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Syncope A Diagnostic and Treatment Strategy Syncope: Transient Loss of Consciousness (TLOC) Syncope  Sudden transient loss of consciousness with associated loss of postural tone  Recovery is spontaneous without neurologic deficit and without requiring electrical or chemical cardioversion  Generally a fall in systolic blood pressure below 70 mmHg or a mean arterial pressure of 40 mmHg results in loss of consciousness  Cerebral blood flow usually decreases with aging, making the elderly at higher risk for syncope Syncope  Syncope as a symptoms can be caused by a variety of medical diseases that produce a transient interruption of cerebral blood flow  A genuine effort should be made to determine a specific cause of syncope as identifying a specific cause can help in the selection of therapy, prevent recurrences, minimize expensive evaluations, and decrease morbidity  Patients with cardiac syncope have higher rates of mortality and sudden death at follow up  Identifying and treating cardiac syncope can improve outcome Classification of Transient Loss of Consciousness (TLOC) Real or Apparent TLOC Syncope Disorders Mimicking Syncope • Neurally-mediated reflex • With loss of consciousness, i.e., • Orthostatic hypotension • Cardiac arrhythmias • Structural cardiovascular • Without loss of consciousness, syndromes disease Brignole M, et al Europace, 2004;6:467-537 seizure disorders, concussion i.e., psychogenic “pseudosyncope” Syncope – A Symptom, Not a Diagnosis  Self-limited loss of consciousness and postural tone  Relatively rapid onset  Variable warning symptoms  Spontaneous, complete, and usually prompt recovery without medical or surgical intervention Underlying Underlying mechanism mechanism is is transient transient global global cerebral cerebral hypoperfusion hypoperfusion Brignole M, et al Europace, 2004;6:467-537 Presentation Overview I Etiology, Prevalence, Impact II Diagnosis III Specific Conditions and Treatment IV Special Issues Section I: Etiology, Prevalence, Impact Causes of True Syncope NeurallyNeurallyMediated Mediated Orthostatic Orthostatic • VVS • CSS • Situational Cough PostMicturition • Drug-Induced • ANS Failure Primary Secondary Cardiac Cardiac Arrhythmia Arrhythmia • Brady SN Dysfunction AV Block • Tachy VT SVT • Long QT Syndrome Unexplained Causes = Approximately 1/3 DG Benditt, MD U of M Cardiac Arrhythmia Center Structural Structural CardioCardioPulmonary Pulmonary • Acute Myocardial Ischemia • Aortic Stenosis • HCM • Pulmonary Hypertension • Aortic Dissection Syncope Mimics  Acute intoxication (e.g., alcohol)  Seizures  Sleep disorders  Somatization disorder (psychogenic pseudo-syncope)  Trauma/concussion  Hypoglycemia  Hyperventilation Brignole M, et al Europace, 2004;6:467-537 Role of Pacing as Therapy for Syncope: Summary  Three earlier studies single blind – Bias?  Pacemaker implantation may modulate reflex syncope and autonomic responses1  Study results may differ based on pre-implant selection criteria and tilt-testing techniques  Pacing therapy is effective in some but not all (cardioinhibition vs vasodepression)  In five pacing studies, syncope recurred in 33/156 (21%) of paced patients, 72/162 (44%) in non-paced patients (p Age 65 *Carotid Sinus Hypersensitivity J Am Geriatr Soc 1995 Richardson D, et al PACE 1997;20:820 Recurrence CSH* Present in Fallers > Age 50 Presenting at ER CSS Role of Pacing – Syncope Recurrence Rate Class I indication for pacing (AHA and BPEG) Limit pacing to CSS that is: • Cardioinhibitory • Mixed  DDD/DDI superior to VVI • Mean follow-up = months Brignole M, et al Eur JCPE 1992;4:247-254 % Recurrence  57% %6  SAFE PACE Syncope And Falls in the Elderly – Pacing And Carotid Sinus Evaluation   Objective  Results • Determine whether cardiac • More than 1/3 of adults over pacing reduces falls in older adults with carotid sinus hypersensitivity 50 years presented to the Emergency Department because of a fall Randomized controlled trial (N=175) • Adults > 50 years, non-accidental fall, positive CSM • Pacing (n=87) vs No Pacing (n=88) Kenny RA J Am Coll Cardiol 2001;38:1491-1496 • With pacing, falls  70% • Syncopal events  53% • Injurious events  70% SAFE PACE  Conclusions • Strong association between non-accidental falls and cardioinhibitory CSH • These patients usually not referred for cardiac assessment • Cardiac pacing significantly reduced subsequent falls • CSH should be considered in all older adults who have non-accidental falls Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496 Orthostatic Hypotension  Etiology  Drug-induced (very common)   Secondary autonomic failure • Diabetes • Diuretics • Alcohol • Vasodilators • Amyloid Primary autonomic failure • Multiple system atrophy • Parkinson’s Disease • Postural Orthostatic Tachycardia Syndrome (POTS) Brignole M, et al Europace, 2004;6:467-537 Treatment Strategies for Orthostatic Intolerance  Patient education, injury avoidance  Hydration • Fluids, salt, diet • Minimize caffeine/alcohol  Sleeping with head of bed elevated  Tilt training, leg crossing, arm pull  Support hose  Drug therapies • Fludrocortisone, midodrine, erythropoietin  Tachy-Pacing (probably not useful) Brignole M, et al Europace, 2004;6:467-537 Section IV: Special Issues Syncope: Diagnostic Testing in Hospital Strongly Recommended  Suspected/known ‘significant’ heart disease  ECG abnormalities suggesting potential life-threatening arrhythmic cause  Syncope during exercise  Severe injury or accident  Family history of premature sudden death Brignole M, et al Europace 2004;6:467-537 SEEDS: Syncope Evaluation in the Emergency Department Study Long-Term Clinical Outcomes Survival Free from Death Survival Free from Recurrence 100% 100% 90% 90% Syncope Unit Group 80% Syncope Unit Group 80% Standard Care Group Standard Care Group P=0.30 P=0.72 70% 70% Years Years Results:  Syncope unit improved diagnostic yield in the ED and reduced hospital admission and length of stay Shen W, et al Circ 2004;110(24):3636-3645 The Integrated Syncope Unit  To optimize the effectiveness of the evaluation and treatment of syncope patients at a given center  Best accomplished by: • Cohesive, structured care pathway • Multidisciplinary approach • Core equipment available • Preferential access to other tests or therapy  Majority of syncope evaluations – Out-patient or day cases Kenny RA, Brignole M In: Benditt D, et al eds The Evaluation and Treatment of Syncope Futura;2003:55-60 Brignole M, et al Europace, 2004;6:467-537 Conclusion  Syncope is a common symptom with many causes  Deserves thorough investigation and appropriate treatment  A disciplined approach is essential  AHA/ACCF and ESC guidelines offer current best practices Brignole M, et al Europace, 2004;6:467-537 Challenges of Syncope  Cost  Quality of life implications  Diagnosis and treatment • Diagnostic yield and repeatability of tests • Frequency and clustering of events • Difficulty in managing/treating/controlling future events • Appropriate risk stratification • Complex etiology Olshansky B In: Grubb B and Olshansky B eds Syncope: Mechanisms and Management Futura 1998:15-71 Brignole M, et al Europace, 2004;6:467-537