Implantable loop recorders in patients with unexplained syncope: Clinical predictors of pacemaker implantation
Abstract
Background: Implantable loop recorders (ILR) are a valuable tool for the investigation of unexplained syncopal episodes. The aim of this retrospective single center study was to identify predictive factors for pacemaker implantation in patients with unexplained syncope who underwent ILR insertion.
Methods: One hundred six patients were retrospectively analyzed (mean age 59.1 years; 47.2% male) with unexplained syncope and negative conventional testing who underwent ILR implantation. The pri- mary study endpoint was detection of symptomatic or asymptomatic bradycardia requiring pacemaker implantation.
Results: The average follow-up period after ILR implantation was 20 ± 15 months. Pacemaker im- plantation according to current guidelines was necessary in 22 (20.8%) patients, mean duration until index bradycardia was 81 ± 88 (2–350) days. Ten (45.5%) patients received a pacemaker due to sinus arrest, 7 (31.8%) patients due to third-degree atrioventricular block, 2 (9.1%) patients due to second- degree atrioventricular block and 1 (4.5%) patient due to atrial fibrillation with a slow ventricular rate. Three factors remained significant in multivariate analysis: obesity, which defined by a body mass index above 30 kg/m2 (OR: 7.39, p = 0.014), a right bundle branch block (OR: 9.40, p = 0.023) and chronic renal failure as defined by a glomerular filtration rate of less than 60 mL/min (OR: 6.42, p = 0.035).
Conclusions: Bradycardia is a frequent finding in patients undergoing ILR implantation due to un- explained syncope. Obesity, right bundle branch block and chronic renal failure are independent clinical predictors of pacemaker implantation
Keywords: implantable loop recorderunexplained syncopepacemaker
References
- Soteriades ES, Evans JC, Larson MG, et al. Incidence and prognosis of syncope. N Engl J Med. 2002; 347(12): 878–885.
- Rose MS, Koshman ML, Spreng S, et al. The relationship between health-related quality of life and frequency of spells in patients with syncope. J Clin Epidemiol. 2000; 53(12): 1209–1216.
- Sutton R, Benditt DG. Epidemiology and economic impact of cardiac syncope in western countries. Future Cardiol. 2012; 8(3): 467–472.
- Colman N, Nahm K, Ganzeboom KS, et al. Epidemiology of reflex syncope. Clin Auton Res. 2004; 14 Suppl 1: 9–17.
- Moya A, Sutton R, Ammirati F, et al. Task Force for the Diagnosis and Management of Syncope, European Society of Cardiology (ESC), European Heart Rhythm Association (EHRA), Heart Failure Association (HFA), Heart Rhythm Society (HRS). Guidelines for the diagnosis and management of syncope (version 2009). Eur Heart J. 2009; 30(21): 2631–2671.
- Parry SW, Matthews IG. Implantable loop recorders in the investigation of unexplained syncope: a state of the art review. Heart. 2010; 96(20): 1611–1616.
- Paruchuri V, Adhaduk M, Garikipati NV, et al. Clinical utility of a novel wireless implantable loop recorder in the evaluation of patients with unexplained syncope. Heart Rhythm. 2011; 8(6): 858–863.
- Farwell DJ, Freemantle N, Sulke N. The clinical impact of implantable loop recorders in patients with syncope. Eur Heart J. 2006; 27(3): 351–356.
- Edvardsson N, Frykman V, van Mechelen R, et al. PICTURE Study Investigators. Use of an implantable loop recorder to increase the diagnostic yield in unexplained syncope: results from the PICTURE registry. Europace. 2011; 13(2): 262–269.
- Brignole M, Sutton R, Menozzi C, et al. Early application of an implantable loop recorder allows effective specific therapy in patients with recurrent suspected neurally mediated syncope. Eur Heart J. 2006; 27(9): 1085–1092.
- Brignole M, Auricchio A, Baron-Esquivias G, et al. 2013 ESC Guidelines on cardiac pacing and cardiac resynchronization therapy: the Task Force on cardiac pacing and resynchronization therapy of the European Society of Cardiology (ESC). Developed in collaboration with the European Heart Rhythm Association (EHRA). Eur Heart J. 2013; 34(29): 2281–2329.
- Palmisano P, Accogli M, Zaccaria M, et al. Predictive factors for pacemaker implantation in patients receiving an implantable loop recorder for syncope remained unexplained after an extensive cardiac and neurological workup. Int J Cardiol. 2013; 168(4): 3450–3457.
- Ahmed N, Frontera A, Carpenter A, et al. Clinical Predictors of Pacemaker Implantation in Patients with Syncope Receiving Implantable Loop Recorder with or without ECG Conduction Abnormalities. Pacing Clin Electrophysiol. 2015; 38(8): 934–941.
- Vardas PE, Auricchio A, Blanc JJ, et al. European Society of Cardiology, European Heart Rhythm Association. Guidelines for cardiac pacing and cardiac resynchronization therapy: The Task Force for Cardiac Pacing and Cardiac Resynchronization Therapy of the European Society of Cardiology. Developed in collaboration with the European Heart Rhythm Association. Eur Heart J. 2007; 28(18): 2256–2295.
- Lacunza-Ruiz FJ, Moya-Mitjans A, Martínez-Alday J, et al. Implantable loop recorder allows an etiologic diagnosis in one-third of patients. Results of the Spanish reveal registry. Circ J. 2013; 77(10): 2535–2541.
- Anand IS. Cardiorenal syndrome: a cardiologist's perspective of pathophysiology. Clin J Am Soc Nephrol. 2013; 8(10): 1800–1807.
- Shamseddin MK, Parfrey PS. Sudden cardiac death in chronic kidney disease: epidemiology and prevention. Nat Rev Nephrol. 2011; 7(3): 145–154.
- Sherif KA, Abo-Salem E, Panikkath R, et al. Cardiac repolarization abnormalities among patients with various stages of chronic kidney disease. Clin Cardiol. 2014; 37(7): 417–421.
- Parekh RS, Plantinga LC, Kao WH, et al. The association of sudden cardiac death with inflammation and other traditional risk factors. Kidney Int. 2008; 74(10): 1335–1342.
- Kadappu KK, Kuncoro AS, Hee L, et al. Chronic kidney disease is independently associated with alterations in left atrial function. Echocardiography. 2014; 31(8): 956–964.
- Panoulas VF, Sulemane S, Konstantinou K, et al. Early detection of subclinical left ventricular myocardial dysfunction in patients with chronic kidney disease. Eur Heart J Cardiovasc Imaging. 2015; 16(5): 539–548.
- Edwards NC, Moody WE, Yuan M, et al. Diffuse interstitial fibrosis and myocardial dysfunction in early chronic kidney disease. Am J Cardiol. 2015; 115(9): 1311–1317.
- Adar A, Kiriş A, Ulusoy S, et al. Fragmented QRS is associated with subclinical left ventricular dysfunction in patients with chronic kidney disease. Acta Cardiol. 2014; 69(4): 385–390.
- Laszki-Szcząchor K, Zwolińska D, Sobieszczańska M, et al. Dynamics of changes in heart conduction system in dialyzed young adults after kidney transplantation--pilot study. Transplant Proc. 2014; 46(8): 2708–2713.
- Hubert HB, Feinleib M, McNamara PM, et al. Obesity as an independent risk factor for cardiovascular disease: a 26-year follow-up of participants in the Framingham Heart Study. Circulation. 1983; 67(5): 968–977.
- Dublin S, French B, Glazer NL, et al. Risk of new-onset atrial fibrillation in relation to body mass index. Arch Intern Med. 2006; 166(21): 2322–2328.
- Abel ED, Litwin SE, Sweeney G. Cardiac remodeling in obesity. Physiol Rev. 2008; 88(2): 389–419.
- Csepe TA, Kalyanasundaram A, Hansen BJ, et al. Fibrosis: a structural modulator of sinoatrial node physiology and dysfunction. Front Physiol. 2015; 6: 37.
- Albarado-Ibañez A, Avelino-Cruz JE, Velasco M, et al. Metabolic syndrome remodels electrical activity of the sinoatrial node and produces arrhythmias in rats. PLoS One. 2013; 8(11): e76534.
- Yanni J, Tellez JO, Sutyagin PV, et al. Structural remodelling of the sinoatrial node in obese old rats. J Mol Cell Cardiol. 2010; 48(4): 653–662.
- Shin SY, Yong HS, Lim HE, et al. Total and interatrial epicardial adipose tissues are independently associated with left atrial remodeling in patients with atrial fibrillation. J Cardiovasc Electrophysiol. 2011; 22(6): 647–655.
- Yanni J, Maczewski M, Mackiewicz U, et al. Structural and functional alterations in the atrioventricular node and atrioventricular ring tissue in ischaemia-induced heart failure. Histol Histopathol. 2014; 29(7): 891–902.
- Joshy G, Korda RJ, Attia J, et al. Body mass index and incident hospitalisation for cardiovascular disease in 158 546 participants from the 45 and Up Study. Int J Obes (Lond). 2014; 38(6): 848–856.
- Grimm W, Becker HF. Obesity, sleep apnea syndrome, and rhythmogenic risk. Herz. 2006; 31(3): 213–8; quiz 219.
- Schweitzer P. Cardiac arrhythmias in obstructive sleep apnea. Vnitr Lek. 2008; 54(10): 1006–1009.
- 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(12): 1535–1541.
- Santini M, Castro A, Giada F, et al. Prevention of syncope through permanent cardiac pacing in patients with bifascicular block and syncope of unexplained origin: the PRESS study. Circ Arrhythm Electrophysiol. 2013; 6(1): 101–107.
- Tabrizi F, Rosenqvist M, Bergfeldt L, et al. Time relation between a syncopal event and documentation of atrioventricular block in patients with bifascicular block: clinical implications. Cardiology. 2007; 108(2): 138–143.
- Sud S, Klein GJ, Skanes AC, et al. Predicting the cause of syncope from clinical history in patients undergoing prolonged monitoring. Heart Rhythm. 2009; 6(2): 238–243.
- Kadmon E, Menachemi D, Kusniec J, et al. Clinical experience of two Israeli medical centers with the implantable loop recorder in patients with syncope: from diagnosis to treatment. Isr Med Assoc J. 2012; 14(8): 488–492.
- Furukawa T, Maggi R, Bertolone C, et al. Additional diagnostic value of very prolonged observation by implantable loop recorder in patients with unexplained syncope. J Cardiovasc Electrophysiol. 2012; 23(1): 67–71.
- Solbiati M, Bozzano V, Barbic F, et al. Syncope recurrence and mortality: a systematic review. Europace. 2015; 17(2): 300–308.
- Martínez P, Pilar Sáez M, Rubio JA, et al. [Experience with the use of an implantable loop recorder in a series of older people with falls and suspected arrhythmic syncopes]. Rev Esp Geriatr Gerontol. 2014; 49(3): 121–124.
- Davis S, Westby M, Pitcher D, et al. Implantable loop recorders are cost-effective when used to investigate transient loss of consciousness which is either suspected to be arrhythmic or remains unexplained. Europace. 2012; 14(3): 402–409.