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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.


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