An examination of the causes and workup of Syncope. Adam Pyle MD CCFP Lecturer-University of Toronto Assistant Professor-Queen s University

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1 An examination of the causes and workup of Syncope Adam Pyle MD CCFP Lecturer-University of Toronto Assistant Professor-Queen s University ER Rounds LH 2016

2 - I have no conflicts to report

3 1. To review the causes of syncope as well as their frequencies 2. To examine the relative merits of diagnostic tests for syncope also age considerations 3. To review cases of syncope at LH 4. To remain GCS 13 or greater

4 Epidemiology 1,2 6% of hospital admits Up to 3% of ED visits Experienced by 12-40% of young adults (less than 40) 6% annual incidence in those over 75 years old

5 Etiology of Syncope 3 Noncardiac Causes Vasodepressor (vasovagal, neurocardiogenic) (10-29%) Situational (e.g., micturition) Psychogenic Orthostatic (4-12%) Drug induced (2-9%) Carotid sinus sensitivity Seizure (exclude by most syncope studies) Neuralgias trigeminal, glossopharyngeal Neurologic TIA, strokes, migraines (rare)

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8 -No evidence for orthostatic changes on blood pressure including HR monitoring -Can be a normal finding in those over 65

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10 Syncope in Children - Cardiac Syncope in children is generally a benign event. There are a few rare, but serious, causes of syncope in children. These include: Hypertrophic cardiomyopathy Anomalous origin of left coronary artery Myocarditis Long QT Syndrome Cystic medial necrosis Wolff-Parkinson-White Syndrome

11 Clinicians should use the term BRUE to describe an event occurring in an infant <1 year of age when the observer reports a sudden, brief, and now resolved episode of 1 of the following: cyanosis or pallor absent, decreased, or irregular breathing marked change in tone (hyper- or hypotonia) altered level of responsiveness Moreover, clinicians should diagnose a BRUE only when there is no explanation for a qualifying event after conducting an appropriate history and physical examination CLASS B, C, D evidence ALTE

12 Based on the above data and a number of case reports of sudden death: Obtain a family history for sudden death/syncope Beware of exercise-induced syncope in children Consider obtaining an ECG even in pediatric patients with syncope ALL AGES: ECG The ECG will be diagnostic in 2-12% of syncope cases. 2

13 BHCG 20% present with hypotension if ectopic Hypotension and anemia are two noted causes of syncope Decreased mortality (increased vigilance and imaging) has led to lower numbers of syncope patients with ectopics and no other symptoms

14 Blood Work: Generally not helpful. One study found no abnormal lab findings other than those which would be readily identified on physical exam (hypoglycemia, profound anemia). 7

15 Testing beyond the ED: Holter monitor Helpful in a small minority of patients. In one series (of 1500 patients), 2% had an arrhythmia associated with near syncope while wearing the monitor. 13 Tilt Table Testing A test for autonomic instability. A positive test indicates a predisposition for vasodepressor syncope. Isoproterenol, a sympathomimetic can be used in low doses to increase the sensitivity of the test. Patients can have false positive results from 25-80% of the time.

16 Electrophysiologic Studies (EPS) An invasive procedure that involves meticulous mapping of the heart s conduction system, studies of conduction times, and can test the heart s susceptibility to ventricular arrhythmias. EPS is abnormal in 18-68% of patients with syncope of unknown cause. However, abnormal finding on EPS does not guarantee that that was what causes a patient s syncope!

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19 Physical Exam Pearls Look for injuries: serious head injuries are possible. Also look for evidence of seizure (bitten tongue, cheeks, multiple bruises). Measure orthostatic vitals They have higher yield for older pts (1) who may have orthostatic syncope, however, abnormal findings do not rule out other causes of syncope. Do a careful cardiac exam auscultate for valvular murmurs (i.e. mitral or aortic valve disease). **Any outflow murmur that increases with valsalva in syncope is hypertrophic cardiomyopathy (HCM) until proven otherwise!** Do a rectal exam for occult blood if a GI bleed is suspected based on history, Hb or hematocrit. Other investigations? Always do an ECG. Laboratory testing has low yield, so investigate strategically, based on the history and physical. Consider BhCG (ectopic), Hb (anemia), lytes (hypok, hypoca, hypomg),trop (very low yield in pts with syncope as their only symptom). Who needs a head CT? Only in adult patients where history or physical suggest SAH,TIA/stroke, or first onset of seizure disorder.

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21 The National Institute for Health and Clinical Excellence (NICE) Guideline for Management of Transient Loss of Consciousness emphasizes the value of history and physical examination findings in predicting uncomplicated faints (e.g., vasovagal episodes) and in distinguishing seizure from syncope. Uncomplicated faints are suggested by three Ps: posture (occurs during prolonged standing or history of similar episodes avoided by lying down), provoking factors (e.g., pain, procedure), and prodrome (e.g., sweating, nausea, warmth). Seizure is suggested by tongue biting, head turning during loss of consciousness, no recollection of abnormal behavior, prolonged limb jerking (lasting minutes), post-event confusion, and prodromal déjà vu. In a recent pooled analysis of data from two studies, tongue biting had a specificity of 96% and a positive likelihood ratio (LR) of 8.6 but poor sensitivity and negative LR for predicting seizure.

22 In a meta-analysis of data from >43,000 international ED patients who presented with syncope, researchers identified patient features that predicted adverse outcomes (death, hospitalization, interventional procedures due to arrhythmia, ischemia, or valvular disease). The strongest predictors were palpitations (odds ratio, 65), exertional syncope (OR, 17), heart disease (OR, 14), bleeding (OR, 13), supine syncope (OR, 8), and lack of prodrome (OR, 7). Each of these factors, except palpitations, is a well-known predictor of adverse outcomes in syncope. Palpitations have been reported previously to suggest benign or vasovagal syncope. Therefore, clinicians should have a higher degree of suspicion for adverse outcomes when patients report palpitations preceding syncope. D'Ascenzo F et al. Incidence, etiology and predictors of adverse outcomes in 43,315 patients presenting to the Emergency Department with syncope: An international meta-analysis. Int J Cardiol 2011 Dec 22;

23 Good evidence for predicting the difference between seizure and syncope

24 ED Ultrasound: Syncope preceding or accompanying abdominal pain could be due to an ectopic pregnancy, or a leaking AAA. - Volume Assessment (for hypotensive episodes) - Effusion (Beck s)

25 Watch the Bradycardia

26 Drug-Induced Syncope Appears relatively common felt to be responsible for 13% of 70 syncope cases referred to Duke University s Syncope Clinic. 6 Drug to be considered: Beta-blockers Nitrates Calcium channel blockers Ace inhibitors Phenothiazines Antiarrhythmics Diuretics Digoxin Insulin Drugs of abuse

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28 Survival was worst for patients with a cardiovascular cause of syncope. P<0.001 for the comparison between participants with and those without syncope. The category "Vasovagal and other causes" includes vasovagal, orthostatic, medication-induced, and other, infrequent cause of syncope. Sorteriades, ES, Evans, JC, Larson, MG, et al. Incidence and prognosis of syncope. N Engl J Med 2002; 347:878.

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30 The Economic Burden of Syncope: 7 The overall cost per hospital admission was estimated to be about $5,300 in 1996 One study found to be $17,000 of unnecessary testing to diagnose vasodepressor syncope Overall, cost in United States estimated to be in excess of $1 billion

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33 Signs and Symptoms: Seizure versus syncope Though often not an issue, there are many cases when it is difficult to be sure whether a spell was syncope or a seizure. One study compared 41 seizure patients with 53 non seizure patients. They found the following associations: 8 Seizure Not a Seizure Frothing at mouth Sweating prior to episode Tongue biting Nausea prior to episode Disorientation (postictal) Orientated after event Age < 45 years Age > 45 years LOC over 5 minutes In a separate study on tongue biting, this was found only in the seizure patients (99% specifically), but it s absence did not exclude the possibility of a seizure (24% sensitivity). 9

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36 Cardiac Causes - Obstruction to flow (3-11%) Subaortic stenosis Aortic valve stenosis Mitral valve stenosis Myxoma (rare) Pulmonic valve stenosis Pulmonary emboli Pulmonary hypertension AMI Pericardial tamponade Aortic dissection

37 Cardiac Causes Arrhythmias (5-30%) Tachyarrhythmias Supraventricular tachycardia Ventricular tachycardia Bradyarrhythmias Atrial ventricular block Sick sinus syndrome Pacemaker malfunction

38 Especially important in children (diagnostic bias) Brugada WPW Long QT HOCM

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41 Orthostatic Hypotension Generally defined as a drop in blood pressure of > 20 mmhg on standing Beware! Orthostatic hypotension is present in about 40% of patients over 70 years old. Up to 23% of patients younger than 60 have orthostatic blood pressure drops. If you are able to reproduce the patient s symptoms on standing, this is helpful (regardless of the measurements). 11

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45 When to admit: a) History CHF, ventricular arrhythmias b) Scenario consistent with ACS c) Evidence of CHF or valvular heart disease d) Abnormal ECG Consider admission if: a) Age > 60 b) Hx CAD, congenital heart disease c) Family history of sudden death d) Exertional syncope

46 Level A recommendation: Obtain a standard 12-lead ECG in patients with syncope. Level A recommendation: Use history or physical examination findings consistent with heart failure to help identify patients at higher risk of an adverse outcome. Level B recommendation: 1) Consider older age, structural heart disease, or a history of coronary artery disease as risk factors for adverse outcome. 2) Consider younger patients with syncope that is nonexertional, without history or signs of cardiovascular disease, a family history of sudden death, and without comorbidities to be at low risk of adverse events. Level B recommendation: 1) Admit patients with syncope and evidence of heart failure or structural heart disease. 2) Admit patients with syncope and other factors that lead to stratification as high-risk for adverse outcome (see Risk Factors for Adverse Outcomes). Level C recommendation: Laboratory testing and advanced investigative testing such as echocardiography or cranial CT scanning need not be routinely performed unless guided by specific findings in the history or physical examination.

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49 Consider it if more than once incident and/or not explained as clearly vasovagal

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52 45 year old woman with palpitations and feeling unwell all day No CP, no SOB, no NVD Hx. HTN No meds Syncope x 1 in ER waiting room, no HI HR: 152 BP: 150/90 O2: 95% RR: 16 T: 36.6

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54 18 year old girl with syncopal episode at Timmy s (workplace) Clear prodrome, had not eaten much all day Hot in restaurant back area Q waves in lead 2, 3, No CP, no SOB, no Fam. Hx. Cardiac Death No Murmurs

55 Less than 50% of patients will have a clear etiology for a syncope spell. While many causes of syncope are benign, potential life threats including cardiac causes must be considered. Risk stratification aids in disposition of patient can be effectively stratified based on age, medical history, physical examination and ECG.

56 Dr. Poopsie takes questions

57 1) Kapoor WN: Evaluation and outcome of patients with syncope. Medicine 1990;69: ) Kapoor WN, Karpf M, Wieand S, et al: A prospective evaluation and follow-up of patients with syncope. NEJM, July 1983;309(4): ) Kapoor WN: Evaluation and management of the patient with syncope. JAMA 1992;268(18): ) Jahangir A, Smars PA, Decker WW, et al: Differential clinical predictors of bradyarrhythmia vs tachyarrhythmia in patients with cardiogenic syncope. [Abstract] Circulation 100(18) Nov 2, 1999; I721-I722. 5) Driscoll DJ, Jacobsen SJ, Porter CJ, Wollan PC: Syncope in Children and Adolescents. J Am Coll Cardiol 1997;29: ) Hanlon JT, Linzer M, MacMillian JP, et al: Syncope and presyncope associated with probable adverse drug reactions. Arch Int Med 150: ) Eagle KA, Black HR: The impact of diagnostic tests in evaluating patients with syncope. Yale J Biol Med 1983;56:1-8. 8) Hoefnagels WAJ, Padberg GW, Overweg J, et al: Transient loss of consciousness: the value of the history for distinguishing seizure from syncope. J Neurol 1991;238: ) Benbadis SR, Wolgamuth BR, Goren H, et al: Value of tongue biting in the diagnosis of seizures. Arch Int Med 1995;155: ) 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 Cadiol 1993;21: ) Atkins D, Hanusa B, Sefcik T, Kapoor W: Syncope and orthostatic hypertension. Am J Med 1990;91: ) Martin TP, Hanusa BH, Kapoor WN: Risk stratification of patients with syncope. Ann Emerg Med 1997;29(4): ) Gibson TC, Heitzman MR: Diagnostic efficacy of 24-hour electrocardiographic monitoring for syncope. Am J Card, April 1984;53(8): ) American College of Emergency Physicians. Clinical policy: critical issues in the evaluation and management of patients presenting with syncope. Ann Emerg Med June 2001;37: