Increased risk of ischemic stroke associated with new-onset atrial fibrillation complicating acute coronary syndrome: A systematic review and meta-analysis.

BACKGROUND: Atrial fibrillation has been established as a major risk factor of ischemic stroke, however, the influence of new-onset atrial fibrillation (NOAF) complicating acute coronary syndrome (ACS) on ischemic stroke remains controversial. This meta-analysis aimed to validate the association between NOAF complicating ACS and ischemic stroke.

METHODS: We identified randomized controlled trials and cohort studies comparing the ischemic stroke risk between patients with NOAF and sinus rhythm after ACS by searching MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials databases. We included studies reporting the number of ischemic stroke events or their risk estimates at the longest follow-up. We pooled risk ratios (RRs) using a random-effects model. This meta-analysis is registered in PROSPERO (CRD42017079858).

RESULTS: In the 14 included studies (n = 292,774, 5 randomized controlled trials and 9 cohort studies), NOAF was associated with an increased risk of ischemic stroke (RR: 2.84, 95% confidence interval [CI]: 1.91-4.23; 6 studies), especially for patients with ST-segment elevation myocardial infarction (RR: 4.01, 95% CI: 2.61-6.18; 3 studies). In addition, the detrimental impact persisted in patients with transient NOAF (RR: 3.05, 95% CI: 1.63-5.70; 3 studies). The pooled result from a sensitivity analysis in which all individual components in the CHA2 DS2 -VASc score (heart failure, hypertension, age, diabetes, previous stroke, vascular disease and female sex) had been adjusted further validated the association between NOAF and ischemic stroke (RR: 2.32, 95% CI: 1.53-3.52; 4 studies).

CONCLUSIONS: NOAF is significantly associated with ischemic stroke events in patients with ACS, even after adjustment for several important ischemic stroke risk factors.