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.

Secondary prevention of antithrombotic therapy in patients with stable cardiovascular disease at high ischemic risk: A network meta-analysis of randomized controlled trials

Aims

Antithrombotic secondary prevention in stable cardiovascular disease (SCVD) patients at high ischemic risk remains unclear. We compared the efficacy and safety of aspirin monotherapy, clopidogrel monotherapy, ticagrelor monotherapy, rivaroxaban monotherapy, clopidogrel plus aspirin, ticagrelor plus aspirin, and rivaroxaban plus aspirin in the high-risk ischemic cohorts.

Methods and results

Eleven randomized controlled trials were included (n = 111737). The primary outcomes were major cardiovascular and cerebrovascular events (MACEs) and major bleeding. A random effects model was used for frequentist network meta-analysis. Odds ratio (OR) and 95% credible intervals (CI) were reported as a summary statistic. Compared with aspirin monotherapy, rivaroxaban plus aspirin [OR 0.79 (95% CI, 0.69, 0.89)], ticagrelor plus aspirin [0.88 (0.80, 0.98)], clopidogrel plus aspirin [0.56 (0.41, 0.77)] were associated with a reduced risk of MACEs, but rivaroxaban monotherapy [0.92 (0.79, 1.07)], ticagrelor monotherapy [0.68 (0.45, 1.05)], and clopidogrel monotherapy [0.67 (0.43, 1.05)] showed no statistically significant difference. However, rivaroxaban monotherapy and all dual antithrombotic strategies increased the risk of major bleeding to varying degrees, with ticagrelor plus aspirin associated with the highest risk of major bleeding. The net clinical benefit favored clopidogrel or ticagrelor monotherapy, which have a mild anti-ischemic effect without an increase in bleeding risk.

Conclusion

The present network meta-analysis suggests that clopidogrel or ticagrelor monotherapy may be recommended first in this cohort of SCVD at high ischemic risk. But clopidogrel plus aspirin or rivaroxaban plus aspirin can still be considered for use in patients with recurrent MACEs.