Detection of atrial fibrillation in asymptomatic at-risk individuals.

BACKGROUND: Undiagnosed atrial fibrillation (AF) exposes unsuspecting patients to elevated stroke risks. The optimal algorithm for identifying patients who should be screened for AF remains undetermined. The objective of this study is to determine the AF burden in an asymptomatic, at-risk population. We also sought to investigate potential predictors of undiagnosed AF. METHODS: This registry is a prospective observational study assessing continuous ECG monitoring in screening for AF using a wearable single lead 7-day continuous monitoring device. Patients included were asymptomatic individuals, at risk for AF as determined by either 1) ≥65 years of age with ≥1 high risk factor or; 2) ≥75 years of age and ≥2 moderate risk factors. A multivariable logistic regression was used to explore the predictive value of certain patient characteristics in identifying patients susceptible to have undiagnosed AF. RESULTS: Among the 942 patients included, 25 patients (2.7%) had evidence of AF detected. Only 8 patients had AF duration ≥24 h. History of perioperative AF (OR: 3.25, 95%CI: 1.08-9.79, p = 0.036), age over 85 (OR: 4.71, 95%CI: 1.31-16.92, p = 0.017) and absence of cardiovascular disease (CVD) (OR: 0.27, 95%CI: 0.10-0.76, p = 0.013) were found to be predictive of undiagnosed AF. CONCLUSION: This study demonstrates the feasibility of office-based AF screening in at-risk population. The low rate of AF detection suggests that the optimal algorithm for identifying asymptomatic patients who would benefit from continuous screening remains unclear. Advanced age, history of perioperative AF and absence of CVD are variables that could be explored further.

Protecting worker and public health during responses to catastrophic disasters-learning from the World Trade Center experience.

Despite incremental lessons learned since 9/11, responder and community health remain at unnecessary risk during responses to catastrophic disasters, as evidenced during the BP Deepwater Horizon spill and Hurricanes Katrina, Rita, and Sandy. Much of the health harm that occurs during disaster response, as distinct from during the disaster event itself, is avoidable. Protection of public health should be an integral component of disaster response, which should "do no additional harm." This commentary examines how challenges and gaps the World Trade Center response resulted in preventable occupational and environmental health harm. It proposes changes in disaster response policies to better protect the health of rescue and recovery workers, volunteers, and impacted worker and residential communities.

Protecting disaster responder health: lessons (not yet?) learned.

Recent developments at the National Institute for Occupational Safety and Health (NIOSH), the Occupational Safety and Health Administration (OSHA), and the National Institute for Environmental Health Sciences (NIEHS) indicate that each of these agencies is wrestling with how to better protect the health of disaster workers. This article urges increased reliance on comprehensive exposure assessments, more protective exposure benchmarks, the precautionary principle, and the hierarchy of controls of hazards. Additional issues, such as methods and content of worker training, as well as enforcement of applicable standards, are also considered. Finally, an effort is made to clarify the goals of disaster response.

PCBs in schools: what about school maintenance workers?

Driven by environmental and parent activists, government agencies are paying increasing attention to the issue of PCBs in in-place caulk, particularly in school buildings. At the same time, there is insufficient consideration of the school maintenance workers and contractors who maintain and replace PCB caulk, even though they may constitute the school population with the highest exposures and risks. This commentary briefly assesses recent PCB-related developments at the U. S. Occupational Safety and Health Administration (OSHA), U. S. Environmental Protection Agency (EPA), and the New York State Education Department from an occupational health perspective.

"Protecting disaster site, support, and recovery workers"- a brief comment.

Jim Celenza (New Solutions, Vol. 18, No. 3) wrote of a lack of clarity as to whether OSHA's role in disaster response efforts is one of consultation or of enforcement. Here, the author suggests the problem originates not in a lack of clarity but rather in substantive policy changes implemented during the Bush administration. The revisions emphasize voluntary action at the expense of regulation and enforcement. The changes arguably are at variance with OSHA's legal obligation to ensure protection of workers against avoidable harmful exposures, including those that occur during disaster response efforts.

9/11 environmental health--disaster and response.

The tragic events of 9/11/01 and thereafter resulted in the worst environmental disaster in the history of New York City. Toxic contaminants were dispersed over a wide geographic area. A variety of exposure scenarios produced clinically diagnosed persistent respiratory and other illnesses in multiple exposure populations, with fatalities beginning to be reported. Government efforts to protect public health and to assess and remediate contaminants have been minimal and sometimes have been driven by political imperatives rather than by public health principles. This article examines the scope of the environmental disaster, the statutory requirements that regulate governmental response, and the nature of government response efforts. It provides the context for a companion article also published in this issue of New Solutions. The companion article examines a grassroots environmental movement, the World Trade Center Community Labor Coalition, and its advocacy efforts for environmental cleanup and for access to health care for impacted populations and communities.

Disaster response and grassroots environmental advocacy: the example of the World Trade Center Community Labor Coalition.

The tragic events of 9/11/01 and thereafter produced the worst environmental disaster in the history of New York City. Exposure to World Trade Center-derived toxic contaminants at Ground Zero and throughout Lower Manhattan has produced clinically diagnosed persistent respiratory and other illnesses in multiple exposure populations, with fatalities beginning to be reported. Government efforts to protect public health and to assess and remediate contaminants have been minimal. In response, a broad and sophisticated grassroots environmental movement has arisen in Lower Manhattan to push for environmental cleanup and for access to health care for impacted populations and communities. This movement unites community, labor, and environmental groups and continues to organize five years after 9/11. This article examines the development of grassroots response efforts, the work of the World Trade Center Community Labor Coalition, and obstacles encountered in coalition-building. Testimony of community and labor activists is provided in the appendix. The context for this article is provided by the companion article that precedes it in this issue of New Solutions. The preceding article examines the scope of the environmental disaster, the statutory requirements that regulate governmental response, and the nature of government response efforts.

The synthesis of mesoporous silicates containing bimetallic nanoparticles and magnetic properties of PtCo nanoparticles in silica.

Using a one-pot approach employing true liquid crystal templating on neutral surfactants and simple metal salt precursors, mesostructured, mesoporous silicates have been prepared in which bimetallic nanoparticles are deposited; magnetic properties of PtCo systems so prepared are evaluated.

Canadian Trial of Physiological Pacing: Effects of physiological pacing during long-term follow-up.

BACKGROUND: The Canadian Trial of Physiological Pacing (CTOPP) reported that the risk of stroke or cardiovascular death was similar between patients receiving ventricular versus physiological pacemakers at the end of the original follow-up period of 3 years. However, the occurrence of atrial fibrillation was significantly less frequent with physiological pacemakers. To assess a potential delayed benefit of physiological pacing, follow-up of patients in this study was extended to 6 years. METHODS AND RESULTS: A total of 1474 patients requiring a pacemaker for symptomatic bradycardia were randomized to receive ventricular and 1094 to physiological pacemakers. The primary outcome was stroke or cardiovascular death. The study was completed in July 1998, and follow-up was extended to July 2001. At a mean follow-up of 6.4 years, there was no difference between treatment groups in the primary outcome of cardiovascular death or stroke. There was no significant difference in total mortality or stroke between groups. There was a significantly lower rate of development of atrial fibrillation in the physiological group, with a relative risk reduction of 20.1% (CI, 5.4 to 32.5; P=0.009). CONCLUSIONS: The CTOPP extended study does not show a difference in cardiovascular death or stroke, or in total mortality, or in stroke between patients implanted with ventricular or physiological pacemakers over a mean follow-up of >6 years. However, there is a persistent significant reduction in the development of atrial fibrillation with physiological pacing.

Effect of an implantable cardioverter defibrillator with atrial detection and shock therapies on patient-perceived, health-related quality of life.

BACKGROUND: This study used a device (DDD implantable cardioverter defibrillator [ICD]) capable of delivering pacing and shock therapies to restore normal sinus rhythm in patients with atrial tachycardias or atrial fibrillation (AF). The purpose of this study was to assess the effect of the device on patient-perceived, health-related quality of life (QOL). METHODS: The DDD ICD was implanted in 267 patients with drug refractory, symptomatic AF from 45 centers across Europe, the United States, and Canada. Patients completed self-reported, validated QOL assessments at baseline and at 3- and 6-month follow-up visits (The Medical Outcomes Short Form 36 [SF-36] and the Symptom Checklist [SCL]). RESULTS: The mean age of the study group was 62 +/- 12 years, and 73% of the patients were male. A total of 150 patients completed SF-36 assessments, and 138 patients completed SCL assessments at all 3 times. Baseline scores were more impaired (P <.05) on most SF-36 scales compared with norms for a general population, but were similar to a comparison group of patients with AF who were referred to tertiary care centers. The role-physical, physical functioning, vitality, mental health, and social functioning scales all improved significantly with time (all P <.04). Similarly, symptom frequency and severity (SCL) also improved significantly from baseline to 6 months (both P <.01). Shock therapy was delivered in 86 of the 150 patients (57%) with complete SF-36 evaluations. There was no evidence that receiving shocks decreased the relative improvement in QOL associated with implantation of the device. CONCLUSIONS: In a 6-month period, QOL improves after implantation of a DDD ICD with atrial shock and pacing therapies. These improvements were not attenuated by receipt of shocks.

Effectiveness of implantable defibrillators for preventing arrhythmic events and death: a meta-analysis.

OBJECTIVES: The aim of this study was to compare the effectiveness of the implantable cardioverter defibrillator (ICD) and medical strategies for prevention of arrhythmic events and death. BACKGROUND: The ICD is a potential strategy to reduce mortality in patients at risk of sudden death. METHODS: The MEDLINE, EMBASE, and Cochrane Library electronic databases were searched from January 1966 to April 2002. All published randomized controlled trials comparing ICD implantation with medical therapy were reviewed. Four independent reviewers extracted data on all-cause mortality, nonarrhythmic death, and arrhythmic death using a standardized protocol. RESULTS: Nine studies including over 5,000 patients were synthesized using both fixed-effects and random-effects models. The primary and secondary prevention trials showed a significant benefit of the ICD with respect to arrhythmic death, with relative risks (RR) of 0.34 and 0.50, respectively (both p < 0.001). The mortality benefit of the ICD was entirely attributable to a reduction in arrhythmic death (all trials: p < 0.00001). Whereas the secondary prevention trials exhibited a robust decrease in all-cause ICD mortality (RR 0.75; p < 0.001), the pooled primary prevention trials demonstrated decreased all-cause ICD mortality (RR 0.66; p < 0.05) which was dependent on selected individual trials. The disparity in ICD-related mortality reductions in the primary prevention trials was related to variability in the incidence of arrhythmic death between individual studies. CONCLUSIONS: Although the ICD decreases the risk of arrhythmic death, its impact on all-cause mortality is related to the underlying risk of arrhythmia-related death relative to competing causes. Given the cost of the device strategy, policies of targeted intervention based on the future risk of arrhythmia are warranted.