心房颤动总是"引发"心房颤动吗?

心房颤动(AF)是临床上常见的心律失常,心房重构和AF"引发"AF概念的提出是对AF病理生理机制研究的重大进展,但临床上有关AF的诸多问题并不能都用AF"引发"AF和单纯的心房电重构来解释,本文就AF"引发"AF这一问题结合有关文献作一综述.     

阵发性房颤随访情况和阵发性房颤进展的危险因素

目的 观察阵发性房颤的随访情况和分析阵发性房颤进展的危险因素。方法 对216例阵发性房颤患者进行随访,观察其主要结局（是否发生房颤进展）和临床事件（卒中、心力衰竭、再住院和出血事件）,再按是否房颤进展分为房颤进展组（n=87）和房颤未进展组（n=129）。采用巢式病例对照研究方法,进行单因素分析和多因素分析（采用多因素Logistic回归模型）,分析影响房颤进展的危险因素。结果 216例阵发性房颤患者经过3.45年（中位数）随访发生房颤进展者87例,其发生进展率为40.2%,年进展率为11.7%。房颤进展组脑卒中、心力衰竭、房颤相关的再住院发生率均显著高于房颤未进展组（分别17% vs. 6%,18% vs. 5%,37% vs. 17%, 分别P<0.05,P<0.01和P<0.01）;两组间病死率及出血发生率差异未达到显著水平。多因素分析显示,年龄(OR 1.082,95%CI 1.016-1.392,P<0.05)、左房内径>45 mm(OR 2.339,95%CI 1.445-3.785,P<0.05)、CHADS2评分>3分(OR 1.382,95%CI 1.081-1.987,P<0.05)以及超敏C反应蛋白（hs-CRP）水平(OR 1.124,95%CI 1.005-2.345,P<0.05 )是房颤进展的独立危险因素。结论 阵发性房颤进展的年发生率为11.6%。影响房颤进展的独立危险因素为年龄、左房内径、hs-CRP水平及CHADS2评分。     

Predictors of atrial fibrillation recurrence in patients with long-lasting atrial fibrillation

BACKGROUND:

Limited data are available on the predictors of atrial fibrillation (AF) recurrence in patients with chronic AF.

OBJECTIVES:

To evaluate potential clinical, echocardiographic and electrophysiological predictors of AF recurrence after internal cardioversion for long-lasting AF.

METHODS:

A total of 99 consecutive patients (63 men and 36 women, mean age 63.33±9.27 years) with long-standing AF (52.42±72.02 months) underwent internal cardioversion with a catheter that consisted of two defibrillating coils. Shocks were delivered according to a step-up protocol. Clinical follow-up and electrocardiographic recordings were performed on a monthly basis for a 12-month period or whenever patients experienced symptoms suggestive of recurrent AF.

RESULTS:

Ninety-three patients (93.94%) underwent a successful uncomplicated cardioversion, with a mean atrial defibrillation threshold of 10.69±6.76 J. Immediate reinitiation of AF was observed in 15 patients (15.78%) of whom a repeated cardioversion restored sinus rhythm in 13 cases. Early recurrence of AF (within one week) was observed in 12 of 93 patients (12.90%). At the end of the 12-month follow-up period, during which seven patients were lost, 42 of the 86 remaining patients (48.84%) were still in sinus rhythm. Multivariate regression analysis showed that left atrial diameter (OR 1.126, 95% CI 1.015 to 1.249; P=0.025) and mitral A wave velocity (OR 0.972, 95% CI 0.945 to 0.999; P=0.044) were significant and independent predictors of AF recurrence, whereas age, left ventricular ejection fraction and AF cycle length were not predictive of arrhythmia recurrence.

CONCLUSION:

The present study showed that the left atrial diameter and mitral A wave velocity are the only variables associated with AF recurrence after successful cardioversion.     

New-onset atrial fibrillation

Patients with new-onset atrial fibrillation are often hospitalized emergently. To determine whether this is necessary, the authors retrospectively reviewed the care of 97 consecutive patients with this illness. No reason for the atrial fibrillation in 43 patients could be identified. Hypertension, coronary artery disease, and valvular heart disease were the most commonly associated conditions; myocardial infarction occurred in one patient. In 82% of patients, atrial fibrillation reverted to normal sinus rhythm during hospitalization. Three patients needed emergent hospitalization irrespective of the presence of atrial fibrillation. In the remainder, admission was based solely on the diagnosis of new-onset atrial fibrillation. Ninety-eight per cent had an uncomplicated hospital course. It is concluded that hospitalization is not necessary for all patients with new-onset atrial fibrillation. Those in whom reversion to normal sinus rhythm occurs rapidly during digoxin therapy can be discharged. Where no major medical illness is evident patients can be admitted to a bed outside the intensive care unit until reversion to normal sinus rhythm or rate control is achieved. Received from the Department of Medicine, North Shore University Hospital, Manhasset, New York, and the Departments of Medicine and Pharmacology, Cornell University Medical College, New York, New York. Supported in part by a grant from the Pharmaceutical Manufacturers Association Foundation.     

Cardioversion in atrial fibrillation. Focus on recent-onset atrial fibrillation

Atrial fibrillation is the most common sustained arrhythmia encountered in clinical practice. Its prevalence is rising due to an increasing elderly population and the improvement in management of life-threatening diseases such as myocardial infarction and heart failure. Over the past few years effective non-pharmacological treatments, new antiarrhythmics drugs, and anticoagulants have been introduced. Regardless of rate-control or rhythm control strategy, adequate stroke prevention still remains a cornerstone in the treatment of this arrhythmia. This review aims to illustrate the main practical issues in the management of atrial fibrillation, focusing on patients with recent-onset and hemodynamically stable atrial fibrillation.     

Deglutition-induced atrial fibrillation

We present the case of 38-year-old woman who experienced palpitations on swallowing, which were later found to be atrial fibrillation. Her symptoms improved on treatment with disopyramide and verapamil. Within 9 months, she was weaned from both medications without recurrence of symptoms.     

Postoperative atrial fibrillation

Postoperative atrial fibrillation is associated with significant morbidity, longer hospital stay, and higher related costs. Although the etiologic mechanism of postoperative atrial fibrillation and its optimum method of prophylaxis or management are not well defined, progress has been made during the past decade. This review focused on recent findings leading to a better understanding of the mechanisms and management of atrial fibrillation after surgery and current approaches directed at prevention of thromboembolic sequelae. Because postoperative atrial fibrillation is a frequent complication, preoperative risk assessment algorithms are being proposed to minimize the number of patients in whom an intervention to prevent atrial fibrillation is undertaken, and thus, reduce toxicity due to antiarrhythmic drug therapy. Finally, current data suggest that once atrial fibrillation has occurred, a rate-control strategy during the first 8 to 12 hours is reasonable because 50% of those episodes will resolve during this period. Beyond this period, a more aggressive approach using class IC or III antiarrhythmic drugs will hopefully reduce the number of patients requiring anticoagulation and prolonged drug therapy.     

Drug-induced atrial fibrillation

Atrial fibrillation (AF) is the most common sustained rhythm disorder observed in clinical practice and predominantly associated with cardiovascular disorders such as coronary heart disease and hypertension. However, several classes of drugs may induce AF in patients without apparent heart disease or may precipitate the onset of AF in patients with preexisting heart disease. We reviewed the literature on drug-induced AF, using the PubMed/Medline and Micromedex databases and lateral references. Successively, we discuss the potential role in the onset of AF of cardiovascular drugs, respiratory system drugs, cytostatics, central nervous system drugs, genitourinary system drugs, and some miscellaneous agents. Drug-induced AF may play a role in only a minority of the patients presenting with AF. Nevertheless, it is important to recognize drugs or other agents as a potential cause, especially in the elderly, because increasing age is associated with multiple drug use and a high incidence of AF. This may contribute to timely diagnosis and management of drug-induced AF.     

Initiation of ventricular fibrillation by atrial fibrillation

We report the case of a patient who developed spontaneouslya ventricular fibrillation during atrial fibrillation, 8 minafter a perfusion of isoproterenol was stopped Two mechanismscould explain the ventricular arrhythmia: silent ischaemia anda long-short cycle sequence just before ventricular fibrillation.     

Ablation of atrial fibrillation

Atrial fibrillation (AF) is a common arrhythmia, affecting an estimated 2 million people in the United States and its prevalence increases with age, reaching 10% in those > or = 80 years. AF confers a four- to fivefold increased risk of stroke compared to the general population and has been associated with a doubling of all-cause mortality. During the past decade, limited success rates of drug treatment stimulated an exploration of interventional treatment options for AF. As our knowledge on initiating triggers and perpetuating substrate of AF expanded, different potentially curative catheter ablation techniques have been developed. In this article we review the current patient selection criteria, methods, and the results of the catheter ablation of atrial fibrillation.     

Epidemiology of atrial fibrillation

The incidence and prevalence of atrial fibrillation (AF) increase progressively with age, and approximately 50% of patients with AF are 75 years of age or older. Advanced age is also a potent risk factor for stroke in patients with AF, and the proportion of strokes attributable to AF increases exponentially with age. In addition, AF contributes incrementally to health care utilization and costs, and decrementally to survival and quality of life in older adults. Furthermore, the societal impact of AF will likely double over the next three decades due to the aging of the population. For these reasons, it is essential to develop more effective strategies for the prevention and treatment of AF in older individuals. This work was supported by a grant from the National Institute on Aging (R13 AG23743, Michael W. Rich, MD, PI)     

心房颤动的药物治疗

药物治疗是目前心房颤动(房颤)最主要的治疗方式.房颤导致血流动力学障碍的原因有两个,即节律紊乱和快速心室反应.针对这两个方面,药物治疗形成了两种策略,(1)节律控制策略,即转复并维持窦性心律,包括药物复律或电复律后以药物维持窦性心律;(2)频率控制策略,即控制心室率.两种策略各有优缺点.     

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.