Safety and efficacy of long-term Sodium Channel Blocker therapy for Early Rhythm Control: The EAST-AFNET 4 trial

BACKGROUND AND AIMS

Clinical concerns exist about the potential proarrhythmic effects of the sodium channel blockers flecainide and propafenone (SCB) in patients with cardiovascular disease. SCB were used to deliver early rhythm control (ERC) therapy in EAST-AFNET 4.

METHODS

We analysed the primary safety outcome (death, stroke, or serious adverse events related to rhythm-control therapy) and primary efficacy outcome (cardiovascular death, stroke and hospitalization for worsening of heart failure or acute coronary syndrome) during SCB-intake for ERC patients (n = 1395) in EAST-AFNET 4. The protocol discouraged flecainide and propafenone in patients with reduced left ventricular ejection fraction and suggested stopping therapy upon QRS prolongation >25% on therapy.

RESULTS

Flecainide or propafenone was given to 689 patients (age 69 (8) years; CHA2DS2-VASc 3.2 (1); 177 with heart failure; 41 with prior myocardial infarction, CABG or PCI; 26 with left ventricular hypertrophy >15 mm; median therapy duration 1,153 [237, 1,828] days). The primary efficacy outcome occurred less often in patients treated with SCB (3/100 (99/3,316) patient-years) than in patients who never received SCB (SCBnever 4.9/100 (150/3,083) patient-years, p < 0.001). There were numerically fewer primary safety outcomes in patients receiving SCB (2.9/100 (96/3,359) patient-years) than in SCBnever patients (4.2/100 (135/3,220) patient-years, adjusted p = 0.015). Sinus rhythm at 2 years was similar between groups (SCB 537/610 (88); SCBnever 472/579 (82)).

CONCLUSION

Long-term therapy with flecainide or propafenone appeared to be safe in the EAST-AFNET 4 trial to deliver effective ERC therapy, including in selected patients with stable cardiovascular disease such as coronary artery disease and stable heart failure.

CLINICAL TRIAL REGISTRATION

ISRCTN04708680, NCT01288352, EudraCT2010-021258-20, www.easttrial.org.

Expert Consensus on Comprehensive Early Rhythm Control in Addition to Guideline-Based Care for Atrial Fibrillation: A Modified Delphi Survey

Atrial fibrillation (AF) practice guidelines recommend a rhythm-control strategy to improve symptoms and quality of life, noting the side effects of antiarrhythmic drugs and catheter ablation. Emerging evidence indicates that comprehensive early rhythm control with antiarrhythmic drugs or catheter ablation is associated with a lower risk of adverse cardiovascular outcomes versus the usual care. Using an online modified Delphi survey approach, perspectives and expert consensus among electrophysiologists were examined through a series of ranking and likelihood questions around treatment decision-making on (1) the use of comprehensive early rhythm-control strategies in patients with AF based on guidelines and emerging research and (2) treatment selection factors. A panel of 17 electrophysiologists reached a consensus on using early rhythm control (median 90, interquartile range 14) based on the view that early intervention improved cardiovascular outcomes (mean rank 1.6 of 3, 82% within 1 SD) and symptoms (1.8 of 3, 41%). AF-related symptoms were identified as the most important in making a treatment initiation decision (1.1 of 7, 88%), followed by AF type (2.5 of 7, 82%). Participants were most likely to initiate treatment at AF symptom onset (median 80; interquartile range 6). In making treatment selection decisions, participants ranked short-term/long-term safety (1.9 of 7, 88%) and efficacy (1.8 of 7, 53%) as the top 2 considerations. In conclusion, experts were in favor of early rhythm control; however, additional research is needed to address the role that early rhythm-control strategies play in current AF treatment management algorithms.

rate control in atrial fibrillation: A systematic review and meta-analysis

Objective

It has long been debated whether rhythm control vs. rate control strategies have differing effects on mortality and morbidity for atrial fibrillation (AF). Recently, several randomized controlled studies (RCTs) and observational trials described that an early rhythm management method was linked to a lower likelihood of negative clinical outcomes in individuals with AF. We wanted to see if an early rhythm management method may help patients with AF.

Methods

We performed a systematic search to retrieve studies assessing the outcomes of early rhythm control vs. rate control in AF by using PubMed, Web of Science, Cochrane Library, and Embase published between 01/01/2000 and 15/04/2022.

Results

Finally, two RCTs, one retrospective analysis of RCTs, and four observational studies were identified. Compared with rate control, early rhythm control has been linked to lower all-cause mortality. [risk ratio (RR), 0.76; 95% CI 0.69-0.83; P < 0.00001; I ² = 77%]. The early rhythm control group was also associated with a lower risk of cardiovascular mortality (RR, 0.68; 95% CI 0.63-0.74; P < 0.00001; I ² = 33), stroke (RR, 0.77; 95% CI 0.67-0.87; P < 0.001; I ² = 64), and heart failure hospitalization (RR, 0.74; 95% CI 0.59-0.93; P = 0.0009; I ² = 93%). We found no significant difference in nights spent in hospital per year, acute coronary syndrome, major bleeding, and cardiac arrest/ventricular arrhythmia between the groups.

Conclusion

In this meta-analysis, early rhythm therapy was linked to a lower risk of all-cause mortality, cardiovascular mortality, stroke, and heart failure hospitalization compared with the rate control group.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022333592.