Syncope
A Diagnostic and Treatment Strategy
Developed by:David G. Benditt, M.D. Richard Sutton, DScMedUniversity of Minnesota Medical Center Royal Brompton Hospital, London, UK
Presentation Overview
I. Prevalence & ImpactII. EtiologyIII. Diagnosis & Evaluation OptionsIV. Specific ConditionsV. Treatment OptionsVI. Insights into more efficient and effective
diagnosis and treatment of patients with syncope
Section I:
Prevalence and Impact
The Significance of Syncope
The only difference between
syncope and sudden death is that in one you wake up.1
1 Engel GL. Psychologic stress, vasodepressor syncope, and sudden death. Ann Intern Med 1978; 89: 403-412.
The Significance of Syncope
1 National Disease and Therapeutic Index on Syncope and Collapse, ICD-9-CM 780.2, IMS America, 19972 Blanc J-J, L’her C, Touiza A, et al. Eur Heart J, 2002; 23: 815-820.3 Day SC, et al, AM J of Med 19824 Kapoor W. Evaluation and outcome of patients with syncope. Medicine 1990;69:160-175
Individuals <18 yrs
Military Population 17- 46 yrs
Individuals 40-59 yrs*
Individuals >70 yrs*
15%
20-25%
16-19%
23%
Syncope Reported Frequency
*during a 10-year periodBrignole M, Alboni P, Benditt DG, et al. Eur Heart J, 2001; 22: 1256-1306.
The Significance of Syncope
500,000 new syncope patients each year 5
170,000 have recurrent syncope 6
70,000 have recurrent, infrequent, unexplained syncope 1-4
explained: 53% to 62%
infrequent, unexplained: 38% to 47% 1-4
1 Kapoor W, Med. 1990;69:160-175.2 Silverstein M, et al. JAMA. 1982;248:1185-1189.3 Martin G, et al. Ann Emerg. Med. 1984;12:499-504.
4 Kapoor W, et al. N Eng J Med. 1983;309:197-204.5 National Disease and Therapeutic Index, IMS America, Syncope and Collapse #780.2; Jan 1997-Dec 1997.6 Kapoor W, et al. Am J Med. 1987;83:700-708.
1 Day SC, et al. Am J of Med 1982;73:15-23.2 Kapoor W. Medicine 1990;69:160-175.3 Silverstein M, Sager D, Mulley A. JAMA. 1982;248:1185-1189.4 Martin G, Adams S, Martin H. Ann Emerg Med. 1984;13:499-504.
Some causes of syncope are potentially fatal Cardiac causes of syncope have the highest mortality
rates
The Significance of Syncope
0%
5%
10%
15%
20%
25%
Sync
ope
Mor
talit
y
Overall Due to Cardiac Causes
Impact of Syncope
11Linzer, Linzer, J Clin EpidemiolJ Clin Epidemiol, 1991., 1991.22Linzer, Linzer, J Gen Int MedJ Gen Int Med, 1994., 1994.
0%
20%
40%
60%
80%
100%
Anxiety/Depression
Alter DailyActivities
RestrictedDriving
ChangeEmployment
73% 171% 2
60% 2
37% 2
Pro
porti
on o
f Pat
ient
s
Section II:
Etiology
Syncope: A Symptom…Not a Diagnosis
Self-limited loss of consciousness and postural tone
Relatively rapid onset Variable warning symptoms Spontaneous complete recovery
Cause Prevalence (Mean) %
Prevalence (Range) %
Reflex-mediated:Vasovagal 18 8-37Situational 5 1-8
Carotid Sinus 1 0-4
Orthostatic hypotension 8 4-10
Medications 3 1-7
Psychiatric 2 1-7
Neurological 10 3-32
Organic Heart Disease 4 1-8
Cardiac Arrhythmias 14 4-38
Unknown 34 13-41
Causes of Syncope1
1Kapoor W. In Grubb B, Olshansky B (eds) Syncope: Mechanisms and Management. Armonk NY; Futura Publishing Co, Inc: 1998; 1-13.
Syncope: Etiology
Orthostatic CardiacArrhythmia
StructuralCardio-
Pulmonary
*
1• Vasovagal• Carotid
Sinus• Situational
CoughPost- micturition
2• Drug Induced• ANS
FailurePrimarySecondary
3• Brady
Sick sinusAV block
• TachyVTSVT
• Long QT Syndrome
4 • Aortic
Stenosis• HOCM• PulmonaryHypertension
5• Psychogenic• Metabolic
e.g. hyper-ventilation
• Neurological
Non-Cardio-
vascularNeurally-Mediated
Unknown Cause = 34%
24% 11% 14% 4% 12%
DG Benditt, UM Cardiac Arrhythmia Center
Causes of Syncope-like States
Migraine* Acute hypoxemia* Hyperventilation* Somatization disorder (psychogenic syncope) Acute Intoxication (e.g., alcohol) Seizures Hypoglycemia Sleep disorders
* may cause ‘true’ syncope
Section III:
Diagnosis and Evaluation Options
Syncope Diagnostic Objectives
Distinguish ‘True’ Syncope from other ‘Loss of Consciousness’ spells:SeizuresPsychiatric disturbances
Establish the cause of syncope with sufficient certainty to:Assess prognosis confidentlyInitiate effective preventive treatment
Initial Evaluation(Clinic/Emergency Dept.)
Detailed history Physical examination 12-lead ECG Echocardiogram (as available)
Syncope Basic Diagnostic Steps
Detailed History & PhysicalDocument details of eventsAssess frequency, severityObtain careful family history
Heart disease present? Physical examECG: long QT, WPW, conduction system diseaseEcho: LV function, valve status, HOCM
Follow a diagnostic plan...
Conventional Diagnostic Methods/YieldTest/Procedure Yield
(based on mean time to diagnosis of 5.1 months7
History and Physical (including carotid sinus massage)
49-85% 1, 2
ECG 2-11% 2
Electrophysiology Study without SHD* 11% 3
Electrophysiology Study with SHD 49% 3
Tilt Table Test (without SHD) 11-87% 4, 5
Ambulatory ECG Monitors: Holter 2% 7
External Loop Recorder(2-3 weeks duration)
20% 7
Insertable Loop Recorder(up to 14 months duration)
65-88% 6, 7
Neurological †
(Head CT Scan, Carotid Doppler) 0-4% 4,5,8,9,10
* Structural Heart Disease† MRI not studied
1 Kapoor, et al N Eng J Med, 1983.2 Kapoor, Am J Med, 1991.3 Linzer, et al. Ann Int. Med, 1997.4 Kapoor, Medicine, 1990.
5 Kapoor, JAMA, 19926 Krahn, Circulation, 19957 Krahn, Cardiology Clinics, 1997.8 Eagle K,, et al. The Yale J Biol and Medicine. 1983; 56: 1-8.
9 Day S, et al. Am J Med. 1982; 73: 15-23.10 Stetson P, et al. PACE. 1999; 22 (part II): 782.
Syncope Evaluation and Differential Diagnosis
Complete DescriptionFrom patient and observers
Type of Onset Duration of Attacks Posture Associated Symptoms Sequelae
History – What to Look for
12-Lead ECG
Normal or Abnormal?Acute MISevere Sinus Bradycardia/pauseAV BlockTachyarrhythmia (SVT, VT)Preexcitation (WPW), Long QT, Brugada
Short sampling window (approx. 12 sec)
Carotid Sinus Massage
Site: Carotid arterial pulse just below thyroid cartilage
Method:Right followed by left, pause betweenMassage, NOT occlusionDuration: 5-10 secPosture – supine & erect
Carotid Sinus Massage
Outcome: 3 sec asystole and/or 50 mmHg fall in systolic blood
pressure with reproduction of symptoms =
Carotid Sinus Syndrome (CSS) Contraindications
Carotid bruit, known significant carotid arterial disease, previous CVA, MI last 3 months
Risks1 in 5000 massages complicated by TIA
Conventional AECG
Low Yield, Poor Symptom / Arrhythmia Concordance*
8 studies, 2612 patients19% pts had symptoms with AECG
Only 4% had arrhythmia with symptoms
79% pts were without symptoms14% had arrhythmia despite absence of
symptoms
* ACC/AHA Task Force, JACC 1999;912-948
Method CommentsHolter (24-48 hours) Useful for infrequent events
Event Recorder Useful for infrequent eventsLimited value in sudden LOC
Loop Recorder Useful for infrequent eventsImplantable type more convenient (ILR)
Wireless (internet) Event Monitoring
In development
Ambulatory ECG
Head-up Tilt Test (HUT)
Unmasks VVS susceptibility
Reproduces symptoms Patient learns VVS
warning symptoms Physician is better able
to give prognostic / treatment advice
Head-Up Tilt Test (HUT)
DG Benditt, UM Cardiac Arrhythmia Center
Electroencephalogram
Not a first line of testingSyncope from SeizuresAbnormal in the interval
between two attacks – EpilepsyNormal – Syncope
Value of Event
Recorder in
Syncope
Linzer M. Am J Cardiol. 1990;66:214-219.
*Asterisk denotes event marker
Patient Activator Reveal® Plus ILR 9790 Programmer
Reveal® Plus Insertable Loop Recorder
ILR Recordings*56 yo woman with syncope accompanied with seizures.Infra-Hisian AV Block: Dual chamber pacemaker
65 yo man with syncope accompanied with brief retrograde amnesia.VT and VF: ICD and meds
*Medtronic data on file
Randomized Assessment of Syncope Trial
Usual care including:External loop recorderTilt test, EPS and others
Unexplained Syncopeafter history, physical exam, ECG, Holter
Low Risk (EF > 35%)
ILR
Diagnosis
+
+ --
ILR
External loop recorderTilt test, EPS, others
Krahn A, Klein GJ, Skanes Y. Circulation 2001; 104:46-51.
RAST Methods Prospective randomized trial
60 patients with unexplained syncope referred for cardiac investigation
Inclusion:Recurrent unexplained syncopeReferred to the arrhythmia service for cardiac investigationNo clinical diagnosis after history, physical, ECG and at least 24
hours of cardiac monitoring
Exclusion:LVEF < 35%Unable to give informed consentMajor morbidity precluding one year of follow-up
Krahn A, Klein GJ, Skanes Y. Circulation 2001; 104:46-51.
RAST Results
Unexplained Syncope
n=60
ILR
n=30
Conventional
n=30
In Follow-up
n=3
Diagnosed
n=14
Undiagnosed
n=13
Diagnosed
n=6
Undiagnosed
n=24
Krahn A, Klein GJ, Skanes Y. Circulation 2001; 104:46-51.
RAST Crossover Results
Krahn A, Klein GJ, Skanes Y. Circulation 2001; 104:46-51.
Unexplained Syncope
n=60
13/30
Undiagnosed after monitoring
6 accepted crossover to conventional
24/30
Undiagnosed after conventional
21 accepted crossover to ILR
Diagnosed
n=1
Undiagnosed
n=5
Diagnosed
n=8Undiagnosed
n=5
In follow-up
n=8
RAST - Diagnoses
0
2
4
6
8
10
12
14
Bradycardia Tachycardia Vasovagal Seizures
ILR Conventional
num
ber o
f pat
ient
s
Krahn A, Klein GJ, Skanes Y. Circulation 2001; 104:46-51.
Conventional EP Testing in Syncope
Limited utility in syncope evaluation
Most useful in patients with structural heart diseaseHeart disease……..50-80%No Heart disease…18-50%
Relatively ineffective for assessing bradyarrhythmias
Brignole M, Alboni P, Benditt DG, et al. Eur Heart Journal 2001; 22: 1256-1306.
EP Testing in Syncope:Useful Diagnostic Observations
Inducible monomorphic VT SNRT > 3000 ms or CSRT > 600 ms Inducible SVT with hypotension HV interval ≥ 100 ms (especially in
absence of inducible VT) Pacing induced infra-nodal block
Objectives:• Understand the mechanism of syncope in tilt-positive and tilt-
negative (isolated) patients
• Use the ILR to assess the correlation of rhythms captured during tilt testing and spontaneous recurrent episodes
Inclusion Criteria:• Patients with three or more syncopal episodes in the last 2
years
• Groups matched in age, sex, history of syncope, ECG, Echo abnormalities, SHD and arrhythmias
ISSUE StudyInternational Study of Syncope of Uncertain Etiology
Moya A. Circulation. 2001; 104:1261-1267
ISSUE Study Design
Multicenter, prospective
111 syncope patients3 episodes in 2 years, first and last episode >6 months apart
History, physical exam, ECG, CSM, echo, Holter (24 hr), other tests as appropriate
Tilt test followed by implant of Reveal Insertable Loop Recorder
Follow-up to recurrent spontaneous episodeMoya A. Circulation. 2001; 104:1261-1267
ISSUE Study Results
Results
Tilt-Negative Syncope (Isolated)
n=82
Tilt-Positive Syncope
n=29
Recurrent Event Occurrence (#) 34% (28) 34% (10)
Mean Time to Recurrent Event
(range)
105 days (47-226) 59 (22-98)
ILR ECG Documented (#) 29% (24) 28% (8)Tachyarrhythmia 2% (2)Bradycardia 16% (13) 21% (6)
–Sinus Brady 2% (2) 3% (1)–Sinus Arrest 12% (10) 17% (5)–AV Block 1% (1)
Total Arrhythmic 18% (15) 21% (6)
Normal Sinus Rhythm 11% (9) 7% (2)
Moya A. Circulation. 2001; 104:1261-1267
ISSUE Study Conclusions:
• Homogeneous findings from tilt-negative and tilt-positive syncope patients were observed (clinical characteristics and outcomes). Most frequent finding was asystole secondary to progressive sinus bradycardia, suggesting a neuromediated origin
• In this study tilt-negative patients had as many arrhythmias (18%) as tilt-positive patients (21%)
• In tilt-positive patients the spontaneous episode ECG was more frequently asystolic than what was predicted by tilt test
Moya A. Circulation. 2001; 104:1261-1267
ISSUE Study Implications HUT outcome was not predictive of
vasodepressor vs. cardioinhibitory responseBradycardia is common in spontaneous VVS -
independent of HUT outcome
Bradycardia is more prevalent in spontaneous events vs. HUT induced VVS
• Clinical Implication: Consider a strategy of postponing treatment until a spontaneous episode can be documented
Moya A. Circulation. 2001; 104:1261-1267
Symptom-Rhythm Correlation
Auto Activation Point
Patient Activation Point
Diagnostic Limitations
Difficult to correlate spontaneous events and laboratory findings
Often must settle for an attributable cause
Unknowns remain 20-30% 1
1Kapoor W. In Grubb B, Olshansky B (eds) Syncope: Mechanisms and Management. Armonk NY; Futura Publishing Co, Inc: 1998; 1-13.
Unexplained Syncope DiagnosisHistory and Physical Exam
Surface ECG
Neurological Testing
• Head CT Scan• Carotid Doppler• MRI• Skull Films• Brain Scan• EEG
CV Syncope Workup
• Holter• ELR or ILR• Tilt Table• Echo
• EPS
Other CV Testing
• Angiogram• Exercise Test• SAECG
Psychological Evaluation
ENT Evaluation Endocrine Evaluation
Adapted from: W.Kapoor.An overview of the evaluation and management of syncope. From Grubb B, Olshansky B (eds) Syncope: Mechanisms and Management. Armonk, NY: Futura Publishing Co., Inc.1998.
Typical Cardiovascular Diagnostic Pathway
History and Physical, ECG
Syncope
KnownSHD
NoSHD
Echo
EPS
+
Treat
> 30 days; > 2 Events
Tilt ILR
Tilt Holter/ ELR
ILR
Tilt/ILR
< 30 days
-
Adapted from:Linzer M, et al. Annals of Int Med, 1997. 127:76-86.Syncope: Mechanisms and Management. Grubb B, Olshansky B (eds) Futura Publishing 1999Zimetbaum P, Josephson M. Annals of Int Med, 1999. 130:848-856.Krahn A et al. ACC Current Journal Review,1999. Jan/Feb:80-84.
Section IV:
Specific Conditions
Neurally-Mediated Reflex Syncope (NMS)
Vasovagal syncope (VVS) Carotid sinus syndrome (CSS) Situational syncope
post-micturitioncoughswallow defecationblood drawingetc.
NM Reflex Syncope: Pathophysiology
Multiple triggers Variable
contribution of vasodilatation and bradycardia
NMS – Basic Pathophysiology
CerebralCortex
VascularBed Bradycardia/
Hypotension
Baro-receptors
Heart
Feedback viaCarotid Baroreceptors
Other Mechanoreceptors
Parasympathetic (+)
sympathetic (+) ¯ Heart Rate¯ AV Conduction
_ Vasodilatation
Benditt DG, Lurie KG, Adler SW, et al. Pathophysiology of vasovagal syncope. In: Neurally mediated syncope: Pathophysiology, investigations and treatment. Blanc JJ, Benditt D, Sutton R. Bakken Research Center Series, v. 10. Armonk, NY: Futura, 1996
Neurally Mediated Physiologic Reflex Mechanism with two Components:
Cardioinhibitory ( HR )Vasodepressor ( BP )
Both components are usually present
Vasovagal Syncope (VVS):Clinical Pathophysiology
Prevalence of VVS
Prevalence is poorly known Various studies report 8% to 37% (mean 18%)
of cases of syncope (Linzer 1997)
In general: VVS patients younger than CSS patients Ages range from adolescence to elderly
(median 43 years) Pallor, nausea, sweating, palpitations are common Amnesia for warning symptoms in older patients
DG Benditt, UM Cardiac Arrhythmia Center
16.3sec
Continuous Tracing1 sec
Spontaneous VVS
Management Strategies for VVS
Optimal management strategies for VVS are a source of debate Patient education, reassurance, instruction Fluids, salt, diet Tilt Training Support hose
Drug therapies Pacing
Class II indication for VVS patients with positive HUT and cardioinhibitory or mixed reflex
VVS: Tilt-Training
ObjectivesEnhance Orthostatic ToleranceDiminish Excessive Autonomic Reflex
ActivityReduce Syncope Susceptibility /
Recurrences
Technique Prescribed Periods of Upright PostureProgressive Increased Duration
Carotid Sinus Syndrome (CSS)
Syncope clearly associated with carotid sinus stimulation is rare (≤1% of syncope)
CSS may be an important cause of unexplained syncope / falls in older individuals
Etiology of CSS
Sensory nerve endings in the carotid sinus walls respond to deformation
“Deafferentation” of neck muscles may contribute
Increased afferent signals to brain stem
Reflex increase in efferent vagal activity and diminution of sympathetic tone results in bradycardia and vasodilation
Carotid Sinus
Carotid Sinus Hypersensitivity(CSH)
Abnormal response to CSM Absence of symptoms attributable to CSS CSH reported frequent in ‘fallers’ (Kenny)
CSH CSS
CSS and Falls in the Elderly
30% of people >65 yrs of age fall each year1
Total is 9,000,000 people in USAApproximately 10% of falls in elderly persons are due to
syncope2
50% of fallers have documented recurrence3
Prevalence of CSS among frequent and unexplained fallers unknown but…CSH present in 23% of >50 yrs fallers presenting at ER 3
1Falling in the Elderly: U.S. Prevalence Data. Journal of the American Geriatric Society, 1995.2 Campbell et al: Age and Aging 1981;10:264-270.3Richardson DA, Bexton RS, et al. Prevalence of cardioinhibitory carotid sinus hypersensitivity in patients 50 years or over presenting to the Accident and Emergency Department with “unexplained” or “recurrent” falls. PACE 1997
Section V:
Treatment Options
VVS: Pharmacologic Rx Salt /Volume
Salt tablets, ‘sport’ drinks, fludrocortisone
Beta-adrenergic blockers1 positive controlled trial (atenolol), 1 on-going RCT (POST)
Disopyramide SSRIs
1 controlled trial
Vasoconstrictors (e.g., midodrine)1 negative controlled trial (etilephrine)
Midodrine for Neurocardiogenic Syncope
Journal of Cardiovascular Electrophysiology Vol. 12, No. 8, Perez-Lugones, et al.
Months
p < 0.001Sym
ptom
– F
ree
Inte
rval
180160140120100806040200
100
80
60
40
20
0
FluidMidodrine
Status of Pacing in VVS
Perception of pacing for VVS changing: VVS with +HUT and cardioinhibitory response a Class IIb
indication1
Recent clinical studies demonstrated benefits of pacing in select VVS patients: VPS I VASIS SYDIT VPS II –Phase I ROME VVS Trial
1Gregoratos G, et al. ACC/AHA Guidelines for Implantation of Cardiac Pacemakers and Antiarrhythmic Devices. Circulation. 1998; 97: 1325-1335.
Status of Pacing in VVS
Benefits of specific device features evolving:Some success with DDD/DDI hysteresis 1
• “False positives” may result in prolonged high rate intervention• Tied to lower rate intervention
Rate drop therapies designed for treating VVS syncope appear to be successful 2-4
1 Sutton R, et al. Circulation. 2000; 102:294-299.2 Connolly S, et al. J Am Coll Cardiol 1999; 33:16-20.3 Ammirati F, et al. Circulation. 2002; 104: 52-57.4 Ammirati F, et al. NASPE Abstract #307. PACE, Vol. 24, April 2002, Part II.
VPS-IVasovagal Pacemaker Study I
Connolly S, et al. J Am Coll Cardiol 1999; 33: 16-20.
Study Design:54 patients randomized, prospective, single center
_ 27 DDD pacemaker with rate drop response (RDR)_ 27 no pacemaker
Patient Inclusion Criteria:6 syncopal events ever+HUTRelative bradycardia*
*a trough heart rate <60/min if no isoproterenol used, <70/min if up to 2 mcg/min isoproterenol used, or <80/min if over 2 mcg/min isoproterenol used
VPS- I
Connolly S, et al. J Am Coll Cardiol 1999; 33: 16-20.
Endpoints:Time to first syncope
Outcome:
RESULTS
PACEMAKER(n= 27)
CONTROL(n=27)
Number of patients w/syncopal recurrence 6 (22%) 19 (70%)
Mean time to first recurrence (days) 112 54
Relative risk reduction of syncope* 85.4% -*2p = 0.000022
VPS- I
Connolly S, et al. J Am Coll Cardiol 1999; 33: 16-20.
CumulativeRisk(%)
100
90
80
70
60
50
40
30
20
10
015129630
Control (No Pacemaker)
2P=0.000022
Pacemaker
Time in Months
NumberAt Risk
C 27 9 4 2 1 0P 27 21 17 12 11 8
VPS-I
Conclusion:Dual-chamber pacing with rate drop responsereduces the likelihood of syncope in patientswith recurrent VVS.
Connolly S, et al. J Am Coll Cardiol 1999; 33: 16-20.
VASIS Vasovagal Syncope International Study
Sutton, R, et al. Circulation. 2000; 102:294-299.
Study Design:42 patients, randomized, prospective, multicenter
_ 19 DDI pacemaker (80 bpm) with rate hysteresis (45 bpm)_ 23 no pacemaker
Patient Inclusion Criteria:> 3 syncopal events in 2 years and last event occurring within
6 months of enrollment and,Positive VASIS type 2A or 2B cardioinhibitory response to HUT
and,Age > 40 years or drug refractory if < 40 years
VASIS
Sutton, R, et al. Circulation. 2000; 102:294-299.
Outcome:
RESULTS Pacemaker(n= 19)
No Pacemaker
(n=23)
Number of patients w/syncopal recurrence 1 (5%) 14 (61%)
Median time to first recurrence (months)* 15 5
*P= 0.0006
Endpoints:Time to first syncope
VASIS
Pacemaker
No-Pacemaker
p=0.0004
Years
% s
ynco
pe-fr
ee
100
80
60
40
20
0 2 3 4 5 6
7121415233140# of pts
Sutton, R, et al. Circulation. 2000; 102:294-299.
VASIS
Conclusion:Dual-chamber pacing (at a rate of 80 bpm ) with rate hysteresis reduces the likelihood of syncope in patients with tilt-positive, cardioinhibitory syncope.
Sutton, R, et al. Circulation. 2000; 102:294-299.
SYDIT Syncope Diagnosis and Treatment Study
Study Design:93 patients randomized, prospective, multicenter
_ 46 DDD pacemaker with rate drop response (RDR)_ 47 Atenolol 100 MG/D
Patient Inclusion Criteria: > 55 yrs> 3 syncopal episodes in 2 years + HUT with relative bradycardia (trough HR <60 bpm)
Ammirati F, et al. Circulation. 2001; 104:52-57.
SYDIT
Endpoints: Time to first syncope
Outcome:
RESULTS
PACED(n= 46)
DRUG(n= 47)
Number of patients w/syncopal recurrence* 2 (4%) 12 (25%)
Median time to first recurrence (days) 390 135
*P=0.004
Ammirati, et al. Circulation. 2001; 104:52-57.
Syncope-free Survival: Intention-to-Treat (n=46/paced, 47/drug).
Ammirati F, et al. Circulation. 2001; 104:52-57.
SYDIT
1.0
Time (days)
100
0.9
0.8
0.7
0.6200 300 400 500 600 700 800 900 10000
P = 0.0032
drugpacemaker
% o
f syn
cope
free
pts
SYDIT
Conclusion:Dual-chamber pacing + RDR is superior to Atenolol in prevention of recurrent syncope in highly symptomatic patients with relative bradycardia during tilt-induced syncope.
Ammirati F, et al. Circulation. 2001; 104:52-57.
VPS-II: Phase IVasovagal Pacemaker Study-II
Study Design:100 patients, randomized, prospective, multicenter
_ 50 DDD pacemaker with rate drop response (RDR)_ 50 ODO pacemaker (inactive mode)
Patient Inclusion Criteria:> 6 syncope events ever or > 3 syncope events in
2 years or > 1 syncope event in 6 months and,Positive HUT with syncope or presyncope and a
heart rate blood pressure product <9000
Presented at the 23rd Annual Scientific Sessions of the North American Society of Pacing and Electrophysiology. Late Breaking Clinical Trials, May 11, 2002.
VPS-II: Phase I
Endpoints: Time to first syncope
Outcome:
RESULTS
DDD Pacemaker(n= 50)
ODO Pacemaker(n= 50)
Number of patients w/syncopal recurrence 16 (32%) 22 (44%)
Relative Risk Reduction* 28.7% -
*P=0.153
Presented at the 23rd Annual Scientific Sessions of the North American Society of Pacing and Electrophysiology. Late Breaking Clinical Trials, May 11, 2002.
0.4
0.3
0.2
ODODDD
P = 0.153 (one-sided)
Number at Risk ODO 40 37 35 32 31 21DDD 39 36 34 33 33 17
0 1 2 3 4 5 6
0.1
0.0
Cum
ulat
ive
Ris
k of
Sy
ncop
e
Presented at the 23rd Annual Scientific Sessions of the North American Society of Pacing and Electrophysiology. Late Breaking Clinical Trials, May 11, 2002.
VPS-II: Phase I
VPS-II: Phase I
Conclusions: Lower than anticipated syncope event rate in the
control arm. Higher than anticipated event rate in the treatment
group. Consequence: treatment effect was less than VPS-I. Results favored pacing but the treatment effect was
not statistically significant.
Presented at the 23rd Annual Scientific Sessions of the North American Society of Pacing and Electrophysiology. Late Breaking Clinical Trials, May 11, 2002.
VVS Pacing Trials Conclusions
DDD pacing reduces the risk of syncope
in patients with recurrent, refractory,
highly-symptomatic, cardioinhibitory
vasovagal syncope.
SAFE PACE Study Design
Randomized controlled trial (N=175): Pacing (87) vs. No Pacing (88)
Single center: Royal Victoria Infirmary, Newcastle, UK
Recruitment began: April 1998 12 month follow-up per patient Study concluded: May 2000
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
SAFE PACE Inclusion Criteria
Consecutive adults attending accident and emergency department• > 50 Years
- Experienced non-accidental fall
•Positive response to CSM
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
SAFE PACE Screening ProcessAccident and Emergency Attendees > 50 Yrs
Falls or Syncope
Non-accidental Fall
CSM Performed
Cardioinhibitory or Mixed CSH
RCT
Control Pacemaker
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
SAFE PACE Screening Results
RCT (n=175)
Control (n=88)
Pacemaker (n=87)
• No pacing intervention • Medtronic Thera DR(Rate Drop ResponseAlgorithm)
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
SAFE PACE ResultsNumber of Falls
Control
n=87
Pacemaker
n=84% Participants w/Falls
60% 58%
Total Number of Falls*
699 216
Mean Number of Falls**
9.3 4.1
* Falls during 12 months post randomization** Crude adjustment calculation
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
70%Reduction[OR 0.42; 95%CI: 0.23, 0.75]
Control
N=87
Pacemaker
N=84
% Participants w/Syncopal Events
22% 11%
Total Number of Syncopal Events
47 22
Mean Number Syncopal Events
1.14 0.20
SAFE PACE ResultsNumber of Syncopal Episodes
50%Reduction[OR 0.53; 95%
CI 0.23; 1.20 ns]
* Syncopal events 12 months past randomization** Crude adjustment calculation
Kenny RA, J Am Coll Cardiol 2001; 38:000-000.
Control
n= 87
Pacemaker
n= 84
% Participants w/Injurious Events
41% 35%
Total Number Injury Events
202 61
-Fractures
-Soft Tissue Injury
4
198
3
58
SAFE PACE ResultsNumber of Injury Events
70%Reduction
* Injurious events 12 months post randomization
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
SAFE PACE Conclusions
In patients with unexplained falls and a diagnosis of Cardioinhibitory CSH, cardiacpacing reduced the total number of:
Falls by 70% Syncopal events by 53% Injurious events by 70%
Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
Role of Pacing in CSS --Syncope Recurrence Rate
Brignole et. Al. Diagnosis, natural history and treatment. Eur JCPE. 1992; 4:247-254
0%
25%
50%
75%
No Pacing Pacing
57%
%6% R
ecur
renc
e
Class I indication for pacing (AHA and BPEG)Limit pacing to CSS that is:
•Cardioinhibitory•Mixed
DDD/DDI superior to VVI
(Mean follow-up = 6 months)
Section VI:
Insights into More Efficient and Effective Diagnosis and Treatment
Principal Causes of Orthostatic Syncope
Drug-induced (very common) diuretics vasodilators
Primary autonomic failure multiple system atrophy Parkinsonism
Secondary autonomic failure diabetes alcohol amyloid
Alcohol orthostatic intolerance apart from neuropathy
Syncope Due to Arrhythmia or Structural CV Disease:
General Rules
Often life-threatening and/or exposes patient to high risk of injury
May be warning of critical CV disease Aortic stenosis, Myocardial ischemia, Pulmonary
hypertension
Assess culprit arrhythmia / structural abnormality aggressively
Initiate treatment promptly
Principal Causes of Syncope due to Structural Cardiovascular Disease
Acute MI / IschemiaAcquired coronary artery disease Congenital coronary artery anomalies
HOCM Acute aortic dissection Pericardial disease / tamponade Pulmonary embolus / pulmonary
hypertension Valvular abnormalities
Aortic stenosis, Atrial myxoma
Syncope Due to Cardiac Arrhythmias
Bradyarrhythmias Sinus arrest, exit block High grade or acute complete AV block
Tachyarrhythmias Atrial fibrillation / flutter with rapid ventricular
rate (e.g. WPW syndrome) Paroxysmal SVT or VT Torsades de pointes
Rhythms During Recurrent Syncope
Krahn A, et al. Circulation. 1999; 99: 406-410
Normal Sinus Rhythm
58%Normal Sinus Rhythm
58%
Bradycardia
36%
Tachyarrhythmia
6%
AECG: 74 yr Male, Syncope
From the files of DG Benditt, UM Cardiac Arrhythmia Center
Syncope: Torsades
From the files of DG Benditt, UM Cardiac Arrhythmia Center
83 yo womanBradycardia: Pacemaker implanted
28 yo man in the ER multiple times after falls resulting in traumaVT: ablated and medicated
Reveal ® ILR recordings; Medtronic data on file.
Infra-His Block
From the files of DG Benditt, UM Cardiac Arrhythmia Center
Drug-Induced QT Prolongation Antiarrhythmics
Class IA ...Quinidine, Procainamide, DisopyramideClass III…Sotalol, Ibutilide, Dofetilide, Amiodarone, (NAPA)
Antianginal Agents (Bepridil)
Psychoactive AgentsPhenothiazines, Amitriptyline, Imipramine, Ziprasidone
AntibioticsErythromycin, Pentamidine, Fluconazole
Nonsedating antihistamines (Terfenadine), Astemizole
Others (Cisapride), Droperidol
Treatment of Syncope Due to Bradyarrhythmia
Class I indication for pacing using dual- chamber system wherever adequate atrial rhythm is available
Ventricular pacing in atrial fibrillation with slow ventricular response
Treatment of Syncope Due to Tachyarrhythmia
Atrial Tachyarrhythmias;AVRT due to accessory pathway – ablate pathwayAVNRT – ablate AV nodal slow pathwayAtrial fib– Pacing, linear / focal ablation, ICD selected ptsAtrial flutter – Ablation of reentrant circuit
Ventricular Tachyarrhythmias;Ventricular tachycardia – ICD or ablation where appropriateTorsades de Pointes – withdraw offending Rx or ICD (long-
QT/Brugada)
Drug therapy may be an alternative in many cases
Conclusion
Syncope is a common symptom, often with dramatic consequences,
which deserves thorough investigation and appropriate treatment of its cause.
DisclaimerINDICATIONS9526 Reveal® Plus Insertable Loop RecorderThe Reveal Plus Insertable Loop Recorder (ILR) is an implantable patient activated monitoring system that records subcutaneous ECG and is indicated for patients who experience transient symptoms that may suggest a cardiac arrhythmia. 9790 ProgrammerThe Medtronic 9790 Programmers are portable, microprocessor based instruments used to program Medtronic implantable devices. 6191 ActivatorThe Model 6191 Activator is intended for use in combination with a Medtronic Model 9525 Reveal ® and the Model 9526 Reveal Plus Insertable Loop Recorders. CONTRAINDICATIONSThere are no known contraindications for the implantation of the Reveal Plus ILR. However, the patient’s particular medical condition may dictate whether or not a subcutaneous, chronically implanted device can be tolerated. WARNINGS/PRECAUTIONS9526 Reveal Plus Insertable Loop RecorderPatients with the Reveal Plus ILR should avoid sources of magnetic resonance imaging, diathermy, high sources of radiation, electrosurgical cautery, external defibrillation, lithotripsy, and radiofrequency ablation to avoid electrical reset of the device, and/or inappropriate sensing. 6191 ActivatorOperation of the Model 6191 Activator near sources of electromagnetic interference, such as cellular phones, computer monitors, etc., may adversely affect the performance of this device. See the appropriate technical manual for detailed information regarding indications, contraindications, warnings, and precautions. Caution: Federal law (U.S.A.) restricts this device to sale by or on the order of a physician.
DisclaimerINDICATIONS
Medtronic.Kappa 700 Series Pacemakers
The Medtronic.Kappa 700 Series pacemakers are indicated for rate adaptive pacing in patients who may benefit from increased pacing rates concurrent with increases in activity and are also indicated for dual chamber and atrial tracking modes in patients who may benefit from maintenance of AV synchrony. Dual chamber modes are specifically indicated for treatment of conduction disorders that require restoration of both rate and AV synchrony, which include various degrees of AV block to maintain the atrial contribution to cardiac output and VVI intolerance (e.g., pacemaker syndrome) in the presence of persistent sinus rhythm.
9790 Programmer
The Medtronic 9790 Programmers are portable, microprocessor based instruments used to program Medtronic implantable devices.
9462
The Model 9462 Remote Assistant is intended for use in combination with a Medtronic implantable pacemaker with Remote Assistant diagnostic capabilities.
CONTRAINDICATIONS
The Medtronic.Kappa 700 Series pacemakers are contraindicated for the following applications:
· Dual chamber atrial pacing in patients with chronic refractory atrial tachyarrhythmias.
· Asynchronous pacing in the presence (or likelihood) of competitive paced and intrinsic rhythms.
· Unipolar pacing for patients with an implanted cardioverter-defibrillator (ICD) because it may cause unwanted delivery or inhibition of ICD therapy.
WARNINGS/PRECAUTIONS
Medtronic.Kappa 700 Series patients should avoid sources of magnetic resonance imaging, diathermy, high sources of radiation, electrosurgical cautery, external defibrillation, lithotripsy, and radiofrequency ablation to avoid electrical reset of the device, inappropriate sensing and/or therapy.
See the appropriate technical manual for detailed information regarding indications, contraindications, warnings, and precautions.
Caution: Federal law (U.S.A.) restricts this device to sale by or on the order of a physician.
Additional Slides
Falls -- Incidence, Recurrence, CHS*
1 Falling in the Elderly, 1995.2 Richardson, PACE, 1997.
0%
25%
50%
75%
Incidence> 65 yrs. old
Recurrence CSH* presentin fallers > 50 yrs.presenting at ER
30% 1
50% 1
23% 2
Per
cent
of P
eopl
e
* Carotid Sinus Hypersensitivity
VVS Pacing TrialsComparison Summary
Pacing in VVS
Two randomized, controlled trials suggest benefit in selected patients with multiple (>5 lifetime) syncope recurrences and one or more of: prominent cardioinhibitory featuresasystolic pause >10 secondssustained HR<40/minute
VVS Recurrences
35% of patients report syncope recurrence during follow-up ≤3 years
Positive HUT with >6 lifetime syncope episodes: recurrence risk >50% over 2 years
Sheldon et al. Circulation 1996; 93: 973-81.
Savage et al. STROKE 1985; 16: 626-29.
SAFE PACE 2: Syncope and Falls in the Elderly
30% of individuals >65 yrs fall each year 5% of falls result in fractures 1% of falls result in hip fractures SAFEPACE Pilot Study
18% prevalence of CSH in unexplained ‘fallers’
31% in ‘fallers’ >80 yrs Kenny RA, J Am Coll Cardiol 2001; 38:1491-1496.
Both
Rate Drop Response Overview
Detection Options
DropDetect
Low RateDetect
Detects relative heart rate drops
of a pre-determined size
Detects heart rate that falls to a user-defined
lower rate
Detection occurs when either Drop Detection or Low
Rate Detection criteria are met
Rate Drop Detection in Medtronic Kappa® Series Pacemakers
Drop Detection with Intervention
Drop Detection Method: Drop Size 25, Drop Rate 70
40
50
60
70
80
90
100
110
Ven
tricu
lar R
ate
Drop Size=25 bpm
Drop Rate
Peak Rate=90 bpm
2 consecutive beats < Drop Size and Drop Rate
Rate Drop Detection in Medtronic Kappa® Series Pacemakers
Drop Detect Peak Rate
Drop Detection Method: Drop Size 25
40
50
60
70
80
90
100
110
120
Ven
tricu
lar R
ate
Drop Size=25 bpm
Peak Rate=90 bpm
Rate Drop Detection in Medtronic Kappa® Series Pacemakers
Low Rate Detection Method: Lower Rate 40, Detection beats 2
30
40
50
60
70
80
90
100
110
Ven
tricu
lar R
ate
Lower Rate
2 consecutive paced beats at Lower Rate
Low Rate Detect
Rate Drop Detection in Medtronic Kappa® Series Pacemakers
Using Both Detection Algorithms
When both detection algorithms are used:Detection occurs when either Drop Detection
or Low Rate Detection criteria are metIntervention Rate, Duration and Termination
are programmed the same as when using the individual detection modes
Rate Drop Detection in Medtronic Kappa® Series Pacemakers
Rate Drop Intervention Therapy
DDD or DDI pacing Pacing intervention
Paces at programmed Intervention Rate for programmed duration
Pacing terminationPacing rate decreases until there are three
consecutive atrial senses or Lower Rate is reached
Rate Drop Detection in Medtronic Kappa® Series Pacemakers
Challenges of Syncope Cost
Cost/year Cost/diagnosis
Quality of Life Implications Work/financial Mobility (automobiles) Psychological
Diagnosis & Treatment Diagnostic yield and repeatability of tests Frequency and clustering of events Difficulty in managing/treating/controlling future events Appropriate risk stratification Complex Etiology
Diagnosing VVS
Patient history and physical exam Positive tilt table test
(ACC Consensus Protocol) Overnight fast ECG Blood pressure Supine and upright Tilt to 60-80 degrees Isoproterenol Re-tilt
DG Benditt, Tilt Table Testing, 1996.
60° - 80°
VVS: Treatment Overview Education
symptom recognition reassurancesituation avoidance
Tilt-Training prescribed upright posture
Pharmacologic Agentssalt/volume management beta-adrenergic blockersSSRIsvasoconstrictors (e.g., midodrine)
Cardiac Pacemakers
Tilt-Training: Clinical Outcomes
42 HUT positive (21±13 min) VVS patients Home training: two 30 minute sessions daily Outcomes
41/42 pts --->45 min asymptomatic HUT Clinical follow-up: 15.1±7.8 mos
• 36 pts syncope free• 4 pts: presyncope• 1 pt: syncope recurrences
Reybrouck et al. PACE 2000; 23:493-8
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