Recent left atrial appendage occlusion (LAAO) research published in JACC: Clinical Electrophysiology and JACC: Advances explores outcomes in patients with prior intracranial hemorrhage (ICH) as well as those with prior ischemic stroke despite oral anticoagulation (OAC) and compares adjudicated registry-reported events with claims data. Two of these studies used data from ACC's LAAO Registry.

The first study, published in JACC: Clinical Electrophysiology, found that LAAO is a reasonable treatment for patients with prior ICH.

Moussa C. Mansour, MD, FACC, et al., included 133,947 patients captured by ACC's LAAO Registry from January 2016 to September 2021; 118,519 had no history of ICH while 15,428 had prior ICH. The study's primary outcomes were combined ischemic/undetermined stroke/transient ischemic attack and ICH.

The adjusted hazard ratios of the primary outcomes were higher in the group with prior ICH (combined ischemic/undetermined stroke/transient ischemic attack, 1.39; 95% CI, 1.25-1.54; and ICH, 3.15; 95% CI, 2.69-3.68).

Over a median 380-day follow-up period, the authors observed an increase in the occurrence of neurologic complications among patients with prior ICH. Nevertheless, overall event rates were low (1.65% in the group with no ICH history vs. 3.56% in the group with prior ICH; p<0.0001).

"Putting the actual event rates into perspective based on the existing literature suggests that the overall rates in both groups are still relatively low," write the authors. "Predictions based on CHA₂DS₂-VASc score for recurrent stroke without intervention… would suggest LAAO therapeutic benefit in both groups."

Another study published in JACC: Clinical Electrophysiology found that patients with a history of ischemic stroke despite oral anticoagulation (OAC) who underwent LAAO had a greater risk of future ischemic stroke but no difference in cardiovascular death.

Including 1,418 patients with nonvalvular atrial fibrillation from the Optimized Catheter Valvular Intervention-Left Atrial Appendage Closure registry, Tadatomo Fukushima, MD, et al., identified three groups: those with no ischemic stroke history, ischemic stroke history despite OAC and ischemic stroke history without OAC. The primary outcomes analyzed were cardiovascular death and ischemic stroke during a median follow-up of 367 days.

No difference was found in cardiovascular death across the three study groups (previous ischemic stroke despite OAC, subdistribution HR [sHR], 1.78; 95% CI, 0.87-3.64; previous ischemic stroke without OAC, sHR, 1.45; 95% CI, 0.59-3.55) and the rate of ischemic stroke following LAAO was higher among those who suffered previous ischemic stroke despite OAC (sHR, 2.62; 95% CI, 1.17-5.86; p=0.02; previous ischemic stroke without OAC, sHR, 1.24; 95% CI, 0.36-4.28; p=0.70).

"The previous [ischemic stroke] despite OAC group was also more likely to have a history of PCI or [CABG] and concomitant carotid stenosis, and systematic atherosclerosis may play a role as a remaining risk for recurrence of [ischemic stroke] after [LAAO]," write the authors.

In a study from JACC: Advances comparing adjudicated registry-reported events captured by the ACC's LAAO Registry with claims data, Kamil F. Faridi, MD, MSc, et al., found moderate agreement with stroke, gastrointestinal bleeding (GIB) and ICH; however, ICD-10 codes overestimated event rates for most stroke and bleeding outcomes.

The authors included 71,043 patients from the registry, linking the data to Medicare claims from 2016 to 2021. They estimated the sensitivity and positive predictive value of claims for identifying registry-reported events.

Sensitivity and positive predictive value were 60.8% and 50.5% for ischemic stroke (kappa 0.55), 42.7% and 50.5% for hemorrhagic stroke (kappa 0.46), 55.9% and 40.3% for GIB (kappa 0.43), 62.2% and 38.0% for ICH (kappa 0.47), and 20.4% and 10.0% for other major bleeding (kappa 0.12).

The authors also found that two-year incidence rates were higher in claims data vs. registry data for all events except hemorrhagic stroke.

"Given that accuracy of event ascertainment from claims data are limited compared to events identified with adjudication methods in the LAAO Registry, our data suggest that claims should not be completely relied upon as the sole data source for stroke or major bleeding in post-marketing surveillance studies," note the authors.