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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

1
• VVS
• CSS
• Situational
Cough
PostMicturition

2
• Drug-Induced
• ANS Failure
Primary
Secondary

Cardiac
Cardiac
Arrhythmia
Arrhythmia
3

• 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
4
• 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.


Impact of Syncope


40% will experience syncope
at least once in a lifetime1



1-6% of hospital admissions2



1% of emergency room visits
per year3,4



10% of falls by elderly are due
to syncope5



Major morbidity reported in 6%1
eg, fractures, motor vehicle accidents



Minor injury in 29%1
eg, lacerations, bruises

Kenny RA, Kapoor WN. In: Benditt D, et al. eds. The Evaluation and
Treatment of Syncope. Futura;2003:23-27.
2
Kapoor W. Medicine. 1990;69:160-175.
1

Brignole M, et al. Europace. 2003;5:293-298.
Blanc J-J, et al. Eur Heart J. 2002;23:815-820.
5
Campbell A, et al. Age and Ageing. 1981;10:264-270.
3
4


Impact of Syncope: US Trends
Inpatient Trend*
(000s)

Physician Office Visits**
(000s)

*All patients discharged with syncope and collapse
(ICD-9 Code:780.2) listed among diagnoses.
NHDS 2003.

**Syncope and collapse (ICD-9 Code: 780.2)

listed as primary reason for visit.
NAMCS 2002.


Impact of Syncope: US Trends

(000s)

Emergency
Department Visits*

(000s)

Hospital
Outpatient Visits*

+
*Syncope and collapse (ICD-9 Code:780.2) listed as
primary reason for visit.
NHAMCS 2002.

+ Not available


Impact of Syncope:
NHS Hospitals, England, 2002-2003*


74,813 hospital consults for
syncope and collapse



80% required hospital admission



Average length of stay: 6.1 days



327,201 hospital bed days,
second only to senility

*Hospital Episode Statistics, Dept. of Health, Eng. 2002-2003.


Impact of Syncope: Costs


Estimated hospital costs exceeded $10 billion US1



Estimated physician office expenses exceeded $470 million2



£104,285 spent on 1,334 patients with syncopal codes (UK)
(EaSyAS)3

• Hospital admission: 67% of investigational costs


Over $7 billion is spent annually in the US
to treat falls in older adults4

Kenny RA, Kapoor WN. In: Benditt D, et al. eds. The Evaluation and Treatment of Syncope. Futura;2003:23-27.
OutPatientView v. 6.0. Solucient LLC, Evanston IL.
3
Farwell D, et al. J Cardiovasc Electrophysiol. 2002;13(Supp):S9-S13.
4
Olshansky B. In: Grubb B and Olshansky B. eds. Syncope: Mechanisms and Management. Futura. 1998:15-71.
1
2


Impact of Syncope: Quality of Life

73%1
Percent of Patients

71%2
60%2
37%2

Anxiety/
Depression

Alter Daily

Activities

Restricted
Driving

Linzer M. J Clin Epidemiol. 1991;44:1037.
Linzer M. J Gen Int Med. 1994;9:181.

1
2

Change
Employment


Syncope Mortality


Low mortality vs.
high mortality



Neurally-mediated
syncope vs. syncope
with a cardiac cause

Soteriades ES, Evans JC, Larson MG, et al. Incidence and prognosis of syncope.
N Engl J Med. 2002;347(12):878-885. [Framingham Study Population]

Implications of Syncope for Driving a Vehicle
 Those

who drive and have
recurrent syncope risk their
lives and the lives of others

 Places

considerable burden
on the physician

 Essential

to know local laws
and physician
responsibilities

 Some

states – Invasion of
privacy to notify motor
vehicle department*

• Other states – Reporting
is mandatory*

Olshansky B, Grubb B. In: Syncope: Mechanisms and Management. Futura. Armonk, NY. 1998.
*Medtronic, Inc. Follow-up Forum. 1995/96;1(3):8-10.

Challenges of Syncope


Diagnosis

• Complex


Quality of life implications

• Work
• Mobility (automobiles)
• Psychological


Cost

• Cost/year
• Cost/diagnosis


Section II:
Diagnosis


Diagnostic Objectives


Distinguish true syncope from syncope mimics

• Syncope vs. dizziness, presyncope, drop attacks, vertigo, & seizures.
• Remember syncope can result in seizure-like activity.


Determine presence of heart disease

• Search for the presence of structural heart disease such as valvular
stenosis, cardiomyopathy, or myocardial infarction.

• This may suggest more malignant causes such as ventricular
tachycardia.

• Critical as most important factor in prognosis and risk stratification.


Establish the cause of syncope with
sufficient certainty to:

• Assess prognosis confidently
• Initiate effective preventive treatment


A Diagnostic Plan is Essential


Initial Examination

• Meticulous patient history

• Physical exam
• ECG
• Supine and upright

blood pressure
• Review patient’s Medication list






Monitoring
• Holter
• Event Recorder
• Insertable Loop Recorder (ILR)
Cardiac Imaging
• Echocardiogram
Special Investigations
• Head-up tilt test
• Hemodynamics
• Electrophysiology study (EPS)

Brignole M, et al. Europace, 2004;6:467-537.


Diagnostic Flow Diagram for TLOC
Initial Evaluation

Syncope

Certain
Diagnosis

Not Syncope

Suspected
Diagnosis

Unexplained
Syncope

Cardiac
Likely

Neurally-Mediated or
Orthostatic Likely

Frequent or Severe
Episodes

Single/Rare
Episodes

Cardiac
Tests

Tests for NeurallyMediated Syncope

Tests for NeurallyMediated Syncope

No Further
Evaluation

+

-

+

Re-Appraisal

Treatment

Treatment

Brignole M, et al. Europace, 2004;6:467-537.

+

Confirm with
Specific Test or
Specialist
Consultation

Re-Appraisal

Treatment

Treatment

Initial Exam: Detailed Patient History
Circumstances of recent event
• Eyewitness account of event
• Prodrome
• Symptoms at onset of event
• Sequelae
• Medications (proarrhythmic and QT prolonging agents)
 Circumstances of more remote events
 Concomitant disease, especially cardiac
 Pertinent family history
• Ask patient specifically about a positive family history of


unexpected sudden cardiac death
• Cardiac disease
• Metabolic disorders



Past medical history
• Neurological history
• Syncope
Brignole M, et al. Europace, 2004;6:467-537.


Initial Exam: Thorough Physical


Vital signs

• Heart rate
• Orthostatic blood pressure change


Cardiovascular exam: Is heart disease present?

• ECG: Long QT, pre-excitation, conduction system disease
• Echo: LV function, valve status (AS), HOCM


Neurological exam

• Abnormalities of cognition & speech, visual fields, motor strength,
sensation, tremor, and gait disturbance.



Carotid sinus massage

• Perform under clinically appropriate conditions preferably
during head-up tilt test

• Monitor both ECG and BP
Brignole M, et al. Europace, 2004;6:467-537.