[Skip to Content]
[Skip to Content Landing]

Association of Surgical Left Atrial Appendage Occlusion With Subsequent Stroke and Mortality Among Patients Undergoing Cardiac Surgery

Educational Objective
To learn the association of surgical left atrial appendage occlusion (LAAO) with subsequent risk of stroke and mortality.
1 Credit CME
Key Points

Question  Is surgical occlusion of the left atrial appendage (LAAO) during cardiac surgery associated with reduced risk of stroke or all-cause mortality?

Finding  In this retrospective cohort study of 75 782 patients undergoing cardiac surgery, concurrent surgical LAAO, compared with no surgical LAAO, was significantly associated with a lower risk of stroke (hazard ratio, 0.73) and mortality (hazard ratio, 0.71) among a propensity score–matched cohort of 8590 patients.

Meaning  Surgical LAAO in patients undergoing concurrent cardiac surgery was associated with reduced risk of subsequent stroke and all-cause mortality.

Abstract

Importance  Surgical occlusion of the left atrial appendage (LAAO) may be performed during concurrent cardiac surgery. However, few data exist on the association of LAAO with long-term risk of stroke, and some evidence suggests that this procedure may be associated with subsequent development of atrial fibrillation (AF).

Objective  To evaluate the association of surgical LAAO performed during cardiac surgery with risk of stroke, mortality, and development of subsequent AF.

Design, Setting, and Participants  Retrospective cohort study using a large US administrative database that contains data from adult patients (≥18 years) with private insurance or Medicare Advantage who underwent coronary artery bypass graft (CABG) or valve surgery between January 1, 2009, and March 30, 2017, with final follow-up on March 31, 2017. One-to-one propensity score matching was used to balance patients on 76 dimensions to compare those with vs without LAAO, stratified by history of prior AF at the time of surgery.

Exposures  Surgical LAAO vs no surgical LAAO during cardiac surgery.

Main Outcomes and Measures  The primary outcomes were stroke (ie, ischemic stroke or systemic embolism) and all-cause mortality. The secondary outcomes were postoperative AF (AF within 30 days after surgery among patients without prior AF) and long-term AF-related health utilization (event rates of outpatient visits and hospitalizations).

Results  Among 75 782 patients who underwent cardiac surgery (mean age, 66.0 [SD, 11.2] years; 2 2091 [29.2%] women, 25 721 [33.9%] with preexisting AF), 4374 (5.8%) underwent concurrent LAAO, and mean follow-up was 2.1 (SD, 1.9) years. In the 8590 propensity score–matched patients, LAAO was associated with a reduced risk of stroke (1.14 vs 1.59 events per 100 person-years; hazard ratio [HR], 0.73 [95% CI, 0.56-0.96]; P = .03) and mortality (3.01 vs 4.30 events per 100 person-years; HR, 0.71 [95% CI, 0.60-0.84]; P < .001). LAAO was associated with higher rates of AF-related outpatient visits (11.96 vs 10.26 events per person-year; absolute difference, 1.70 [95% CI, 1.60-1.80] events per person-year; rate ratio, 1.17 [95% CI, 1.10-1.24]; P < .001) and hospitalizations (0.36 vs 0.32 event per person-year; absolute difference, 0.04 [95% CI, 0.02-0.06] event per person-year; rate ratio, 1.13 [95% CI, 1.05-1.21]; P = .002). In patients with prior AF (6438/8590 [74.9%]) with vs without LAAO, risk of stroke was 1.11 vs 1.71 events per 100 person-years (HR, 0.68 [95% CI, 0.50-0.92]; P = .01) and risk of mortality was 3.22 vs 4.93 events per 100 person-years (HR, 0.67 [95% CI, 0.56-0.80]; P < .001), respectively. In patients without prior AF (2152/8590 [25.1%]) with vs without LAAO, risk of stroke was 1.23 vs 1.26 events per 100 person-years (HR, 0.95 [95% CI, 0.54-1.68]), risk of mortality was 2.30 vs 2.49 events per 100 person-years (HR, 0.92 [95% CI, 0.61-1.37]), and risk of postoperative AF was 27.7% vs 20.2% events per 100 person-years (HR, 1.46 [95% CI, 1.22-1.73]; P < .001). The interaction term between prior AF and LAAO was not significant (P = .29 for stroke and P = .16 for mortality).

Conclusions and Relevance  Among patients undergoing cardiac surgery, concurrent surgical LAAO, compared with no surgical LAAO, was associated with reduced risk of subsequent stroke and all-cause mortality. Further research, including from randomized clinical trials, is needed to more definitively determine the role of surgical LAAO.

Sign in to take quiz and track your certificates

Buy This Activity

JN Learning™ is the home for CME and MOC from the JAMA Network. Search by specialty or US state and earn AMA PRA Category 1 CME Credit™ from articles, audio, Clinical Challenges and more. Learn more about CME/MOC

Article Information

Corresponding Author: Xiaoxi Yao, PhD, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (yao.xiaoxi@mayo.edu).

Accepted for Publication: April 18, 2018.

Author Contributions: Dr Yao had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Yao, Holmes, Melduni, Johnsrud, Noseworthy.

Acquisition, analysis, or interpretation of data: Yao, Gersh, Melduni, Sangaralingham, Shah, Noseworthy.

Drafting of the manuscript: Yao, Sangaralingham, Noseworthy.

Critical revision of the manuscript for important intellectual content: Yao, Gersh, Holmes, Melduni, Johnsrud, Shah, Noseworthy.

Statistical analysis: Yao, Holmes.

Administrative, technical, or material support: Holmes, Sangaralingham, Shah, Noseworthy.

Supervision: Holmes, Melduni, Shah, Noseworthy.

Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.

Funding/Support: This study was funded by the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery. Dr Melduni is supported by National Institutes of Health grant K01 (HL 135288).

Role of the Funder/Sponsor: The funder/sponsor had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

References
1.
Fingar  K, Stocks  C, Weiss  A, Steiner  C. Most frequent operating room procedures performed in US hospitals, 2003–2012: Healthcare Cost and Utilization Project Statistical Brief 186. https://www.hcup-us.ahrq.gov/reports/statbriefs/sb186-Operating-Room-Procedures-United-States-2012.jsp. Published December 2014. Accessed April 19, 2018.
2.
Benjamin  EJ, Wolf  PA, D’Agostino  RB,  et al.  Impact of atrial fibrillation on the risk of death.  Circulation. 1998;98(10):946-952.PubMedGoogle ScholarCrossref
3.
Kannel  WB, Wolf  PA, Benjamin  EJ, Levy  D.  Prevalence, incidence, prognosis, and predisposing conditions for atrial fibrillation: population-based estimates.  Am J Cardiol. 1998;82(8A):2N-9N.PubMedGoogle ScholarCrossref
4.
Blackshear  JL, Odell  JA.  Appendage obliteration to reduce stroke in cardiac surgical patients with atrial fibrillation.  Ann Thorac Surg. 1996;61(2):755-759.PubMedGoogle ScholarCrossref
5.
Friedman  DJ, Piccini  JP, Wang  T,  et al.  Association between left atrial appendage occlusion and readmission for thromboembolism among patients with atrial fibrillation undergoing concomitant cardiac surgery.  JAMA. 2018;319(4):365-374.PubMedGoogle ScholarCrossref
6.
Melduni  RM, Schaff  HV, Lee  HC,  et al.  Impact of left atrial appendage closure during cardiac surgery on the occurrence of early postoperative atrial fibrillation, stroke, and mortality.  Circulation. 2017;135(4):366-378.PubMedGoogle ScholarCrossref
7.
Hoit  BD, Shao  Y, Tsai  LM, Patel  R, Gabel  M, Walsh  RA.  Altered left atrial compliance after atrial appendectomy: influence on left atrial and ventricular filling.  Circ Res. 1993;72(1):167-175.PubMedGoogle ScholarCrossref
8.
Hoit  BD, Walsh  RA.  Regional atrial distensibility.  Am J Physiol. 1992;262(5, pt 2):H1356-H1360.PubMedGoogle Scholar
9.
Davis  CA  III, Rembert  JC, Greenfield  JC  Jr.  Compliance of left atrium with and without left atrium appendage.  Am J Physiol. 1990;259(4, pt 2):H1006-H1008.PubMedGoogle Scholar
10.
Wallace  PJ, Shah  ND, Dennen  T, Bleicher  PA, Crown  WH.  Optum Labs: building a novel node in the learning health care system  [published correction appears in Health Aff (Millwood). 2014;33(9):1703].  Health Aff (Millwood). 2014;33(7):1187-1194.PubMedGoogle ScholarCrossref
12.
Hershman  DL, Tsui  J, Wright  JD, Coromilas  EJ, Tsai  WY, Neugut  AI.  Household net worth, racial disparities, and hormonal therapy adherence among women with early-stage breast cancer.  J Clin Oncol. 2015;33(9):1053-1059.PubMedGoogle ScholarCrossref
13.
Austin  PC.  Optimal caliper widths for propensity-score matching when estimating differences in means and differences in proportions in observational studies.  Pharm Stat. 2011;10(2):150-161.PubMedGoogle ScholarCrossref
14.
Austin  PC.  Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples.  Stat Med. 2009;28(25):3083-3107.PubMedGoogle ScholarCrossref
15.
Gayat  E, Resche-Rigon  M, Mary  JY, Porcher  R.  Propensity score applied to survival data analysis through proportional hazards models: a Monte Carlo study.  Pharm Stat. 2012;11(3):222-229.PubMedGoogle ScholarCrossref
16.
Fine  JP, Gray  RJ.  A proportional hazards model for the subdistribution of a competing risk.  J Am Stat Assoc. 1999;94(446):496-509.Google ScholarCrossref
17.
Grambsch  PM, Therneau  TM.  Proportional hazards tests and diagnostics based on weighted residuals.  Biometrika. 1994;81(3):515-526.Google ScholarCrossref
18.
Prasad  V, Jena  AB.  Prespecified falsification end points.  JAMA. 2013;309(3):241-242.PubMedGoogle ScholarCrossref
19.
Li  F, Morgan  KL, Zaslavsky  AM.  Balancing covariates via propensity score weighting  [published online November 13, 2017].  J Am Stat Assoc. doi:10.1080/01621459.2016.1260466Google Scholar
20.
Tsai  YC, Phan  K, Munkholm-Larsen  S, Tian  DH, La Meir  M, Yan  TD.  Surgical left atrial appendage occlusion during cardiac surgery for patients with atrial fibrillation: a meta-analysis.  Eur J Cardiothorac Surg. 2015;47(5):847-854.PubMedGoogle ScholarCrossref
21.
Wolf  PA, Abbott  RD, Kannel  WB.  Atrial fibrillation as an independent risk factor for stroke: the Framingham Study.  Stroke. 1991;22(8):983-988.PubMedGoogle ScholarCrossref
22.
O’Brien  EC, Kim  S, Hess  PL,  et al.  Effect of the 2014 atrial fibrillation guideline revisions on the proportion of patients recommended for oral anticoagulation.  JAMA Intern Med. 2015;175(5):848-850.PubMedGoogle ScholarCrossref
23.
Kirchhof  P, Benussi  S, Kotecha  D,  et al.  2016 ESC guidelines for the management of atrial fibrillation developed in collaboration with EACTS.  Europace. 2016;18(11):1609-1678.PubMedGoogle ScholarCrossref
24.
Yao  X, Abraham  NS, Alexander  GC,  et al.  Effect of adherence to oral anticoagulants on risk of stroke and major bleeding among patients with atrial fibrillation.  J Am Heart Assoc. 2016;5(2):e003074.PubMedGoogle ScholarCrossref
25.
O’Brien  EC, Holmes  DN, Ansell  JE,  et al.  Physician practices regarding contraindications to oral anticoagulation in atrial fibrillation.  Am Heart J. 2014;167(4):601-609.PubMedGoogle ScholarCrossref
26.
Piccini  JP, Sievert  H, Patel  MR.  Left atrial appendage occlusion: rationale, evidence, devices, and patient selection.  Eur Heart J. 2017;38(12):869-876.PubMedGoogle Scholar
27.
Greenberg  JW, Lancaster  TS, Schuessler  RB, Melby  SJ.  Postoperative atrial fibrillation following cardiac surgery.  Eur J Cardiothorac Surg. 2017;52(4):665-672.PubMedGoogle ScholarCrossref
28.
Park-Hansen  J. The Left Atrial Appendage Closure by Surgery study (LAACS). https://www.escardio.org/The-ESC/Press-Office/Press-releases/closure-of-left-atrial-appendage-during-heart-surgery-protects-the-brain. Published 2017. Accessed October 9, 2017.
29.
Maisel  WH, Rawn  JD, Stevenson  WG.  Atrial fibrillation after cardiac surgery.  Ann Intern Med. 2001;135(12):1061-1073.PubMedGoogle ScholarCrossref
30.
Kumamaru  H, Judd  SE, Curtis  JR,  et al.  Validity of claims-based stroke algorithms in contemporary Medicare data.  Circ Cardiovasc Qual Outcomes. 2014;7(4):611-619.PubMedGoogle ScholarCrossref
31.
Tirschwell  DL, Longstreth  WT  Jr.  Validating administrative data in stroke research.  Stroke. 2002;33(10):2465-2470.PubMedGoogle ScholarCrossref
32.
Kokotailo  RA, Hill  MD.  Coding of stroke and stroke risk factors using International Classification of Diseases, revisions 9 and 10.  Stroke. 2005;36(8):1776-1781.PubMedGoogle ScholarCrossref
33.
Jensen  PN, Johnson  K, Floyd  J, Heckbert  SR, Carnahan  R, Dublin  S.  A systematic review of validated methods for identifying atrial fibrillation using administrative data.  Pharmacoepidemiol Drug Saf. 2012;21(suppl 1):141-147.PubMedGoogle ScholarCrossref
34.
Noseworthy  PA, Yao  X, Abraham  NS, Sangaralingham  LR, McBane  RD, Shah  ND.  Direct comparison of dabigatran, rivaroxaban, and apixaban for effectiveness and safety in nonvalvular atrial fibrillation.  Chest. 2016;150(6):1302-1312.PubMedGoogle ScholarCrossref
35.
Yao  X, Shah  ND, Sangaralingham  LR, Gersh  BJ, Noseworthy  PA.  Non-vitamin K antagonist oral anticoagulant dosing in patients with atrial fibrillation and renal dysfunction.  J Am Coll Cardiol. 2017;69(23):2779-2790.PubMedGoogle ScholarCrossref
36.
Fan  J, Arruda-Olson  AM, Leibson  CL,  et al.  Billing code algorithms to identify cases of peripheral artery disease from administrative data.  J Am Med Inform Assoc. 2013;20(e2):e349-e354.PubMedGoogle ScholarCrossref
37.
Yao  X, Tangri  N, Gersh  BJ,  et al.  Renal outcomes in anticoagulated patients with atrial fibrillation.  J Am Coll Cardiol. 2017;70(21):2621-2632.PubMedGoogle ScholarCrossref
If you are not a JN Learning subscriber, you can either:
Subscribe to JN Learning for one year
Buy this activity
jn-learning_Modal_LoginSubscribe_Purchase
Close
If you are not a JN Learning subscriber, you can either:
Subscribe to JN Learning for one year
Buy this activity
jn-learning_Modal_LoginSubscribe_Purchase
Close
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Education Center Collection Sign In Modal Right
Close

Name Your Search

Save Search
Close
With a personal account, you can:
  • Track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
jn-learning_Modal_SaveSearch_NoAccess_Purchase
Close

Lookup An Activity

or

Close

My Saved Searches

You currently have no searches saved.

Close
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Education Center Collection Sign In Modal Right
Close