Stroke Recurrence in Embolic Stroke of Undetermined Source Without Atrial Fibrillation on Invasive Cardiac Monitoring.

BACKGROUND: More than half of patients with embolic stroke of undetermined source (ESUS) suffer from recurrent ischaemic stroke, despite the absence of atrial fibrillation (AF) on invasive cardiac monitoring (ICM). This study investigated the predictors and prognosis of recurrent stroke in ESUS without AF on ICM. METHOD: This prospective study included patients with ESUS at two tertiary hospitals from 2015 to 2021 who underwent comprehensive neurological imaging, transthoracic echocardiography, and inpatient continuous electrographic monitoring for ≥48 hours prior to ICM for definitive exclusion of AF. Recurrent ischaemic stroke, all-cause mortality, and functional outcome by the modified Rankin scale (mRS) at 3 months were evaluated in patients without AF. RESULTS: Of 185 consecutive patients with ESUS, AF was not detected in 163 (88%) patients (age 62±12 years, 76% men, 25% prior stroke, median time to ICM insertion 26 [7, 123] days), and stroke recurred in 24 (15%) patients. Stroke recurrences were predominantly ESUS (88%), within the first 2 years (75%), and involved a different vascular territory from qualifying ESUS (58%). Pre-existing cancer was the only independent predictor of recurrent stroke (adjusted hazard ratio [AHR] 5.43, 95% CI 1.43-20.64), recurrent ESUS (AHR 5.67, 95% CI 1.15-21.21), and higher mRS score at 3 months (ß 1.27, 95% CI 0.23-2.42). All-cause mortality occurred in 17 (10%) patients. Adjusting for age, cancer, and mRS category (≥3 vs <3), recurrent ESUS was independently associated with more than four times greater hazard of death (AHR 4.66, 95% CI 1.76-12.34). CONCLUSIONS: Patients with recurrent ESUS are a high-risk subgroup. Studies elucidating optimal diagnostic and treatment strategies in non-AF-related ESUS are urgently required.

Clinical Outcomes in Conduction System Pacing Compared to Right Ventricular Pacing in Bradycardia.

BACKGROUND: Conduction system pacing (CSP) provides more physiological ventricular activation than right ventricular pacing (RVP). OBJECTIVES: This study evaluated the differences in clinical outcomes in patients receiving CSP and RVP. METHODS: Consecutive patients with pacemakers implanted for bradycardia from 2016 to 2021 in 2 centers were prospectively followed for the primary composite outcome of heart failure (HF) hospitalizations, upgrade to biventricular pacing, or all-cause mortality, stratified by ventricular pacing burden (Vp) . RESULTS: Among 860 patients (mean age 74 ± 11 years, 48% female, 48% atrioventricular block), 628 received RVP and 231 received CSP (95 His-bundle pacing, 136 left bundle branch pacing). The primary outcome occurred in 217 (25%) patients, more commonly in patients with RVP than CSP (30% vs 13%, P < 0.001). In multivariable analyses, CSP was independently associated with 47% reduction of the primary outcome (adjusted hazard ratio [AHR]: 0.53; 95% CI: 0.29-0.97; P = 0.04) and HF hospitalization alone (AHR: 0.40; 95% CI: 0.17-0.95; P = 0.04), among only patients with Vp >20%. The incidence of the primary outcome was highest among RVP with Vp >20% and lowest in CSP with Vp >20% (35% vs 10%, P < 0.001). Compared with RVP with Vp >20%, both CSP with Vp >20% (AHR: 0.51; 95% CI: 0.28-0.91; P = 0.02) and all patients with Vp ≤20% (AHR: 0.73; 95% CI: 0.54-0.99; P = 0.04) were independently associated with reduced primary outcome, driven primarily by reductions in HF hospitalizations (P < 0.05). Event-free survival was similar between CSP with Vp >20% and those needing ≤20% Vp. CONCLUSIONS: CSP significantly reduced adverse clinical outcomes for bradycardic patients requiring ventricular pacing and should be the preferred pacing modality of choice.