Trends and outcomes in the hospitalization of older Americans for cardiac conduction disorders or arrhythmias, 1991-1998

The Role of Troponin Testing in Patients with Supraventricular Tachycardia, Systematic Review and Meta-Analysis

BACKGROUND

Supraventricular tachycardia (SVT) is commonly evaluated in the emergency department (ED). While troponin has been shown to be elevated in SVT, its usefulness for predicting coronary artery disease and future adverse cardiovascular outcomes has not been shown.

OBJECTIVES

We aimed to evaluate the prognostic utility of troponin measurement as part of SVT management in the ED.

METHODS

We performed a literature search in the PubMed and Scopus databases from inception to August 30, 2023, including all studies reporting troponin measurements in adult patients (age > 18 years) presenting to the ED with supraventricular tachycardia. The primary outcome of interest for this study was the prevalence of elevated troponin in patients with SVT. Secondary outcomes included the prevalence of major adverse cardiac events (MACE) and additional cardiac testing with significant findings.

RESULTS

We included 7 studies (500 patients) in our analysis. Six studies reported the number of patients with SVT and elevated troponin, with a pooled prevalence of 46% (95% CI 27-66%, I2 93%). The pooled prevalence of all MACE in our study was 6% (95% CI 1-25%), while the prevalence for MACE among patients with elevated serum troponin levels was 11% (95% CI 4-27%).

CONCLUSIONS

Troponin levels are frequently ordered for ED patients with SVT and are often elevated. However, this review suggests that they have low prognostic value in predicting MACE.

The association of racial differences with in-hospital outcomes of patients admitted for sinus node dysfunction

Background

The impact of race and its related social determinants of health on cardiovascular disease outcomes has been well documented. However, limited data exist regarding the association of race with in-hospital outcomes in patients admitted for sinus node dysfunction (SND).

Objective

To evaluate whether racial disparities exist in outcomes for patients hospitalized with a primary diagnosis of SND.

Methods

The National Inpatient Sample was queried from 2011 to 2018 for relevant ICD-9 and ICD-10 diagnosis and procedure codes. Baseline characteristics and in-hospital outcomes in patients with a primary diagnosis of SND were compared among White and non-White patients. A multivariate logistic regression model was used to adjust for potential confounding factors and statistically significant comorbidities between both cohorts.

Results

We identified 655,139 persons admitted with a primary diagnosis of SND, 520,926 (79.5%) of whom were White. Non-White patients had significantly higher all-cause mortality, length of stay, and total hospital cost. There were lower odds of pacemaker insertion (adjusted odds ratio [aOR] 1.13 [95% confidence interval (CI) 1.11–1.15]), temporary transvenous pacing (aOR 1.15 [95% CI 1.11–1.22]), and cardioversion (aOR 1.50 [95% CI 1.42–1.58]) in non-White patients. A subgroup analysis was performed and non-Hispanic Black race was predictive of a decreased odds of pacemaker insertion, cardioversion/defibrillation, and temporary transvenous pacing.

Conclusion

Significant differences of in-hospital outcomes exist between White and non-White patients with SND. These findings appeared to be primarily driven by disparities in non-Hispanic Black patients. Increased recognition and focused efforts to mitigate these disparities will improve the care of underrepresented populations treated for SND.

Atrial involvement and progression of sinus node dysfunction in non-senile patients: evidences from electroanatomic mapping and long-term follow-up

PURPOSE

Sinus node inability or conduction disorders of its surrounding atrial myocardium cause sinus node dysfunction (SND). This study aimed to characterize right atrium (RA) substrates and long-term atrial lead performance after pacemaker implantation in non-senile SND patients.

METHODS

Eighteen SND patients (53.3 ± 9.6 years) controlled by 18 age-matched supraventricular tachycardia patients were consecutively enrolled. The P-wave amplitude (PWA) and P-wave duration (PWD) were measured on surface electrocardiography. Electroanatomic mapping was conducted to assess the bipolar voltage, complex signals, volume, and activation time of RA. Pacemaker implantation was performed in SND patients after mapping.

RESULTS

Compared with controls, SND patients showed significant PWA reduction (0.13 ± 0.02 vs. 0.16 ± 0.04 mV, p = 0.017) and PWD prolongation (120.8 ± 15.2 vs. 105.2 ± 8.6 ms, p = 0.001). The RA endocardial voltage was lower (1.56 ± 0.78 vs. 2.57 ± 0.55 mV, p < 0.001) and activation time was longer (112.1 ± 14.9 vs. 90.8 ± 12.4 ms, p < 0.001) in the study group. Atrial lead was anchored at the lower atrial septum in one patient and failed in another due to extensive atrial scarring. During a median follow-up of 86 (57-88) months, one patient lost atrial capturing, and overall atrial sensing was significantly decreased (2.44 ± 1.16 vs. 1.87 ± 1.01 mV, p = 0.003).

CONCLUSIONS

Atrial involvement was proved and the process was progressive in non-senile SND patients, as demonstrated by diffused RA lower voltage, slower conduction, and the decrease of the atrial lead sensing.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Assessment of the Utility of Ordering a Troponin in Low- and Intermediate-Risk Patients Presenting to the Emergency Department with Supraventricular Tachycardia: A Retrospective Chart Review

BACKGROUND

A troponin assay is commonly sent for patients presenting to emergency departments (EDs) with supraventricular tachycardia (SVT). Multiple studies suggest that elevated troponin levels do not predict coronary artery disease in these patients. Patients with elevated troponins are more likely to have additional cardiac testing, which can lead to increased health care costs and unnecessary invasive procedures.

OBJECTIVE

Our objective was to evaluate low- to intermediate-risk patients (HEART [history, electrocardiography, age, risk factors and troponin] Score 1-6) presenting to the ED with SVT. Our hypothesis was that an elevated troponin would not predict major adverse cardiac events (MACE), but would be associated with increased hospital admission rates and lengths of stay.

METHODS

This was a retrospective cohort study of adult patients who presented with SVT to a large, urban, academic hospital ED over 4 years who had a troponin result. A total of 46 patients were included in the study.

RESULTS

Patients with a positive troponin (>0.05 ng/mL) had a hospital admission rate of 86% versus 21% for patients with negative troponin (p = 0.006); rate of cardiology consult of 86% versus 21% (p < 0.001); and a mean total length of stay of 4157 min versus 1347 min (p = 0.04). At 3 months, none of the patients with a positive troponin had an MACE, death from any cause, or positive results of cardiac testing.

CONCLUSIONS

Patients with a positive troponin result had significantly more admissions, cardiology consults, and longer hospital stays. These patients did not have an increased prevalence of MACE.

Evidence for reduced susceptibility to cardiac bradycardias in South Asians compared with Caucasians

Objectives

To investigate ethnic differences in susceptibility to bradycardias in South Asian and white European patients in the UK by determining rates of permanent pacemaker (PPM) implantation for sinus node dysfunction (SND) and atrioventricular block (AVB) in each ethnic group.

Methods

We carried out a retrospective cohort study into new PPM implantation during the period from 1 May 2006 to 31 March 2014, in patients of South Asian and Caucasian ethnicity resident in Leicestershire, UK. Numbers of individuals at risk in each ethnic group were derived from UK National Census data of 2011. Crude, and age-standardised incidence rates and risk ratios per 1000 population of PPM implantation were calculated for Caucasians and South Asians.

Results

During the study period, 4883 individuals from the Leicestershire population of 980 328 underwent PPM implantation, a cumulative implantation rate of 4.98/1000 population. The population cumulative PPM implantation rate for SND was 1.74/1000, AVB 2.83/1000 and other indications 0.38/1000 population. The crude incidence in Caucasians (6.15/1000 population) was higher than in South Asians (1.07/1000 population) and remained higher after age standardisation (5.60/1000 vs 2.03/1000, P<0.001). The age-standardised cumulative PPM implantation rates were lower in South Asians for both SND (0.53/1000 in South Asians; 1.97/1000 in Caucasians, P<0.001) and AVB (1.30/1000 in South Asians; 3.17/1000 in Caucasians, P<0.001). Standardised risk ratios (95% CI) for PPM implantation in South Asians compared with Caucasians for all pacing indications, SND and AVB were 0.36 (95% CI 0.36 to 0.37), 0.27 (95% CI 0.27 to 0.28) and 0.41 (95% CI 0.41 to 0.42), respectively.

Conclusions

Rates of PPM implantation are lower in South Asians residing in the UK, compared with Caucasians. This observation raises the possibility of lower inherent susceptibility to bradycardias in South Asians compared with Caucasians. Studies aimed at identifying underlying mechanisms, including possible genetic differences, are warranted.

Dosage Adjustments Related to Young or Old Age and Organ Impairment

Differences in physiology related to young or old age and/or organ system impairment alter the absorption, distribution, metabolism, and excretion of many medications and consequently their effectiveness and toxicity. This module discusses common alterations in medication use and dosage that are required in the pediatric age group, in the elderly, and in patients with renal or hepatic disease.

Cardiac Arrhythmias in a Septic ICU Population: A Review

Progressive cardiovascular deterioration plays a central role in the pathogenesis of multiple organ failure (MOF) caused by sepsis. Evidence of various cardiac arrhythmias in septic patients has been reported in many published studies. In the critically ill septic patients, compared to non-septic patients, new onset atrial fibrillation episodes are associated with high mortality rates and poor outcomes, amongst others being new episodes of stroke, heart failure and long vasopressor usage. The potential mechanisms of the development of new cardiac arrhythmias in sepsis are complex and poorly understood. Cardiac arrhythmias in critically ill septic patients are most likely to be an indicator of the severity of pre-existing critical illness.

Radiofrequency ablation changes the quality of life of children with supraventricular tachycardias

OBJECTIVE

Radiofrequency ablation (RFA) has rapidly become the first-line therapy for children with supraventricular tachycardia (SVT). Recently, more attention has been given to the measurement of health-related quality of life (QoL) in children. The primary aim of this study was to determine if there is a change in the QoL in children with SVT pre and post RFA procedure using the Pediatric Quality of Life Inventory (PedsQL) cardiac inventory. In addition, the study discusses the impact of age, gender and variety of SVT mechanisms on the QoL.

DESIGN, SETTING AND PATIENTS

All consecutive children with SVT referred for RFA at Mansoura University Children's Hospital were enrolled in this study. The PedsQL cardiac module questionnaire was given to the children/parents to be filled out before and 1 month following RFA procedure. Evaluated areas were physical, emotional, social, school and psychosocial function. The paired t test was used to test the difference between pre-time and post-time points for the study groups. Demographic and clinical data were collected.

RESULTS

The study sample consisted of 38 patients who underwent a successful ablation. The mean age of the patients at the time of RFA procedure was 12.4±5.3 years. There was a statistically significant improvement in all measured areas 1 month post successful RFA as compared with pre ablation. Post ablation, the greatest score improvement was in physical functioning. Older children (>12 years) showed the greatest benefit, but gender and type of SVT did not influence outcome.

CONCLUSIONS

RFA therapy is useful in improving QoL and perceptions in children with recurrent SVT.

Incidence of and risk factors for sick sinus syndrome in the general population

BACKGROUND

Little is known about the incidence of and risk factors for sick sinus syndrome (SSS), a common indication for pacemaker implantation.

OBJECTIVES

This study sought to describe the epidemiology of SSS.

METHODS

This analysis included 20,572 participants (mean baseline age 59 years, 43% male) in the ARIC (Atherosclerosis Risk In Communities) study and the CHS (Cardiovascular Health Study), who at baseline were free of prevalent atrial fibrillation and pacemaker therapy, had a heart rate of ≥ 50 beats/min unless using beta blockers, and were identified as of white or black race. Incident SSS cases were identified by hospital discharge International Classification of Disease-revision 9-Clinical Modification code 427.81 and validated by medical record review.

RESULTS

During an average 17 years of follow-up, 291 incident SSS cases were identified (unadjusted rate 0.8 per 1,000 person-years). Incidence increased with age (hazard ratio [HR]: 1.73; 95% confidence interval [CI]: 1.47 to 2.05 per 5-year increment), and blacks had a 41% lower risk of SSS than whites (HR: 0.59; 95% CI: 0.37 to 0.98). Incident SSS was associated with greater baseline body mass index, height, N-terminal pro-B-type natriuretic peptide, and cystatin C, with longer QRS interval, with lower heart rate, and with prevalent hypertension, right bundle branch block, and cardiovascular disease. We project that the annual number of new SSS cases in the United States will increase from 78,000 in 2012 to 172,000 in 2060.

CONCLUSIONS

Blacks have a lower risk of SSS than whites, and several cardiovascular risk factors were associated with incident SSS. With the aging of the population, the number of Americans with SSS will increase dramatically over the next 50 years.

Factors associated with the epidemic of hospitalizations due to atrial fibrillation

Recent reports have described that hospitalizations for atrial fibrillation (AF) are continuing to increase. Given that hospitalizations are responsible for most of the economic burden associated with AF, the aim of this study was to characterize the impact of age and how changing procedural practices may be contributing to the increasing rates of AF hospitalizations. The annual age- and gender-specific incidence of hospitalizations for AF, electrical cardioversions, electrophysiologic studies, and radiofrequency ablation procedures in Australia were determined from 1993 to 2007 inclusive. Over this 15-year follow-up period spanning almost 300 million person-years, a total of 473,501 hospitalizations for AF were identified. There was a relative increase in AF hospitalizations of 203% over the study period, in contrast to an increase for all hospitalizations of only 71%. Whereas the gender-specific incidence of hospitalizations remained stable, the age-specific incidence increased significantly over the study period, particularly in older age groups. AF hospitalizations associated with electrical cardioversions decreased from 27% to 14% over the study period. Electrophysiologic studies and radiofrequency ablation procedures contributed minimally to the overall increase in AF hospitalizations observed. In conclusion, in addition to the growing prevalence of AF because of the aging population, there is an increasing age-specific incidence of hospitalizations for AF, particularly in older age groups. In contrast, changing procedural trends have contributed minimally to the increasing number of AF-associated hospitalizations. Greater attention to older patients with AF is required to develop strategies to prevent hospitalizations and contain the growing burden on health care systems.

Association between KCNE1 (G38S) genetic polymorphism and non-valvular atrial fibrillation in an Uygur population

BACKGROUND

The relationship between KCNE1 G38S genetic polymorphism and non-valvular atrial fibrillation is different among different populations. The study explored the KCNE1 G38S to understand if the KCNE1 G38S is associated with the Uygur atrial fibrillation patients.

METHODS

KCNE1 G38S genetic polymorphism was determined between 237 non-valvular atrial fibrillation cases and 237 control subjects using PCR-RFLP.

RESULTS

In univariate analyses, there was a statistical difference in genotype distribution between the patients and controls, and a significant difference in allele frequency of KCNE1 G38S was observed between the two groups (62.6 vs 52.7 %, p = 0.003). In multivariate analyses, the KCNE1 38G variant was independently associated with a significant predisposing effect on AF after adjusting for related risk factors, and the odds ratio for patients was 1.634 (95 % CI: 1.192-2.240, p = 0.002).

CONCLUSION

The KCNE1 38G is a risk factor for incident AF in an Uygur population. The KCNE1 G38S might have different impact on AF in different ethnicities.

Treating critical supraventricular and ventricular arrhythmias

Atrial fibrillation (AF), atrial flutter, AV-nodal reentry tachycardia with rapid ventricular response, atrial ectopic tachycardia and preexcitation syndromes combined with AF or ventricular tachyarrhythmias (VTA) are typical arrhythmias in intensive care patients (pts). Most frequently, the diagnosis of the underlying arrhythmia is possible from the physical examination (PE), the response to maneuvers or drugs and the 12-lead surface electrocardiogram. In unstable hemodynamics, immediate DC-cardioversion is indicated. Conversion of AF to sinus rhythm (SR) is possible using antiarrhythmic drugs. Amiodarone has a conversion rate in AF of up to 80%. Ibutilide represents a class III antiarrhythmic agent that has been reported to have conversion rates of 50-70%. Acute therapy of atrial flutter (Aflut) in intensive care pts depends on the clinical presentation. Atrial flutter can most often be successfully cardioverted to SR with DC-energies <50 joules. Ibutilide trials showed efficacy rates of 38-76% for conversion of Aflut to SR compared to conversion rates of 5-13% when intravenous flecainide, propafenone or verapamil was administered. In addition, high dose (2 mg) of ibutilide was more effective than sotalol (1.5 mg/kg) in conversion of Aflut to SR (70 versus 19%). Drugs like procainamide, sotalol, amiodarone or magnesium were recommended for treatment of VTA in intensive care pts. However, only amiodarone is today the drug of choice in VTA pts and also highly effective even in pts with defibrillation-resistant out-of-hospital cardiac arrest (CA). There is a general agreement that bystander first aid, defibrillation and advanced life support is essential for neurologic outcome in pts after cardiac arrest due to VTA. Public access defibrillation in the hands of trained laypersons seems to be an ideal approach in the treatment of ventricular fibrillation (VF). The use of automatic external defibrillators (AEDs) by basic life support ambulance providers or first responder (FR) in early defibrillation programs has been associated with a significant increase in survival rates (SRs). However, use of AEDs at home cannot be recommended.

What can claims data tell the case manager?

PURPOSE OF STUDY

This article seeks to use claims data to evaluate provision of service in 4 diagnosis-related groups (DRGs) for a rural hospital in an effort to better understand an increasing length of stay (LOS) and a decreasing case mix index (CMI). The complexity of the patient drives the services delivered, but does it drive the DRG assignment? Reimbursement for inpatient medical services is driven by DRG assignment and has an associated expected LOS. LOS is a result of the combination of physician practice patterns, available services, and the medical complexity of the patient. Itemized hospital charges can provide sufficient information to examine service delivery in broad categories. When compared to the services delivered through a professional protocol, physician practice benchmarks can be created. Identifying those services that are consistent and inconsistent with the protocol can prove illuminating and point to under- and overutilization, inadequate documentation, as well as opportunities for physician education.

PRIMARY PRACTICE SETTING(S)

Although this study was undertaken using hospital inpatient claims, the study can be recreated in almost any practice setting where there is a consistent mechanism to capture the provision of services. In the broader scheme, as case management practice transitions from functional models to outcome models, the relevance of these issues becomes more profound. The information gleaned from such a study can not only benefit case management administrators but inform and impact those involved in case management at any level. Indeed, the information can illuminate practice patterns for those beyond the case management sector and can include financial administrators, physician practice managers, and physicians.

METHODOLOGY AND SAMPLE

A combination of developmental and casual-comparative methodology was applied to this study. The results of this study will create baselines for current practice patterns from which improvement opportunities in both resource and quality management can be identified. Casual-comparative research identifies a consequence and attempts to trace it back to its origin. In this case, the discharge diagnosis, a function of documentation, is the consequence, and this study attempts to determine whether physician practice patterns are accurately reflected in that documentation. The sample consisted of the itemized claims data for all patients discharged from Putnam Community Medical Center (PCMC) between January 1 and June 30, 2006, with a discharge DRG of 127, 089, 088, or 143. Records that did not have sufficient charges to map provision of care were excluded.

CONCLUSIONS

An analysis of the charges for the selected DRGs illustrates the actual care provided to the patient, rather than the resultant coding based on physician documentation. This finding leads to 1 of 3 conclusions: physician documentation is inadequate to allow accurate coding of services delivered; the physician may be ordering unnecessary services/interventions; or medical record coding may be suboptimal. The scope of today's acute care case management department often includes social work, utilization review, discharge planning, and resource management. Within that scope is the accountability for certain aspects of the hospital's financial performance, not the least of which is LOS. A clear understanding of the payer mix and the effect upon financial performance is necessary. Management of DRG reimbursement-based contracts requires investigation of practice patterns that may increase LOS, and documentation that can affect medical coding decisions. The results of these activities can guide clinical practice guideline adoption or development and identify opportunities to fine-tune documentation to better reflect services provided and support utilization decisions.

IMPLICATIONS FOR CASE MANAGEMENT PRACTICE

Case Management Society of America (CMSA) Standards of Practice charge the profession with engaging strategies whenever possible to improve outcomes. Performance indicators include advocacy, resource management/stewardship, and research utilization. Addressing physician practice patterns and reducing nonessential services are examples of advocacy at the service-delivery level. These activities are also examples of resource management/stewardship as they seek to "promote the most effective and efficient use of healthcare services and financial resources" (CMSA, 2002, p. 19). The standards of practice call for research utilization and encourage research activities that are appropriate to case management practice and the subsequent sharing of those findings. In this way, the profession is enriched and promotes cost-effective, quality care and case management practice.

U.S. emergency department visits for supraventricular tachycardia, 1993-2003

BACKGROUND

Supraventricular tachycardia (SVT) is often described as a recurrent condition that leads to emergency department (ED) visits. However, the epidemiology of ED visits for SVT is unknown.

OBJECTIVES

To define the frequency of SVT in U.S. EDs and to analyze patient characteristics, ED management, and disposition for such visits.

METHODS

The authors analyzed data from the National Hospital Ambulatory Medical Care Survey, 1993-2003. SVT cases were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification codes 426.7 or 427.0 in any of the three diagnostic fields.

RESULTS

Of the 1.1 billion ED visits over the 11-year study period, an estimated 555,000 (0.05%; 95% confidence interval [CI] = 0.04% to 0.06%) were related to SVT. The annual frequency and population rate appear stable between 1993 and 2003 (p for trend = 0.35). Compared with non-SVT visits, those with SVT were more likely to be older than 65 years of age (26% vs. 15%, p < 0.01) and female (70% vs. 53%, p < 0.01). Electrocardiograms were documented for most visits (91%; 95% CI = 85% to 96%). Approximately half of the patients (51%; 95% CI = 40% to 61%) received an atrioventricular nodal blocking medication, most frequently adenosine (26%; 95% CI = 17% to 36%). SVT visits ended in hospital admission for 24% (95% CI = 15% to 34%). At the other extreme, 44% (95% CI = 32% to 56%) were discharged without planned follow-up.

CONCLUSIONS

Supraventricular tachycardia accounts for approximately 50,000 ED visits each year. Higher visit rates in older adults and female patients are consistent with prior studies of SVT in the general population. This study provides an epidemiologic foundation that will enable future research to assess and improve clinical management strategies of SVT in the ED.

Supraventricular Dysrhythmias

Cardiovascular nursing practice includes accountability for the clinical and organizational processes to ensure positive outcomes for patients having cardiac dysrhythmias. For patients with supraventricular dysrhythmias, nurses have studied patient outcomes related to mortality, morbidity, quality of life, psychological and physical functioning, and symptoms. Nurses have also explored these same outcomes associated with the management of supraventricular dysrhythmias. In addition, nurses have contributed to understanding organizational outcomes such as healthcare utilization and costs associated with these patients. For patients with atrial fibrillation after cardiac surgery, nurses have studied patient and organizational outcomes related to mortality, morbidity, symptoms, psychological and physical functioning, and economic outcomes. This research has included numerous interdisciplinary studies, and most of it has been descriptive or observational in design. Areas for future nursing outcomes research, including more interventional studies, are discussed.

Assessing the direct costs of treating nonvalvular atrial fibrillation in the United States

OBJECTIVE

To determine the health-care resource use and costs attributable to treating atrial fibrillation (AF) in the United States.

METHODS

Retrospective analyses of three federally funded US databases (2001 data): 1) hospital inpatient stays (the Healthcare Cost and Utilization Project [HCUP]); 2) physician office visits (the National Ambulatory Medical Care Survey [NAMCS]); and 3) emergency department (ED) and hospital outpatient department visits (OPD) (the National Hospital Ambulatory Medical Care Survey [NHAMCS]). Identification of AF medical encounters was based on occurrence of AF-specific International Classification of Diseases (9th Edition)--Clinical Modification (ICD-9-CM) diagnosis code 427.31 (principal discharge diagnosis for inpatient setting; any diagnosis field for other settings). For the 10 most common principal discharge diagnoses in the inpatient setting, case-control comparison analyses were performed to estimate annual incremental costs of AF as a comorbid discharge diagnosis for hospital stays. Regression models were used to assess the impact of AF on hospitalization costs. Costs were estimated in year 2005 US dollars.

RESULTS

Approximately 350,000 hospitalizations, 5.0 million office visits, 276,000 ED visits, and 234,000 OPD were attributable to AF annually within the United States. Total annual costs for treatment of AF were estimated at $6.65 billion, including $2.93 billion (44%) for hospitalizations with a principal discharge diagnosis of AF, $1.95 billion (29%) for the incremental inpatient cost of AF as a comorbid diagnosis, $1.53 billion (23%) for outpatient treatment of AF, and $235 million (4%) for prescription drugs. In all regressions, AF was a significant contributor to hospital cost.

CONCLUSIONS

Treatment of AF represents a significant health-care burden with the costs of treating AF in the inpatient setting outweighing the costs of treating AF in the office, emergency room or hospital outpatient settings. Further research is needed to fully capture the costs of treating AF.

Spheres of clinical nurse specialist practice influence evidence-based care for patients with atrial fibrillation

PURPOSE

The purpose of this article is to review atrial fibrillation (AF) and its consequences, to present sources of published evidence-based guidelines for management of AF, and to highlight multifaceted clinical nurse specialist (CNS) interventions that promote positive outcomes for patients with AF.

RATIONALE

The number of people with AF is expected to increase from 2.3 million to more than 5 million in the next 50 years. AF is associated with increased mortality, morbidity, healthcare expenditures, and decreased quality of life. Recognition of the growing number of AF cases and adverse consequences of AF led to development of evidence-based guidelines for AF management. Although nurses in diverse settings are accountable for providing evidence-based care for patients with AF, the guidelines have not been widely disseminated to nurses.

DESCRIPTION

This discussion includes a review of the adverse consequences of AF and a summary of management of recently detected AF with a focus on recommendations for nursing activities/interventions that are supported by evidence-based guidelines. Multifaceted strategies directed toward nurses and nursing practice, patients/clients, and organizations/systems that are linked to published CNS competencies and outcomes are highlighted.

OUTCOMES

CNS influence in all 3 spheres of CNS practice promotes positive outcomes that include improved patient/client functioning and self-management, reduced complications of treatment, decreased fragmentation of care, advancement of professional nursing practice, adherence to regulatory standards, and development of patient care processes that are supported by published guidelines.

CONCLUSIONS

With the use of the strategies discussed, clinical nurse specialists, whose spheres of influence include nursing and nursing practice, patients/clients, and organizations/systems, promote improved patient outcomes through implementation of evidence-based guidelines for AF management.

Atrial fibrillation: public health implications

BACKGROUND

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in the United States, affecting 2.3 million Americans. AF is associated with significant morbidity, mortality, and poor quality of life. AF and its treatments result in high healthcare resource use and costs.

OBJECTIVE

To develop a framework for public health action for the prevention, detection, and control of AF.

METHODS

A literature search was conducted via MEDLINE and CINAHL for the 1990-2004 period. Key words included atrial fibrillation, epidemiology, prevention, detection, treatment, and public health.

RESULTS

Published data predict a substantial increase in the prevalence of AF due to improved survival of people with coronary heart disease; increasing prevalence of hypertension, heart failure, and diabetes; and the aging of the American population. Low public awareness of AF and quality-of-care issues related to detection, control, and management are evident.

CONCLUSIONS

Awareness, early detection and treatment, improved patient self-management, and attention by public health programs are essential to reduce the burden of AF. Partnerships among professional nursing and medical organizations, the Centers for Disease Control and Prevention, and patient advocacy groups represent another important approach to improving public health outcomes for AF. Hospitalizations for AF and controversies over optimal treatment strategies (e.g., rate vs rhythm control) underscore the need for both public health and applied research.

Supraventricular tachyarrhythmia as early indicator of a complicated course after esophagectomy

In a group of 89 consecutive patients with a standardized operative procedure, the incidence of supraventricular tachyarrhythmia (SVT), predisposing risk factors (preoperative and intraoperative factors and parameters of intensive care strategy) and therapeutic strategies were evaluated. Operative treatment consisted of transthoracic esophagectomy, gastric interposition and intrathoracic anastomosis. Overall hospital mortality was 6.7%. In 32 (37%) patients a new onset SVT occurred. Age and elevated body temperature were the only significant risk factor for SVT in the multivariate analysis, their odds ratios being 1.3 for each year above 58 and 5.6 for each degree above 37.8 degrees C, respectively. Secondary risk factors were history of hypertension and use of epinephrine, the corresponding odds ratios being 6.6 and 10.2. Digitalis (2/32) and calcium-antagonists (2/9) were unsatisfactory, while beta-blockers (13/20) and amiodarone (12/12) were efficient therapeutic agents. Incidence of SVT was significantly correlated with the development of postoperative septic complications.

Therapie bedrohlicher Herzrhythmusst�rungen

Tachyarrhythmias represent a frequent problem in intensive care medicine. However, considerable uncertainty prevails among physicians regarding optimal pharmacotherapy, due also to numerous negative study results on chronic antiarrhythmic therapy. Moreover, in an emergency situation, the physician faces the dilemma of treating a potentially life-threatening arrhythmia as quickly as possible while simultaneously ensuring adequate diagnostic work-up, which will be decisive for long-term therapy once the patient has survived the crisis. The differential diagnosis between supraventricular and ventricular tachycardias is primarily facilitated by knowledge of a few salient points from the patient's history and 12-lead electrocardiography. This overview presents the most important principles for treating these arrhythmias. Interventional therapy principles (overstimulation, ablation) play an increasing role in these considerations. New insights on the pathogenesis of "malignant" arrhythmias and implementation of new concepts such as defibrillation by lay responders with the automatic external defibrillator will substantially influence emergency treatment of tachyarrhythmias in the coming years.

Epidemiology of pacemaker procedures among Medicare enrollees in 1990, 1995, and 2000

Using Medicare hospital claims records and beneficiary enrollment data, the investigators describe the epidemiology of inpatient pacemaker procedures (International Classification of Diseases, Ninth Revision, Clinical Modification codes 37.80 to 37.89) in Medicare enrollees. From 1990 to 2000, the age-standardized inpatient pacemaker procedure prevalence (per 100,000 enrollees) increased from 325.4 to 504.4 in all Medicare beneficiaries. The prevalence increased significantly with age; was less for women than for men; and was less for blacks, Hispanics, and Asians than for whites.

Lifetime risk for development of atrial fibrillation: the Framingham Heart Study

BACKGROUND

Atrial fibrillation (AF) is the most common cardiac dysrhythmia and a source of considerable morbidity and mortality, but lifetime risk for AF has not been estimated.

METHODS AND RESULTS

We included all participants in the Framingham Heart Study who were free of AF at index ages of 40 years and older. We estimated lifetime risks for AF (including atrial flutter) to age 95 years, with death free of AF as a competing event. We followed 3999 men and 4726 women from 1968 to 1999 (176 166 person-years); 936 participants had development of AF and 2621 died without prior AF. At age 40 years, lifetime risks for AF were 26.0% (95% CI, 24.0% to 27.0%) for men and 23.0% (21.0% to 24.0%) for women. Lifetime risks did not change substantially with increasing index age despite decreasing remaining years of life because AF incidence rose rapidly with advancing age. At age 80 years, lifetime risks for AF were 22.7% (20.1% to 24.1%) in men and 21.6% (19.3% to 22.7%) in women. In further analyses, counting only those who had development of AF without prior or concurrent congestive heart failure or myocardial infarction, lifetime risks for AF were approximately 16%.

CONCLUSIONS

Lifetime risks for development of AF are 1 in 4 for men and women 40 years of age and older. Lifetime risks for AF are high (1 in 6), even in the absence of antecedent congestive heart failure or myocardial infarction. These substantial lifetime risks underscore the major public health burden posed by AF and the need for further investigation into predisposing conditions, preventive strategies, and more effective therapies.

Arrhythmias in the intensive care patient

PURPOSE OF REVIEW

Atrial fibrillation, atrial flutter, AV-nodal reentry tachycardia with rapid ventricular response, atrial ectopic tachycardia, and preexcitation syndromes combined with atrial fibrillation or ventricular tachyarrhythmias are typical arrhythmias in intensive care patients. Most frequently, the diagnosis of the underlying arrhythmia is possible from the physical examination, the response to maneuvers or drugs, and the 12-lead surface electrocardiogram. In all patients with unstable hemodynamics, immediate DC-cardioversion is indicated. Conversion of atrial fibrillation to sinus rhythm is possible using antiarrhythmic drugs. Amiodarone has a conversion rate in atrial fibrillation of up to 80%. However, caution in the use of short-term administration of intravenous amiodarone in critically ill patients with recent-onset atrial fibrillation is absolutely necessary, and the duration of therapy should not exceed 24 to 48 hours. Ibutilide represents a relatively new class III antiarrhythmic agent that has been reported to have conversion rates of 50% to 70%; it seems that ibutilide is even successful when intravenous amiodarone failed to convert atrial fibrillation.

RECENT FINDINGS

Newer studies compared the outcome of patients with atrial fibrillation and rhythm- or rate-control. Data from these studies (AFFIRM, RACE) clearly showed that rhythm control is not superior to rate control for the prevention of death and morbidity from cardiovascular causes. Therefore, rate-control may be an appropriate therapy in patients with recurrent atrial fibrillation after DC-cardioversion. Acute therapy of atrial flutter in intensive care patients depends on the clinical presentation. Atrial flutter can most often be successfully cardioverted to sinus rhythm with energies less than 50 joules. Ibutilide trials showed efficacy rates of 38-76% for conversion of atrial flutter to sinus rhythm compared with conversion rates of 5-13% when intravenous flecainide, propafenone, or verapamil was administered. In addition, a high dose (2 mg) of ibutilide was more effective than sotalol (1.5 mg/kg) in conversion of atrial flutter to sinus rhythm (70% versus 19%).

SUMMARY

There is general agreement that bystander first aid, defibrillation, and advanced life support is essential for neurologic outcome in patients after cardiac arrest due to ventricular tachyarrhythmias. The best survival rate from cardiac arrest can be achieved only when (1) recognition of early warning signs, (2) activation of the emergency medical services system, (3) basic cardiopulmonary resuscitation, (4) defibrillation, (5) management of the airway and ventilation, and (6) intravenous administration of medications occurs as rapidly as possible. Public access defibrillation, which places automatic external defibrillators in the hands of trained laypersons, seems to be an ideal approach in the treatment of ventricular fibrillation. The use of automatic external defibrillators by basic life support ambulance providers or first responder in early defibrillation programs has been associated with a significant increase in survival rates. Drugs such as lidocaine, procainamide, sotalol, amiodarone, or magnesium were recommended for treatment of ventricular tachyarrhythmias in intensive care patients. Amiodarone is a highly efficacious antiarrhythmic agent for many cardiac arrhythmias, ranging from atrial fibrillation to malignant ventricular tachyarrhythmias, and seems to be superior to other antiarrhythmic agents.

Increasing trends in hospitalization for atrial fibrillation in the United States, 1985 through 1999: implications for primary prevention

BACKGROUND

Atrial fibrillation, the most common sustained disturbance of heart rhythm, is associated with a 5-fold increase in the incidence of ischemic stroke.

METHODS AND RESULTS

The National Hospital Discharge Survey was used to estimate the annual number and prevalence of hospitalizations with atrial fibrillation among men and women 35 years of age or older. From 1985 through 1999, hospitalizations increased from 154 086 to 376 487 for a first-listed diagnosis and from 787 750 to 2 283 673 for any diagnosis. Prevalence was higher among successive age groups. Age-standardized prevalence was consistently higher among men than women. In 1999, essential hypertension, ischemic heart disease, congestive heart failure, and diabetes were prominent coexisting conditions. The number of male patients discharged home decreased from 77% to 63%, whereas the number of discharges to long-term care increased from 9% to 15%; the corresponding values for women were 72% to 56% and 15% to 23%. A slight increase in discharges to short-term care was indicated, whereas no trends were noted for in-hospital mortality.

CONCLUSIONS

Hospitalizations for atrial fibrillation have increased dramatically (2- to 3-fold) in recent years. The public health burden of atrial fibrillation is enormous and expected to continue to increase over the next decades. Primary prevention of atrial fibrillation must be recognized and pursued as a complementary management strategy for reducing cardiovascular morbidity and mortality.

Systematic screening of secondary diagnoses in Medicare administrative data to identify candidate risk factors for the principal diagnosis

PURPOSE

Secondary diagnoses in Medicare hospital discharge claims may include risk factors for the principal diagnosis. However, risk ratios for the principal diagnosis as a function of secondary diagnoses cannot be calculated because no comparable data exist for beneficiaries who are not hospitalized.

METHODS

Hospital discharge rates, as proxies for incidence rates, can be calculated by race and sex from Medicare claims and denominator files. If the prevalence of a risk factor is higher in one population group than another, that risk factor will be overrepresented among patients from the group at higher risk.

RESULTS

This imbalance is reflected in what is termed the odds difference, OD=[(r+r')/r][f(2)/(1- f(2))-f(1)/(1-f(1))], in which r is the background incidence rate, and r' is the additional risk conferred by a factor that is present in fractions f(1) and f(2) in the two groups. Unlike the risk ratio, the odds difference can be calculated from claims data. Given f(1) and f(2), the odds difference is directly proportional to the risk ratio, RR=(r+r')/r.

CONCLUSIONS

Ranking common secondary diagnoses by the magnitude of their odds difference between groups with disparate discharge rates for a given principal diagnosis may disclose secondary diagnoses that merit evaluation as candidate direct or indirect risk factors.

A theoretical model of the role of brain stem nuclei in alcohol-mediated arrhythmogenesis in older adults

Uncertainty about the mechanism of alcohol-mediated arrhythmogenesis and the effect of alcohol use on arrhythmic risk among older adults is an increasing concern in light of population aging and recent reports that moderate alcohol consumption may protect older adults against coronary artery disease. In this review, a theoretical model of the role of brain stem nuclei in alcohol-mediated arrhythmogenesis in older adults is developed. The model is based on the hypothesis that the effects of alcohol on central autonomic pathways of cardiac control may alter the threshold for alcohol-mediated arrhythmogenesis among older adults. Findings from multiple lines of research including cellular, electrophysiological, epidemiological, experimental, and clinical studies in human, animal, and in vitro models were synthesized in developing the model. Suggestions for future research on the topic of alcohol-mediated arrhythmogenesis in older adults are offered.