Bachmann's bundle and coronary sinus ostial pacing accentuate left atrial electrical dyssynchrony in an acute canine model.

INTRODUCTION: In patients with intraatrial conduction delay and sinus node (SN) dysfunction, pacing Bachmann's bundle (BBR) and coronary sinus ostium (CSO) has been suggested to achieve atrial resynchronization with potential beneficial impact on atrial fibrillation and diastolic heart failure. Clinical studies have not shown superiority of one approach. METHODS AND RESULTS: We studied electrical activation sequence in an open-chest acute canine model of normal atrial function in 8 mongrel dogs under general anesthesia. Bipolar plunge electrodes were distributed over the surface of the atria during unifocal pacing, and intracardiac activation sequence was observed. SN pacing resulted in near-simultaneous activation at midline sites (BBR and CSO); the left atrium (LA) was activated by anterior and posterior wavefronts simultaneously propagating septally to laterally and meeting at the low-lateral perimitral LA. Right atrial appendage (RAA) pacing created intra-RA conduction delay and delayed onset of LA activation. Pacing from RAA, CSO, and BBR resulted in nonsimultaneous activation at midline sites and produced an anteroposterior gradient of LA activation. This phenomenon was seen to the greatest degree with midline pacing and shifted the site of latest activation away from the low-lateral perimitral LA in all pacing configurations except SN pacing. CONCLUSION: Pacing-induced intra-LA activation dispersion is enhanced with midline atrial pacing, and secondarily shifts the site of latest activation away from the lateral mitral annulus. Measuring atrial activation times to the low-lateral perimitral LA can underestimate the degree of atrial dyssynchrony and be misinterpreted as atrial synchrony. Establishing clinical impact requires evaluation of human data.

Implementation of a Patient Decision Aid for Atrial Fibrillation Ablation Improves Patient Procedural Knowledge but Does Not Impact Perceived Involvement With the Shared Decision-Making Process.

Purpose: Shared decision-making (SDM) is a method for a patient and physician to cooperatively consider a diagnostic or therapeutic option, ultimately empowering the patient to make an informed decision. Atrial fibrillation (AF) ablation is a procedure that would benefit from SDM given the risk of serious adverse events, the high rate of arrhythmia recurrence, and alternative treatment options. Implementing a patient decision aid (PDA) may help facilitate AF ablation SDM by succinctly conveying important information to patients. Methods: Patients scheduled for initial AF catheter ablation were randomized to a virtual SDM visit utilizing a PDA, which covered procedural risks and benefits, or a virtual control visit with a tool outlining periprocedural processes. Preoperatively, patients completed a questionnaire assessing procedural risk and benefit knowledge, as well as perceived involvement with the decision-making process. Unpaired t-tests were used to compare groups. Results: The SDM group scored significantly better overall on knowledge-based questions compared to the control group (69% correct [n=34] vs 53% [n=32]; P=0.00013). In particular, the SDM group was significantly more likely to answer questions correctly about stroke risk (P=0.01), anticoagulation (P=0.01), and potential need for additional procedures (P=0.03 and P=0.03). Perceived involvement in the decision-making process was overall not improved with PDA use (4.7 vs 4.6 out of 5; P=0.72). Conclusions: The addition of a PDA for AF ablation significantly improved procedural knowledge but did not impact patients' perceived involvement in the decision-making process compared to traditional preprocedural discussion alone.

Intentional Oversizing of Valve in Transcatheter Aortic Valve Replacement: Is Bigger Better? A Large, Single-Center Experience.

Background: The current clinical practice standard is 10% to 20% oversizing of self-expanding valves in transcatheter aortic valve replacement. We aimed to determine whether >20% oversizing of self-expanding valves (Medtronic Evolut) would lead to better valve performance with similar or better outcomes. Methods: From October 2011 to December 2016, we approached all transcatheter aortic valve replacement patients with a conscious attempt at large oversizing (>20%). The most common valve used, excluding those used in valve-in-valve patients, was the 29-mm Evolut R (29%). We used a retrospective chart review to compare moderate oversizing (group 1; 10% to 20%) with large oversizing (group 2; >20%). Results: Of 556 patients, 45% were male; the overall mean Society of Thoracic Surgeons risk score was 5.8 ± 3.8. Eighty-five (15%) patients needed a pacemaker, and 21 (3.8%) developed significant paravalvular leak. Mean oversizing was 20.3% ± 6.0%, with 41.4% of patients included in group 1 and 54.5% in group 2. Incidences of complications in group 2 vs. group 1 were as follows: a) paravalvular leak (2.0 vs. 6.1%; odds ratio = 0.31, p = 0.01), b) pacemaker (15 vs. 14%), c) gastrointestinal bleed (n = 4 vs. 0; 1.3 vs. 0.0%; p = 0.03), d) annular dissection (n = 1 vs. 0; 0.3 vs. 0%; p = 0.29), e) mortality (n = 5 vs. 4; 1.6 vs. 1.7%). Incidence of paravalvular leak was higher in those who died than survivors (13 vs. 1.3%; p ≤ 0.0001). Conclusions: These data suggest that, in current self-expanding valves, >20% oversizing delivers a significantly lower prevalence of paravalvular leak without an increase in other complications. Since paravalvular leak is associated with increased mortality, >20% oversizing may represent a superior prosthesis choice.

Large Epicardial Hematoma After Percutaneous Coronary Intervention: Multimodality Imaging.

Epicardial hematoma can manifest immediately or within a few minutes to hours after coronary intervention. Review of angiogram after the diagnosis of hematoma, in our case, showed deep distal positioning of a non-polymer jacketed wire, which is the most likely cause of the adverse outcome. Multimodality imaging is critical for diagnosis and management of such cases.