Management of syncope in adults
- David Benditt, MD
David Benditt, MD
- Professor of Medicine
- Director, Cardiac Arrhythmia Center
- University of Minnesota Medical School
Syncope is the abrupt and transient loss of consciousness associated with loss of postural tone, followed by complete and usually rapid spontaneous recovery. Syncope is almost always due to temporary inadequacy of cerebral perfusion. Although it can be alarming for the individual, witnesses, family, and physicians, syncope is most often benign and self-limited. Nevertheless, injuries associated with syncopal attacks occur in 35 percent of patients, and recurrent episodes can be psychologically devastating. In addition, syncope can be a premonitory sign of cardiac arrest, especially in patients with organic heart disease.
Issues relating to the management of the patient with syncope will be reviewed here. The pathogenesis, etiology, and the evaluation of this disorder are discussed elsewhere. (See "Pathogenesis and etiology of syncope" and "Syncope in adults: Clinical manifestations and diagnostic evaluation".)
The management of the patient with syncope is the same as that for presyncope, which is the prodromal symptom of fainting. Such patients usually present with symptoms of dizziness. (See "Approach to the patient with dizziness".)
Treatment is based upon the underlying cause of syncope (table 1 and table 2) and is directed at preventing recurrence and/or, in some cases, death. A brief review of the available treatment options for each of the possible underlying disorders is presented below. Detailed discussions of the treatment of individual disorders are presented separately. The treatment options discussed are in general agreement with guidelines published in 2009 by a task force of the European Society of Cardiology .
Metabolic disorders — Although metabolic abnormalities (such as hypoglycemia or hypoxia) infrequently cause syncope, they can cause impaired consciousness that may be difficult to distinguish from syncope. Metabolic abnormalities, anemia, and hypovolemia can be effectively managed by specific therapy to correct these abnormalities.
- Task Force for the Diagnosis and Management of Syncope, European Society of Cardiology (ESC), European Heart Rhythm Association (EHRA), et al. Guidelines for the diagnosis and management of syncope (version 2009). Eur Heart J 2009; 30:2631.
- Huang JJ, Sharda N, Riaz IB, Alpert JS. Summer syncope syndrome. Am J Med 2014; 127:787.
- Robertson D, Robertson RM. Causes of chronic orthostatic hypotension. Arch Intern Med 1994; 154:1620.
- Bonow RO, Rosing DR, Bacharach SL, et al. Effects of verapamil on left ventricular systolic function and diastolic filling in patients with hypertrophic cardiomyopathy. Circulation 1981; 64:787.
- Pires LA, May LM, Ravi S, et al. Comparison of event rates and survival in patients with unexplained syncope without documented ventricular tachyarrhythmias versus patients with documented sustained ventricular tachyarrhythmias both treated with implantable cardioverter-defibrillators. Am J Cardiol 2000; 85:725.
- Epstein AE, DiMarco JP, Ellenbogen KA, et al. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation 2008; 117:e350.
- Olshansky B, Poole JE, Johnson G, et al. Syncope predicts the outcome of cardiomyopathy patients: analysis of the SCD-HeFT study. J Am Coll Cardiol 2008; 51:1277.
- Mittal S, Iwai S, Stein KM, et al. Long-term outcome of patients with unexplained syncope treated with an electrophysiologic-guided approach in the implantable cardioverter-defibrillator era. J Am Coll Cardiol 1999; 34:1082.
- Krahn AD, Klein GJ, Fitzpatrick A, et al. Predicting the outcome of patients with unexplained syncope undergoing prolonged monitoring. Pacing Clin Electrophysiol 2002; 25:37.
- Kapoor WN, Peterson J, Wieand HS, Karpf M. Diagnostic and prognostic implications of recurrences in patients with syncope. Am J Med 1987; 83:700.
- Malik P, Koshman ML, Sheldon R. Timing of first recurrence of syncope predicts syncopal frequency after a positive tilt table test result. J Am Coll Cardiol 1997; 29:1284.
- Numé AK, Gislason G, Christiansen CB, et al. Syncope and Motor Vehicle Crash Risk: A Danish Nationwide Study. JAMA Intern Med 2016; 176:503.
- Dischinger PC, Ho SM, Kufera JA. Medical conditions and car crashes. Annu Proc Assoc Adv Automot Med 2000; 44:335.
- Redelmeier DA, Yarnell CJ, Thiruchelvam D, Tibshirani RJ. Physicians' warnings for unfit drivers and the risk of trauma from road crashes. N Engl J Med 2012; 367:1228.
- Epstein AE, Miles WM, Benditt DG, et al. Personal and public safety issues related to arrhythmias that may affect consciousness: implications for regulation and physician recommendations. A medical/scientific statement from the American Heart Association and the North American Society of Pacing and Electrophysiology. Circulation 1996; 94:1147.
- Epstein AE, Baessler CA, Curtis AB, et al. Addendum to "Personal and public safety issues related to arrhythmias that may affect consciousness: implications for regulation and physician recommendations: a medical/scientific statement from the American Heart Association and the North American Society of Pacing and Electrophysiology": public safety issues in patients with implantable defibrillators: a scientific statement from the American Heart Association and the Heart Rhythm Society. Circulation 2007; 115:1170.
- Middlekauff HR, Stevenson WG, Stevenson LW, Saxon LA. Syncope in advanced heart failure: high risk of sudden death regardless of origin of syncope. J Am Coll Cardiol 1993; 21:110.
- Kapoor WN, Karpf M, Wieand S, et al. A prospective evaluation and follow-up of patients with syncope. N Engl J Med 1983; 309:197.
- Eagle KA, Black HR, Cook EF, Goldman L. Evaluation of prognostic classifications for patients with syncope. Am J Med 1985; 79:455.
- Morady F, Shen E, Schwartz A, et al. Long-term follow-up of patients with recurrent unexplained syncope evaluated by electrophysiologic testing. J Am Coll Cardiol 1983; 2:1053.
- Oh JH, Hanusa BH, Kapoor WN. Do symptoms predict cardiac arrhythmias and mortality in patients with syncope? Arch Intern Med 1999; 159:375.
- DERMKSIAN G, LAMB LE. Syncope in a population of healthy young adults; incidence, mechanisms, and significance. J Am Med Assoc 1958; 168:1200.
- Kapoor W, Karpf M, Levey GS. Issues in evaluating patients with syncope. Ann Intern Med 1984; 100:755.
- WAYNE HH. Syncope. Physiological considerations and an analysis of the clinical characteristics in 510 patients. Am J Med 1961; 30:418.
- Costantino G, Perego F, Dipaola F, et al. Short- and long-term prognosis of syncope, risk factors, and role of hospital admission: results from the STePS (Short-Term Prognosis of Syncope) study. J Am Coll Cardiol 2008; 51:276.
- Middlekauff HR, Stevenson WG, Saxon LA. Prognosis after syncope: impact of left ventricular function. Am Heart J 1993; 125:121.
- Soteriades ES, Evans JC, Larson MG, et al. Incidence and prognosis of syncope. N Engl J Med 2002; 347:878.
- Silverstein MD, Singer DE, Mulley AG, et al. Patients with syncope admitted to medical intensive care units. JAMA 1982; 248:1185.
- Freed LA, Eagle KA, Mahjoub ZA, et al. Gender differences in presentation, management, and cardiac event-free survival in patients with syncope. Am J Cardiol 1997; 80:1183.
- Metabolic disorders
- Iatrogenic syncope
- Orthostatic hypotension
- Cardiovascular disease with obstruction
- Implantable cardioverter-defibrillator therapy
- - Documented, suspected, or induced ventricular tachycardia
- - Other ICD indications
- Genetic syndromes
- Supraventricular arrhythmias
- Sinus bradycardia or AV block
- Vasovagal syncope
- Carotid sinus hypersensitivity
- RATE OF RECURRENT SYNCOPE
- DRIVING RESTRICTIONS
- Underlying cardiovascular disease
- SUMMARY AND RECOMMENDATIONS