Catheter ablation for supraventricular tachycardia and health resource utilization and expenditures: A propensity-matched cohort study

BACKGROUND

Few data are available regarding temporal patterns of health resource utilization (HRU) and expenditures among patients undergoing catheter ablation for paroxysmal supraventricular tachycardia (PSVT). This study aimed to describe expenditures and HRU in patients with PSVT who underwent catheter ablation compared to a matched cohort of patients on medical therapy alone.

METHODS

Using a large US administrative database, we identified adult patients (age 18 to 65 years) with a new PSVT diagnosis between 2008 and 2016. Propensity-score matching was used to assemble a PSVT cohort treated with ablation or medical therapy alone (N = 2556). Longitudinal trends in HRU and expenditures in the 3-years preceding and following PSVT diagnosis were compared.

RESULTS

There were no significant differences in expenditures between groups except within the first year after PSVT diagnosis: $48,004 ablation vs. $17,560 medical therapy (p < 0.001). This difference was driven by procedural expenditures, where the mean cost of catheter ablation was $32,057 ± SD 26,737. In Years 2 and 3 post-ablation, HRU and expenditures decreased to the levels associated with the medical therapy group, although fewer ablation patients required any prescription for beta-blockers, calcium channel blockers, or anti-arrhythmic drugs (32% ablation vs. 42% medical therapy group, p < 0.001).

CONCLUSION

Catheter ablation reduces medication burden in PSVT, yet health resource use and expenditures were similar beyond 2 years post-ablation when compared to PSVT patients on medical therapy alone. Additional studies are required to better understand drivers of these sustained health expenditures, and barriers to achieving cost-savings for a potentially curative procedure.

Lead Extraction and Mortality Among Patients With Cardiac Implanted Electronic Device Infection

Importance

Complete hardware removal is a class I recommendation for cardiovascular implantable electronic device (CIED) infection, but practice patterns and outcomes remain unknown.

Objective

To quantify the number of Medicare patients with CIED infections who underwent implantation from 2006 to 2019 and lead extraction from 2007 to 2019 to analyze the outcomes in these patients in a nationwide clinical practice cohort.

Design, Setting, and Participants

This cohort study included fee-for-service Medicare Part D beneficiaries from January 1, 2006, to December 31, 2019, who had a de novo CIED implantation and a CIED infection more than 1 year after implantation. Data were analyzed from January 1, 2005, to December 31, 2019.

Exposure

A CIED infection, defined as (1) endocarditis or infection of a device implant and (2) documented antibiotic therapy.

Main Outcomes and Measures

The primary outcomes of interest were device infection, device extraction, and all-cause mortality. Time-varying multivariable Cox proportional hazards regression models were used to evaluate the association between extraction and survival.

Results

Among 1 065 549 patients (median age, 78.0 years [IQR, 72.0-84.0 years]; 50.9% male), mean (SD) follow-up was 4.6 (2.9) years after implantation. There were 11 304 patients (1.1%) with CIED infection (median age, 75.0 years [IQR, 67.0-82.0 years]); 60.1% were male, and 7724 (68.3%) had diabetes. A total of 2102 patients with CIED infection (18.6%) underwent extraction within 30 days of diagnosis. Infection occurred a mean (SD) of 3.7 (2.4) years after implantation, and 1-year survival was 68.3%. There was evidence of highly selective treatment, as most patients did not have extraction within 30 days of diagnosed infection (9202 [81.4%]), while 1511 (13.4%) had extraction within 6 days of diagnosis and 591 (5.2%) had extraction between days 7 and 30. Any extraction was associated with lower mortality compared with no extraction (adjusted hazard ratio [AHR], 0.82; 95% CI, 0.74-0.90; P < .001). Extraction within 6 days was associated with even lower risk of mortality (AHR, 0.69; 95% CI, 0.61-0.78; P < .001).

Conclusions and Relevance

In this study, a minority of patients with CIED infection underwent extraction. Extraction was associated with a lower risk of death compared with no extraction. The findings suggest a need to improve adherence to guideline-directed care among patients with CIED infection.

Incidence and Predictors of Relapse After Weaning Immune Suppressive Therapy in Cardiac Sarcoidosis

Cardiac sarcoidosis (CS) is a relapsing-remitting disease, and immune suppression (IS) is the mainstay of therapy. Predictors of relapse for patients with CS in remission are not well characterized. We assessed incidence of relapse in consecutive patients with CS treated with high-dose steroids and/or steroid-sparing agents (SSA) in our center from 2000 to 2020. Remission was defined as reaching maintenance therapy (no IS, SSA, and/or prednisone ≤5 mg/d) for ≥1 month. Relapse was defined as recurrence of CS syndrome requiring IS intensification: heart failure, ventricular arrhythmia, decrease in left ventricular ejection fraction, or increased disease burden on imaging. Among 68 patients, the mean age was 50.7±9.0 years; 25 (37%) were women, and 32 (47%) were Black. In total, 59 patients (87%) reached remission. Over a median follow-up of 39.5 months (interquartile range 17.6, 92.5), 28 (48%) relapsed. Greater percentage of late gadolinium enhancement (LGE) on pretreatment magnetic resonance imaging corresponded with increased likelihood of relapse (odds ratio 1.396 per 5% increase [95% confidence interval (CI) 1.04 to 1.88]; p = 0.028). LGE ≥11% predicted elevated risk of relapse (adjusted odds ratio 4.998 [1.34 to 18.64]; p = 0.017). Shorter time to relapse was observed with isolated CS (adjusted hazard ratio 4.084 [1.44,11.56]; p = 0.008) and LGE ≥11% (adjusted hazard ratio 3.007 [1.01, 8.98]; p = 0.049). Approximately 1 in 2 patients with CS in remission experienced relapse. Greater burden of LGE on cardiac magnetic resonance imaging and isolated CS are associated with greater risk of relapse. Future work is needed to refine risk stratification for relapse and to optimize surveillance strategies on the basis of the burden of disease.

Self-administered intranasal etripamil using a symptom-prompted, repeat-dose regimen for atrioventricular-nodal-dependent supraventricular tachycardia (RAPID): a multicentre, randomised trial

BACKGROUND

Etripamil is a fast-acting, intranasally administered calcium-channel blocker in development for on-demand therapy outside a health-care setting for paroxysmal supraventricular tachycardia. We aimed to evaluate the efficacy and safety of etripamil 70 mg nasal spray using a symptom-prompted, repeat-dose regimen for acute conversion of atrioventricular-nodal-dependent paroxysmal supraventricular tachycardia to sinus rhythm within 30 min.

METHODS

RAPID was a multicentre, randomised, placebo-controlled, event-driven trial, conducted at 160 sites in North America and Europe as part 2 of the NODE-301 study. Eligible patients were aged at least 18 years and had a history of paroxysmal supraventricular tachycardia with sustained, symptomatic episodes (≥20 min) as documented by electrocardiogram. Patients were administered two test doses of intranasal etripamil (each 70 mg, 10 min apart) during sinus rhythm; those who tolerated the test doses were randomly assigned (1:1) using an interactive response technology system to receive either etripamil or placebo. Prompted by symptoms of paroxysmal supraventricular tachycardia, patients self-administered a first dose of intranasal 70 mg etripamil or placebo and, if symptoms persisted beyond 10 min, a repeat dose. Continuously recorded electrocardiographic data were adjudicated, by individuals masked to patient assignment, for the primary endpoint of time to conversion of paroxysmal supraventricular tachycardia to sinus rhythm for at least 30 s within 30 min after the first dose, which was measured in all patients who administered blinded study drug for a confirmed atrioventricular-nodal-dependent event. Safety outcomes were assessed in all patients who self-administered blinded study drug for an episode of perceived paroxysmal supraventricular tachycardia. This trial is registered at ClinicalTrials.gov, NCT03464019, and is complete.

FINDINGS

Between Oct 13, 2020, and July 20, 2022, among 692 patients randomly assigned, 184 (99 from the etripamil group and 85 from the placebo group) self-administered study drug for atrioventricular-nodal-dependent paroxysmal supraventricular tachycardia, with diagnosis and timing confirmed. Kaplan-Meier estimates of conversion rates by 30 min were 64% (63/99) with etripamil and 31% (26/85) with placebo (hazard ratio 2·62; 95% CI 1·66-4·15; p<0·0001). Median time to conversion was 17·2 min (95% CI 13·4-26·5) with the etripamil regimen versus 53·5 min (38·7-87·3) with placebo. Prespecified sensitivity analyses of the primary assessment were conducted to test robustness, yielding supporting results. Treatment-emergent adverse events occurred in 68 (50%) of 99 patients treated with etripamil and 12 (11%) of 85 patients in the placebo group, most of which were located at the administration site and were mild or moderate, and all of which were transient and resolved without intervention. Adverse events occurring in at least 5% of patients treated with etripamil were nasal discomfort (23%), nasal congestion (13%), and rhinorrhea (9%). No serious etripamil-related adverse events or deaths were reported.

INTERPRETATION

Using a symptom-prompted, self-administered, initial and optional-repeat-dosing regimen, intranasal etripamil was well tolerated, safe, and superior to placebo for the rapid conversion of atrioventricular-nodal-dependent paroxysmal supraventricular tachycardia to sinus rhythm. This approach could empower patients to treat paroxysmal supraventricular tachycardia themselves outside of a health-care setting, and has the potential to reduce the need for additional medical interventions, such as intravenous medications given in an acute-care setting.

FUNDING

Milestone Pharmaceuticals.

Use of Ripple mapping to enhance localization and ablation of outflow tract premature ventricular contractions

INTRODUCTION

Accurate localization of septal outflow tract premature ventricular contractions (PVCs) is often difficult due to frequent mid-myocardial or protected origin. Compared with traditional activation mapping, CARTO Ripple mapping provides visualization of all captured electrogram data without assignment of a specific local activation time and thus may enhance PVC localization.

METHODS

Electroanatomic maps for consecutive catheter ablation procedures for septal outflow tract PVCs (July 2018-December 2020) were analyzed. For each PVC, we identified the earliest local activation point (EA), defined by the point of maximal -dV/dt in a simultaneously recorded unipolar electrogram, and the earliest Ripple signal (ERS), defined as the earliest point at which three grouped simultaneous Ripple bars appeared in late diastole. Immediate success was defined as full suppression of the clinical PVC.

RESULTS

Fifty-seven unique PVCs in 55 procedures were included. When ERS and EA were in the same chamber (RV, LV, or CS), the odds ratio for the successful procedure was 13.1 (95% confidence interval [CI] 2.2-79.9, p = .005). Discordance between sites was associated with a higher likelihood of needing multi-site ablation (odds ratio [OR] 7.9 [1.4-4.6; p = .020]). Median EA-ERS distance in successful versus unsuccessful cases was 4.6 mm (interquartile range 2.9-8.5) versus 12.5 mm (7.8-18.5); (p = .020).

CONCLUSION

Greater EA-ERS concordance was associated with higher odds of single-site PVC suppression and successful septal outflow tract PVC ablation. Visualization of complex signals via automated Ripple mapping may offer rapid localization information complementary to local activation mapping for PVCs of mid-myocardial origin.

Direct Oral Anticoagulants Versus Warfarin Across the Spectrum of Kidney Function: Patient-Level Network Meta-Analyses From COMBINE AF

BACKGROUND

There is uncertainty surrounding the use of direct oral anticoagulants (DOACs) in patients with kidney dysfunction.

METHODS

Using the COMBINE AF (A Collaboration Between Multiple Institutions to Better Investigate Non-Vitamin K Antagonist Oral Anticoagulant Use in Atrial Fibrillation) database (data from RE-LY [Randomized Evaluation of Long-term Anticoagulation Therapy], ROCKET AF [Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation], ARISTOTLE [Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation], and ENGAGE AF-TIMI 48 [Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48]), we performed an individual patient-level network meta-analysis to evaluate the safety and efficacy of DOACs versus warfarin across continuous creatinine clearance (CrCl). A multivariable Cox model including treatment-by-CrCl interaction with random effects was fitted to estimate hazard ratios for paired treatment strategies (standard-dose DOAC, lower-dose DOAC, and warfarin). Outcomes included stroke and systemic embolism (S/SE), major bleeding, intracranial hemorrhage (ICH), and death.

RESULTS

Among 71 683 patients (mean age, 70.6±9.4 years; 37.3% female; median follow-up, 23.1 months), the mean CrCl was 75.5±30.5 mL/min. The incidence of S/SE, major bleeding, ICH, and death increased significantly with worsening kidney function. Across continuous CrCl values down to 25 mL/min, the hazard of major bleeding did not change for patients randomized to standard-dose DOACs compared with those randomized to warfarin (Pinteraction=0.61). Compared with warfarin, standard-dose DOAC use resulted in a significantly lower hazard of ICH at CrCl values <122 mL/min, with a trend for increased safety with DOAC as CrCl decreased (6.2% decrease in hazard ratio per 10-mL/min decrease in CrCl; Pinteraction=0.08). Compared with warfarin, standard-dose DOAC use resulted in a significantly lower hazard of S/SE with CrCl <87 mL/min, with a significant treatment-by-CrCl effect (4.8% decrease in hazard ratio per 10-mL/min decrease in CrCl; Pinteraction=0.01). The hazard of death was significantly lower with standard-dose DOACs for patients with CrCl <77 mL/min, with a trend toward increasing benefit with lower CrCl (2.1% decrease in hazard ratio per 10-mL/min decrease in CrCl; Pinteraction=0.08). Use of lower-dose rather than standard-dose DOACs was not associated with a significant difference in incident bleeding or ICH in patients with reduced kidney function but was associated with a higher incidence4 of death and S/SE.

CONCLUSIONS

Standard-dose DOACs are safer and more effective than warfarin down to a CrCl of at least 25 mL/min. Lower-dose DOACs do not significantly lower the incidence of bleeding or ICH compared with standard-dose DOACs but are associated with a higher incidence of S/SE and death. These findings support the use of standard-dose DOACs over warfarin in patients with kidney dysfunction.

Efficacy and Safety of Adjunctive and Primary Use of the TightRail Mechanical Cutting Sheath for Lead Extraction

BACKGROUND

Rotational cutting tools are increasingly used in transvenous lead extraction. There are limited data on their safety and efficacy, particularly when used adjunctively for stalled progression. The aim of this study was to evaluate the utilization, safety, and effectiveness of mechanical rotational cutting tools for transvenous lead extraction.

METHODS

Patients undergoing transvenous lead extraction at a single tertiary center (April 2015 to January 2021, n=586) were included in this retrospective analysis. The study characterized the 251 patients (42.8%) whose cases involved the TightRail mechanical cutting tool.

RESULTS

Among 251 patients, 526 leads were extracted and TightRail was used for 70.5%. The TightRail was used adjunctively with the laser for 65.2% of leads, 97.8% of the time as the second tool after stalled progression. Using a multivariable logistic regression model, we found that active-fixation leads (odds ratio, 2.78 [95% CI, 1.62-4.78]; P=0.0002), dual-coil leads (odds ratio, 3.39 [95% CI, 1.87-6.16]; P<0.0001), and lead dwell time (odds ratio, 1.16 [95% CI for 1-year increase, 1.11-1.21]; P<0.0001) were factors independently associated with adjunctive TightRail use. Stalled progression requiring TightRail occurred most often in the innominate vein and superior vena cava (59.3%). The clinical success rate was 96.8%, and the rate of major adverse events was 2.8%. Only 1 major adverse event was observed during TightRail use.

CONCLUSIONS

Rotational cutting with TightRail was used in 42.8% of transvenous lead extractions, predominantly in an adjunctive manner after stalled laser progression in the innominate vein and superior vena cava, and more frequently for dual-coil and leads with longer dwell times. Adjunctive TightRail use carries a low risk of major complications.

Early Lead Extraction for Infected Implanted Cardiac Electronic Devices: JACC Review Topic of the Week

Infection remains a serious complication associated with the cardiac implantable electronic devices (CIEDs), leading to substantial clinical and economic burden globally. This review assesses the burden of cardiac implantable electronic device infection (CIED-I), evidence for treatment recommendations, barriers to early diagnosis and appropriate therapy, and potential solutions. Multiple clinical practice guidelines recommended complete system and lead removal for CIED-I when appropriate. CIED extraction for infection has been consistently reported with high success, low complication, and very low mortality rates. Complete and early extraction was associated with significantly better clinical and economic outcome compared with no or late extraction. However, significant gaps in knowledge and poor recommendation compliance have been reported. Barriers to optimal management may include diagnostic delay, knowledge gaps, and limited access to expertise. A multipronged approach, including education of all stakeholders, a CIED-I alert system, and improving access to experts, could help bring paradigm shift in the treatment of this serious condition.

Apixaban for Patients With Atrial Fibrillation on Hemodialysis: A Multicenter Randomized Controlled Trial

BACKGROUND

There are no randomized data evaluating the safety or efficacy of apixaban for stroke prevention in patients with end-stage kidney disease on hemodialysis and with atrial fibrillation (AF).

METHODS

The RENAL-AF trial (Renal Hemodialysis Patients Allocated Apixaban Versus Warfarin in Atrial Fibrillation) was a prospective, randomized, open-label, blinded-outcome evaluation (PROBE) of apixaban versus warfarin in patients receiving hemodialysis with AF and a CHA2DS2-VASc score ≥2. Patients were randomly assigned 1:1 to 5 mg of apixaban twice daily (2.5 mg twice daily for patients ≥80 years of age, weight ≤60 kg, or both) or dose-adjusted warfarin. The primary outcome was time to major or clinically relevant nonmajor bleeding. Secondary outcomes included stroke, mortality, and apixaban pharmacokinetics. Pharmacokinetic sampling was day 1, day 3, and month 1.

RESULTS

From January 2017 through January 2019, 154 patients were randomly assigned to apixaban (n=82) or warfarin (n=72). The trial stopped prematurely because of enrollment challenges. Time in therapeutic range (international normalized ratio, 2.0-3.0) for warfarin-treated patients was 44% (interquartile range, 23%-59%). The 1-year rates for major or clinically relevant nonmajor bleeding were 32% and 26% in apixaban and warfarin groups, respectively (hazard ratio, 1.20 [95% CI, 0.63-2.30]), whereas 1-year rates for stroke or systemic embolism were 3.0% and 3.3% in apixaban and warfarin groups, respectively. Death was the most common major event in the apixaban (21 patients [26%]) and warfarin (13 patients [18%]) arms. The pharmacokinetic substudy enrolled the target 50 patients. Median steady-state 12-hour area under the curve was 2475 ng/mL×h (10th to 90th percentiles, 1342-3285) for 5 mg of apixaban twice daily and 1269 ng/mL×h (10th to 90th percentiles, 615-1946) for 2.5 mg of apixaban twice daily. There was substantial overlap between minimum apixaban blood concentration, 12-hour area under the curve, and maximum apixaban blood concentration for patients with and without a major or clinically relevant nonmajor bleeding event.

CONCLUSIONS

There was inadequate power to draw any conclusion regarding rates of major or clinically relevant nonmajor bleeding comparing apixaban and warfarin in patients with AF and end-stage kidney disease on hemodialysis. Clinically relevant bleeding events were ≈10-fold more frequent than stroke or systemic embolism among this population on anticoagulation, highlighting the need for future randomized studies evaluating the risks versus benefits of anticoagulation among patients with AF and end-stage kidney disease on hemodialysis.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02942407.

Residual stroke risk despite oral anticoagulation in patients with atrial fibrillation

Background

Oral anticoagulation (OAC) reduces the risk of thromboembolic events in patients with atrial fibrillation (AF); however, thromboembolism (TE) still can occur despite OAC. Factors associated with residual risk for stroke, systemic embolism, or transient ischemic attack events despite OAC have not been well described.

Objective

The purpose of this study was to evaluate the residual risk of thromboembolic events in patients with AF despite OAC.

Methods

A total of 18,955 patients were analyzed in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF I and II) using multivariable Cox proportional hazard modeling. Mean age was 72 ± 10.7, and 42% were women. There were 451 outcome events.

Results

The risk of TE despite OAC increased with CHA₂DS₂-VASc score: 0.76 (95% confidence interval [CI] 0.63-0.92) events per 100 patient-years for CHA₂DS₂-VASc score <4 vs 2.01 (95% CI 1.81-2.24) events per 100-patient years for CHA₂DS₂-VASc score >4. Factors associated with increased risk were previous stroke or transient ischemic attack (hazard ratio [HR] 2.87; 95% CI 2.30-3.59; P <.001), female sex (HR 1.52; 95% CI 1.24-1.86; P <.001), hypertension (HR 1.50; 95% CI 1.09-2.06; P = .01), and permanent AF (HR 1.47; 95% CI 1.12-1.94; P = .001). When transient ischemic attack was excluded, the results were similar, but permanent AF was no longer significantly associated with thromboembolic events.

Conclusion

Patients with AF have a residual risk of TE with increasing CHA₂DS₂-VASc score despite OAC. Key risk markers include previous stroke/transient ischemic attack, female sex, hypertension, and permanent AF.

Left Atrial Appendage Occlusion Versus Oral Anticoagulation in Atrial Fibrillation : A Decision Analysis

BACKGROUND

Left atrial appendage occlusion (LAAO) is a potential alternative to oral anticoagulants in selected patients with atrial fibrillation (AF). Compared with anticoagulants, LAAO decreases major bleeding risk, but there is uncertainty regarding the risk for ischemic stroke compared with anticoagulation.

OBJECTIVE

To determine the optimal strategy for stroke prevention conditional on a patient's individual risks for ischemic stroke and bleeding.

DESIGN

Decision analysis with a Markov model.

DATA SOURCES

Evidence from the published literature informed model inputs.

TARGET POPULATION

Women and men with nonvalvular AF and without prior stroke.

TIME HORIZON

Lifetime.

PERSPECTIVE

Clinical.

INTERVENTION

LAAO versus warfarin or direct oral anticoagulants (DOACs).

OUTCOME MEASURES

The primary end point was clinical benefit measured in quality-adjusted life-years.

RESULTS OF BASE-CASE ANALYSIS

The baseline risks for stroke and bleeding determined whether LAAO was preferred over anticoagulants in patients with AF. The combined risks favored LAAO for higher bleeding risk, but that benefit became less certain at higher stroke risks. For example, at a HAS-BLED score of 5, LAAO was favored in more than 80% of model simulations for CHA₂DS₂-VASc scores between 2 and 5. The probability of LAAO benefit in QALYs (>80%) at lower bleeding risks (HAS-BLED score of 0 to 1) was limited to patients with lower stroke risks (CHA₂DS₂-VASc score of 2). Because DOACs carry lower bleeding risks than warfarin, the net benefit of LAAO is less certain than that of DOACs.

RESULTS OF SENSITIVITY ANALYSIS

Results were consistent using the ORBIT bleeding score instead of the HAS-BLED score, as well as alternative sources for LAAO clinical effectiveness data.

LIMITATION

Clinical effectiveness data were drawn primarily from studies on the Watchman device.

CONCLUSION

Although LAAO could be an alternative to anticoagulants for stroke prevention in patients with AF and high bleeding risk, the overall benefit from LAAO depends on the combination of stroke and bleeding risks in individual patients. These results suggest the need for a sufficiently low stroke risk for LAAO to be beneficial. The authors believe that these results could improve shared decision making when selecting patients for LAAO.

PRIMARY FUNDING SOURCE

None.

Syncope Recurrence and Downstream Diagnostic Testing after Insertable Cardiac Monitor Placement for Syncope

Despite advances in syncope evaluation strategies and risk stratification, the high cost of syncope is largely driven by extensive and often repetitive testing. This analysis of a large deidentified US claims database compared the use of diagnostic tests, therapeutic procedures, and the recurrence rate of acute syncope events before and after placement of an insertable cardiac monitor (ICM) in syncope patients. The patients had a minimum of 1 year of continuous enrollment before and 2 years after ICM placement. Among 2140 patients identified, a statistically significant reduction in the use of 14 out of 18 tests was observed during follow-up compared with pre-ICM testing. During the 2-year follow-up, 28.3% of patients underwent cardiac therapeutic interventions after a median of 127 days. Significantly fewer patients experienced acute syncope events during the 1st and 2nd years of ICM follow-up compared with the 1-year pre-ICM period, and the frequency of events per patient also decreased. In conclusion, reductions in diagnostic testing and acute syncope events were observed after ICM placement in a large real-world cohort of unexplained syncope patients. Further studies are needed to prospectively assess the impact of ICM vs. short-term monitoring on patient outcomes and healthcare utilization.

Effect of Mailing Educational Material to Patients With Atrial Fibrillation and Their Clinicians on Use of Oral Anticoagulants: A Randomized Clinical Trial

IMPORTANCE

Only about half of patients with atrial fibrillation (AF) who are at increased risk for stroke are treated with an oral anticoagulant (OAC), despite guideline recommendations for their use. Educating patients with AF about prevention of stroke with OACs may enable them as agents of change to initiate OAC treatment.

OBJECTIVE

To determine whether an educational intervention directed to patients and their clinicians stimulates the use of OACs in patients with AF who are not receiving OACs.

DESIGN, SETTING, AND PARTICIPANTS

The Implementation of a Randomized Controlled Trial to Improve Treatment With Oral Anticoagulants in Patients With Atrial Fibrillation (IMPACT-AFib) trial was a prospective, multicenter, open-label, pragmatic randomized clinical trial conducted from September 25, 2017, to May 1, 2019, embedded in health plans that participate in the US Food and Drug Administration's Sentinel System. It used the distributed database comprising health plan members to identify eligible patients, their clinicians, and outcomes. IMPACT-AFib enrolled patients with AF, a CHA2DS2-VASc (cardiac failure or dysfunction, hypertension, age 65-74 [1 point] or ≥75 years [2 points], diabetes, and stroke, transient ischemic attack or thromboembolism [2 points]-vascular disease, and sex category [female]) score of 2 or more, no evidence of OAC prescription dispensing in the preceding 12 months, and no hospitalization-related bleeding event within the prior 6 months.

INTERVENTIONS

Randomization to a single mailing of patient and/or clinician educational materials vs control.

MAIN OUTCOMES AND MEASURES

Analysis was performed on a modified intention-to-treat basis. The primary end point was the proportion of patients with at least 1 OAC prescription dispensed or at least 4 international normalized ratio test results within 1 year of the intervention.

RESULTS

Among 47 333 patients, there were 24 909 men (52.6%), the mean (SD) age was 77.9 (9.7) years, mean (SD) CHA2DS2-VASc score was 4.5 (1.7), 22 404 patients (47.3%) had an ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) bleeding risk score of 5 or more, and 8890 patients (18.8%) had a history of hospitalization for bleeding. There were 2328 of 23 546 patients (9.9%) in the intervention group with initiation of OAC at 1 year compared with 2330 of 23 787 patients (9.8%) in the control group (adjusted OR, 1.01 [95% CI, 0.95-1.07]; P = .79).

CONCLUSIONS AND RELEVANCE

Among a large population with AF with a guideline indication for OACs for stroke prevention who were randomized to a mailed educational intervention or to usual care, there was no clinically meaningful, numerical, or statistically significant difference in rates of OAC initiation. More-intensive interventions are needed to try and address the public health issue of underuse of anticoagulation for stroke prevention among patients with AF.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03259373.

Leadless Pacemaker Implantation after Lead Extraction for Cardiac Implanted Electronic Device Infection

BACKGROUND

Cardiac implanted electronic device (CIED) pocket and systemic infection remain common complications with traditional CIEDs and are associated with high morbidity and mortality. Leadless pacemakers may be an attractive pacing alternative for many patients following complete hardware removal for a CIED infection by eliminating surgical pocket-related complications as well as lower risk of recurrent complications.

OBJECTIVE

To describe use and outcomes associated with leadless pacemaker implantation following extraction of a prior CIED system due to infection.

METHODS

Patient characteristics and post-procedural outcomes were described in patients who underwent leadless pacemaker implantation at Duke University Hospital between November 11, 2014 and November 18, 2019, following CIED infection and device extraction. Outcomes of interest included procedural complications, pacemaker syndrome, need for system revision, and recurrent infection.

RESULTS

Among 39 patients, the mean age was 71 ±17 years, 31% were women, and the most frequent primary pacing indication was complete heart block (64.1%) with 9 (23.1%) patients being pacemaker dependent at the time of Micra implantation. The primary organism implicated in the CIED infection was Staphylococcus aureus (43.6%). Nine of the 39 patients had a leadless pacemaker implanted before or on the same day as their extraction procedure, and the remaining 30 patients had a leadless pacemaker implanted after their extraction procedure. During the mean follow-up time (mean 24.8 ± 14.7 months) following the leadless pacemaker implantation, there were a total of 3 major complications: 1 groin hematoma, 1 femoral arteriovenous fistula, and 1 case of pacemaker syndrome. No patients had evidence of recurrent CIED infection after leadless pacemaker implantation.

CONCLUSIONS

Despite a prior CIED infection and an elevated risk of recurrent infection, there was no evidence of CIED infection with a mean follow up of over 2 years following leadless pacemaker implantation at or after CIED system removal. Larger studies with longer follow-up are required to determine if there is a long-term advantage to implanting a leadless pacemaker versus a traditional pacemaker following temporary pacing when needed during the peri-extraction period in patients with a prior CIED infection. This article is protected by copyright. All rights reserved.

Atrial Branch Coronary Artery Stenosis as a Mechanism for Atrial Fibrillation

BACKGROUND

The etiology of atrial fibrillation (AF) is multifactorial and incompletely understood.

OBJECTIVE

Evaluate the association between coronary artery disease (CAD) affecting atrial tissue and AF.

METHODS

Patients from a single center with obstructive CAD during cardiac catheterization (1/12007-12/1/2013) were included in a matched case-control analysis, based on the presence or absence of new-onset AF within 12 months post-catheterization. Quantitative measurements of stenosis severity were performed for sinoatrial (SA) nodal artery, atrioventricular (AV) nodal artery, and right intermediate atrial artery (RIAA), as well as the right coronary, left circumflex, and left anterior descending proximal to the take-off for each atrial-level artery. A multivariable logistic regression model identified factors associated with AF.

RESULTS

Among 1,794 patients, 115 (6%) developed AF within 1-year post-catheterization. The matched cohort included 110 patients with and 110 patients without AF within 12 months post-catheterization. Higher odds of AF at 1 year were associated with increasing lesion stenosis severity in the RIAA (OR 1.41 per 10% increase >50%, 95% CI 1.01-1.97, p=0.047) and AV nodal artery (OR 1.58 per 10% increase >50%, 95% CI 1.00-2.49, p=0.050). Odds of AF diagnosis during the year post-catheterization increased with the number of atrial arteries with >50% lesion (OR 1.53 for each additional artery, 95% CI 1.08-2.15, p=0.015).

CONCLUSIONS

Among patients with obstructive CAD, disease of the AV nodal artery and RIAA, as well as higher burden of CAD within all arteries supplying blood flow to the atrial myocardium were associated with higher odds of new-onset AF at 1 year.

Cases of Azygous Coil Extraction

Background

Procedural and clinical outcomes of patients undergoing extraction or removal of azygous coils are not well characterized.

Objective

Evaluate outcomes in patients who undergo device extraction with an azygous coil in situ.

Methods

Patients undergoing extraction with an azygous coil in situ between May 2015 and January 2021 were included in this retrospective single-center analysis. Outcomes included procedural success, use of laser and mechanical cutting tools during the procedure, procedural complications, and mortality.

Results

We identified 2 patients undergoing device extraction with an azygous coil in situ with a dwell time greater than 12 months. The patients were male, aged 73 and 83 years. Both had a history of hypertension, atrial fibrillation, heart failure (ejection fractions <15% and 20%), and cardiomyopathy (nonischemic and ischemic), and presented with an infection (case 1 with a single-chamber ICD and Staphylococcus aureus bacteremia, case 2 with a cardiac resynchronization therapy defibrillator pocket infection). The mean dwell time of all 6 leads extracted was 6.43 years (range 1.33–12.63 years), and the 2 azygous coils had dwell times of 1.33 and 6.04 years. In case 1, the azygous coil was inferior to the cardiac silhouette, while in case 2 it was superior. A 14F laser sheath was employed to remove both azygous coils. Both extractions were a complete procedural success in which all leads were removed completely without intraoperative complications.

Conclusion

These cases demonstrate the variable courses of azygous coils, provide proof of concept that they can be removed safely, and illustrate that azygous coils can be removed with the same techniques that are commonly used to remove other types of leads.

Optimizing mechanically sensed atrial tracking in patients with atrioventricular-synchronous leadless pacemakers: A single-center experience

Background

Atrioventricular (AV)-synchronous single-chamber leadless pacing using a mechanical atrial sensing algorithm produced high AV synchrony in clinical trials, but clinical practice experience with these devices has not yet been described.

Objective

To describe pacing outcomes and programming changes with AV-synchronous leadless pacemakers in clinical practice.

Methods

Consecutive patients without persistent atrial fibrillation who received an AV-synchronous leadless pacemaker and completed follow-up between February 2020 and April 2021 were included. We evaluated tracking index (atrial mechanical sense followed by ventricular pace [AM-VP] divided by total VP), total AV synchrony (sum of AM-ventricular sense [AM-VS], AM-VP, and AV conduction mode switch), use of programming optimization, and improvement in AV synchrony after optimization.

Results

Fifty patients met the inclusion criteria. Mean age was 69 ± 16.8 years, 24 (48%) were women, 24 (48%) had complete heart block, and 17 (34%) required ≥50% pacing. Mean tracking index was 41% ± 34%. Thirty-five patients (70%) received ≥1 programming change. In 36 patients with 2 follow-up visits, tracking improved by +9% ± 28% (P value for improvement = .09) and +18% ± 19% (P = .02) among 15 patients with complete heart block. Average total AV synchrony increased from 89% [67%, 99%] to 93% [78%, 100%] in all patients (P = .22), from 86% [52%, 98%] to 97% [82%, 99%] in those with complete heart block (P = .04), and from 73% [52%, 80%] to 78% [70%, 85%] in those with ≥50% pacing (P = .09).

Conclusion

In patients with AV-synchronous leadless pacemakers, programming changes are frequent and are associated with increased atrial tracking and increased AV synchrony in patients with complete heart block.

Comparative outcomes of Riata and Fidelis lead management strategies: Results from the NCDR-ICD Registry

BACKGROUND

The Medtronic Sprint Fidelis® and Abbott Riata®/Riata ST® leads are at risk of failure and are subject to FDA recall. Comparative risks of various lead management strategies during elective generator change in a multi-center population are unknown. We aim to describe patients with functional, recalled ICD leads undergoing elective generator replacement and report outcomes according to lead management strategies.

METHODS

Using data from the NCDR ICD Registry, patients with a functioning Riata® or Fidelis® lead undergoing generator replacement are described according to lead management: reuse, abandon/replace, and extract/replace. Adjusted rates of death and pre-discharge complications are reported.

RESULTS

There were 13,144 generator replacement procedures involving a functioning, non-infected Riata® or Fidelis® lead (extraction n = 414, abandonment n = 427). Extraction patients were younger (mean 58 vs. 67 years) with fewer comorbidities than the reuse group. Maximum lead dwell time was similar between groups with average 94, 90, and 99 months in the extraction, abandonment, and reuse groups, respectively. In-hospital complications or mortality were more common in the extraction group (10.14%, 4.35%) compared with abandonment (1.64%, 0.47%) and reuse (0.22%, 0.07%). Compared with reuse, the adjusted odds of death or pre-discharge complication were significantly higher in the extraction group (OR 7.77 95% CI 2.42-24.95, p < .001) but not the abandonment group (OR 1.70 95% CI 0.52-5.61, p = .38).

CONCLUSIONS

In this real-world population, extraction of functional recalled ICD leads was associated with significant risk of in-hospital mortality and complications. Additional work is needed to clarify whether longer term outcomes balance these peri-procedural risks.

Shared decision-making in atrial fibrillation: patient-reported involvement in treatment decisions

AIMS

To determine the extent of shared decision-making (SDM), during selection of oral anticoagulant (OAC) and rhythm control treatments, in patients with newly diagnosed atrial fibrillation (AF).

METHODS AND RESULTS

We evaluated survey data from 1006 patients with new-onset AF enrolled at 56 US sites participating in the SATELLITE substudy of the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT II). Patients completed surveys at enrolment and at 6-month follow-up. Patients were asked about who made their AF treatment decisions. Shared decision-making was classified as one that the patient felt was an autonomous decision or a shared decision with their healthcare provider (HCP). Approximately half of patients reported that their OAC treatment decisions were made entirely by their HCP. Compared with those reporting no SDM, patients reporting SDM for OAC were more often female (47.2% vs. 38.4%), while patients reporting SDM for rhythm control were more often male (62.2% vs. 57.6%). The most important factors cited by patients during decision-making for OAC were reducing stroke and bleeding risk, and their HCP's recommendations. After adjustment, patients with self-reported understanding of OAC, and rhythm control options, had higher odds of having participated in SDM [odds ratio (OR) 2.54, confidence interval (CI): 1.75-3.68 and OR 2.36, CI: 1.50-3.71, both P ≤ 0.001, respectively].

CONCLUSION

Shared decision-making is not widely implemented in contemporary AF practice. Patient understanding about available therapeutic options is associated with a more than a two-fold higher likelihood of SDM, and may be a potential target for future interventions.

Prevalence and incidence of patients with paroxysmal supraventricular tachycardia in the United States

BACKGROUND

Paroxysmal supraventricular tachycardia (PSVT) encompasses a range of heart rhythm disorders leading to rapid heart rates. By virtue of its episodic nature, diagnosing PSVT is difficult and estimating incidence and prevalence on a population level is challenging. The objective of this study was to estimate the incidence and prevalence of PSVT in the United States (US) in contemporary practice.

METHODS AND RESULTS

An observational retrospective longitudinal study using claims, enrollment, and demographic data from the IBM MarketScan® Commercial Research database (age < 65) and the Medicare Limited Data Set (age ≥ 65) from 2008 to 2016. Patients with a PSVT diagnosis code (ICD-9: 427.0; ICD-10: I47.1) on ≥2 outpatient, ≥1 emergency room, or ≥1 inpatient visit were considered as having PSVT. Patients with atrial fibrillation/atrial flutter (AF/AFL) were excluded from the initial analysis given the potential for misclassification. Incidence was estimated by assessing diagnoses made during year 5 of continuous enrollment. Finally, a sensitivity analysis was performed by including patients with both PSVT and AF/AFL diagnoses. Period prevalence and incidence rate were estimated to be 332.9 (323.2-342.9) and 57.8 (52.8-63.3) per 100 000 individuals, respectively, when excluding patients with AF/AFL. Projected to the 2018 US Census, prevalence and incidence are 1.26 million (1.21-1.30 million) and 188,981 (172,891-206,943), respectively. Including patients with AF/AFL, the prevalence may increase to 479.7 (467.9-491.8) with an incidence of 93.4 (86.9-100.5) per 100 000 individuals or a prevalence of 2.06 million (2.01-2.12 million).

CONCLUSIONS

Approximately 1 in 300 people in the US had PSVT with the highest rates in older and female patients.

Electrical storm in patients with left ventricular assist devices: Risk factors, incidence, and impact on survival

BACKGROUND

Ventricular arrhythmias (VAs) and electrical storm (ES) are recognized complications following left ventricular assist device (LVAD) implantation; however, their association with long term-outcomes remains poorly understood.

OBJECTIVE

The purpose of this study was to describe the clinical impact of ES in a population of patients undergoing LVAD implantation at a quaternary care center in the United States.

METHODS

This was an observational retrospective study of patients undergoing LVAD implantation from 2009 to 2020 at Duke University Hospital. The incidence of ES (≥3 sustained VA episodes over a 24-hour period without an identifiable reversible cause) was determined from patient records. Risk factors for ES were identified using multivariable Cox proportional hazards modeling.

RESULTS

Among 730 patients undergoing LVAD implant, 78 (10.7%) developed ES at a median of 269 (interquartile range [IQR] 7-766) days following surgery. Twenty-seven patients (34.6%) developed ES within 30 days, while 51 (65.4%) presented with ES at a median 639 (IQR 281-1017) days after implant. Following ES, 41% of patients died within 1 year. Patients who developed ES were more likely to have a history of VAs, ventricular tachycardia ablation, antiarrhythmic drug use, and perioperative mechanical circulatory support around the time of LVAD implant than patients without ES.

CONCLUSION

ES occurs in 1 in 10 patients after LVAD and is associated with higher mortality. Risk factors for ES include a history of VAs, VT ablation, antiarrhythmic drug use, and perioperative mechanical circulatory support. Optimal management of ES surrounding LVAD implant, including escalation of medical therapy, catheter ablation, or adjunctive sympatholytic therapies, remains uncertain.

Periprocedural Risk and Survival Associated With Implantable Cardioverter-Defibrillator Placement in Older Patients With Advanced Heart Failure

Importance

Little is known about the utilization rates and outcomes of implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy defibrillator (CRT-D) placement among patients with advanced heart failure (HF).

Objective

To examine utilization rates, patient characteristics, and outcomes of ICD and CRT-D placements among patients with advanced HF.

Design, Setting, and Participants

This cohort study was a post hoc analysis of 81 492 Medicare fee-for-service beneficiaries enrolled in the National Cardiovascular Data Registry ICD Registry between January 2010 and December 2014. Inclusion criteria were patients who had received an HF diagnosis, had a left ventricular ejection fraction of 35% or lower, and showed evidence of advanced HF, which was defined as New York Heart Association (NYHA) class IV symptoms, inotrope use within the last 60 days, left ventricular assist device in situ, or orthotopic heart transplant listing. The comparator group included patients with NYHA class II and no HF hospitalization within the last 12 months, no left ventricular assist device, no orthotopic heart transplant listing, and no current or recent inotrope use. All eligible patients underwent first-time ICD or CRT-D placement for primary prevention of sudden cardiac death. Data were analyzed from January 2010 to December 2014.

Main Outcomes and Measures

All-cause mortality and periprocedural complications.

Results

Of 81 492 Medicare patients, 3343 had advanced HF (4.1%) and 19 424 were in the comparator group (23.8%). Among the advanced HF population, the mean (SD) age of patients was 74 (9) years, and patients were predominantly white individuals (81.5%) and men (71.1%). The all-cause mortality rate at 30 days was 3.1% (95% CI, 2.6%-3.8%) in the advanced HF group vs 0.5% (0.4%-0.6%) in the comparator group (P < .001). In the advanced HF population, the aggregate in-hospital periprocedural complication rate was 3.74% (95% CI, 3.12%-4.44%) vs 1.10% (95% CI, 0.95%-1.25%) in the comparator group (P < .001). Most adverse events in this group were in-hospital fatality (1.82%; 95% CI, 1.40%-2.34%) and resuscitated cardiac arrest (1.05%; 95% CI, 0.73%-1.45%). Patients with NYHA class IV (hazard ratio, 1.40; 95% CI, 1.02-1.93; P = .04), ischemic heart disease (hazard ratio, 1.24; 95% CI, 1.04-1.48; P = .02), or diabetes (hazard ratio, 1.17; 95% CI, 1.04-1.33; P = .01) had a higher risk of death.

Conclusions and Relevance

Among patients undergoing ICD or CRT-D placement for primary prevention of sudden cardiac death, only a small proportion had advanced HF. These patients experienced clinically important periprocedural complication rates associated with in-hospital death and cardiac arrest relative to patients with nonadvanced HF.

Implantable Cardioverter Defibrillator Utilization and Mortality Among Patients ≥65 Years of Age With a Low Ejection Fraction After Coronary Revascularization

The purpose of this analysis was to assess implantable cardioverter-defibrillator (ICD) utilization and its association with mortality among patients ≥65 years of age after coronary revascularization. Patients in the National Cardiovascular Database Registry Chest Pain-Myocardial Infarction (MI) Registry who presented with MI from January 2, 2009 to December 31, 2016, had a left ventricular ejection fraction ≤35% and underwent in-hospital revascularization (10,014 percutaneous coronary intervention (PCI) and 1,647 coronary artery bypass grafting (CABG)) were linked with Medicare claims to determine rates of 1-year ICD implantation. The association between ICD implantation and 2-year mortality was assessed. Of 11,661 included patients, an ICD was implanted in 1,234 (10.6%) within 1 year of revascularization (1,063 (10.6%) PCI and 171 (10.4%) CABG). Among PCI-treated patients, in-hospital ventricular arrhythmia (adjusted hazard ratio [aHR] 1.60, 95% confidence interval [CI] 1.34 to 1.92), 2-week cardiology follow-up (aHR 1.48, 95% CI 1.29 to 1.70), readmission for heart failure (aHR 3.21, 95% CI 2.73 to 3.79), and readmission for MI (aHR 2.18, 95% CI 1.66 to 2.85) were positively associated with ICD implantation. Among CABG-treated patients, in-hospital ventricular arrhythmia (aHR 2.33, 95% CI 1.39 to 3.91), and heart failure readmission (aHR 3.14, 95% CI 1.96 to 5.04) were positively associated with ICD implantation. Women were less likely to receive an ICD, regardless of the revascularization strategy. ICD implantation was associated with lower 2-year all-cause mortality (aHR 0.74, 95% CI 0.63 to 0.86). In conclusion, only 1 in 10 Medicare patients with low ejection fraction received an ICD within 1 year after revascularization. Contact with the healthcare system after discharge was associated with higher likelihood of ICD implantation. ICD implantation was associated with lower mortality following revascularization for MI.

Underuse of oral anticoagulants in privately insured patients with atrial fibrillation: A population being targeted by the IMplementation of a randomized controlled trial to imProve treatment with oral AntiCoagulanTs in patients with Atrial Fibrillation (IMPACT-AFib)

BACKGROUND

Many studies showing underuse of oral anticoagulants (OACs) in patients with atrial fibrillation (AF) predated the advent of the non-vitamin K antagonist OACs. We retrospectively examined use of OACs in a large commercially insured population.

METHODS

Administrative claims data from 4 research partners participating in FDA-Catalyst, a program of the Sentinel Initiative, were queried in September 2017. Patients were included if they were ≥30 years old with ≥365 days of medical/pharmacy coverage, and had ≥2 diagnosis codes for AF, a CHA₂DS₂-VASc score ≥2, absence of contraindications to OAC use, and no evidence of OAC use in the 365 days before the index AF diagnosis. The main outcome measures of the current analysis were rates of OAC use in the prior 12 months of cohort identification and factors associated with non-use.

RESULTS

A total of 197,806 AF patients met the eligibility criteria prior to assessment of OAC treatment. Of these, 179,580 (91%) patients were ≥65 years old and 73,286 (37%) patients were ≥80 years old. Half of the patients (98,903) were randomized to the early intervention arm in the IMPACT-AFib trial and constitute the cohort for this analysis. Of these, 32,295 (33%) had no evidence of OAC use in the prior 12 months. Compared with patients with evidence of OAC use in the prior 12 months, patients without OAC use were more likely to be ≥80 years old, women, and have a history of anemia (51% vs 47%) and less likely to have diabetes (41% vs 44%), history of stroke or TIA (15% vs 19%), and history of heart failure (39% vs 48%).

CONCLUSIONS

Despite a high risk of stroke, one-third of privately insured patients with AF and no obvious contraindications to an OAC were not treated with an OAC. There is an unmet need for evidence-based interventions that could lead to greater use of OACs in patients with AF at risk for stroke.

VVI pacing with normal QRS duration and ventricular function: MOST trial findings relevant to leadless pacemakers

BACKGROUND

Leadless pacemakers (LPs) provide ventricular pacing without the risks associated with transvenous leads and device pockets. LPs are appealing for patients who need pacing, but do not need defibrillator or cardiac resynchronization therapy. Most implanted LPs provide right ventricular pacing without atrioventricular synchrony (VVIR mode). The Mode Selection Trial in Sinus Node Dysfunction (MOST) showed similar outcomes in patients randomized to dual-chamber (DDDR) versus ventricular pacing (VVIR). We compared outcomes by pacing mode in LP-eligible patients from MOST.

METHODS

Patients enrolled in the MOST study with an left ventricular ejection fraction (LVEF) >35%, QRS duration (QRSd) <120 ms and no history of ventricular arrhythmias or prior implantable cardioverter defibrillators were included (LP-eligible population). Cox proportional hazards models were used to test the association between pacing mode and death, stroke or heart failure (HF) hospitalization and atrial fibrillation (AF).

RESULTS

Of the 2010 patients enrolled in MOST, 1284 patients (64%) met inclusion criteria. Baseline characteristics were well balanced across included patients randomized to DDDR (N = 630) and VVIR (N = 654). Over 4 years of follow-up, there was no association between pacing mode and death, stroke or HF hospitalization (VVIR HR 1.28 [0.92-1.75]). VVIR pacing was associated with higher risk of AF (HR 1.32 [1.08-1.61], P = .007), particularly in patients with no history of AF (HR 2.38 [1.52-3.85], P < .001).

CONCLUSION

In patients without reduced LVEF or prolonged QRSd who would be eligible for LP, DDDR, and VVIR pacing demonstrated similar rates of death, stroke or HF hospitalization; however, VVIR pacing significantly increased the risk of AF development.

Disparities in the Management of Newly Diagnosed Paroxysmal Supraventricular Tachycardia for Women Versus Men in the United States

Background Information on differences in paroxysmal supraventricular tachycardia (PSVT) diagnosis, healthcare resource use, expenditures, and treatment among women versus men is limited. Methods and Results Study participants identified in the IBM MarketScan Commercial Research Databases were aged 18 to 40 years with newly diagnosed PSVT (International Classification of Diseases, Ninth Revision [ICD-9]: 427.0; International Classification of Diseases, Tenth Revision [ICD-10]: I47.1) from October 1, 2012, through September 30, 2016, observable 1 year preindex and postindex diagnosis. Study outcomes were mean annual per-patient healthcare resource use and expenditures before and after diagnosis. Among 5466 patients newly diagnosed with PSVT, most (66.9%) were women. Compared with men, women with PSVT tended to have higher rates of anxiety (13.9% versus 10.9%; P<0.01) and chronic pulmonary disease (10.9% versus 8.3%; P<0.01). Following diagnosis, mean annual per-patient expenditures increased for all patients, but were significantly lower for women ($26 922 versus $33 112; P<0.05), reflecting lower spending for services billed as a result of a PSVT diagnosis ($8471 versus $11 405; P<0.05). After diagnosis, nearly half of all patients had at least 1 emergency department visit (women versus men, 49.6% versus 44.5%; P<0.01) and more had hospital admissions (women versus men, 24.7% versus 20.0%; P<0.01). Fewer women were treated with cardiac ablation (12.6% versus 15.3%; P<0.01), and more were treated with medical therapy, including β blockers or calcium channel blockers (odds ratio, 1.15; 95% CI, 1.02-1.31). Conclusions Among patients aged 18 to 40 years, ≈2 of 3 patients diagnosed with PSVT were women. After diagnosis, spending was significantly lower for women, reflecting lower ablation rates and less spending on services with a PSVT diagnosis.

Bystander Ethics and Good Samaritanism: A Paradox for Learning Health Organizations

In 2012, a U.S. Institute of Medicine report called for a different approach to health care: "Left unchanged, health care will continue to underperform; cause unnecessary harm; and strain national, state, and family budgets." The answer, they suggested, would be a "continuously learning" health system. Ethicists and researchers urged the creation of "learning health organizations" that would integrate knowledge from patient-care data to continuously improve the quality of care. Our experience with an ongoing research study on atrial fibrillation-a trial known as IMPACT-AFib-gave us some insight into one of the challenges that will have to be dealt with in creating these organizations. Although the proposed educational intervention study placed no restrictions on what providers and health plans could do, the oversight team argued that the ethical principle of beneficence did not allow the researchers to be "bystanders" in relation to a control group receiving suboptimal care. In response, the researchers designed a "workaround" that allowed the project to go forward. We believe the experience suggests that what we call "bystander ethics" will create challenges for the kinds of quality improvement research that LHOs are designed to do.

Cardiac Implantable Electronic Devices: A Window Into the Evolution of Conduction Disease in Cardiac Amyloidosis

OBJECTIVES

This study characterized the relationship between conduction disease and cardiac amyloidosis (CA) through longitudinal analysis of cardiac implantable electronic device (CIED) data.

BACKGROUND

Bradyarrhythmias and tachyarrhythmias are commonly reported in CA and may precede a CA diagnosis, although the natural history of conduction disease in CA is not well-described.

METHODS

Patients with CA (transthyretin amyloidosis cardiomyopathy [ATTR-CM] and light-chain amyloidosis [AL-CA]) and a CIED were identified within the Duke University Health System. Patient characteristics at the time of implantation, including demographics and data relevant to CA diagnosis, cardiac imaging, and CIED were recorded. CIED interrogations were analyzed for pacing and atrial fibrillation (AF) burden, activity level, lead parameters, and ventricular arrhythmia incidence and/or therapy.

RESULTS

Thirty-four patients with CA (7 with AL-CA, 27 with ATTR-CM [78% with wild-type]; 82% men) with median age of 75 years and a mean ejection fraction of 42 ± 13% had a CIED implanted for bradycardia (65%) or prevention of sudden cardiac death (35%). CIED implantation preceded CA diagnosis in 14 patients (41%). Over a mean follow-up of 3.1 ± 4.0 years, right ventricular sensing amplitudes decreased but did not result in device malfunction; lead impedances and capture thresholds remained stable. Between post-implantation years 1 and 5, mean ventricular pacing increased from 56 ± 9% to 96 ± 1% (p = 0.003) and AF burden increased from 2 ± 1.3 to 17 ± 3 h/day (p = 0.0002). Ventricular arrhythmias were common (mean episodes per patient per year: 6.7 ± 2.3 [ATTR-CM] and 5.1 ± 3.2 [AL-CA]) but predominately nonsustained; only 1 patient with AL-CA required implantable cardioverter-defibrillator therapy.

CONCLUSIONS

Longitudinal analysis of CIED data in patients with CA revealed progressive conduction disease, with high AF burden and eventual dependence on ventricular pacing, although lead parameters remained stable. Ventricular arrhythmias were common but predominantly nonsustained, particularly in ATTR-CM.

Catheter ablation of atrial fibrillation in cardiac amyloidosis

BACKGROUND

Cardiac amyloidosis is a progressive infiltrative disease involving deposition of amyloid fibrils in the myocardium and cardiac conduction system that frequently manifests with heart failure (HF) and arrhythmias, most frequently atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT).

METHODS

We performed an observational retrospective study of patients with a diagnosis of cardiac amyloid who underwent catheter ablation at our institution between January 1, 2011 and December 1, 2018. Patient demographics, procedural characteristics, and outcomes were determined by manual chart review.

RESULTS

A total of 13 catheter ablations were performed over the study period in patients with cardiac amyloidosis, including 10 AT/AF/AFL ablations and three atrioventricular nodal ablations. Left ventricular ejection fraction was lower at the time of AV node ablation than catheter ablation of AT/AF/AFL (23% vs 40%, P = .003). Cardiac amyloid was diagnosed based on the results of preablation cardiac MRI results in the majority of patients (n = 7, 70%). The HV interval was prolonged at 60 ± 15 ms and did not differ significantly between AV nodal ablation patients and AT/AF/AFL ablation patients (69 ± 18 ms vs 57 ± 14 ms, P = .36). The majority of patients undergoing AT/AF/AFL ablation had persistent AF (n = 7, 70%) and NYHA class II (n = 5, 50%) or III (n = 5, 50%) HF symptoms, whereas patients undergoing AV node ablation were more likely to have class IV HF (n = 2, 66%, P = .014). Arrhythmia-free survival in CA patients after catheter ablation of AT/AF/AFL was 40% at 1 year and 20% at 2 years.

CONCLUSIONS

Catheter ablation of AT/AF/AFL may be a feasible strategy for appropriately selected patients with early to mid-stage CA, whereas AV node ablation may be more appropriate in patients with advanced-stage CA.

Collaborative care for the wearable cardioverter defibrillator patient: Getting the patient and medical team "vested and active"

Patients with a reduced ejection fraction of 35% or less and a history of myocardial infarction (MI) are at increased risk of sudden cardiac death (SCD). These patients have a class I indication for an implantable cardioverter-defibrillator after allowing time for medical therapy optimization and potential cardiac recovery. The rates of SCD are highest in this "gap" period early after a cardiac event, and the wearable cardioverter-defibrillator (WCD) is an intervention that can be used to protect against SCD during this time period. There has been a clinical trial that randomized patients with a reduced ejection fraction at the time of MI to a WCD versus control. Results of the trial showed no statistically significant difference in the primary endpoint of SCD. There are many intricacies to the interpretation of the trial, including the importance of patient adherence to WCD therapy, which is affected by the patient experience and psychological factors. Patients with a new cardiomyopathy are affected by a mix of psychological factors, including the feeling of safety and protection from a WCD contrasted by the WCD providing a reminder of awareness and fear of ventricular arrhythmias and SCD. Beyond the capabilities of a WCD to defibrillate a life-threatening ventricular arrhythmia, the device can also provide activity and heart failure diagnostics monitoring. Patients need to be engaged in shared decision-making conversations about a WCD, so that patients can make a decision based on their own values construct, ultimately increasing adherence among the patients that want a WCD.

Catheter ablation of atrial fibrillation in patients with diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). Few studies have compared clinical outcomes after catheter ablation between patients with and those without DM.

OBJECTIVE

The purpose of this study was to compare AF ablation outcomes in patients with and those without DM.

METHODS

We performed a retrospective analysis of 351 consecutive patients who underwent first-time AF ablation. Clinical outcomes included freedom from recurrent atrial arrhythmia, symptom burden (Mayo AF Symptom Inventory score), cardiovascular and all-cause hospitalizations, and periprocedural complications.

RESULTS

Patients with DM (n = 65) were older, had a higher body mass index, more persistent AF, more hypertension, and larger left atrial diameter (P <.05 for all). Median (Q1, Q3) total radiofrequency duration [64.0 (43.6, 81.4) minutes vs 54.3 (39.2, 76.4) minutes; P = .132] and periprocedural complications (P = .868) did not differ between patients with and those without DM. After a median follow-up of 29.5 months, arrhythmia recurrence was significantly higher in the DM group compared to the no-DM group after adjustment for baseline differences (adjusted hazard ratio [HR] 2.24; 95% confidence [CI] 1.42-3.55; P = .001). There was a nonsignificant trend toward higher AF recurrence with worse glycemic levels (HR 1.29; 95% CI 0.99-1.69; P = .064).

CONCLUSION

Although safety outcomes associated with AF ablation were similar between patients with and those without DM, arrhythmia-free survival was significantly lower among patients with DM. Poor glycemic control seems to an important risk factor for AF recurrence.

Patterns of oral anticoagulation use with cardioversion in clinical practice

BACKGROUND

Cardioversion is common among patients with atrial fibrillation (AF). We hypothesised that novel oral anticoagulants (NOAC) used in clinical practice resulted in similar rates of stroke compared with vitamin K antagonists (VKA) for cardioversion.

METHODS

Using the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II, patients with AF who had a cardioversion, follow-up data and an AF diagnosis within 6 months of enrolment were identified retrospectively. Clinical outcomes were compared for patients receiving a NOAC or VKA for 1 year following cardioversion.

RESULTS

Among 13 004 patients with AF, 2260 (17%) underwent cardioversion. 1613 met the inclusion criteria for this analysis. At the time of cardioversion, 283 (17.5%) were receiving a VKA and 1330 (82.5%) a NOAC. A transoesophageal echocardiogram (TOE) was performed in 403 (25%) cardioversions. The incidence of stroke/transient ischaemic attack (TIA) at 30 days was the same for patients having (3.04 per 100 patient-years) or not having (3.04 per 100 patient-years) a TOE (p=0.99). There were no differences in the incidence of death (HR 1.19, 95% CI 0.62 to 2.28, p=0.61), cardiovascular hospitalisation (HR 1.02, 95% CI 0.76 to 1.35, p=0.91), stroke/TIA (HR 1.18, 95% CI 0.30 to 4.74, p=0.81) or bleeding-related hospitalisation (HR 1.29, 95% CI 0.66 to 2.52, p=0.45) at 1 year for patients treated with either a NOAC or VKA.

CONCLUSIONS

Cardioversion was a low-risk procedure for patients treated with NOAC, and there were statistically similar rates of stroke/TIA 30 days after cardioversion as for patients treated with VKA. There were no statically significant differences in death, stroke/TIA or major bleeding at 1 year among patients treated with NOAC compared with VKA after cardioversion.

Practical challenges in the conduct of pragmatic trials embedded in health plans: Lessons of IMPACT-AFib, an FDA-Catalyst trial

IMPACT-AFib was an 80,000-patient randomized clinical trial implemented by five US insurance companies (health plans) aimed at increasing the use of oral anticoagulants by individuals with atrial fibrillation who were at high risk of stroke and not on treatment. The underlying thesis was that patients could be change agents to initiate prescribing discussions with their providers. We tested the effect of mailing information to both patients and their providers. We used administrative medical claims and pharmacy dispensing data to identify eligible patients, to randomize them to an early or delayed intervention, and to assess clinical outcomes. The core data were analysis-ready datasets each site had created and curated for the FDA's Sentinel System, supplemented by updated "fresh" pharmacy and enrollment data to ensure eligibility at the time of intervention. Following mutually agreed upon procedures, sites linked to additional internal source data to implement the intervention-educational information mailed to patients and their providers in the early intervention arm, and to providers of patients in the delayed intervention arm approximately 12 months later. The primary analysis compares the early intervention arm to the delayed intervention arm, prior to the delayed intervention being conducted (i.e. compares intervention to non-intervention). The endpoints of interest were evidence of initiation of anticoagulation (primary) as well as clinical endpoints, including stroke and hospitalization for bleeding. Major challenges, some unanticipated, identified during the planning phase include convening multi-stakeholder investigator teams and advisors, addressing ethical concerns about not intervening in a usual care comparison group, and identifying and avoiding interference with sites' routine programs that were similar to the intervention. Needs and challenges during the implementation phase included the fact that even limited site-specific programming greatly increased time and effort, the need to refresh research data extracts immediately before outreach to patients and providers, potential difficulty identifying low-cost medications such as warfarin that may not be reimbursed by health plans and so not discoverable in dispensing data, the need to develop workarounds when "providers" in claims data were facilities, difficulty addressing clustering of patients by provider because providers can have multiple identifiers within and between health plans, and the need to anticipate loss to follow up because of health plan disenrollment or change in benefits. As pragmatic trials begin to shape evidence generation within clinical practice, investigators should anticipate issues inherent to claims data and working with multiple large sites. In IMPACT-AFib, we found that investing in collaboration and communication among all parties throughout all phases of the study helped ensure common understanding, early identification of challenges, and streamlined actual implementation.

Lead Extraction for Cardiovascular Implantable Electronic Device Infection in Patients With Left Ventricular Assist Devices

OBJECTIVES

The goal of this study was to assess the utility of transvenous lead extraction for cardiovascular implantable electronic device (CIED) infection in patients with a left ventricular assist device (LVAD).

BACKGROUND

The use of transvenous lead extraction for the management CIED infection in patients with a durable LVAD has not been well described.

METHODS

Clinical and outcomes data were collected retrospectively among patients who underwent lead extraction for CIED infection after LVAD implantation at Duke University Hospital.

RESULTS

Overall, 27 patients (n = 6 HVAD; n = 15 HeartMate II; n = 6 Heartmate III) underwent lead extraction for infection. Median (interquartile range) time from LVAD implantation to infection was 6.1 (2.5 to 14.9) months. Indications included endocarditis (n = 16), bacteremia (n = 9), and pocket infection (n = 2). Common pathogens were Staphylococcus aureus (n = 10), coagulase-negative staphylococci (n = 7), and Enterococcus faecalis (n = 3). Sixty-eight leads were removed, with a median lead implant time of 5.7 (3.6 to 9.2) years. Laser sheaths were used in all procedures, with a median laser time of 35.0 s (17.5 to 85.5s). Mechanical cutting tools were required in 11 (40.7%) and femoral snaring in 4 (14.8%). Complete procedural success was achieved in 25 (93.6%) patients and clinical success in 27 (100%). No procedural failures or major adverse events occurred. Twenty-one patients (77.8%) were alive without persistent endovascular infection 1 year after lead extraction. Most were treated with oral suppressive antibiotics after extraction (n = 23 [82.5%]). Persistent infection after extraction occurred in 4 patients and was associated with 50% 1-year mortality.

CONCLUSIONS

Transvenous lead extraction for LVAD-associated CIED infection can be performed safely with low rates of persistent infection and 1-year mortality.

Apixaban Versus Warfarin in Patients With Atrial Fibrillation and Advanced Chronic Kidney Disease

Background:

Compared with the general population, patients with advanced chronic kidney disease have a >10-fold higher burden of atrial fibrillation. Limited data are available guiding the use of nonvitamin K antagonist oral anticoagulants in this population.

Methods:

We compared the safety of apixaban with warfarin in 269 patients with atrial fibrillation and advanced chronic kidney disease (defined as creatinine clearance [CrCl] 25 to 30 mL/min) enrolled in the ARISTOTLE trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation). Cox proportional models were used to estimate hazard ratios for major bleeding and major or clinically relevant nonmajor bleeding. We characterized the pharmacokinetic profile of apixaban by assessing differences in exposure using nonlinear mixed effects models.

Results:

Among patients with CrCl 25 to 30 mL/min, apixaban caused less major bleeding (hazard ratio, 0.34 [95% CI, 0.14–0.80]) and major or clinically relevant nonmajor bleeding (hazard ratio, 0.35 [95% CI, 0.17–0.72]) compared with warfarin. Patients with CrCl 25 to 30 mL/min randomized to apixaban demonstrated a trend toward lower rates of major bleeding when compared with those with CrCl >30 mL/min ( P interaction=0.08) and major or clinically relevant nonmajor bleeding ( P interaction=0.05). Median daily steady-state areas under the curve for apixaban 5 mg twice daily were 5512 ng/(mL·h) and 3406 ng/(mL·h) for patients with CrCl 25 to 30 mL/min or >30 mL/min, respectively. For apixaban 2.5 mg twice daily, the median exposure was 2780 ng/(mL·h) for patients with CrCl 25 to 30 mL/min. The area under the curve values for patients with CrCl 25 to 30 mL/min fell within the ranges demonstrated for patients with CrCl >30 mL/min.

Conclusions:

Among patients with atrial fibrillation and CrCl 25 to 30 mL/min, apixaban caused less bleeding than warfarin, with even greater reductions in bleeding than in patients with CrCl >30 mL/min. We observed substantial overlap in the range of exposure to apixaban 5 mg twice daily for patients with or without advanced chronic kidney disease, supporting conventional dosing in patients with CrCl 25 to 30 mL/min. Randomized, controlled studies evaluating the safety and efficacy of apixaban are urgently needed in patients with advanced chronic kidney disease, including those receiving dialysis.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00412984.

Implantable cardioverter-defibrillator lead revision following left ventricular assist device implantation

INTRODUCTION

Lead dysfunction can lead to serious consequences including failure to treat ventricular tachycardia or fibrillation (VT/VF). The incidence and mechanisms of lead dysfunction following left ventricular assist device (LVAD) implantation are not well-described. We sought to determine the incidence, mechanisms, timing, and complications of right ventricular lead dysfunction requiring revision following LVAD implantation.

METHODS

Retrospective observational chart review of all LVAD recipients with pre-existing implantable cardioverter-defibrillator (ICD) from 2009 to 2018 was performed including device interrogation reports, laboratory and imaging data, procedural reports, and clinical outcomes.

RESULTS

Among 583 patients with an ICD in situ undergoing LVAD implant, the median (interquartile range) age was 62.5 (15.7) years, 21% were female, and the types of LVADs included HeartWare HVAD (26%), HeartMate II (52%), and HeartMate III (22%). Right ventricular lead revision was performed in 38 patients (6.5%) at a median (25th, 75th) of 16.4 (3.6, 29.2) months following LVAD. Mechanisms of lead dysfunction included macrodislodgement (n = 4), surgical lead injury (n = 4), recall (n = 3), insulation failure (n = 8) or conductor fracture (n = 7), and alterations in the lead-myocardial interface (n = 12). Undersensing requiring revision occurred in 22 (58%) cases. Clinical sequelae of undersensing included failure to detect VT/VF (n = 4) and pacing-induced torsade de pointes (n = 1). Oversensing occurred in 12 (32%) and sequelae included inappropriate antitachycardia pacing ([ATP], n = 8), inappropriate ICD shock (n = 6), and ATP-induced VT (n = 1).

CONCLUSION

The incidence of right ventricular lead dysfunction following LVAD implantation is significant and has important clinical sequelae. Physicians should remain vigilant for lead dysfunction after LVAD surgery and test lead function before discharge.

Outcomes following cardioversion for patients with cardiac amyloidosis and atrial fibrillation or atrial flutter

Atrial arrhythmias commonly occur in patients with cardiac amyloidosis (CA), but there is limited data on safety or efficacy of cardioversion (DCCV) for management of these rhythms in CA. We identified 25 patients with CA (20 with transthyretin (TTR) and 5 with light-chain (AL) amyloidosis) at Duke University who underwent DCCV for atrial arrhythmias and documented procedural success, complications, and long-term morbidity and mortality. While DCCV successfully restored sinus rhythm in 96% of patients, 36% of patients experienced immediate procedural complications (primarily bradycardia and hypotension), 80% had recurrence of atrial arrhythmias at 1 year, and 52% died at 3 years, highlighting short-term safety concerns, long-term inefficacy, and poor prognosis associated with symptomatic atrial arrhythmias requiring DCCV in CA.