What can rhythm control therapy contribute to prognosis in atrial fibrillation?

Optimal Rhythm Control Strategy in Patients With Atrial Fibrillation

In the recent EAST-AFNET 4 trial, early rhythm control reduced the risk of adverse cardiovascular events compared with usual care in patients recently diagnosed as atrial fibrillation (AF). Recent observational studies from Korean nationwide claim data confirmed and extended the findings from controlled trials. The beneficial effect of rhythm control on cardiovascular outcomes was not obvious in those who had been diagnosed with AF more than 1 year ago. Especially, early initiation of rhythm control was related to the lower risk of stroke and hospitalization due to heart failure. Finally, early rhythm control treatment was also effective in patients with asymptomatic AF but less effective in older adults. Therefore, in patients with AF, rhythm control should be considered at the earliest stage, regardless of symptom.

For almost 20 years, data regarding the effect of rhythm control therapy for atrial fibrillation (AF) on cardiovascular prognosis in comparison with rate control therapy has not been conclusive. The safety of rhythm control and anticoagulation therapy has generally improved. Recently, it was revealed that a rhythm-control strategy reduced the risk of adverse cardiovascular events than usual rate control in patients with recent AF (diagnosed within 1 year). Within 1 year after the AF diagnosis, early initiation of rhythm control led to more favorable cardiovascular outcomes than rate control. Early rhythm control reduced the risks of stroke and heart failure-related admission than rate control. Moreover, rhythm control was associated with lower dementia risk than rate control. Finally, early rhythm control treatment was also effective in patients with asymptomatic AF but less effective in older adults. Therefore, in patients with AF, rhythm control should be considered at earlier stages, regardless of symptom.

Comparative Effectiveness of Early Rhythm Control Versus Rate Control for Cardiovascular Outcomes in Patients With Atrial Fibrillation

Background Rhythm control is associated with better cardiovascular outcomes than usual care among patients with recently diagnosed atrial fibrillation (AF). This study investigated the effects of rhythm control compared with rate control on the incidence of stroke, heart failure, myocardial infarction, and cardiovascular death stratified by timing of treatment initiation. Methods and Results We conducted a retrospective population-based cohort study including 22 635 patients with AF newly treated with rhythm control (antiarrhythmic drugs or ablation) or rate control in 2011 to 2015 from the Korean National Health Insurance Service database. Propensity overlap weighting was used. Compared with rate control, rhythm control initiated within 1 year of AF diagnosis decreased the risk of stroke. The point estimates for rhythm control initiated at selected time points after AF diagnosis are as follows: 6 months (hazard ratio [HR], 0.76; 95% CI, 0.66-0.87), 1 year (HR, 0.78; 95% CI, 0.66-0.93), and 5 years (HR, 1.00; 95% CI, 0.45-2.24). The initiation of rhythm control within 6 months of AF diagnosis reduced the risk of hospitalization for heart failure: 6 months (HR, 0.84; 95% CI, 0.74-0.95), 1 year (HR, 0.96; 95% CI, 0.82-1.13), and 5 years (HR, 2.88; 95% CI, 1.34-6.17). The risks of myocardial infarction and cardiovascular death did not differ between rhythm and rate control regardless of treatment timing. Conclusions Early initiation of rhythm control was associated with a lower risk of stroke and heart failure-related admission than rate control in patients with recently diagnosed AF. The effects were attenuated as initiating the rhythm control treatment later.

Comparative occurrence of ischemic stroke with the rhythm versus rate control strategy in a national prospective cohort of atrial fibrillation

BACKGROUND/AIMS

Comparative occurrence of ischemic stroke for rhythm versus rate control strategy in patients with non-valvular atrial fibrillation (NVAF) is still inconclusive. The purpose of this study was to investigate whether the rhythm control strategy is associated with a lower risk of ischemic stroke compared to the rate control strategy in NVAF patients.

METHODS

The CODE-AF registry prospectively enrolled 6,280 consecutive patients who were treated for NVAF at 10 tertiary referral centers in South Korea. Of these, 2,513 NVAF patients (age, 67 ± 10 years; male, 61.8%) were clinically followed up for over 1-year and divided into rate and rhythm control groups.

RESULTS

Those treated with the rhythm control strategy were younger and had less proportions of underlying disease compared to those treated with the rate control strategy. After the propensity matching analysis, those treated with the rhythm control strategy had similar baseline characteristics including the CHA2DS2-VASC score compared to those treated with the rate control strategy. The rate of oral anticoagulation, all bleeding, and hospitalization were also similarly between the two groups. The incidence rate of ischemic stroke in the rhythm control group was significantly lower than in the rate control group (0.7 vs. 6.9 per 1,000 person-years, p = 0.011).

CONCLUSION

The rhythm control strategy demonstrated a beneficial effect to lower the risk of ischemic stroke during a 1-year follow-up compared to the rate control strategy.

Comparison of Rhythm and Rate Control Strategies for Stroke Occurrence in a Prospective Cohort of Atrial Fibrillation Patients

PURPOSE

Comparisons of rhythm and rate control strategies for stroke prevention in patients with atrial fibrillation (AF) are still inconclusive. We compared differences in clinical outcomes between the rhythm and rate control strategies.

MATERIALS AND METHODS

The COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation (CODE-AF) registry prospectively enrolled 6000 patients who were treated for AF using real-world guideline adherence at multiple referral centers. In total, 2508 (41.8%) patients were clinically followed up for over six months. Of these, 1134 (45.2 %) patients treated by rhythm control and 1374 (54.8 %) patients treated by rate control were analyzed for clinical outcomes, including stroke and cardiovascular outcomes.

RESULTS

Among all patients (age, 68±10 years; male, 62.4%), those treated with the rhythm control strategy were significantly younger, had more symptomatic paroxysmal AF, and a shorter AF duration, and were less likely to have diabetes, renal dysfunction, and heart failure, compared to those treated with the rate control strategy (CHA₂DS₂-VASc score 2.4±1.5 vs. 3.1±1.7, p<0.001). Even though oral anticoagulation was similarly prescribed in both groups, occurrence of stroke was less likely to occur in the rhythm control strategy group (0.0% vs. 0.7%, p=0.015). Multivariate Cox hazard regression showed that only age, especially more than 75 years old, were significantly correlated with the occurrence of stroke, regardless of the strategy used for treatment.

CONCLUSION

In this prospective AF cohort, compared with the rate control strategy, the rhythm control strategy was associated with fewer cardiovascular events and strokes in a short-term period.

Antiarrhythmic drug therapy among patients presenting to emergency department with symptomatic atrial fibrillation - a prospective nationwide cohort

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia that causes numerous visits to emergency departments (ED). The aim of the FinFib2 study was to evaluate whether treatment of patients with AF in ED is consistent with the contemporary European Society of Cardiology (ESC) management guidelines. Here we report the results of antiarrhythmic drug therapy (AAD) in ED.

METHODS

All patients within the two-week study period whose primary reason for the ED visit was symptomatic AF were included into this prospective multicentre study. Comprehensive data on factors contributing to the treatment of AF were collected, including a data of previous use of ADDs, and changes made for them during a visit in ED.

RESULTS

The study population consisted of 1013 consecutive patients (mean age 70 ± 13 years, 47.6% female). The mean European Heart Rhythm Association (EHRA) symptom score was 2.2 ± 0.8. Rhythm control strategy was opt for 498 (63.8%) and 140 (64.5%) patients with previously and newly diagnosed AF, respectively. In patients with previously diagnosed AF the most frequently used AAD was a beta blocker (80.9%). Prior use of class I (11.4%) and III (9.1%) AADs as well as start or adjustment of their dosage (7.4%) were uncommon. Most of the patients with newly diagnosed AF were prescribed a beta blocker (71.0%) or a calcium channel antagonist (24.0%), and only two of them received class I or class III AADs.

CONCLUSIONS

Our data demonstrated that in patients presenting to the ED with recurrent symptomatic AF and aimed for rhythm control strategy, the use of class I and class III AADs was rare despite ESC guideline recommendations. It is possible that early adaptation of a more aggressive rhythm control strategy might improve a quality of life for symptomatic patients and alleviate the ED burden associated with AF. Beta blockers were used by majority of patients as rate control therapy both in rate and rhythm control groups.

TRIAL REGISTRATION

NCT01990105 . Registered 15 November 2013.

Utilization and Predictors of Electrical Cardioversion in Patients Hospitalized for Atrial Fibrillation

Atrial fibrillation (AF) is a common arrhythmia in adults associated with thromboembolic complications. External electrical cardioversion (DCCV) is a safe procedure used to convert AF to normal sinus rhythm. We sought to study factors that affect utilization of DCCV in hospitalized patients with AF. The study sample was drawn from the Nationwide Inpatient Sample (NIS) of the Healthcare Cost and Utilization Project in the United States. Patients with a primary discharge diagnosis of AF that received DCCV during hospitalization in the years 2000–2010 were included. An estimated 2,810,530 patients with a primary diagnosis of AF were hospitalized between 2001 and 2010, of which 1,19,840 (4.26%) received DCCV. The likelihood of receiving DCCV was higher in patients who were males, whites, privately insured, and aged < 40 years and those with fewer comorbid conditions. Higher CHADS2 score was found to have an inverse association with DCCV use. In-hospital stroke, in-hospital mortality, length of stay, and cost for hospitalization were significantly lower for patients undergoing DCCV during AF related hospitalization. Further research is required to study the contribution of other disease and patient related factors affecting the use of this procedure as well as postprocedure outcomes.