JAMA Internal Medicine: Atrial Fibrillation/Flutter Topic Collection

Trends in the Overuse of Ambulatory Health Care Services in the United States Overuse of Ambulatory Health Care Services

Kale MS, Bishop TF, Federman AD, et al. — Mon, 28 Jan 2013 00:00:00 GMT

Background

Given the rising costs of health care, policymakers are increasingly interested in identifying the inefficiencies in our health care system. The objective of this study was to determine whether the overuse and misuse of health care services in the ambulatory setting has decreased in the past decade.

Methods

Cross-sectional analysis of the 1999 and 2009 National Ambulatory Medical Care Survey and the outpatient department component of the National Hospital Ambulatory Medical Care Survey, which are nationally representative annual surveys of visits to non–federally funded ambulatory care practices. We applied 22 quality indicators using a combination of current quality measures and guideline recommendations. The main outcome measures were the rates of underuse, overuse, and misuse and their 95% CIs.

Results

We observed a statistically significant improvement in 6 of 9 underuse quality indicators. There was an improvement in the use of antithrombotic therapy for atrial fibrillation; the use of aspirin, β-blockers, and statins in coronary artery disease; the use of β-blockers in congestive heart failure; and the use of statins in diabetes mellitus. We observed an improvement in only 2 of 11 overuse quality indicators, 1 indicator became worse, and 8 did not change. There was a statistically significant decrease in the overuse of cervical cancer screening in visits for women older than 65 years and in the overuse of antibiotics in asthma exacerbations. However, there was an increase in the overuse of prostate cancer screening in men older than 74 years. Of the 2 misuse indicators, there was a decrease in the proportion of patients with a urinary tract infection who were prescribed an inappropriate antibiotic.

Conclusions

We found significant improvement in the delivery of underused care but more limited changes in the reduction of inappropriate care. With the high cost of health care, these results are concerning.

Discerning the Incidence of Symptomatic and Asymptomatic Episodes of Atrial Fibrillation Before and After Catheter Ablation (DISCERN AF) A Prospective, Multicenter Study Incidence of Symptomatic and Asymptomatic AF

Verma A, Champagne J, Sapp J, et al. — Mon, 28 Jan 2013 00:00:00 GMT

Background

The DISCERN AF study (Discerning Symptomatic and Asymptomatic Episodes Pre and Post Radiofrequency Ablation of Atrial Fibrillation) monitored atrial fibrillation (AF) using an implantable cardiac monitor (ICM) to assess the incidence and predictors of asymptomatic AF before and after catheter ablation.

Methods

Patients with symptomatic AF underwent implantation of an ICM with an automated AF detection algorithm 3 months before and 18 months after ablation. Patients kept a standardized diary to record symptoms of arrhythmia, and ICM data were downloaded every 3 months. All episodes were blindly adjudicated and correlated with the diary. Asymptomatic recurrences were ICM episodes of 2 minutes or longer with no associated diary symptoms.

Results

Fifty patients had 2355 ICM episodes. Of these, 69.0% were true AF/atrial flutter (AFL)/atrial tachycardia (AT); 16.0%, sinus with extrasystoles; 11.0%, artifact; and 4.0%, sinus arrhythmia. Total AF/AFL/AT burden was reduced by 86% from a mean (SD) of 2.0 (0.5) h/d per patient before to 0.3 (0.2) h/d per patient after ablation (P < .001), and 56.0% of all episodes were asymptomatic. The ratio of asymptomatic to symptomatic AF episodes increased after ablation from 1.1 to 3.7 (P = .002). By symptoms alone, 29 of 50 patients (58%) were free of AF/AFL/AT after ablation compared with 23 of 50 (46%) using ICM-detected AF/AFL/AT recurrence. Asymptomatic episodes were more likely AFL/AT and were significantly shorter and slower, with lower heart rate variability. However, the postablation state was the strongest independent predictor of asymptomatic AF.

Conclusions

The ratio of asymptomatic to symptomatic AF episodes increased from 1.1 before to 3.7 after ablation. Postablation state is the strongest predictor of asymptomatic AF. Symptoms alone underestimate postablation AF burden, with 12% of patients having asymptomatic recurrences only.

Trial Registration

clinicaltrials.gov Identifier: NCT00745706

Temporal Trends in Ischemic Stroke and Anticoagulation Therapy Among Medicare Patients With Atrial Fibrillation A 15-Year Perspective (1992-2007)

Shroff GR, Solid CA, Herzog CA. — Mon, 28 Jan 2013 00:00:00 GMT

Atrial fibrillation (AF) is an independent, modifiable risk factor for ischemic stroke and independently associated with increased mortality. Nonvalvular AF is associated with a nearly 5-fold higher risk of ischemic stroke; this risk progressively increases with age. In a meta-analysis involving 29 clinical studies and 28 044 patients, judicious antithrombotic therapy with adjusted-dose warfarin was shown to reduce risk related to ischemic stroke by nearly 60% and mortality by approximately 25%, without significant increases in hemorrhagic stroke. However, diffusion of evidence-based knowledge from clinical trials into routine clinical practice demonstrates a significant time lag and evidence-to-practice gap; rates of ischemic stroke are therefore higher in clinical practice. We sought to extend previous work by Lakshminarayan et al to examine temporal trends in ischemic and hemorrhagic stroke rates and warfarin use in the Medicare population over a span of 15 years.