BACKGROUND/RATIONALE:
AF is common in patients with permanent pacemakers (PPM) and implantable cardioverter-defibrillators (ICD). Using these devices, atrial arrhythmias can be identified in real-time and documented through auto-triggered alerts that are recorded in the device memory. Unlike any other health care system in the world, the VA has a national infrastructure to centralize remote monitoring of all implantable cardiac devices. The VA National Cardiac Device Surveillance Center (NCDSC), which monitors all cardiac devices implanted or followed in the VA, tracks over 32,000 pacemakers and defibrillators from over 125 participating VA centers. As part of the workflow of NCDSC, VA providers receive real-time notification when atrial arrhythmias have been detected, so that patients may receive appropriate stroke prevention therapy. The rationale is to inform providers of atrial arrhythmias that would necessitate stroke prevention therapy. However, the impact of these notifications on initiating antithrombotic therapy or preventing stroke is not yet known. We will investigate whether atrial arrhythmia notifications (AAN) improve stroke prophylaxis prescription rates and clinical outcomes.

OBJECTIVE(S):
Our study objectives are:
1) to characterize the association of atrial arrhythmia alerts for prescription of anticoagulation.
2) to determine site-level characteristics associated with anticoagulation prescription (and non-prescription) for eligible patients (moderate to high risk of stroke and low risk of bleeding) after alert transmission for device-detected AT/AF.
3) To determine differences in stroke and mortality associated with anticoagulation initiation vs. non-initiation after atrial arrhythmia alerts.

METHODS:
To achieve the stated objectives of this study, we will merge data from NCDSC, VA and Medicare. Using NCDSC data, we will identify all Veterans receiving pacemaker or defibrillator surveillance between FY2004 and FY2012. Our experienced research team will merge this with Administrative VA and Medicare data for all Veterans with atrial fibrillation (AF) or heart failure. The analysis cohort will include Veterans that received at least one atrial arrhythmia notification for newly detected atrial tachycardia or atrial fibrillation (AT/AF) during the observation period. For Aim 1, we will determine the proportion of patients that received anticoagulation in the 60 days following the atrial arrhythmia notification, stratified by duration AF episode, 30-day AF burden, CHADS2 score, ATRIA bleeding risk score, and other covariates. For Aim 2, we will also aggregate data by enrollment center to evaluate site-level variation and identify which site-level factors explain the variation in post-notification anticoagulation prescription in appropriate patients. Finally, for Aim 3, we will use post-notification anticoagulation prescription as the primary predictor variable and stroke/TIA as the primary outcome using validated high sensitivity and high-specificity stroke algorithms across VA and Medicare inpatient claims.

FINDINGS/RESULTS:
We have integrated one large data feed of 10,000 patients with implantable devices with remote monitoring into the VA system.

The first study evaluated the number of patients with AF/AT episodes (mode switch) and identified the temporal association to stroke.

We identified 9,850 patients with CIEDs remotely monitored in the Veterans Administration Health Care System between 2002-2012. There were 187 patients with acute ischemic stroke and continuous heart rhythm monitoring for 120 days pre-stroke (age 69 8.4 years).

Among these 187 paitents, only 23% had any AT/AF in the 30 day prior to stroke, which dramatically challenges the fundamental assumptions and conceptual framework of the AF-stroke relationship. To further evaluate the association of temporal changes in AF to stroke outcomes, we compared each patient's daily AF burden in the 30 days pre-stroke ("case" period) to days 91-120 pre-stroke ("control" period). Defining positive AF burden as 5.5 hours of AF on any given day, 156 patients (83%) had no positive AF burden in both periods and had little to no AF; 15 (8%) patients had positive AF burden in both periods. Among the discordant "informative" patients, 13 exceeded 5.5 hours of AF in the case but not control period, while 3 had positive AF burden in the control but not case period (warfarin-adjusted odds ratio for stroke of 4.2 (95% CI: 1.513.4). The odds ratio for stroke was highest (17.4; 95% CI: 5.39-73.1) in the five days immediately following a qualifying occurrence of AF and decreased towards one as the period following the AF occurrence increased beyond 30 days.


While these epidemiological and risk prediction findings are not tied to the health services aims, the findings to help to inform the overall analytic strategy. Our next step is evaluating anticoagulation starts and stops and superimposing that time-series data with the remote monitoring data to then look at effectiveness of anticoagualtion in this setting.

Next, we will then cluster these data based on VA site to examine site level variation in response to AT/AF alerts, anticoagulation prescripton, and comparison in outcomes.





IMPACT:
This study will make multiple meaningful contributions to VA's effects to improve stroke prevention for its patients, at both clinical and policy levels. Our project is co-sponsored by two of the VA Quality Enhancement Research Initiative (QUERI) centers: Stroke QUERI and Chronic Heart Failure (CHF) QUERI. The QUERI mission is "to enhance the quality and outcomes of VA health care by systematically implementing clinical research and evidence-based recommendations into routine clinical practice". This project will correlate the efficiency and effectiveness of automated arrhythmia notification response with local patient care structure. If the project identifies facilities where the alerts are not leading to referral for anticoagulation services, then future projects, in partnership with NCDSC and the National Program in Cardiology, can examine barriers and facilitators to using the notifications to trigger consideration for stroke prophylaxis prescription and refine the implementation strategy in the VA. The overarching goal is to decrease stroke morbidity, health care utilization, and costs by optimizing existing care infrastructure. The project is expected to finish on time.

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External Links for this Project

NIH Reporter

Grant Number: I21HX001181-01A1
Link: https://reporter.nih.gov/project-details/8660204

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PUBLICATIONS:

Journal Articles

1. Chang AY, Kaiser D, Ullal AJ, Perino AL, Heidenreich PA, Turakhia M. Evaluating the Cost-Effectiveness of Catheter Ablation in Atrial Fibrillation. Arrhythmia & electrophysiology review. 2014 Nov 22; 3(3):177-183. [view]
2. Chyou JY, Hunter TD, Mollenkopf SA, Turakhia MP, Reynolds MR. Individual and Combined Risk Factors for Incident Atrial Fibrillation and Incident Stroke: An Analysis of 3 Million At-Risk US Patients. Journal of the American Heart Association. 2015 Jul 23; 4(7). [view]
3. Prasad M, Flowers E, Divakaruni M, Molina C, Mathur A, Assimes TL, Aouizerat BE, Sathe A, Malhotra D, Turakhia M. The relationship of lipoprotein(a), C-reactive protein and homocysteine with metabolic syndrome in South Asians. Journal of Indian College of Cardiology. 2014 Dec 1; 4(4):208-213. [view]

Conference Presentations

1. Han L, Scmitt S, Ziegler PD, Altman RB, Fan J, Than CT, Turakhia M. Can Big Data Approaches Predict Impending Stroke From Continuous Atrial Fibrillation Data? Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 14; Boston, MA. [view]
2. Turakhia M. Career and Research Opportunities in the VA Health Care System. Presented at: American Heart Association Scientific Sessions and Resuscitation Annual Science Symposium; 2014 Nov 15; Chicago, IL. [view]
3. Narayan SM, Zaman J, Krummen DE, Turakhia M, Schricker AA, Baykaner T, Wang P, Rappel WJ. Continuous Mapping Can Define Mechanisms For the Termination or Slowing of Human Atrial Fibrillation by Ablation. Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 15; Boston, MA. [view]
4. Perino AC, Fan J, Chang AY, Kaiser D, Heidenreich PA, Swan C, Nayaran SM, Wang PJ, Turakhia M. Cost Variation and Associated Outcomes of Catheter Ablation for Atrial Fibrillation. Presented at: American College of Cardiology Annual Charter Meeting; 2015 Mar 14; San Diego, CA. [view]
5. Hunter TD, Lip GL, Quiroz ME, Mollenkopf SA, Turakhia M. Cryptogenic Strokes and Recurrence Rates in Relation to the CHADS2 and CHA2DS2-VASc Risk Scores. Poster session presented at: American Heart Association / American Stroke Association International Stroke Conference; 2015 Feb 11; Nashville, TN. [view]
6. Swan CH, Fan J, Schmitt S, Than CT, Ullal AJ, Heidenreich PA, Turakhia M. Decreased mortality associated with cardiology specialty management of newly diagnosed atrial fibrillation: Findings from the TREAT-AF study. Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 13; Boston, MA. [view]
7. Than CT, Frayne SM, Phibbs CS, Heidenreich PA, Schmitt S, Xu X, Ullal A, Turakhia M. Dual Health System Use in Veterans: Impact on Quality and Outcomes of Warfarin Management in Atrial Fibrillation. Presented at: Agency for Healthcare Research and Quality National Research Service Award Trainees Research Conference; 2015 Jun 13; Minneapolis, MN. [view]
8. Turakhia M, Shafrin J, Bognar K, Goldman DP, Mendys PM, Abdulsattar Y, Wiederkehr D, Trocio J. Economic burden of undiagnosed nonvalvular atrial fibrillation in the United States. Poster session presented at: American College of Cardiology Annual Scientific Session; 2015 Mar 16; San Diego, CA. [view]
9. Nazarian S, Reynolds MR, Ryan MP, Hunter TD, Wolff SD, Mollenkopf SA, Turakhia M. Estimating the Likelihood of MRI In Patients after ICD Implantation: A 10-Year Prediction Model. Poster session presented at: American College of Cardiology Annual Scientific Session; 2015 Mar 14; San Diego, CA. [view]
10. Kaiser D, Tsai V, Heidenreich PA, Goldstein MK, Wang Y, Curtis J, Turakhia M. ICD Implantations for Primary Prevention in the United States: Inappropriate Care or Inadequate Documentation? Insights from the NCDR ICD Registry. Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 14; Boston, MA. [view]
11. Than CT, Schmitt S, Heidenreich PA, Ullal A, Frayne SM, Phibbs CS, Turakhia M. Impact of Treating Specialty on Treatment Strategy for New Atrial Fibrillation: Findings from the VA TREAT-AF Study. Poster session presented at: Agency for Healthcare Research and Quality National Research Service Award Trainees Research Conference; 2015 Jun 13; Minneapolis, MN. [view]
12. Gold MR, Saba S, Atwater BD, Sloman LS, Bharmi R, Nabutovsky Y, Turakhia M. Incremental survival benefit of high percent biventricular pacing in quadripolar CRT. Presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 14; Boston, MA. [view]
13. Turakhia M. Intention-to-Tweet: A Randomized Trial of Social Media from Circulation. Presented at: American Heart Association Scientific Sessions and Resuscitation Annual Science Symposium; 2014 Nov 18; Chicago, IL. [view]
14. Turakhia M. My patient has AF. Should I implant a biventricular device? Presented at: American Heart Association Scientific Sessions and Resuscitation Annual Science Symposium; 2014 Nov 16; Chicago, IL. [view]
15. Kaiser D, Fan J, Schmitt S, Piccini JP, Than CT, Ullal AJ, Heidenreich PA, Turakhia M. Paradoxical Sex Differences in Clinical Outcomes after Catheter Ablation of Atrial Fibrillation. Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 16; Boston, MA. [view]
16. Singer D, Ziegler PC, Schmitt SS, Chang Y, Fan J, Than CT, Turakhia M. Paroxysmal Atrial Fibrillation Poses a Large but Transient Increase in Ischemic Stroke Risk: A Case-Crossover Study. Poster session presented at: American College of Cardiology Annual Scientific Session; 2015 Mar 14; San Diego, CA. [view]
17. Turakhia M. Preventing Stroke in Atrial Fibrillation. Presented at: Get in Rhythm Stay in Rhythm Atrial Fibrillation Patient Conference; 2015 Mar 28; Dallas, TX. [view]
18. Gold MR, Sloman LS, Karst E, Nabutovsky Y, Turakhia M. Quadripolar leads provide greater survival benefit in patients enrolled in remote monitoring. Presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 15; Boston, MA. [view]
19. Turakhia M, Atwater BD, Saba S, Sloman LS, Nabutovsky Y, Dalal N, Gold MR. Quadripolar LV leads are associated with decreased shock burden in CRT-D patients. Presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 14; Boston, MA. [view]
20. Turakhia M, Forleo GB, Prillinger J, Kumar C, Nabutovsky Y, Gold M. Quadripolar LV Leads are Associated with Fewer Replacements and Deactivations than Bipolar LV Leads in CRT-P. Presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 15; Boston, MA. [view]
21. Turakhia M, Forleo GB, Prillinger J, Kumar C, Nabutovsky Y, Gold MR. Quadripolar LV leads are associated with fewer replacements and deactivations than bipolar LV leads in CRT-P. Presented at: European Society of Cardiology / European Heart Rhythm Association EUROPACE-CARDIOSTIM Congress; 2015 Jun 23; Milan, Italy. [view]
22. Turakhia M. Quadripolar LV Leads: Interesting or Must-Have Technology. Presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 15; Boston, MA. [view]
23. Perino A, Fan J, Chang AY, Kaiser D, Heidenreich PA, Swan C, Narayan SN, Wang PJ, Turakhia M. Secular Trends of Effectiveness and Safety of Catheter Ablation for Atrial Fibrillation. Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 15; Boston, MA. [view]
24. Borne R, Katz DF, Peterson P, Betz J, Al-Khatib SM, Varosy PD, Wang Y, Hsu JC, Hoffmayer K, Kipp R, Hansen C, Turakhia M, Curtis J, Masoudi FA. Survival After Implantation of a Secondary Prevention ICD: An Analysis From the NCDR ICD Registry. Poster session presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 14; Boston, MA. [view]
25. Turakhia M. The Business Case of Quality Improvement of Care of Atrial Fibrillation. Presented at: American Heart Association / American Stroke Association Get With the Guidelines Atrial Fibrillation Forum; 2014 Nov 5; San Francisco, CA. [view]
26. Turakhia M. Treating Atrial Fibrillation with Medications. Presented at: Get in Rhythm Stay in Rhythm Atrial Fibrillation Patient Conference; 2015 Mar 28; Dallas, TX. [view]
27. Piccini JP, Sanders P, Shah R, Roberts G, Karst E, Turakhia M. Use of higher detection rates and delayed detection is associated with decreased shocks and improved survival in clinical practice. Paper presented at: Heart Rhythm Society Annual Scientific Sessions; 2015 May 14; Boston, MA. [view]
28. Turakhia M. What is the Evidence For and Against Aspirin Monotherapy in Low Risk AF Patients? Presented at: American Heart Association Scientific Sessions and Resuscitation Annual Science Symposium; 2014 Nov 16; Chicago, IL. [view]

DRA: Cardiovascular Disease
DRE: Treatment - Observational
Keywords: none
MeSH Terms: none