Syncope
Darius Sholevar, MD FACC
Disclosures – Research Collaboration
• Medtronic
• St. Jude
• Boston Scientific
• Angel medical systems
• Biosense Webster
Definition
- Syncope is derived from the Greek words:
syn (with) + Koptein (to cut) = to interrupt
- It is defined as a transient self limited loss of
consciousness due to transient global cerebral
hypoperfusion.
Impact of Syncope: US Trends – A Common Problem
Inpatient Trend*
Physician Office Visits**
440,000
1,200,000
420,000
1,100,000
1,000,000
400,000
900,000
380,000
800,000
360,000
700,000
340,000
600,000
320,000
500,000
300,000
400,000
1996 1997 1998 1999 2000 2001 2002
1996
1997
1998
1999
2000
2001
*All patients discharged with syncope and collapse
(ICD-9 Code:780.2) listed among diagnoses.
**Syncope and collapse (ICD-9 Code: 780.2)
listed as primary reason for visit.
NHDS 2003.
NAMCS 2002.
UNKOWN - 40%
Vasovagal Syncope – 37%
Cardiac Arrhythmias – 15%
Syncope
Orthostasis
Drug / Medication Induced
Structural Heart Disease
Loss of
Consciousness
Cerebrovascular Disease
Seizure
Pseudo-Syncope
Psychogenic Syncope
Syncope Risk by Cause
• Survival with and
without syncope
• 6-month mortality
rate of greater
than 10%
• Cardiac syncope
doubled the risk
of death
Soteriades ES, et al. NEJM . 2002;347:878-885.
N Engl J Med. Sept. 19, 2002
What to Do Next?
How To Evaluate
Syncope
Transient Cause
No testing, Treat
Cause and Avoid
History and
Physical
Neurocardiogenic
Syncope
Suspected
Suspect Cardiac
Etiology or
Structural Heart
Disease
Admission,
Rare Episodes
Frequent Episodes
Lifestyle
Modification
EKG and Referral
Cardiology
Evaluation
History – Telltale Findings
• Seizure – Aura, Tongue bites, prolonged confusion after episode,
incontinence, automatisms, hemi-lateral seizure activity, aching
muscles
• Watch out for Tonic Clinic Activity from Syncope
• Neurocardiogenic syncope – noxious stimuli, after exertion, sweating,
nausea, very brief tonic clinic movements (less than 30 seconds)
• Cardiac Etiology – history of congestive heart failure or myocardial
infarction, QT prolonging medications, episodes occurs during
exertion, family history of sudden death / SIDS
• Palpitations starting as first symptom
• Carotid sinus hypersensitivity – tight color or on head or neck turning
• Orthostasis – prolonged sitting or standing
• Psychogenic – frequent attacks with somatic complaints and negative
symptom rhythm correlation
When to Hospitalize
• Often a clinical decision
•
•
•
•
•
•
Arrhythmic, cardiovascular cause
New neurological abnormality
Multiple, frequent episodes
Severe orthostatic hypotension
Elderly patient
Treatment requiring admission
Further evaluation
• Carotid sinus massage
• ECG monitoring
• Echocardiogram
• Ambulatory ECG Monitoring
• Holter
• Event Monitor
• Implantable loop recorders
• Tilt testing
• Electrophysiological testing
• Stress Testing – syncope during exercise
Diagnostic Methods and Yields
Procedure
History and Physical Exam
Yield*
25-35%1
ECG
2-11%2
Monitoring
Holter Monitoring
2%3
External Loop Recorder
20% 3
Insertable Loop Recorder
43-88%4,5,6
Test/Procedure
Tilt Table
11-87% 1,7
EP Study without SHD**
11% 8
EP Study with SHD
49% 1
Low Yield Testing for Syncope
• Cardiac enzymes
• CT scan
• Carotid Doppler's
• Neurology consult – 0-4% diagnostic yield
• EEG
• Psychiatric consultation
Carotid Sinus Massage
• Outcome
• Positive if BP drops > 50 mmHg and/or > 3 sec. asystole1
• Absolute contraindications2
• MI, TIA, or stroke in past 3 months; carotid bruits
• Relative contraindications
• Previous VF, VT
1Kenny
2Linzer
RA. Heart. 2000;83:564.
M. Ann Intern Med. 1997;126:989.
ECG Abnormalities Predicting Cardiac Syncope
• Bradycardia less than 50
bpm
• LBBB & Bifasicular Block
• Second degree AV Block
• Third Degree AV block
• Long QT interval
• Brugada syndrome
• Pre-excitation
• Myocardial infarction
• Ventricular Arrhythmias
When to Perform a Heart Monitor
• Holter monitor is rarely indicated unless there is very frequent
syncope or dizziness
• Exception may be high suspicion of frequent arrhythmias
• External loop recorders should be considered in patients with a
symptom interval of less than 4 weeks
• Implantable loop recorders should be considered for most people
with syncope who have symptoms less than once a month and more
than once every three years
Up to 1/3 of Patients with Strokes of Unknown Cause may Have Atrial Fibrillation
Pause noted at 0630 – Diagnosis?
Crystal AF
Sanna et al N Engl J Med 2014; 370:2478-2486June 26,
2014
Echocardiogram
-Screening tool to rule out cardiac disease
-Low yield
-Mitral valve prolapse is the most frequent coincidental finding
Tilt table testing
• Pathophysiology
• The autonomic reflex: -arterial and cardiopulmonary
mechanoreceptors –brain stem –vagus & the sympathetic efferent
neurons
• Protocols
• Isoproterenol vs. NTG (94% specificity)
When to Perform an EP Study
• Patients with ischemic heart disease
• Patients with myocardial scar
• Bifasicular block
• Palpitations preceding syncope
• Other situations where value is unclear – Brugada syndrome,
hypertrophic cardiomyopathy, undiagnosed syncope
Patient with Syncope and Bifasicular block on EKG
Patient with Syncope Associated with Palpitations
A1H1
A1H1
A1H1
A1H1
AH Jump
Treatment Options
Bradycardia
Pacemaker
Ventricular
Arrhythmia
ICD
Neurocardiogenic
Syncope
Lifestyle
modification
Midodrine
Fludrocortisone
Medications
Beta Blockers
Pyridostigmine
Pacemaker
Support Stockings
The End
www.bostonscientific.com/cardiac-rhythm-resources/cameron-health/sicd-system.html
Questions
• 1 – What is the highest yield diagnostic maneuver for syncope?
• 2 – What are two the most important test for ruling out a life
threatening cause of cardiogenic syncope?
• 3 – What is the most important factor when choosing a heart
monitor?
Questions - Answers
• 1 – What is the highest yield diagnostic maneuver for syncope?
• History and Physical Exam
• 2 – What are two the most important test for ruling out a life
threatening cause of cardiogenic syncope?
• EKG and Echocardiogram
• 3 – What is the most important factor when choosing a heart
monitor?
• Frequency of Symptoms
European Heart Journal (2009) 30, 2631–2671;
doi:10.1093/eurheartj/ehp298
Treatment
• Neurocardiogenic/ vasovagal syncope
• Carotid sinus syndrome
• Situational syncope
• Orthostatic hypotension
Tilt Training
• Treatment of malignant and recurrent
vasovagal syncope
• 42 tilt-positive patients performed home tilt training:
two, 30-minute sessions daily
• After follow-up of 15.1±7.8 mos:
• 36 syncope free; 4 “presyncope”; 1 recurrence
• Conclusion: The abnormal autonomic reflex activity
of vasovagal syncope can be remedied
Reybrouck T, et al. PACE. 2000;23:493-498.
Prevention Of Syncope Trial (POST)
• Hypothesis: metoprolol will increase the time to
the first syncope recurrence
• Double-blind, randomized, placebo-control trial, powered
to detect 50% relative risk reduction of recurrent syncope
• Inclusion: >3 vasovagal spells, +TTT, age >18
• 208 patients; 38% completed follow-up without syncope
• Metoprolol ineffective overall. Age <42 did worse and
age >42 improved*
• Conclusion - metoprolol first line drug therapy for
age >42
*p=0.026 interaction with age
Sheldon R. HRS, San Fran. 2004.
Midodrine - Vasovagal Syncope
100
Symptom – Free Interval
80
60
Midodrine
Fluid
40
20
p < 0.001
0
0
20
40
60
80
100
Months
Perez-Lugones A, et al. JCE. 2001;12:935-938.
120
140
160
180
Pacemakers for Syncope
VPS I (North American Vasovagal Pacemaker Study)
• Objective: to evaluate pacemaker (PM) therapy
for severe recurrent vasovagal syncope
• Randomized, prospective, single center
• N=54 Patients
• 27—DDD pacemaker with rate drop response
• 27—no pacemaker
• Inclusion: vasodepressor response
• Primary outcome: first recurrence of syncope
Connolly SJ. J Am Coll Cardiol. 1999;33:16-20.
VPS I (North American Vasovagal Pacemaker
Study)
100
90
Cumulative Risk (%)
80
No Pacemaker (PM)
70
60
2P=0.000022
50
40
30
Pacemaker
20
10
Inclusion: vasodepressor response
0
0
3
6
9
Time in Months
12
15
Results: 6 (22%) with PM had recurrence vs. 19 (70%) without PM
84% RRR (2p=0.000022)
Connolly SJ. J Am Coll Cardiol. 1999;33:16-20.
VAsovagal Syncope International Study
(VASIS)
Pacemaker
100
% syncope-free
80
p=0.0004
60
40
No Pacemaker
20
Inclusion: cardioinhibitory response
0
2
3
4
5
6
Years
Results: 1 (5%) with PM had recurrence vs. 14 (61%) without PM.
Sutton R. Circulation. 2000;102:294-299.
VPS II (Vasovagal Pacemaker Study II)
• Objective: to determine if pacing therapy reduces the
risk of syncope in patients with vasovagal syncope
• Randomized, double-blind, prospective, multi-center
• N=100 patients:
• 52—only sensing without pacing
• 48—DDD pacemaker with rate drop response
• Inclusion: positive TTT with (HRXBP) < 6000/min X mm Hg
• Primary outcome: first recurrence of syncope
Connolly S. JAMA. 2003;289:2224-2229.
VPS II (Vasovagal Pacemaker Study II)
Role of Pacing
1.0
Cumulative Risk
0.8
0.6
Only Sensing Without
Pacing (ODO)
0.4
Dual Chamber Pacing
(DDD)
0.2
0
0
1
2
3
4
5
6
Months Since Randomization
Results: 33% with pacing had recurrence vs. 42% with only sensing (p=NS)
Connolly S. JAMA. 2003;289:2224–2229.