Rate versus rhythm control for management of atrial fibrillation in clinical practice: results from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) registry

Abstract

Background: All patients with atrial fibrillation (AF) require optimization of their ventricular rate. Factors leading to use of additional rhythm control in clinical practice have not been thoroughly defined.

Methods: The ORBIT-AF registry enrolled patients with AF from a broad range of practice settings and collected data on rate versus rhythm control, as indicated by the treating physician. Multivariable logistic regression analysis was performed to identify factors associated with each strategy.

Results: Of 10,061 patients enrolled, 6,859 (68%) were managed with rate only control versus 3,202 (32%) with rhythm control. Patients managed with rate control were significantly older and more likely to have hypertension, heart failure, prior stroke, and gastrointestinal bleeds. They also had fewer AF-related symptoms (41% with no symptoms vs 31% for rhythm control). Systemic anticoagulation was prescribed for 5,448 (79%) rate-control patients versus 2,219 (69%) rhythm-control patients (P < .0001). After multivariable adjustment, patients with higher symptom scores (severe symptoms vs. none, OR 1.62, 95% CI 1.41-1.87) and those referred to electrophysiologists (OR 1.64, 95% CI 1.45-1.85) were more likely to be managed with a rhythm control strategy.

Conclusions: In this outpatient registry of US clinical practice, the majority of patients with AF were managed with rate control alone. Patients with more symptoms and who were treated by an electrophysiologist were more likely to receive rhythm-control therapies. A significant proportion of AF patients, regardless of treatment strategy, were not treated with anticoagulation for thromboembolism prophylaxis.

Figure 1

Unadjusted use of antithrombotic therapies. Aspirin only included aspirin/dipyridamole, (n = 14, 0.14%). Any ADP inhibitor included clopidogrel or prasugrel, with or without aspirin, but no oral anticoagulant. Systemic anticoagulation included warfarin or dabigatran (with any antiplatelet). *P < .05 for the comparison between rate control and rhythm control groups. ADP: adenosine diphosphate.

Figure 2

Unadjusted and adjusted comparisons of medical therapies between strategies. Multivariable rates adjusted for age, left atrial diameter, posterior wall thickness, level of education, site region, medical history of frailty, AF type, and provider specialty. BB, β-blocker; CCB, calcium-channel blocker.

Figure 3

Multivariable analysis of factors associated with AF management strategy. Boxes denote adjusted OR with lines to 95% CIs.