Management of atrial fibrillation in rheumatic valvular heart disease

Valvular Heart Disease Emergencies: A Comprehensive Review Focusing on the Initial Approach in the Emergency Department

Valvular heart disease (VHD) is an increasing health problem worldwide. Patients with VHD may experience several cardiovascular-related emergencies. The management of these patients is a challenge in the emergency department, especially when the previous heart condition is unknown. Specific recommendations for the initial management are currently poor. This integrative review proposes an evidence-based three-step approach from bedside VHD suspicion to the initial treatment of the emergencies. The first step is the suspicion of underlying valvular condition based on signs and symptoms. The second step comprises the attempt to confirm the diagnosis and assessment of VHD severity with complementary tests. Finally, the third step addresses the diagnosis and treatment options for heart failure, atrial fibrillation, valvular thrombosis, acute rheumatic fever, and infective endocarditis. In addition, several images of complementary tests and summary tables are provided for physician support.

Long-term outcomes of radiofrequency catheter ablation for atrial fibrillation in rheumatic heart disease patients with mild mitral stenosis

PURPOSE

To assess efficacy of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in rheumatic heart disease (RHD) patients with mild mitral stenosis (MS).

METHODS

This retrospective cohort study included 62 consecutive RHD patients with mild MS and AF and 124 AF patients without RHD with matched age, gender, AF types as control. Procedure endpoints were defined as circumferential pulmonary vein ablation (CPVA) for paroxysmal AF, CPVA plus bidirectional block of lines, and disappearance of complex fractionated atrial electrograms for non-paroxysmal patients in both groups.

RESULTS

Cumulative success rate during the total follow-up (RHD, 23-140 months; control, 24-140 months) was lower in RHD group than control (32.3 vs. 56.5%, log-rank P = 0.006). In RHD patients, the success rate was higher in paroxysmal AF patients than non-paroxysmal AF patients during the mid-term follow-up (55.0 vs. 26.2%, log-rank P = 0.041), and was similar between the two AF types during the total follow-up (45.0 vs. 26.2%, log-rank P = 0.130). Patients without mitral regurgitation (MR) or with mild MR had a higher success rate than patients with moderate MR during the total follow-up in both groups (45.0 vs. 9.1%, log-rank P = 0.014 in RHD group; 64.5 vs. 43.8%, log-rank P = 0.001 in control group).

CONCLUSIONS

The long-term outcome of RFCA for AF in RHD patients with mild MS was mediocre and worse than that for AF patients without RHD. The severity of MR was associated with RFCA outcome in both groups. In RHD patients with mild MS, a better prognosis of paroxysmal AF than non-paroxysmal AF was observed initially but turned similar over time.

Percutaneous Left Atrial Appendage Closure: is there a Role in Valvular Atrial Fibrillation

Atrial fibrillation, a chronic and highly morbid cardiovascular condition which affects over 33 million people worldwide, can be broadly categorized as valvular vs non-valvular in etiology. However, definitions of valvular atrial fibrillation have varied widely in the literature, and there is no clear consensus definition to date. Historically, patients with atrial fibrillation in the setting of rheumatic mitral valve disease have constituted a particularly high risk group for cardioembolic stroke, and for this reason many contemporary trials of pharmaceutical and device therapies for atrial fibrillation have systematically excluded patients with valvular heart disease. Therefore, vitamin K antagonism remains the favored approach to mitigate stroke risk in valvular atrial fibrillation, and the optimal strategy to treat atrial fibrillation patients with valvular heart disease who cannot tolerate oral anticoagulation therapy is unknown. Recent trials have demonstrated an important role for percutaneous left atrial appendage occlusion devices in patients with non-valvular atrial fibrillation, but the role of these devices in patients with valvular atrial fibrillation is uncertain. Given the worldwide burden of valvular atrial fibrillation, future trials intended to clarify the role of percutaneous left atrial appendage closure devices in valvular atrial fibrillation should provide important insight for the care of millions of patients.

Computational fluid dynamics modelling of left valvular heart diseases during atrial fibrillation

BACKGROUND

Although atrial fibrillation (AF), a common arrhythmia, frequently presents in patients with underlying valvular disease, its hemodynamic contributions are not fully understood. The present work aimed to computationally study how physical conditions imposed by pathologic valvular anatomy act on AF hemodynamics.

METHODS

We simulated AF with different severity grades of left-sided valvular diseases and compared the cardiovascular effects that they exert during AF, compared to lone AF. The fluid dynamics model used here has been recently validated for lone AF and relies on a lumped parameterization of the four heart chambers, together with the systemic and pulmonary circulation. The AF modelling involves: (i) irregular, uncorrelated and faster heart rate; (ii) atrial contractility dysfunction. Three different grades of severity (mild, moderate, severe) were analyzed for each of the four valvulopathies (AS, aortic stenosis, MS, mitral stenosis, AR, aortic regurgitation, MR, mitral regurgitation), by varying-through the valve opening angle-the valve area.

RESULTS

Regurgitation was hemodynamically more relevant than stenosis, as the latter led to inefficient cardiac flow, while the former introduced more drastic fluid dynamics variation. Moreover, mitral valvulopathies were more significant than aortic ones. In case of aortic valve diseases, proper mitral functioning damps out changes at atrial and pulmonary levels. In the case of mitral valvulopathy, the mitral valve lost its regulating capability, thus hemodynamic variations almost equally affected regions upstream and downstream of the valve. In particular, the present study revealed that both mitral and aortic regurgitation strongly affect hemodynamics, followed by mitral stenosis, while aortic stenosis has the least impact among the analyzed valvular diseases.

DISCUSSION

The proposed approach can provide new mechanistic insights as to which valvular pathologies merit more aggressive treatment of AF. Present findings, if clinically confirmed, hold the potential to impact AF management (e.g., adoption of a rhythm control strategy) in specific valvular diseases.

Combined percutaneous balloon mitral valvuloplasty and left atrial appendage occlusion device implantation for rheumatic mitral stenosis and atrial fibrillation

Rheumatic heart disease is a common cause of cardiovascular morbidity and mortality worldwide, mostly in developing countries. Mitral stenosis and atrial fibrillation often coexist, related to both structural and inflammatory changes of the mitral valve and left atrium. Both predispose to left atrial thrombus formation, commonly involving the left atrial appendage. Thromboembolism can occur, with devastating consequences. We report the case of a 62 year old woman with rheumatic heart disease resulting in mitral stenosis and atrial fibrillation. Previous treatment with warfarin resulted in life-threatening gastrointestinal bleeding and she refused further anticoagulant therapy. A combined procedure was performed, including percutaneous balloon mitral valvuloplasty and left atrial appendage occlusion device implantation with the Atritech® Watchman® device. No thromboembolic or bleeding complications were encountered at one year follow-up. Long-term follow-up in a cohort of patients will be required to evaluate the safety and efficacy of this strategy.

Secular trends in the etiology and comorbidity of hospitalized patients with congestive heart failure: A single-center retrospective study

Objective

To assess the secular trends in the etiology and comorbidity of patients hospitalized with congestive heart failure (CHF).

Methods

Data of 7,319 patients (mean age 59.6 years, 62.1% male) with a primary discharge diagnosis of CHF, hospitalized from January 1, 1993 to December 31, 2007 at the Chinese People's Liberation Army (PLA) General Hospital were extracted and analyzed. These patients were divided into three groups according to hospitalization period: 1993–1997 (n = 1623), 1998–2002 (n = 2444), and 2003–2007 (n = 3252). The etiological characteristics and comorbidities were assessed.

Results

Over the study period, the proportion of patients with ischemic heart disease (IHD) increased from 37.2% during the period 1993–1997 to 46.8% during the period 2003–2007, while that with valvular heart disease (VHD) decreased from 35.2% during the period 1993–1997 to 16.6% during the period 2003–2007 (both P < 0.05). Atrial fibrillation (AF) was the most common comorbidity of heart failure (23.2%, 23.0% and 20.6%, respectively, in the three periods). Compared to that of the period of 1993–1997 with that of, the proportion of patients with myocardial infarction, pneumonia, renal function impairment and hepatic cirrhosis of the period of 2003–2007 increased significantly (P < 0.05) and the proportion of patients with chronic obstructive pulmonary disease and atrial fibrillation decreased significantly (P < 0.05).

Conclusions

This study implies that IHD has became a more common etiology of CHF, while VHD has deceased as an etiology of CHF in Chinese patients during the last two decades.

Patient selection for ambulatory cardiac monitoring in the Indian healthcare environment

Cardiovascular disease (CVD) in India comprises the bulk of non-communicable diseases, resulting in 2 million deaths per year. The incidence of CVD in India is estimated to be up to four times higher than in other countries. Though the quantification of the prevalence of rhythm disorders in India is not available, it can be inferred to be proportionately high. Identification and treatment of arrhythmia is limited by several socioeconomic factors including low health insurance penetration, limited reimbursement and high out-of-pocket expenditures. Thus, there exists a need in India to (1) select an appropriate tool that is both high yielding and cost effective and (2) employ a suitable patient selection method. This paper focuses on these two aspects for cardiac arrhythmia diagnosis using ambulatory monitoring technology, while keeping in mind the dynamics of the Indian healthcare setting.

Incidence of acute rheumatic fever in New Zealand children and youth

AIM

  To estimate acute rheumatic fever (ARF) incidence rates for New Zealand children and youth by ethnicity, socioeconomic deprivation and region.

METHODS

  National hospital admissions with a principal diagnosis of ARF (ICD9_AM 390-392; ICD10-AM I00-I02) were obtained from routine statistics and stratified by age, ethnicity, socioeconomic deprivation index (NZDep2006) and District Health Board (DHB).

RESULTS

  The mean incidence rate for ARF in 2000-2009 peaked at 9 to 12 years of age. Incidence rates for children 5 to 14 years of age for Māori were 40.2 (95% confidence interval 36.8, 43.8), Pacific 81.2 (73.4, 89.6), non-Māori/Pacific 2.1 (1.6, 2.6) and all children 17.2 (16.1, 18.3) per 100 000. Māori and Pacific incidence rates increased by 79% and 73% in 1993-2009, while non-Māori/Pacific rates declined by 71%. Overall rates increased by 59%. In 2000-2009, Māori and Pacific children comprised 30% of children 5-14 years of age but accounted for 95% of new cases. Almost 90% of index cases of ARF were in the highest five deciles of socioeconomic deprivation and 70% were in the most deprived quintile. A child living in the most deprived decile has about one in 150 risk of being admitted to the hospital for ARF by 15 years of age. Ten DHBs containing 76% of the population 5 to 14 years of age accounted for 94% of index cases of ARF.

CONCLUSIONS

  ARF with its attendant rheumatic heart disease is an increasing public health issue for disadvantaged North Island communities with high concentrations of Māori and/or Pacific families.

Mortality and hospitalisation costs of rheumatic fever and rheumatic heart disease in New Zealand

AIMS

  To estimate the annual mortality and the cost of hospital admissions for acute rheumatic fever (ARF) and rheumatic heart disease (RHD) for New Zealand residents.

METHODS

  Hospital admissions in 2000-2009 with a principal diagnosis of ARF or RHD (ICD9_AM 390-398; ICD10-AM I00-I099) and deaths in 2000-2007 with RHD as the underlying cause were obtained from routine statistics. The cost of each admission was estimated by multiplying its diagnosis-related group (DRG) cost weight by the national price for financial year 2009/2010.

RESULTS

  There were on average 159 RHD deaths each year with a mean annual mortality rate of 4.4 per 100, 000 (95% confidence limit 4.2, 4.7). Age-adjusted mortality was five- to 10-fold higher for Māori and Pacific peoples than for non-Māori/Pacific. The mean age at RHD death (male/female) was 56.4/58.4 for Māori, 50.9/59.8 for Pacific and 78.2/80.6 for non-Māori, non-Pacific men and women. The average annual DRG-based cost of hospital admissions in 2000-2009 for ARF and RHD across all age groups was $12.0 million (95% confidence limit $11.1 million, $12.8 million). Heart valve surgery accounted for 28% of admissions and 71% of the cost. For children 5-14 years of age, valve surgery accounted for 7% of admissions and 27% of the cost. Two-thirds of the cost occurs after the age of 30.

CONCLUSIONS

  ARF and RHD comprise a burden of mortality and hospital cost concentrated largely in middle age. Māori and Pacific RHD mortality rates are substantially higher than those of non-Māori/Pacific.

The coexistence of multiple cardiovascular diseases is an independent predictor of the 30-day mortality of hospitalized patients with congestive heart failure: a study in Beijing

BACKGROUND

Congestive heart failure (CHF) has become a major clinical and public health challenge with the aging of the population in China. However, the effect of the coexistence of multiple cardiovascular diseases on the prognosis of hospitalized patients with CHF remains unclear. A comparative analysis was performed to explore the etiology and comorbidities of CHF and in-hospital mortality in patients with CHF.

HYPOTHESIS

The coexistence of multiple cardiovascular diseases is an independent predictor of the 30-day mortality of hospitalized patients with CHF.

METHODS

All 6949 patients (4344 males, 2605 females) in the database with a principal ICD-9-CM discharge diagnosis of CHF were identified and divided into 5 groups according to the number of comorbidities. Cox proportional hazards regression was used to examine the association between the number of comorbidities and in-hospital mortality in patients with CHF.

RESULTS

A single comorbidity was predominant in younger patients (18-39 years, P<0.001), whereas multiple comorbidities were predominant in the elderly (≥80 years, P<0.001). The most common single etiology was valvular heart disease, and the most common triple etiology was hypertension and diabetes mellitus complicated by coronary artery disease. Cox regression analysis showed a higher hospital mortality rate associated with an increased number of comorbidities (hazard ratio [HR] from 1.22 [95% CI: 0.89-1.68] to HR 3.49 [95% CI: 2.55-4.78], P<0.001).

CONCLUSIONS

This study demonstrates the coexistence of multiple cardiovascular diseases is an independent predictor of the 30-day mortality of hospitalized patients with CHF.

Clinical epidemiology of atrial fibrillation and related cerebrovascular events in the United States

BACKGROUND

Atrial fibrillation (AF) is an important, independent risk factor for stroke and is estimated to cause a 5-fold increase in ischemic stroke risk. The aim of this article is to describe the changing epidemiology of AF in the United States and to assess the implications for stroke prevention and treatment.

REVIEW SUMMARY

AF prevalence is increasing in the general population. This is likely due to the aging of the population, the improvements in coronary care and the rising prevalence of AF risk factors such as diabetes. Risk factors such as rheumatic heart disease and hypertension have decreased in prevalence over the past few decades. However, novel risk factors such as obesity and possibly the metabolic syndrome have been identified and these have the potential to further increase AF prevalence. The utilization of warfarin has improved and this is reflected in falling ischemic stroke rates in the AF population. There is evidence for an increased incidence of anticoagulant associated intraparenchymal hemorrhages during the 1990s.

CONCLUSIONS

Although the decline in stroke rates in AF is laudable, the rising prevalence of AF, the changing profile of risk factors, and the recent plateauing of warfarin use indicate that stroke in AF patients will continue to be a significant public health problem.

Characterization and comparison of Na+, K+ and Ca2+ currents between myocytes from human atrial right appendage and atrial septum

Atrial pacing to reduce paroxysmal atrial fibrillation recurrences is performed in right atrial appendage (RAA) traditionally. However, recent studies indicate that atrial septal (AS) pacing produces better outcomes than the RAA pacing. The underlying mechanisms for this difference remained unclear. One possible explanation for the superiority of AS pacing over RAA pacing is that the two different regions have distinct electrophysiological properties. The study was to explore whether there indeed exist regional differences of electrical activities between RAA and AS, using whole-cell patch clamp techniques. The results showed that RAA cells had longer action potential duration, more negative resting potential and greater amplitude of action potential, whereas AS cells had more rapid depolarizing velocity. The sodium current was significantly smaller in RAA cells, whereas the calcium current was markedly smaller in AS cells. The transient outward K(+) current was similar in both regions. The ultrarapid delayed rectifier K(+) current was greater in RAA than that in AS cells. The inward rectifier K(+) current was similar at potentials more negative to -60 mV in both regions. The results indicate that RAA and AS of patients with rheumatic heart disease possess distinct electrophysiological properties. These differences provided a rational explanation for the different efficacies in treating atrial fibrillation by atrial pacing in RAA and AS regions.

Management of atrial fibrillation

Atrial fibrillation is the most common sustained cardiac rhythm disorder, and confers a substantial mortality and morbidity from stroke, thromboembolism, heart failure, and impaired quality of life. With the increasingly elderly population in the developed world, as well as improvements in the management of myocardial infarction and heart failure, the prevalence of atrial fibrillation is increasing, resulting in a major public-health problem. This Review aims to provide an overview on the modern management of atrial fibrillation, with particular emphasis on pharmacological and non-pharmacological approaches. Irrespective of a rate-control or rhythm-control strategy, stroke prevention with appropriate thromboprophylaxis still remains central to the management of this common arrhythmia. Electrophysiological approaches could hold some promise for a curative approach in atrial fibrillation.