A study has assessed the effect of Ranolazine, an anti-ischaemic agent with anti-arrhythmic properties, on the overall burden of atrial fibrillation in acute coronary syndromes ( ACS ) and has determined whether Ranolazine reduces the long-term incidence of clinical atrial fibrillation after acute coronary syndrome.
MERLIN-TIMI 36 randomized patients with non-ST elevation ACS to Ranolazine or placebo. Atrial fibrillation episodes detected on continuous electrocardiogram ( cECG ) monitoring were reviewed in 6351 patients ( 97% of trial ).
Atrial fibrillation burden was categorized according to the time in atrial fibrillation: clinically insignificant atrial fibrillation ( less than 0.01% of time ), paroxysmal atrial fibrillation ( more than 0.01-98% ), or predominantly persistent atrial fibrillation ( more than 98% ).
Clinical atrial fibrillation events were identified through adverse event reporting for a median 1-year follow-up. Overall, patients assigned to Ranolazine had a trend towards fewer episodes of atrial fibrillation [ 75 ( 2.4% ) vs. 55 ( 1.7% ) patients, P=0.08 ] detected on cECG during the first 7 days after randomization.
The pattern of new-onset atrial fibrillation differed between Ranolazine versus placebo: clinically insignificant atrial fibrillation ( 5 patients in Ranolazine vs 7 in placebo ), paroxysmal atrial fibrillation ( 18 vs 48 patients ), and predominantly chronic atrial fibrillation ( 28 vs 20 patients, three-way P less than 0.01 ).
Among patients with a paroxysmal atrial fibrillation pattern, the overall burden was lower with Ranolazine than with placebo ( median 4.4 vs16.1%, P = 0.015 ).
Over the median 1-year follow-up, fewer patients treated with Ranolazine experienced an atrial fibrillation event compared with placebo ( 2.9 vs 4.1%, RR=0.71, P = 0.01 ).
In conclusion, Ranolazine, an anti-anginal agent with electrophysiological effects, may reduce the frequency of paroxysmal atrial fibrillation in patients with non-ST elevation acute coronary syndrome with a pattern of lower overall atrial fibrillation burden in this group.
Ranolazine reduced the overall 1-year incidence of clinical atrial fibrillation events.
These atrial-specific anti-arrhythmic properties of Ranolazine may be of clinical interest and warrant additional investigation. ( Xagena )
Scirica BM et al, Europace 2015;17: 32-37