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.

Global LEADR pivotal trial results.

BACKGROUND: Implantable cardioverter-defibrillators last longer, and interest in reliable leads with targeted lead placement is growing. The OmniaSecure™ defibrillation lead is a novel small-diameter, catheter-delivered lead designed for targeted placement, based on the established SelectSecure SureScan MRI Model 3830 lumenless pacing lead platform. OBJECTIVE: This trial assessed safety and efficacy of the OmniaSecure defibrillation lead. METHODS: The worldwide LEADR pivotal clinical trial enrolled patients indicated for de novo implantation of a primary or secondary prevention implantable cardioverter-defibrillator/cardiac resynchronization therapy defibrillator, all of whom received the study lead. The primary efficacy end point was successful defibrillation at implantation per protocol. The primary safety end point was freedom from study lead-related major complications at 6 months. The primary efficacy and safety objectives were met if the lower bound of the 2-sided 95% credible interval was >88% and >90%, respectively. RESULTS: In total, 643 patients successfully received the study lead, and 505 patients have completed 12-month follow-up. The lead was placed in the desired right ventricular location in 99.5% of patients. Defibrillation testing at implantation was completed in 119 patients, with success in 97.5%. The Kaplan-Meier estimated freedom from study lead-related major complications was 97.1% at 6 and 12 months. The trial exceeded the primary efficacy and safety objective thresholds. There were zero study lead fractures and electrical performance was stable throughout the mean follow-up of 12.7 ± 4.8 months (mean ± SD). CONCLUSION: The OmniaSecure lead exceeded prespecified primary end point performance goals for safety and efficacy, demonstrating high defibrillation success and a low occurrence of lead-related major complications with zero lead fractures.

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.

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.

Real-World Evaluation of Magnetic Resonance Imaging in Patients With a Magnetic Resonance Imaging Conditional Pacemaker System: Results of 4-Year Prospective Follow-Up in 2,629 Patients.

OBJECTIVES: This global, multicenter, prospective study, initiated to meet U.S. Food and Drug Administration condition-of-approval requirements, evaluated the safety and efficacy of the Medtronic magnetic resonance imaging (MRI)-conditional pacing system when used in an MRI environment in routine clinical practice. The primary endpoint was MRI-related complications. The secondary endpoint was the cumulative change in pacing capture threshold (PCT) for patients undergoing multiple MRI scans. BACKGROUND: Large-scale, real-world evaluation of MRI in patients implanted with an MRI-conditional pacing system remains limited, with few published data for patients who undergo multiple MRI scans. METHODS: Patients were enrolled and followed up prospectively from the time of implantation. Evaluation of the pacemaker function was performed before and after MRI. The MRI-related complication-free rate was evaluated. Changes in electrical performance after each scan and cumulative changes over multiple scans were analyzed. RESULTS: In 81 centers, 2,629 patients were implanted with a complete SureScan pacing system (41.8% women, age 70.2 ± 12.5 years). A total of 526 patients (28.5%) received 872 clinically indicated MRI scans, including 58 thoracic scans. No MRI-related complications occurred during or after MRI, meeting the primary objective. Six (1%) MRI-related observations (atrial fibrillation, PCT increase, and chest symptoms) were reported. A total of 171 patients (32.5%) underwent 2 or more scans with no cumulative increase in PCT. CONCLUSIONS: This report constitutes the largest longitudinal MRI experience in patients implanted with an MRI-conditional pacing system. Results support the safety profile of the SureScan system and demonstrate for the first time that patients may safely undergo multiple MRI scans. (SureScan Post-Approval Study; NCT01299675).

Effect of chronic right ventricular apical pacing on left ventricular function.

The determinants of change in left ventricular (LV) ejection fraction (EF) over time in patients with impaired LV function at baseline have not been clearly established. Using a nuclear database to assess changes in LV function over time, we included patients with a baseline LVEF of 25% to 40% on a gated single-photon emission computed tomographic study at rest and only if second-gated photon emission computed tomography performed approximately 18 months after the initial study showed an improvement in LVEF at rest of > or =10 points or a decrease in LVEF at rest of > or =7 points. In all, 148 patients qualified for the EF increase group and 59 patients for the EF decrease group. LVEF on average increased from 33 +/- 4% to 51 +/- 8% in the EF increase group and decreased from 35 +/- 4% to 25 +/- 5% in the EF decrease group. The strongest multivariable predictor of improvement of LVEF was beta-blocker therapy (odds ratio 3.9, p = 0.002). The strongest independent predictor of LVEF decrease was the presence of a permanent right ventricular apical pacemaker (odds ratio 6.6, p = 0.002). Thus, this study identified beta-blocker therapy as the major independent predictor for improvement in LVEF of > or =10 points, whereas a permanent pacemaker (right ventricular apical pacing) was the strongest predictor of a LVEF decrease of > or =7 points.

Cardiovascular screening with electrocardiography and echocardiography in collegiate athletes.

BACKGROUND: Current guidelines for preparticipation screening of competitive athletes in the US include a comprehensive history and physical examination. The objective of this study was to determine the incremental value of electrocardiography and echocardiography added to a screening program consisting of history and physical examination in college athletes. METHODS: Competitive collegiate athletes at a single university underwent prospective collection of medical history, physical examination, 12-lead electrocardiography, and 2-dimensional echocardiography. Electrocardiograms (ECGs) were classified as normal, mildly abnormal, or distinctly abnormal according to previously published criteria. Eligibility for competition was determined using criteria from the 36(th) Bethesda Conference on Eligibility Recommendations for Competitive Athletes with Cardiovascular Abnormalities. RESULTS: In 964 consecutive athletes, ECGs were classified as abnormal in 334 (35%), of which 95 (10%) were distinctly abnormal. Distinct ECG abnormalities were more common in men than women (15% vs 6%, P<.001) as well as black compared with white athletes (18% vs 8%, P<.001). Echocardiographic and electrocardiographic findings initially resulted in exclusion of 9 athletes from competition, including 1 for long QT syndrome and 1 for aortic root dilatation; 7 athletes with Wolff-Parkinson-White patterns were ultimately cleared for participation. (Four received further evaluation and treatment, and 3 were determined to not need treatment.) After multivariable adjustment, black race was a statistically significant predictor of distinctly abnormal ECGs (relative risk 1.82, 95% confidence interval, 1.22-2.73; P=.01). CONCLUSIONS: Distinctly abnormal ECGs were found in 10% of athletes and were most common in black men. Noninvasive screening using both electrocardiography and echocardiography resulted in identification of 9 athletes with important cardiovascular conditions, 2 of whom were excluded from competition. These findings offer a framework for performing preparticipation screening for competitive collegiate athletes.