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The management of patients with atrial fibrillation involves three main areas: anticoagulation, rate control and rhythm control. Importantly, these are not mutually exclusive of each other. Anticoagulation is necessary for patients who are at a high risk of stroke; for example, those who are older than 75 years, or those who have hypertension, severe left ventricular dysfunction, previous cerebrovascular events, or diabetes. It is now clear that patients who are at a high risk of stroke require long-term anticoagulation with warfarin regardless of whether a rate-control or rhythm-control strategy is chosen. One possible exception might be patients who are apparently cured with catheter ablation. Several published trials comparing rate-control and rhythm-control strategies for the treatment of patients with atrial fibrillation have shown no difference in mortality between these approaches. The patients enrolled in these studies were typically over 65 years of age. Data comparing rate and rhythm strategies in patients who are younger than 60 years of age are limited. For more elderly patients, it seems reasonable to consider rate control as a primary treatment option and to reserve rhythm control for those who do not respond to rate control. For younger patients, we prefer to start with a rhythm-control approach and to reserve rate-control approaches for patients in whom antiarrhythmic drugs, ablation, or both, do not ameliorate the symptoms.

Atrial fibrillation occurs commonly in the setting of congestive heart failure and, in fact can cause left ventricular dysfunction due to a rapid ventricular response over time, termed tachycardia-mediated cardiomyopathy. The combination of atrial fibrillation and congestive heart failure leads to a high risk of stroke for the patient and appropriate antithrombotic therapy can minimize this incidence of stroke. Stroke risk can be markedly reduced by treatment with warfarin and complications of anticoagulation minimized by close attention to maintaining the INR between 2.0 and 3.0.

To develop and validate a predictive model that would allow clinicians to determine whether an electrophysiologic (EP) study is likely to result in useful diagnostic information for a patient who has unexplained syncope.One hundred seventy-nine consecutive patients with unexplained syncope who underwent EP studies at two university medical centers comprised the training sample. A test sample to validate the model was made up of 138 patients from the clinical literature who had undergone EP studies for syncope.Retrospective analysis of patients undergoing EP studies for syncope. The data collector was blinded to the study hypothesis; the electrophysiologist assessing outcomes was blinded to clinical and historical data. Clinical predictor variables available from the history, the physical examination, electrocardiography (ECG), and Holter monitoring were analyzed via two multivariable predictive modeling strategies (ordinal logistic regression and recursive partitioning) for their abilities to predict the results of EP studies, namely tachyarrhythmic and bradyarrhythmic outcomes. These categories were further divided into full arrhythmia and borderline arrhythmia groups.Important outcomes were 1) sustained monomorphic ventricular tachycardia (VT) and 2) bradyarrhythmias, including sinus node and atrioventricular (AV) conducting disease. The results of the logistic regression (in this study, the superior strategy) showed that the presence of organic heart disease [odds ratio (OR) = 3.0, p less than 0.001] and frequent premature ventricular contractions on ECG (OR = 6.7, p less than 0.004) were associated with VT, while the following abnormal ECG findings were associated with bradyarrhythmias: first-degree heart block (OR = 7.9, p less than 0.001), bundle-branch block (OR = 3.0, p less than 0.02), and sinus bradycardia (OR = 3.5, p less than 0.03). Eighty-seven percent of the 31 patients with important outcomes at EP study had at least one of these clinical risk factors, while 95% of the patients with none of these risk factors had normal or nondiagnostic EP studies. In the validation sample, the presence of one or more risk factors would have correctly identified 88% of the test VT patients and 65% of the test bradyarrhythmia patients as needing EP study.These five identified predictive factors, available from the history, the physical examination, and the initial ECG, could be useful to clinicians in selecting those patients with unexplained syncope who will have a serious arrhythmia identified by EP studies.

Amiodarone effectively maintains sinus rhythm in patients with atrial fibrillation, and although dronedarone is less effective it has a better safety profile. The choice of antiarrhythmic drug (or nonpharmacological strategy) depends on the ultimate goal of therapy, which should be considered in the context of the patient's clinical presentation and the treatment tailored to the individual.