Elevated plasma NT-proBNP concentrations and LV filling pressures represented by LAA dysfunction may be reliable surrogate markers for predicting thromboembolic risk in patients with AF.

PurposeRhythm-control therapy administered early following the initial diagnosis of atrial fibrillation (AF) has superior cardiovascular outcomes compared to rate-control therapy. Frailty is a key factor in identifying older patients’ potential for improvement after rhythm-control therapy. This study evaluated whether frailty affects the outcome of early rhythm-control therapy in older patients with AF.MethodsFrom the Korean National Health Insurance Service database (2005–2015), we collected 20,611 populations aged ≥65 years undergoing rhythm- or rate-control therapy initiated within 1 year of AF diagnosis. Participants were emulated by the EAST-AFNET4 trial, and stratified into non-frail, moderately frail, and highly frail groups based on the hospital frailty risk score (HFRS). A composite outcome of cardiovascular-related mortality, myocardial infarction, hospitalization for heart failure, and ischemic stroke was compared between rhythm- and rate-control.ResultsEarly rhythm-control strategy showed a 14% lower risk of the primary composite outcome in the non-frail group [weighted incidence 7.3 vs. 8.6 per 100 person-years; hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.79–0.93, p < 0.001] than rate-control strategy. A consistent trend toward a lower risk of early rhythm-control was observed in the moderately frail (HR 0.91, 95% CI 0.81–1.02, p = 0.09) and highly frail (HR 0.93, 95% CI 0.75–1.17, p = 0.55) groups.ConclusionAlthough the degree attenuated with increasing frailty, the superiority of cardiovascular outcomes of early rhythm-control in AF treatment was maintained without increased risk for safety outcomes. An individualized approach is required on the benefits of early rhythm-control therapy in older patients with AF, regardless of their frailty status.

Introduction: His bundle pacing (HBP) was developed as a physiological conduction system pacing to complement the problem of conventional right ventricular pacing (RVP) related to dyssynchrony. Recently, left bundle branch area pacing (LBBAP), which overcomes the shortcomings of HBP, has been implemented. Most researches on initial experiences with LBBAP have reported that it was achieved through a lumen-less pacing lead (LLL) with a fixed helix design; however, there are situations in which LLL cannot be used. The purpose of present research is to evaluate the initial experience and learning curve of LBBAP using a standard stylet-driven lead with an extendable helix design. Methods: 265 patients who underwent LBBAP or conventional RVP performed by operators without previous LBBAP experience at Yonsei University Severance Hospital in Korea between December 2020 and October 2021 were enrolled. LBBAP was performed using a stylet‐driven pacing lead with an extendable helix. The learning curve was evaluated by analyzing fluoroscopy and procedure times. Results: LBBAP was successful in 65 of 69 (94.2%) patients during the observation period. In 65 patients who underwent LBBAP, mean fluoroscopy and procedural times were 17.1 ± 17.2 minutes and 64.2 ± 33.5 minutes, respectively. The learning curve for achieving LBBAP plateaued after the 24th case, with a gradually shortened in procedure time. Conclusion: During the initial experience with LBBAP, fluoroscopy and procedural times improved with increasing operator experience. For operators who were experienced in cardiac pacemaker implantation, the steepest part of the learning curve was over the first 20-25 cases.

Atrial fibrillation (AF) is the most common sustained arrhythmia. AF is caused by inflammation, oxidative stress, and various structural heart diseases. An important key factor in AF promotion is that atrial cardiomyocytes have constitutively active acetylcholine-activated K+ (IKACh) current that is enhanced by the tachycardia. Furthermore, it is known that heat shock proteins (HSPs) are involved in the protection against different forms of cellular stress and recent investigators reported that the HSP inducing compound geranylgeranylacetone (GGA, also known as teprenone) prevents atrial remodeling and attenuates the promotion of AF. Whether GGA and GGA-derivatives prevent the acetylcholine-activated K+ current is unknown. Methods: We examined the effect of HSP inducer GGA and 5 derivatives on IKACh current in mouse atrial cardiomyocytes. In the present study, the IKACh current was recorded using a nystatin-perforated whole cell patch-clamp technique following activation by acetylcholine (10 μM for 2 min). After the measurement of the baseline IKACh current, atrial cardiomyocytes were treated with GGA 10μM or a derivative of GGA (NYK9274, NYK9308, NYK9354, NYK9356 or NYK9376) for 10min and the IKACh current was re-measured. Results: IKACh current in mouse atrial cardiomyocyte treated with acetylcholine (10 μM) was significantly increased, which was markedly attenuated by GGA 10μM treatment (n=5, peak; 54±11.2%, quasi-steady-state; 58±11.4%, p<0.001). In addition, the effects of the GGA derivatives on IKACh were evaluated with same experimental protocol. Our results showed that next to GGA, also NYK9308 and NYK9356 significantly inhibit both peak and quasi-steady-state IKACh. In contrast, NYK9274, NYK9354 and NYK9376 had no effect on IKACh. Conclusion: This study provides important evidences that the HSP inducer GGA facilitates its potent antiarrhythmic effect by inhibiting IKAch, which underlies electrical remodeling in mammalian atrial cardiomyocytes. Furthermore, two GGA derivatives, NYK9308 and NYK9356, with improved pharma-chemical properties compared to GGA, reveal similar protective effects compared to GGA, and provide important background information for the use of GGA and GGA-like compounds in patients with AF.