping algorithm integrated in 3-dimensional mapping, which identified rotors within the LAA. Furthermore, ablations performed near an identified rotor core within the LAA terminated AF.

Micropercutaneous nephrolithotomy (microperc) vs retrograde intrarenal surgery for the management of small renal calculi: a randomized controlled trial.

OBJECTIVE: To compare micropercutaneous nephrolithotomy (microperc) and retrograde intrarenal surgery (RIRS) for the management of renal calculi <1.5 cm with regard to stone clearance rates and surgical characteristics, complications and postoperative recovery. PATIENTS AND METHODS: Seventy patients presenting with renal calculi <1.5 cm were equally randomized to a microperc or a RIRS group between February 2011 and August 2012 in this randomized controlled trial. Randomization was based on centralized computer-generated numbers. Patients and authors assessing the outcomes were not blinded to the procedure. Microperc was performed using a 4.85-F (16-gauge) needle with a 272-µm laser fibre. RIRS was performed using a uretero-renoscope. Variables studied were stone clearance rates, operating time, need for JJ stenting, intra-operative and postoperative complications (according to the Clavien-Dindo classification system), surgeon discomfort score, postoperative pain score, analgesic requirement and hospital stay. Stone clearance was assessed using ultrasonography and X-ray plain abdominal film of kidney, ureter and bladder at 3 months. RESULTS: There were 35 patients in each group. All the patients were included in the final analysis. The stone clearance rates in the microperc and RIRS groups were similar (97.1 vs 94.1%, P = 1.0). The mean [sd] operating time was similar between the groups (51.6 [18.5] vs 47.1 [17.5], P = 0.295). JJ stenting was required in a lower proportion of patients in the microperc group (20 vs 62.8%, P < 0.001). Intra-operative complications were a minor pelvic perforation in one patient and transient haematuria in two patients, all in the microperc group. One patient in each group required conversion to miniperc. One patient in the microperc group needed RIRS for small residual calculi 1 day after surgery. The decrease in haemoglobin was greater in the microperc group (0.96 vs 0.56 g/dL, P < 0.001). The incidence of postoperative fever (Clavien I) was similar in the two groups (8.6 vs 11.4%, P = 1.0). None of the patients in the study required blood transfusion. The mean [sd] postoperative pain score at 24 h was slightly higher in the microperc group (1.9 [1.2] vs 1.6 [0.8], P = 0.045). The mean [sd] analgesic requirement was higher in the microperc group (90 [72] vs 40 [41] mg tramadol, P < 0.001). The mean [sd] hospital stay was similar in the two groups (57 [22] vs 48 [18] h, P = 0.08). CONCLUSIONS: Microperc is a safe and effective alternative to RIRS for the management of small renal calculi and has similar stone clearance and complication rates when compared to RIRS. Microperc is associated with higher haemoglobin loss, increased pain and higher analgesic requirements, while RIRS is associated with a higher requirement for JJ stenting.

A promoter polymorphism of the endothelial nitric oxide synthase gene is associated with reduced mRNA and protein expression in failing human myocardium.

BACKGROUND: Alterations of endothelial nitric oxide synthase (eNOS) enzyme activity via eNOS gene polymorphisms have been associated with significant cardiovascular morbidity and mortality. Both the thymidine to cytosine transition mutation (T(-786)-->C) in the promoter region and the missense mutation in the exon 7 coding region of the eNOS gene (G(894)-->T) have been associated with several cardiovascular disease states. We hypothesized that heart transplant recipients who carried at least 1 allele of either of the polymorphisms would have reduced myocardial tissue expression of eNOS measured in the explanted heart. METHODS AND RESULTS: Genomic DNA was isolated from myocardial tissue samples obtained from 43 explanted human hearts using standard methods. Regions of the eNOS gene were amplified from genomic DNA with a polymerase chain reaction using specific primers. Protein expression of eNOS was measured by Western blot analysis. There was a statistically significant decrease in mean eNOS expression in samples containing at least one allele for the T(-786)-->C promoter polymorphism (P=.04) compared with patients homozygous for the T allele. There was no change in eNOS expression associated with the G(894)-->T exonic polymorphisms. CONCLUSIONS: Our data show in failing human myocardium that the T(-786)-->C promoter polymorphism is associated with reduced eNOS expression, whereas the G(894)-->T polymorphism of exon 7 is not associated with change in either eNOS mRNA or protein expression. Reduced eNOS expression associated with the promoter polymorphism may contribute to the vascular, contractile, and autonomic responses to ventricular failure.