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Etiology and prognosis of patients with unexplained syncope and mid-range left ventricular dysfunction

  • Jaume Francisco-Pascual
    Correspondence
    Address reprint requests and correspondence: Dr Jaume Francisco-Pascual, Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d’Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Passeig de la Vall Hebron 119-129, 08035 Barcelona, Spain.
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
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  • Eduard Rodenas-Alesina
    Affiliations
    Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
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  • Nuria Rivas-Gándara
    Correspondence
    Dr Nuria Rivas-Gándara, Servei de Cardiologia. Hospital Universitari Vall d’Hebron, Passeig de la Vall Hebron 119-129, 08035 Barcelona (Spain).
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
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  • Yassin Belahnech
    Affiliations
    Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
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  • Aleix Olivella San Emeterio
    Affiliations
    Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
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  • Jordi Pérez-Rodón
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
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  • Begoña Benito
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
    Search for articles by this author
  • Alba Santos-Ortega
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
    Search for articles by this author
  • Àngel Moya-Mitjans
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
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  • Guillem Casas
    Affiliations
    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain

    Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
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  • Javier Cantalapiedra-Romero
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    Universitat Autònoma de Barcelona, Bellaterra, Spain

    CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
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  • Jenson Maldonado
    Affiliations
    Unitat d'Arritmies, Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
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  • Ignacio Ferreira-González
    Affiliations
    Universitat Autònoma de Barcelona, Bellaterra, Spain

    Servei de Cardiologia, Hospital Universitari Vall d'Hebron, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain

    CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
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Published:December 14, 2020DOI:https://doi.org/10.1016/j.hrthm.2020.12.009

      Background

      Syncope in patients with mid-range left ventricular ejection fraction (LVEF) can be due to potentially serious arrhythmic causes. However, there is no clear consensus on the best way to manage these patients.

      Objectives

      The objectives of this study were to determine the causes of syncope and assess the diagnostic yield and safety of a stepwise workup protocol in this population.

      Methods

      This was a prospective observational study. A stepwise workup protocol was applied to patients with LVEF 35%–50% and unexplained syncope after the initial assessment (step 1).

      Results

      One hundred four patients were included {median age 75.6 years; (interquartile range [IQR] 67.6–81.2 years); median LVEF 45% (IQR 40%–48%); median follow-up 2.0 years (IQR 0.7–3.3 years). In 71 patients (68.3%), a diagnosis was reached: 55 (77.5%) in step 2 (hospital admission and electrophysiology study) and 16 (36.5%) in step 3 (implantable cardiac monitor). Arrhythmic causes were the most common etiology (45.2% auriculoventricular block and 9.6% ventricular tachycardia). Sixty patients (57.7%) required the implantation of a cardiac device and 11 had a defibrillation function. Patients diagnosed in step 3 had a higher global risk of recurrence of syncope (hazard ratio 6.5; 95% confidence interval 2.3–18.0). The mortality rate was 8.1 per 100 person-years, and the sudden or unknown death rate was 0.9 per 100 person-years.

      Conclusion

      In patients with mid-range left ventricular dysfunction and syncope of unknown cause, a systematic diagnostic strategy based on electrophysiology study and/or implantable cardiac monitor implantation allows a diagnosis to be reached in a high proportion of cases and guides the treatment. Arrhythmia is the most common cause of syncope in this population, particularly auriculoventricular block.

      Keywords

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      References

        • Brignole M.
        • Moya A.
        • de Lange F.J.
        • et al.
        • ESC Scientific Document Group
        2018 ESC Guidelines for the diagnosis and management of syncope.
        Eur Heart J. 2018; 39: 1883-1948
        • Phang R.S.
        • Kang D.
        • Tighiouart H.
        • Estes N.A.M.
        • Link M.S.
        High risk of ventricular arrhythmias in patients with nonischemic dilated cardiomyopathy presenting with syncope.
        Am J Cardiol. 2006; 97: 416-420
      1. Francisco-Pascual J, Rodenas-Alesina E, Belahnech-Pujol Y, et al. Syncope in patients with severe aortic stenosis: more than only an obstructive issue [published online ahead of print May 18, 2020]. Can J Cardiol. https://doi.org/10.1016/j.cjca.2020.04.047.

        • Ruwald M.H.
        • Okumura K.
        • Kimura T.
        • et al.
        Syncope in high-risk cardiomyopathy patients with implantable defibrillators: frequency, risk factors, mechanisms, and association with mortality: results from the Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy (MADIT-RIT) Study.
        Circulation. 2014; 129: 545-552
        • Shen W.K.
        • Sheldon R.S.
        • Benditt D.G.
        • et al.
        2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society.
        Circulation. 2017; 136: e60-e122
        • Brignole M.
        • Arabia F.
        • Ammirati F.
        • et al.
        Standardized algorithm for cardiac pacing in older patients affected by severe unpredictable reflex syncope: 3-year insights from the Syncope Unit Project 2 (SUP 2) study.
        Europace. 2016; 18: 1427-1433
        • Moya A.
        • García-Civera R.
        • Croci F.
        • et al.
        Diagnosis, management, and outcomes of patients with syncope and bundle branch block.
        Eur Heart J. 2011; 32: 1535-1541
        • Roca-Luque I.
        • Francisco-Pasqual J.
        • Oristrell G.
        • et al.
        Flecainide versus procainamide in electrophysiological study in patients with syncope and wide QRS duration.
        JACC Clin Electrophysiol. 2019; 5: 212-219
        • Roca-Luque I.
        • Francisco-Pascual J.
        • Oristrell G.
        • et al.
        Syncope, conduction disturbance, and negative electrophysiological test: predictive factors and risk score to predict pacemaker implantation during follow-up.
        Heart Rhythm. 2019; 16: 905-912
        • Garcia-Civera R.
        • Ruiz-Granell R.
        • Morell-Cabedo S.
        • et al.
        Selective use of diagnostic tests in patients with syncope of unknown cause.
        J Am Coll Cardiol. 2003; 41: 787-790
        • Robert Denniss A.
        • Ross D.L.
        • Richards D.A.
        • Uther J.B.
        Electrophysiologic studies in patients with unexplained syncope.
        Int J Cardiol. 1992; 35: 211-217
        • Pezawas T.
        • Stix G.
        • Kastner J.
        • et al.
        Unexplained syncope in patients with structural heart disease and no documented ventricular arrhythmias: value of electrophysiologically guided implantable cardioverter defibrillator therapy.
        Europace. 2003; 5: 305-312
        • Shenthar J.
        • Prabhu M.A.
        • Banavalikar B.
        • Benditt D.G.
        • Padmanabhan D.
        Etiology and outcomes of syncope in patients with structural heart disease and negative electrophysiology study.
        JACC Clin Electrophysiol. 2019; 5: 608-617
        • Link M.S.
        • Kim K.M.S.
        • Homoud M.K.
        • Estes N.A.M.
        • Wang P.J.
        Long-term outcome of patients with syncope associated with coronary artery disease and a nondiagnostic electrophysiologic evaluation.
        Am J Cardiol. 1999; 83: 1334-1337
        • Moya A.
        • Rivas-Gandara N.
        • Perez-Rodón J.
        • et al.
        Syncope and bundle branch block: diagnostic approach.
        Herzschrittmacherther Elektrophysiol. 2018; 29: 161-165
        • Roca-Luque I.
        • Oristrell G.
        • Francisco-Pasqual J.
        • et al.
        Predictors of positive electrophysiological study in patients with syncope and bundle branch block: PR interval and type of conduction disturbance.
        Clin Cardiol. 2018; 41: 1537-1542
        • Solbiati M.
        • Casazza G.
        • Dipaola F.
        • et al.
        The diagnostic yield of implantable loop recorders in unexplained syncope: a systematic review and meta-analysis.
        Int J Cardiol. 2017; 231: 170-176
        • Francisco-Pascual J.
        • Olivella San Emeterio A.
        • Rivas-Gándara N.
        • et al.
        High incidence of subclinical atrial fibrillation in patients with syncope monitored with implantable cardiac monitor.
        Int J Cardiol. 2020; 316: 110-116
        • Solano A.
        • Menozzi C.
        • Maggi R.
        • et al.
        Incidence, diagnostic yield and safety of the implantable loop-recorder to detect the mechanism of syncope in patients with and without structural heart disease.
        Eur Heart J. 2004; 25: 1116-1119
        • Menozzi C.
        • Brignole M.
        • Garcia-Civera R.
        • et al.
        Mechanism of syncope in patients with heart disease and negative electrophysiologic test.
        Circulation. 2002; 105: 2741-2745
        • Chioncel O.
        • Lainscak M.
        • Seferovic P.M.
        • et al.
        Epidemiology and one-year outcomes in patients with chronic heart failure and preserved, mid-range and reduced ejection fraction: an analysis of the ESC Heart Failure Long-Term Registry.
        Eur J Heart Fail. 2017; 19: 1574-1585
        • Bhambhani V.
        • Kizer J.R.
        • Lima J.A.C.
        • et al.
        Predictors and outcomes of heart failure with mid-range ejection fraction.
        Eur J Heart Fail. 2018; 20: 651-659
        • Hsu J.J.
        • Ziaeian B.
        • Fonarow G.C.
        Heart failure with mid-range (borderline) ejection fraction: clinical implications and future directions.
        JACC Heart Fail. 2017; 5: 763-771
        • Avula H.R.
        • Leong T.K.
        • Lee K.K.
        • Sung S.H.
        • Go A.S.
        Long-term outcomes of adults with heart failure by left ventricular systolic function status.
        Am J Cardiol. 2018; 122: 1008-1016
        • Halliday B.P.
        • Gulati A.
        • Ali A.
        • et al.
        Association between midwall late gadolinium enhancement and sudden cardiac death in patients with dilated cardiomyopathy and mild and moderate left ventricular systolic dysfunction.
        Circulation. 2017; 135: 2106-2115
        • Merlo M.
        • Gentile P.
        • Artico J.
        • et al.
        Arrhythmic risk stratification in patients with dilated cardiomyopathy and intermediate left ventricular dysfunction.
        J Cardiovasc Med. 2019; 20: 343-350