Silent strokes after thoracoscopic epicardial ablation and catheter ablation for atrial fibrillation: not all lesions are permanent on follow-up magnetic resonance imaging

Abstract

Background: Invasive treatments for atrial fibrillation (AF) pose a risk of ischemic stroke due to periprocedural brain embolization, which may be manifest or silent. The primary aim of our study was to compare the rate of silent strokes after percutaneous catheter-based and thoracoscopic epicardial ablation for AF. The secondary aim was to evaluate the development of silent strokes over time.Methods: We included 39 subjects (aged 64.1±8.9 years) treated for persistent symptomatic AF with thoracoscopic ablation and 30 subjects (aged 64.1±10.5 years) treated for paroxysmal or persistent symptomatic AF with catheter ablation. Subjects underwent brain MRI before and early after the ablation, moreover, the surgical group underwent late MRI 6 months after therapy. On early MRI, the presence of silent strokes and their number and size were evaluated. On late MRI, transformation of previously-detected acute ischemic lesions into chronic infarction or their reversibility were assessed.Results: Initially, different chronic ischemic findings were found in 64% of patients from the surgical group and in 70% from catheter group. Early MRI results: acute ischemic lesions were detected in 2 (6.7%) subjects (overall 3 lesions sized <5 mm) in the catheter group and in 17 (43.6%) subjects in surgical group.Most subjects in the surgical group showed multiple lesions (88%); 195 lesions were detected, a median 6 (IQR 8) lesions per case. Eighty-two percent of lesions were <5 mm, 12% 5-10 mm, 5% 10-30 mm, and 2% were large territorial ischemia. Only 1 case was symptomatic, the rest were silent strokes. On late MRI, 53.5% of all acute lesions were reversible. Lesions <5 mm were reversible in 63.1% of cases, lesions 5-10 mm were reversible in 21.7% and all lesions larger than 10 mm persisted. In 29.4% of patients all acute ischemic lesions were fully reversible.Conclusions: Periprocedural silent strokes were significantly more common after thoracoscopic epicardial ablation compared to catheter ablation considering both the number of affected patients and number of lesions. The majority of acute ischemic brain lesions were small, up to 5 mm in diameter, roughly half of which were reversible. Reversibility of acute ischemic lesions decreased with size. However, in 29.4% of affected patients, all lesions were fully reversible.

Changes in cognitive function after thoracoscopic and catheter ablation for atrial fibrillation

“…12 Moreover, compared to patients after CA, not only was the number of patients with new lesions greater after hybrid ablation but so was the number of lesions per patient. 13 However, we did not find any correlation between the number of silent lesions or the amount of ischemia and neurocognitive decline. This agrees with reports by Schwartz and Herm, who also failed to find any correlation between the number of microlesions detected on MRI and neurocognitive decline.…”

“…In our series of hybrid ablation patients, new acute ischemic lesions were seen on MRI in 44% of patients 2−4 days after the surgical procedure 12 . Moreover, compared to patients after CA, not only was the number of patients with new lesions greater after hybrid ablation but so was the number of lesions per patient 13 . However, we did not find any correlation between the number of silent lesions or the amount of ischemia and neurocognitive decline.…”

Diagnosis of Ischemic Stroke: As Simple as Possible

“…Hyperacute ischemic changes are detectable as early as minutes to hours from arterial occlusion [ 51 ]. The area of high signal intensity on DWI does not unequivocally mean ischemic core, as cytotoxic edema itself may be reversible [ 7 ]. Later when cell membrane disruption develops and vasogenic edema appears, not only DWI but also T2 signal increases and positivity on T2 FLAIR appears, which indicates the onset of irreversible ischemic changes [ 51 ].…”

“…Notably, the TOAST classification does not include silent strokes, which have recently garnered greater interest due to progress in cardiac surgery and interventional cardiac procedures. Silent strokes are defined as imaging findings of acute infarction primarily on MRI without neurological manifestation in common bed-side examinations [ 7 , 8 ].…”

CT Brain Perfusion in the Prediction of Final Infarct Volume: A Prospective Study of Different Software Settings for Acute Ischemic Core Calculation

“…We have been studying diagnostic and therapeutic possibilities in AIS patients for several years [ 15 , 16 , 17 ]. In the present study, we evaluated the accuracy of three different syngo.via settings in the estimation of the acute ischemic core on CTP.…”