Atrial Fibrillation Associated with Poor Outcomes After Mechanical Thrombectomy for Stroke

Hassan Kobeissi, BS

Individuals with atrial fibrillation (AF) treated with mechanical thrombectomy for acute ischemic stroke (AIS) experienced worse 90-day outcomes than those without AF, according to a systematic review and meta-analysis of 10 studies.

The outcomes included significantly higher rates of mortality and significantly lower rates of functional independence after mechanical thrombectomy compared to those without AF, even with comparable, successful reperfusion outcomes.

“These findings are important because they provide context for the worse outcomes observed in patients with AF compared with patients without AF,” wrote study author Hassan Kobeissi, BS, Department of Radiology, Mayo Clinic.

Mechanical thrombectomy is the gold standard to treat patients with acute ischemic stroke (AIS) with large-vessel occlusion. Previous studies have suggested that outcomes following AIS for patients with AF are worse compared with patients without AF.

Kobeissi noted that understanding the differences in outcomes between patients with AF vs. without AF receiving mechanical thrombectomy is clinically relevant. Their analysis of existing literature that reported outcomes among patients with AF and without AF who underwent mechanical thrombectomy for AIS compared procedural outcomes, functional outcomes, and characteristics between patient populations.

The team performed a review of English language literature from inception to July 2022 and was conducted using Web of Science, Embase, Scopus, and PubMed databases. They included all original studies fulfilling our predetermined Population, Exposure, Comparator, and Outcomes approach.

The study population was patients with AIS with AF, the exposure was mechanical thrombectomy, the control group was patients with AIS without AF, and the primary outcome of interest was modified Rankin Scale (mRS) score of 0 to 2. Secondary outcomes of interest were mortality, thrombolysis in cerebral infarction (TICI) score of 2b to 3, and symptomatic intracerebral hemorrhage (SICH).

A total of 1696 studies were initially retrieved, of which 10 studies were included with 6543 patients meeting inclusion criteria. Patients with AF were a mean of 10.17 (95% CI, 8.11 - 12.23) years older than their counterparts without AF (P <.001).

Those with AF had significantly higher rates of hypertension (OR, 1.89; 95% CI, 1.57 - 2.27; P <.001) and diabetes (OR, 1.16; 95% CI, 1.02 - 1.31; P = .02), with no significant heterogeneity between studies.

Investigators additionally found there were comparable rates of functional independence (mRS score of 0-2) at 90 days between patients with AIS with or without AF (odds ratio [OR], 0.72; 95% CI, 0.47 - 1.10; P = .13). They noted, however, that there was significant heterogeneity among the included studies.

Other findings from the sensitivity analysis revealed significantly lower rates of functional independence among patients with AF compared with patients without AF (OR, 0.65; 95% CI, 0.52 - 0.81; P <.001). They added that successful reperfusion rates were similar between patients with and without AF (OR, 1.11; 95% CI, 0.78 - 1.58; P = .57).

Nine of the studies with 5614 patients compared the rates of symptomatic intracranial hemorrhage (SICH) and found them similar between groups (OR, 1.05; 95% CI, 0.84 - 1.31; P = .68). Data also show mortality was significantly higher in the AF group (OR, 1.47; 95% CI, 1.12 - 1.92; P = .005).

Investigators noted that patients with AF tend to be older, with previous findings suggesting that younger patients have better outcomes following mechanical thrombectomy for AIS. Patients with AF in the analysis were approximately 10 years older compared with patients without AF.

“It is possible that patients with AF have worse outcomes because of these traits, instead of AF itself contributing to the worse outcomes,” Kobeissi wrote.

The study, “Outcomes of Patients With Atrial Fibrillation Following Thrombectomy for Stroke: A Systematic Review and Meta-Analysis,” was published in JAMA Network Open.