A new machine learning approach for predicting likelihood of recurrence following ablation for atrial fibrillation from CT.

OBJECTIVE: To investigate left atrial shape differences on CT scans of atrial fibrillation (AF) patients with (AF+) versus without (AF-) post-ablation recurrence and whether these shape differences predict AF recurrence. METHODS: This retrospective study included 68 AF patients who had pre-catheter ablation cardiac CT scans with contrast. AF recurrence was defined at 1 year, excluding a 3-month post-ablation blanking period. After creating atlases of atrial models from segmented AF+ and AF- CT images, an atlas-based implicit shape differentiation method was used to identify surface of interest (SOI). After registering the SOI to each patient model, statistics of the deformation on the SOI were used to create shape descriptors. The performance in predicting AF recurrence using shape features at and outside the SOI and eight clinical factors (age, sex, left atrial volume, left ventricular ejection fraction, body mass index, sinus rhythm, and AF type [persistent vs paroxysmal], catheter-ablation type [Cryoablation vs Irrigated RF]) were compared using 100 runs of fivefold cross validation. RESULTS: Differences in atrial shape were found surrounding the pulmonary vein ostia and the base of the left atrial appendage. In the prediction of AF recurrence, the area under the receiver-operating characteristics curve (AUC) was 0.67 for shape features from the SOI, 0.58 for shape features outside the SOI, 0.71 for the clinical parameters, and 0.78 combining shape and clinical features. CONCLUSION: Differences in left atrial shape were identified between AF recurrent and non-recurrent patients using pre-procedure CT scans. New radiomic features corresponding to the differences in shape were found to predict post-ablation AF recurrence.

A fast score test for generalized mixture models.

In biomedical studies, testing for homogeneity between two groups, where one group is modeled by mixture models, is often of great interest. This paper considers the semiparametric exponential family mixture model proposed by Hong et al. (2017) and studies the score test for homogeneity under this model. The score test is nonregular in the sense that nuisance parameters disappear under the null hypothesis. To address this difficulty, we propose a modification of the score test, so that the resulting test enjoys the Wilks phenomenon. In finite samples, we show that with fixed nuisance parameters the score test is locally most powerful. In large samples, we establish the asymptotic power functions under two types of local alternative hypotheses. Our simulation studies illustrate that the proposed score test is powerful and computationally fast. We apply the proposed score test to an UK ovarian cancer DNA methylation data for identification of differentially methylated CpG sites.

Repeat ablation or medical management alone for recurrent arrhythmias after ablation of persistent atrial fibrillation.

INTRODUCTION: Management of persistent atrial fibrillation (PersAF) remains challenging, and many patients are left on medical therapy after a failed first ablation. In patients with recurrent symptomatic arrhythmias after PersAF ablation, we aimed to compare outcomes of repeat ablation and medical therapy versus medical therapy alone. METHODS AND RESULTS: All 682 consecutive patients with recurrent symptomatic arrhythmia after a first ablation for PersAF at our institution (2005-2012) were included. Repeat ablation with continuation of medical therapy was performed in 364 patients (Group 1) and 318 were only medically managed (Group 2). The outcome of interest was freedom from arrhythmia recurrence beyond a 3-month blanking period. Separate analyses were performed to assess this endpoint totally off antiarrhythmics (primary endpoint) or alternatively with/without use of antiarrhythmics (secondary endpoint). Over a median follow-up of 26 months, 41.5% of Group 1 patients met the primary endpoint and remained free from arrhythmia recurrence off antiarrhythmics (vs. 14.5% in Group 2, P < 0.0001). At last follow-up, antiarrhythmics continued to be required for rhythm control in 40.1% and 46.2% of patients in Groups 1 and 2, respectively (P < 0.0001). The secondary endpoint was met in 60.2% versus 32.1% of patients in Groups 1 and 2, respectively (P < 0.0001). In multivariable Cox analyses, repeat ablation was associated with significant reduction in arrhythmia recurrences compared to medical therapy alone (HR 0.48, 95% CI 0.35-0.65, P < 0.0001). CONCLUSION: In patients with recurrent symptomatic arrhythmia after ablation of PersAF, repeat ablation was associated with significant reduction in arrhythmia recurrences compared to routine medical therapy alone.

Dofetilide for suppression of atrial fibrillation in hypertrophic cardiomyopathy: A case series and literature review.

BACKGROUND: Limited medical options are available for rhythm control in patients with atrial fibrillation (AF) and hypertrophic cardiomyopathy (HCM). There are no published reports of dofetilide use in this population. METHODS: A retrospective chart review was conducted on 1,404 patients loaded on dofetilide for AF suppression at the Cleveland Clinic from 2008 to 2012, 25 of whom were found to have HCM. RESULTS: The HCM cohort was 32% female, 76% with persistent AF, mean age of 59 ± 10 years, and mean ejection fraction of 54 ± 9 %. Of the 25 patients, 21 were discharged on dofetilide, three discontinued during loading due to QTc prolongation, and one due to inefficacy. There were no adverse events during loading. Of those discharged on dofetilide, 11/21 (52%) were still on it at a median follow-up of 396 (198, 699) days at the time of the chart review. For those in whom it was discontinued, the median time on the drug was 301 (111, 738) days. Of the 10 patients who discontinued dofetilide during follow-up, six were due to inefficacy, one postablation, one postheart transplant, one due to death secondary to lung cancer, and one due to worsening edema. CONCLUSIONS: Dofetilide was well tolerated in this group of patients with AF and HCM and it facilitated management of AF in 21/25 (84%) patients. Further research is needed to assess the safety and efficacy of dofetilide in order to develop evidence-based guidelines for the pharmacological management of AF in this population.

Persistent Atrial Fibrillation Ablation With or Without Contact Force Sensing.

INTRODUCTION: Arrhythmia recurrences remain common after ablation of persistent atrial fibrillation (PersAF). Contact force (CF)-sensing catheters have been introduced for objective assessment of contact during radiofrequency application and have been suggested to improve outcomes in ablation of paroxysmal AF, but little is known about their role in PersAF ablation. We aimed to compare the procedural profiles and outcomes of (PersAF) ablation with or without using CF-sensing catheters. METHODS: All consecutive patients undergoing first time ablation for PersAF between April 2014 and January 2015 at the Cleveland Clinic were included. Substrate modification was performed in addition to isolation of the pulmonary veins. Success rates were determined off antiarrhythmics over 1 year of follow-up. RESULTS: The study included 174 patients (77 CF and 97 non-CF). Ablation with CF-sensing catheters resulted in shorter procedures (median 204 vs. 216 minutes, P = 0.04) and shorter fluoroscopy time (36 vs. 48 minutes, P = 0.0005), without statistical difference in radiation dose (225 vs. 270 milligrays, P = 0.1). Arrhythmia recurrences were less likely to be observed in the CF-sensing group (27.6% vs. 46.4%, P = 0.01, log-rank P = 0.004). In multivariable Cox analyses, the use of CF-sensing catheters was associated with a lower risk of arrhythmia recurrence (hazard ratio 0.49, 95% confidence interval 0.27-0.85, P = 0.01). CONCLUSIONS: Compared to non-CF sensing, the use of CF-sensing catheters for PersAF ablation is associated with shorter procedures, shorter fluoroscopy time, and reduction in arrhythmia recurrences.

Care delivery and self management strategies for adults with epilepsy.

BACKGROUND: Researchers have criticised epilepsy care for adults for its lack of impact, stimulating the development of various service models and strategies to respond to perceived inadequacies. OBJECTIVES: To assess the effects of any specialised or dedicated intervention beyond that of usual care in adults with epilepsy. SEARCH METHODS: For the latest update of this review, we searched the Cochrane Epilepsy Group Specialized Register (9 December 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 11), MEDLINE (1946 to June 2013), EMBASE (1988 to June 2013), PsycINFO (1887 to December 2013) and CINAHL (1937 to December 2013). In addition, we contacted experts in the field to seek information on unpublished and ongoing studies, checked the websites of epilepsy organisations and checked the reference lists of included studies. SELECTION CRITERIA: We included randomised controlled trials, controlled or matched trials, cohort studies or other prospective studies with a control group, and time series studies. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted all data, and assessed the quality of all included studies. MAIN RESULTS: Our review included 18 different studies of 16 separate interventions, which we classified into seven distinct groups. Most of the studies have methodological weaknesses, and many results from other analyses within studies need to be interpreted with caution because of study limitations. Consequently, there is currently limited evidence for the effectiveness of interventions to improve the health and quality of life in people with epilepsy. It was not possible to combine study results in a meta-analysis because of the heterogeneity of outcomes, study populations, interventions and time scales across the studies. AUTHORS' CONCLUSIONS: Two intervention types, the specialist epilepsy nurse and self management education, have some evidence of benefit. However, we did not find clear evidence that other service models substantially improve outcomes for adults with epilepsy. It is also possible that benefits are situation specific and may not apply to other settings. These studies included only a small number of service providers whose individual competence or expertise may have had a significant impact on outcomes. At present it is not possible to advocate any single model of service provision.

Association Between Off-site Central Monitoring Using Standardized Cardiac Telemetry and Clinical Outcomes Among Non-Critically Ill Patients.

IMPORTANCE: Telemetry alarms involving traditional on-site monitoring rarely alter management and often miss serious events, sometimes resulting in death. Poor patient selection contributes to a high alarm volume with low clinical yield. OBJECTIVE: To evaluate outcomes associated with an off-site central monitoring unit (CMU) applying standardized cardiac telemetry indications using electronic order entry. DESIGN, SETTING, AND PARTICIPANTS: All non-intensive care unit (ICU) patients at Cleveland Clinic and 3 regional hospitals over 13 months between March 4, 2014, and April 4, 2015. EXPOSURES: An off-site CMU applied standardized cardiac telemetry when ordered for standard indications, such as for known or suspected tachyarrhythmias or bradyarrhythmias. MAIN OUTCOMES AND MEASURES: CMU detection and notification of rhythm/rate alarms occurring 1 hour or less prior to emergency response team (ERT) activation, direct CMU-to-ERT notification outcomes, total telemetry census, and cardiopulmonary arrests in comparison with the previous 13 months. RESULTS: The CMU received electronic telemetry orders for 99,048 patients (main campus, 72,199 [73%]) and provided 410,534 notifications (48% arrhythmia/hemodynamic) among 61 nursing units. ERT activation occurred among 3243 patients, including 979 patients (30%) with rhythm/rate changes occurring 1 hour or less prior to the ERT activation. The CMU detected and provided accurate notification for 772 (79%) of those events. In addition, the CMU provided discretionary direct ERT notification for 105 patients (ventricular tachycardia, n = 44; pause/asystole, n = 36; polymorphic ventricular tachycardia/ventricular fibrillation, n = 14; other, n = 11), including advance warning of 27 cardiopulmonary arrest events (26%) for which return of circulation was achieved in 25 patients (93%). Telemetry standardization was associated with a mean 15.5% weekly census reduction in the number of non-ICU monitored patients per week when compared with the prior 13-month period (580 vs 670 patients; mean difference, -90 patients [95% CI, -82 to -99]; P < .001). The number of cardiopulmonary arrests was 126 in the 13 months preintervention and 122 postintervention. CONCLUSIONS AND RELEVANCE: Among non-critically ill patients, use of standardized cardiac telemetry with an off-site central monitoring unit was associated with detection and notification of cardiac rhythm and rate changes within 1 hour prior to the majority of ERT activations, and also with a reduction in the census of monitored patients, without an increase in cardiopulmonary arrest events.

Radiofrequency Ablation with an Enhanced-Irrigation Flexible-Tip Catheter versus a Standard-Irrigation Rigid-Tip Catheter.

BACKGROUND: The flexible-tip irrigated ablation catheter Cool Flex™ (St. Jude Medical, St. Paul, MN, USA) was introduced to enhance cooling of the catheter-tissue interface and to conform to endocardial surface with better contact. Little is known about the performance of such catheter design compared to the widely used rigid-tip catheters. METHODS: In a thigh muscle preparation, ablation using the flexible-tip and rigid-tip catheters was performed in seven pigs across a range of ablation settings and catheter orientation. Postprocedure, the thigh muscle was stained with 2,3,5-triphenyltetrazolium-chloride injected into the femoral artery. The muscle was excised, fixed with formalin, and examined grossly. RESULTS: A total of 196 lesions (95 flexible tip, 101 rigid tip) were evaluated. The flexible-tip catheter was associated with enhanced cooling of catheter-tissue interface (31.1 ± 3.3°C vs 36.3 ± 3.7°C, P = 0.0001) in both perpendicular and nonperpendicular catheter orientations. This allowed more energy delivery (37.3 ± 8.9 W vs 33.7 ± 8.1 W, P = 0.004) to targeted tissue and resulted in larger lesions (median 194.7 [interquartile range: 113.1-333.8] mm(3) vs 170.9 [88.7-261.6] mm(3) , P = 0.03) than the rigid-tip catheter with larger maximum diameter (11.1 ± 2.6 mm vs 10.3 ± 2.1 mm, P = 0.03) and larger diameter at tissue surface (10.3 ± 2.4 mm vs 9.6 ± 1.7 mm, P = 0.01). Catheter orientation during ablation affected the efficiency of rigid-tip but not the flexible-tip catheter. The use of the flexible-tip catheter was associated with significantly less char formation on tissue (none vs 5.1% with rigid tip, P = 0.009). CONCLUSION: The Cool Flex™ catheter performed better than a rigid-tip catheter with enhanced cooling, larger ablation lesions, and no charring of targeted tissue.

Care delivery and self management strategies for children with epilepsy.

BACKGROUND: Epilepsy care for children has been criticised for its lack of impact. Various service models and strategies have been developed in response to perceived inadequacies in care provision for children and their families. OBJECTIVES: To compare the effectiveness of any specialised or dedicated intervention for the care of children with epilepsy and their families to the effectiveness of usual care. SEARCH METHODS: We searched the Cochrane Epilepsy Group Specialized Register (9 December 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2013,Issue 11), MEDLINE (1946 to June week 2, 2013), EMBASE (1988 to week 25, 2013), PsycINFO (1887 to 11 December 2013) and CINAHL Plus (1937 to 11 December 2013). In addition, we contacted experts in the field to seek information on unpublished and ongoing studies, checked the websites of epilepsy organisations and checked the reference lists of included studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs), controlled or matched trials, cohort studies or other prospective studies with a control group (controlled before-and-after studies), or time series studies. DATA COLLECTION AND ANALYSIS: Each review author independently selected studies, extracted data and assessed the quality of included studies. MAIN RESULTS: We included five interventions reported in seven study reports (of which only four studies of three interventions were designed as RCTs) in this review. They reported on different education and counselling programmes for children, children and parents, teenagers and parents, or children, adolescents and their parents. Each programme showed some benefits for the well-being of children with epilepsy, but each study had methodological flaws (e.g. in one of the studies designed as an RCT, randomisation failed) and no single programme was independently evaluated by more than one study. AUTHORS' CONCLUSIONS: While each of the programmes in this review showed some benefit to children with epilepsy, their impacts were extremely variable. No programme showed benefits across the full range of outcomes. No study appeared to have demonstrated any detrimental effects but the evidence in favour of any single programme was insufficient to make it possible to recommend one programme rather than another. More studies, carried out by independent research teams, are needed.

ACCF/AHA/ASE/ASNC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2013 multimodality appropriate use criteria for the detection and risk assessment of stable ischemic heart disease: a report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Failure Society of America, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

The American College of Cardiology Foundation along with key specialty and subspecialty societies, conducted an appropriate use review of common clinical presentations for stable ischemic heart disease (SIHD) to consider use of stress testing and anatomic diagnostic procedures. This document reflects an updating of the prior Appropriate Use Criteria (AUC) published for radionuclide imaging (RNI), stress echocardiography (Echo), calcium scoring, coronary computed tomography angiography (CCTA), stress cardiac magnetic resonance (CMR), and invasive coronary angiography for SIHD. This is in keeping with the commitment to revise and refine the AUC on a frequent basis. A major innovation in this document is the rating of tests side by side for the same indication. The side-by-side rating removes any concerns about differences in indication or interpretation stemming from prior use of separate documents for each test. However, the ratings were explicitly not competitive rankings due to the limited availability of comparative evidence, patient variability, and range of capabilities available in any given local setting. The indications for this review are limited to the detection and risk assessment of SIHD and were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Eighty clinical scenarios were developed by a writing committee and scored by a separate rating panel on a scale of 1-9, to designate Appropriate, May Be Appropriate, or Rarely Appropriate use following a modified Delphi process following the recently updated AUC development methodology. The use of some modalities of testing in the initial evaluation of patients with symptoms representing ischemic equivalents, newly diagnosed heart failure, arrhythmias, and syncope was generally found to be Appropriate or May Be Appropriate, except in cases where low pre-test probability or low risk limited the benefit of most testing except exercise electrocardiogram (ECG). Testing for the evaluation of new or worsening symptoms following a prior test or procedure was found to be Appropriate. In addition, testing was found to be Appropriate or May Be Appropriate for patients within 90 days of an abnormal or uncertain prior result. Pre-operative testing was rated Appropriate or May Be Appropriate only for patients who had poor functional capacity and were undergoing vascular or intermediate risk surgery with 1 or more clinical risk factors or an organ transplant. The exercise ECG was suggested as an Appropriate test for cardiac rehabilitation clearance or for exercise prescription purposes. Testing in asymptomatic patients was generally found to be Rarely Appropriate, except for calcium scoring and exercise testing in intermediate and high-risk individuals and either stress or anatomic imaging in higher-risk individuals, which were all rated as May Be Appropriate. All modalities of follow-up testing after a prior test or percutaneous coronary intervention (PCI) within 2 years and within 5 years after coronary artery bypass graft (CABG) in the absence of new symptoms were rated Rarely Appropriate. Pre-operative testing for patients with good functional capacity, prior normal testing within 1 year, or prior to low-risk surgery also were found to be Rarely Appropriate. Imaging for an exercise prescription or prior to the initiation of cardiac rehabilitation was Rarely Appropriate except for cardiac rehabilitation clearance for heart failure patients.

Left ventricular hypertrophy and antiarrhythmic drugs in atrial fibrillation: impact on mortality.

BACKGROUND: Despite sparse clinical data, current atrial fibrillation (AF) guidelines favor amiodarone as a drug of choice for patients with left ventricular hypertrophy (LVH). OBJECTIVE: This study tested the hypothesis that patients with persistent AF and LVH on nonamiodarone antiarrhythmics have higher mortality compared to patients on amiodarone. METHODS: In an observational cohort analysis of patients who underwent cardioversion for AF, patients with LVH, defined as left ventricular wall thickness ≥1.4 cm, by echocardiogram prior to their first cardioversion, were included; clinical data, including antiarrhythmic drugs and ejection fraction (LVEF), were collected. Mortality, determined via the Social Security Death Index, was analyzed using Kaplan-Meier and Cox proportional hazards models to determine whether antiarrhythmic drugs were associated with higher mortality. RESULTS: In 3,926 patients, echocardiographic wall thickness was available in 1,399 (age 66.8 ± 11.8 years, 67% male, LVEF 46 ± 15%, septum 1.3 ± 0.4, posterior wall 1.2 ± 0.2 cm), and 537 (38%) had LVH ≥1.4 cm. Among 537 patients with LVH, mean age was 67.5 ± 11.7 years, 76.4% were males, and mean LVEF was 48.3 ± 13.3%. Amiodarone was associated with lower survival (log rank P = 0.001), including after adjusting for age, LVEF, and coronary artery disease (P = 0.023). In propensity-score matched cohorts with LVH treated with no drugs, nonamiodarone antiarrhythmic drugs (non-AADs), or amiodarone (N = 65 each group), there was early lower survival in patients on amiodarone (P = 0.05). CONCLUSIONS: Patients with persistent AF and LVH on non-AADs do not have higher mortality compared to patients on amiodarone. Importantly, these findings do not support amiodarone as a superior choice in patients with LVH.

Appropriateness of implantable cardioverter-defibrillator device implants in the United States.

BACKGROUND: The appropriate use criteria (AUCs) are a diverse group of indications aimed to better evaluate the benefits of implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy. OBJECTIVE: The purpose of this study was to quantify the proportion of ICD and cardiac resynchronization therapy with defibrillator (CRT-D) implants as appropriate, may be appropriate (MA), or rarely appropriate (RA) on the basis of the AUC guidelines. METHODS: This is a multicenter retrospective study of patients within the National Cardiovascular Data Registry undergoing ICD implantation between April 2018 and March 2019 at >1500 US hospitals. The appropriateness of ICD implants was adjudicated using the AUC. RESULTS: Of 309,318 ICDs, 241,438 were primary prevention implants (78.1%) and 67,880 secondary prevention implants (21.9%); 243,532 (79%) were mappable to the AUC. For primary prevention, 185,431 ICDs (96.4%) were appropriate, 5660 (2.9%) MA, and 1205 (0.6%) RA. For secondary prevention, 47,498 ICDs (92.7%) were appropriate, 2581 (5%) MA, and 1157 (2.3%) RA. A significant number of RA devices were implanted in patients with New York Heart Association class IV heart failure who were ineligible for advanced therapies (53.9%) and those with myocardial infarction within 40 days (18.1%). The appropriateness of the pacing lead was more variable, with 48,470 dual-chamber ICD implants (62%) being classified as appropriate, 29,209 (37.4%) MA, and 448 (0.6%) RA. Among CRT-D implants, 63,848 (82.2%) were appropriate, 9900 (12.7%) MA, and 3940 (5.1%) RA for left ventricular pacing. A total of 99,754 implants were deemed appropriate but excluded from Centers for Medicare & Medicaid Services National Coverage Determination. More than 92% of hospitals had an RA implant rate of <4%. CONCLUSION: In this large national registry, 95% of mappable ICD and CRT-D implants were considered appropriate, with <2% of RA implants. Nearly 100,000 appropriate implants are excluded by Centers for Medicare & Medicaid Services National Coverage Determination.

Spontaneous dissociated firing from the pulmonary veins during ablation of paroxysmal atrial fibrillation: implications and impact on arrhythmia-free survival.

BACKGROUND: Following pulmonary vein isolation (PVI) for the treatment of paroxysmal atrial fibrillation (AF), spontaneous dissociated firing (DiFi) from the isolated veins may be observed. Little is known about the significance and prognostic implications of this phenomenon. We sought to determine the relationship between DiFi and ablation outcomes. METHODS: The study population consisted of 156 paroxysmal AF patients who underwent first time PVI and were found to have spontaneous DiFi from the pulmonary veins (PVs). Their outcomes were compared to a population of 156 propensity-matched controls from our prospectively maintained AF ablation data registry. RESULTS: DiFi was most frequently observed from the right superior PV and occurred in 89 patients (57.1%). After 24 months of follow-up, patients with DiFi had better success rates compared to those with silent veins after isolation (88.5% vs 75%, P = 0.002). The overall distribution of types of recurrent arrhythmia was similar between DiFi patients and their matched controls (P = NS). During repeat ablations, DiFi patients were less likely to have PV conduction recovery (60% vs 93.3%, P = 0.02). Importantly, none of the veins with DiFi during index procedures was found to have conduction recovery. CONCLUSION: In patients with paroxysmal AF undergoing ablation, DiFi from the PVs after their isolation was associated with improved ablation outcomes. It is possible that DiFi is an indicator of successful durable isolation of the PVs. The findings suggest that confirmation of exit block may be warranted to improve AF ablation outcomes.

Exploring perceptions of psychological services in a children's hospice in the United Kingdom.

BACKGROUND: The provision of emotional and psychological support for all family members who need it is an essential element of holistic palliative care. Within East Anglia's Children's Hospice, teams of professionally trained and experienced workers offer psychosocial support to all family members at all times during the child's and family's journey. However, the effectiveness and appropriateness of current psychosocial provision is unclear, as is the requirement for any additional psychological services. OBJECTIVE: The purpose of this study was to elicit perceptions about current psychological support within the hospice from a group of stakeholders (parents, hospice staff, and external professionals). METHOD: Forty-five parents participated in family focus groups, telephone interviews, individual interviews in their home, or a web-based survey. Ninety-five hospice staff (including nurses, carers, play specialists, therapists, and family support practitioners) and 28 external staff (including physicians, nurses, and commissioning managers) were seen using a mixture of focus group and individual meetings. Focus groups and meetings were held at the hospice building or at an external venue. Interviews were recorded and transcribed verbatim and analyzed using thematic coding. RESULTS: Two main themes addressing perceptions of current psychological provision emerged: "understanding psychological support" and "unmet psychological need." Subthemes linked to support included choice, staff roles and labels, communication, and flexibility, whereas the themes within unmet need had a stronger focus on people and problems. SIGNIFICANCE OF RESULTS: Understanding different user perspectives is an important first step in enhancing current psychological provision; operationalizing the findings will be challenging.

Plasma B-type natriuretic peptide levels and recurrent arrhythmia after successful ablation of lone atrial fibrillation.

BACKGROUND: Plasma B-type natriuretic peptide (BNP) is abnormally elevated in patients with lone atrial fibrillation (AF). The exact significance and prognostic implications of this elevation have yet to be determined. Little is known about BNP in lone AF patients undergoing arrhythmia ablation. We sought to determine the relationship between BNP levels and the risk of recurrent arrhythmia after ablation of lone AF. METHODS AND RESULTS: We followed up 726 patients with lone AF undergoing first-time arrhythmia ablation. All had BNP levels measured on the day of ablation with of the point-of-care Triage Meter assay (Biosite Diagnostics, San Diego, CA). At baseline, factors associated with elevated BNP levels in multivariable linear regression analysis (with log BNP being the dependent variable) were older age (ß regression coefficient for +1-year change, 0.025; P<0.0001), longer duration of AF (ß for +1-year change, 0.031; P=0.01), nonparoxysmal AF (versus paroxysmal; ß, 0.52; P<0.0001), and larger left atrial size (ß for +1-cm(2) change, 0.040; P<0.0001). The BNP levels were strongly associated with arrhythmia recurrence in univariate- (hazard ratio for +1-log-BNP change, 2.32; 95% confidence interval, 2.11 to 2.74; P<0.001) and covariate- (hazard ratio for +1-log-BNP change, 2.13; 95% confidence interval, 2.06 to 2.38; P<0.001) adjusted Cox proportional hazards analysis. The covariate-adjusted hazard ratios for recurrent arrhythmia were 1.6, 2.7, 4.3, and 5.7 for the second, third, fourth, and fifth quintiles, respectively, compared with patients in the lowest quintile (P for trend across quintiles <0.001). CONCLUSIONS: B-type natriuretic peptide levels correlate with AF burden (chronicity, altered hemodynamics, and anatomic remodeling) in patients with lone AF and are strong predictors of recurrent arrhythmia after ablation. Elevated BNP levels may reflect increased cardiac chamber wall stress and/or intrinsic atrial disease, thus increasing the risk of arrhythmia recurrence.

Local Modal Regression.

A local modal estimation procedure is proposed for the regression function in a non-parametric regression model. A distinguishing characteristic of the proposed procedure is that it introduces an additional tuning parameter that is automatically selected using the observed data in order to achieve both robustness and efficiency of the resulting estimate. We demonstrate both theoretically and empirically that the resulting estimator is more efficient than the ordinary local polynomial regression estimator in the presence of outliers or heavy tail error distribution (such as t-distribution). Furthermore, we show that the proposed procedure is as asymptotically efficient as the local polynomial regression estimator when there are no outliers and the error distribution is a Gaussian distribution. We propose an EM type algorithm for the proposed estimation procedure. A Monte Carlo simulation study is conducted to examine the finite sample performance of the proposed method. The simulation results confirm the theoretical findings. The proposed methodology is further illustrated via an analysis of a real data example.