An Analysis of Telehealth in the Outpatient Management of Atrial Fibrillation During the COVID-19 Pandemic.

The COVID-19 pandemic accelerated adaption of a telehealth care model. We studied the impact of telehealth on the management of atrial fibrillation (AF) by electrophysiology providers in a large, multisite clinic. Clinical outcomes, quality metrics, and indicators of clinical activity for patients with AF during the 10-week period of March 22, 2020 to May 30, 2020 were compared with those from the 10-week period of March 24, 2019 to June 1, 2019. There were 1946 unique patient visits for AF (1,040 in 2020 and 906 in 2019). During 120 days after each encounter, there was no difference in hospital admissions (11.7% vs 13.5%, p = 0.25) or emergency department visits (10.4% vs 12.5%, p = 0.15) in 2020 compared with 2019. There was a total of 31 deaths within 120 days, with similar rates in 2020 and 2019 (1.8% vs 1.3%, p = 0.38). There was no significant difference in quality metrics. The following clinical activities occurred less frequently in 2020 than in 2019: offering escalation of rhythm control (16.3% vs 23.3%, p <0.001), ambulatory monitoring (29.7% vs 51.7%, p <0.001), and electrocardiogram review for patients on antiarrhythmic drug therapy (22.1% vs 90.2%, p <0.001). Discussions about risk factor modification were more frequent in 2020 compared with 2019 (87.9% vs 74.8%, p <0.001). In conclusion, the use of telehealth in the outpatient management of AF was associated with similar clinical outcomes and quality metrics but differences in clinical activity compared with traditional ambulatory encounters. Longer-term outcomes warrant further investigation.

Prospective evaluation of the effect of smartphone electrocardiogram usage on anticoagulant medication compliance.

PURPOSE: Compliance with anticoagulation treatment for atrial fibrillation is highly variable. Smartphone electrocardiograms that allow patients to have greater insight into their arrhythmia burden may improve anticoagulant compliance. METHODS: Patients were enrolled if they had atrial fibrillation with a CHA2DS2-VASc score of 2 or more, were eligible for anticoagulation and had a smartphone. Participants were randomly assigned to receive a smartphone electrocardiogram (AliveCor Kardia) to record their electrocardiograms 5 times/week or to the control group. All patients received 6 months of anticoagulant (apixaban) dispensed as 1-month pre-loaded pill boxes. RESULTS: A total of 100 patients were enrolled from July 2017 to August 2019, but 5 patients in the monitor arm and 1 in the control arm withdrew prematurely. The monitor and control groups did not differ in age, gender, CHA2DS2-VASc score, or comorbidities. Median medication compliance was 99.7%, with nonsignificantly greater compliance in the monitor group (100%) than in the control group (99.7%) (p-value = 0.247). There was also no significant difference between missing any dose and use/nonuse of the smartphone monitor (48.9% vs. 55.1%; p-value = 0.692). Mean monitor compliance was 86.8% ± 14.0% with an average of 4.34 recorded electrocardiograms per week. Monitor group patients with perfect medication compliance had significantly higher monitor compliance than those patients who missed doses (median 95.3% vs 86.7%; p-value = 0.02). CONCLUSIONS: In a study population with higher-than-expected medication compliance, the use of smartphone electrocardiogram did not demonstrate an improvement in medication compliance as compared to usual care. Greater monitor compliance was associated with greater medication compliance. CLINICAL TRIAL REGISTRATION: BOAT-OAR ClinicalTrials.gov number, NCT03515083.

Comparative outcomes of vascular access closure methods following atrial fibrillation/flutter catheter ablation: insights from VAscular Closure for Cardiac Ablation Registry.

PURPOSE: This registry compared the safety and efficacy of vascular closure device Perclose (PC) with figure-of-eight stitch (Fo8) and manual compression (MC) following catheter ablation of atrial fibrillation/flutter. METHODS: VAscular Closure for Cardiac Ablation Registry (VACCAR) is a prospective, observational registry that assessed the time to hemostasis (TTH), time to ambulation (TTA), length of stay (LOS), complications, patient-reported outcomes, and pain medication use. RESULTS: A total of 434 patients (mean age 64.0±11.0 years; 38% female; 94.9% white) were enrolled between October 2017 and May 2019: 156 in MC, 203 in Fo8, and 75 in the PC group. Median TTH was significantly reduced in the PC and Fo8 group at 7 and 9 min respectively vs. the MC group at 20 min (p<0.001). Median TTA was significantly reduced in both the PC and Fo8 group at 2.2 h vs. the MC group at 6.5 h (p<0.001 for both). Median LOS for the PC group was significantly reduced at 27.5 h compared to the MC and Fo8 group at 29 h (p<0.01). A higher proportion of same-day discharges were noted in the PC and Fo8 groups at 14 (18.7%) and 25 (12.3%), respectively, compared to 5 (3.2%) in the MC group (p<0.01 for all). There was no significant difference in complications between the three groups. CONCLUSIONS: Both PC and Fo8 are safe with improved TTH, TTA, LOS, and a higher number of same-day discharges compared to MC.

Outcomes using a single tapered dilator for Micra leadless pacemaker implant.

OBJECTIVES: Comparison of outcomes, device deployment time (DT), and total time (TT) using a single tapered Coons dilator versus sequential serial dilation for implantation of the Micra leadless pacemaker. BACKGROUND: Micra leadless pacemaker placement requires a 23 French Micra introducer sheath (MIS) for percutaneous delivery. We sought to evaluate outcomes with use of a single tapered Coons dilator (CD) versus sequential serial dilatation (SD) method to facilitate insertion of the Micra introducer sheath. METHODS: 35 patients were included in the SD arm and 49 in the CD arm. DT and TT were recorded in minutes and cost in dollars. Analysis was performed using independent t-test between two groups and one-way ANOVA to evaluate inter-operator variability in the CD arm. RESULTS: Both DT and TT were significantly lower for the CD arm (15.1 ± 5.1 vs 23.5 ± 9.3, p < 0.0005 and 29.9 ± 14 vs 39.3 ± 13.5 min, p = 0.000374; respectively). The cost was also significantly lower using a CD versus SD. There was no inter-operator variability in the CD arm between 6 operators (p = 0.177 for DT and p = 0.304 for TT). No complications occurred in the SD arm. There were 3 vascular access site complications in the CD arm, all of which occurred early in the operator's experience. CONCLUSION: Coons dilator is an efficient and cost-effective method for vascular dilatation to facilitate Micra leadless pacemaker insertion. Rate of complications is low and expected to improve with greater experience.

To retrieve, or not to retrieve: System revisions with the Micra transcatheter pacemaker.

BACKGROUND: Early experience with leadless pacemakers has shown a low rate of complications. However, little is known about system revision in patients with these devices. OBJECTIVE: The purpose of this study was to describe the system revision experience with the Micra Transcatheter Pacing System (TPS). METHODS: Patients with implants from the Pre-market Micra Transcatheter Pacing Study and the Micra Transcatheter Pacing System Continued Access Study (N = 989) were analyzed and compared with 2667 patients with transvenous pacemakers (TVPs). Revisions included TPS retrieval/explant, repositioning, replacement, or electrical deactivation (with or without prior attempt at retrieval, generally followed by TVP implant) for any reason. Kaplan-Meier revision rates were calculated to account for varying follow-up duration and were compared using a Fine-Gray competing risk model. RESULTS: The actuarial rate for revision at 24 months postimplant was 1.4% for the TPS group (11 revisions in 10 patients), 75% (95% confidence interval 53%-87%; P < .001) lower than the 5.3% for the TVP group (123 revisions in 117 patients). TPS revisions occurred 5-430 days postimplant for elevated pacing thresholds, need for alternate therapy, pacemaker syndrome, and prosthetic valve endocarditis; none were due to device dislodgment or device-related infection. TPS was disabled and left in situ in 7 cases, 3 were retrieved percutaneously (range 9-406 days postimplant), and 1 was surgically removed during aortic valve surgery. CONCLUSION: The overall system revision rate for patients with TPS at 24 months was 1.4%, 75% lower than that for patients with TVPs. TPS was disabled and left in situ in 64% of revisions, and percutaneous retrieval was successful as late as 14 months postimplant.

Effect of pre-procedural interrupted apixaban on heparin anticoagulation during catheter ablation for atrial fibrillation: a prospective observational study.

PURPOSE: Effective intraprocedural anticoagulation is considered essential to minimize the risk of thromboembolism in catheter ablation (CA) of atrial fibrillation (AF). The effect of interrupted apixaban on intraprocedural heparin dosing requirements and levels of achieved anticoagulation with heparin has not been well studied. The purpose of the present study was to compare heparin administration and activated clotted times (ACTs) for patients undergoing CA for AF treated with interrupted apixaban before the procedure with patients on uninterrupted warfarin. METHODS: Consecutive patients undergoing CA for AF treated with interrupted apixaban or uninterrupted warfarin were prospectively enrolled. Heparin administration determined by a standard protocol and normalized to patient weight and procedure duration, as well as rapidity, and degree of anticoagulation with heparin (as measured by mean ACT, peak ACT, time to ACT ≥300 s, and time to ACT ≥350 s) were compared between the groups. RESULTS: Forty-eight patients were enrolled (25 apixaban and 23 warfarin). Heparin administered by bolus (51.3 ± 21.5 vs 27.8 ± 9.6 units/kg/h; p < 0.001) and mean heparin drip rate (25.3 ± 3.6 vs 20.7 ± 2.4 units/kg/h; p < 0.001) were significantly higher in the apixaban group compared to the warfarin group. Despite greater heparin administration, apixaban patients achieved a significantly lower mean ACT (332.3 ± 17.0 vs 384.5 ± 53.9; p < 0.001) and peak ACT (369.5 ± 22.6 vs 432.3 ± 75.8, p < 0.001) compared to the warfarin group. The time to ACT ≥350 s (66.7 ± 35.8 vs 26.9 ± 34.0; p < 0.001) was significantly longer for apixaban-treated patients. Outcome differences persisted after analysis using linear models and Cox proportional hazard regression with adjustment for propensity scores. CONCLUSIONS: A standard intraprocedural heparin protocol results in delayed and lower levels of anticoagulation as measured by the ACT for interrupted apixaban-treated patients in comparison to those on uninterrupted warfarin during CA of AF.

Suppression of canonical Wnt/beta-catenin signaling by nuclear plakoglobin recapitulates phenotype of arrhythmogenic right ventricular cardiomyopathy.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) is a genetic disease caused by mutations in desmosomal proteins. The phenotypic hallmark of ARVC is fibroadipocytic replacement of cardiac myocytes, which is a unique phenotype with a yet-to-be-defined molecular mechanism. We established atrial myocyte cell lines expressing siRNA against desmoplakin (DP), responsible for human ARVC. We show suppression of DP expression leads to nuclear localization of the desmosomal protein plakoglobin and a 2-fold reduction in canonical Wnt/beta-catenin signaling through Tcf/Lef1 transcription factors. The ensuing phenotype is increased expression of adipogenic and fibrogenic genes and accumulation of fat droplets. We further show that cardiac-restricted deletion of Dsp, encoding DP, impairs cardiac morphogenesis and leads to high embryonic lethality in the homozygous state. Heterozygous DP-deficient mice exhibited excess adipocytes and fibrosis in the myocardium, increased myocyte apoptosis, cardiac dysfunction, and ventricular arrhythmias, thus recapitulating the phenotype of human ARVC. We believe our results provide for a novel molecular mechanism for the pathogenesis of ARVC and establish cardiac-restricted DP-deficient mice as a model for human ARVC. These findings could provide for the opportunity to identify new diagnostic markers and therapeutic targets in patients with ARVC.