A Practical Approach to Syncope

A Practical Approach to SyncopeDr. Rohan GunawardenaConsultant Cardiac ElectrophysiologistNational Hospital of Sri Lanka

Definition• Transient loss of consciousness due to a globalreduction in cerebral blood flow.– Rapid onset– Very short duration– Loss of postural tone– Spontaneous and complete recovery

Exclusions• Conditions with LOC but no global cerebralhypoperfusion– Epilepsy– Hypoglycaemia, hypoxia, hyperventilation withhypercapnia– Intoxication– Vertibrobasilar TIA• Other disorders that mimic LOC– Cataplexy– Drop attacks, falls– Carotid circulation TIAs– psycogenic

Causes of true syncope• Neuro-cardiogenic (Reflex) syncope– Vasovagal– Situational– Carotid sinus– Atypical form• Orthostatic (hypotensive)– Iry autonomic failure– IIry autonomic failure– Drug induced– Volume depletionDue to impaired sympathetic efferent activityDue to inappropiate function of reflexes thatand/or reduced venous returnmaintain BP in the upright posture leading to• Iry Cardiac ANF – multiple system atrophy, purehypotension (vasodeppressor) or bradycardiaautonomic • Bradyarrhythmias failure, Lewy – SSS body or CHB dementia, ass.(cardioinhibitory)with •Tachy Parkinsons arrythmias – VT, SVT with LVVasovagal – prolonged standing/sitting,• IIry dysfunction, ANF – DM, AVNRT, amyloidosis, WPW ureamiaemotion, pain, blood.• Drug • Structural induced abnormalities – vasodilators, – AS, diuretics, MS, HOCM,Situational – cough, micturition, GI– Postural orthostatic tachycardia syndrome phenothiazines, Ischaemic/Dilated (POTS) antidepressantsCardiomyopathiesstimulation, laughing• Volume depletion – diorrhoea, vomitingCarotid sinus – hypersensitivity• POTS - ?inadequate venous return, excessiveAtypical – uncertain, absent triggersblood pooling• Cardiac– Brady-arrhythmias– Tachy-arrhythmias– Structural abnormalitiesNeurocardiogenicOrthostaticsyncope

Pre-syncope ↔ Syncope?

Tools in evaluating Syncope• History• HistoryHISTORY• History• Examination• Investigations• Is it true syncope• Is there a clue to theaetiology• Is there evidence ofhigh risk

Hx of syncope episodeLatest episode• Time of episode• Posture and Situation• Pre-syncope symptoms• Syncope description• RecoveryPrevious episodes

Case Hx 112 yr old girlEpisode of fainting in the morning duringassembly at school. She had started sweating,vision became blurred and friends said shebecame pale. Had collapsed onto the floor butrecovered immediately. Perfectly normal afterrecovery. Two previous episodes, once in Sundayschool while taking ‘pan sil’ and the other on theway back from school standing in a crowded bus.

• Time of episode– Early morning• VVS– Relationship with diet• DM– Medications• Anti-HT• Diabetic– Psychogenic– At night• Arrhythmias

Posture and situation– Sitting/standing at rest• Vasovagal– Supine• Arrhythmic• Epilepsy– During activity• Arrhythmic• Structural heart dis.

Posture and situation cont.• Emotional stress, fear, blood.– VVS• After exercise– Some arrhythmias (VT, SVT)• Warm, crowded places– VVS• Sudden change in posture– Autonomic failure– Carotid sinus syncope

• Case Hx 2• 62 yr old man• Rx in ICU for renal impairment andpneumonia• Short episode of syncope withdocumented asystole• R Carotid massage at bedside showedlong sinus pause

Preceding symptoms• Palpitations– VT, SVT• Headache, pallor, blurring of vision– VVS• Aura, lip smacking– epilepsy

Case Hx 3• 73 yr old woman• Repeated episodes of syncope lasting upto I minute• Preceded by palpitations• Holter runs of AF followed by long sinuspauses• EP study showed SSS

During syncope• Tonic clonic movements– epilepsy• Floppy– VVS• Tongue biting– Epilepsy• Incontinence– epilepsy• Injury– Risk assessment• Duration

Case Hx 4• 56 yr old man• Syncope during meeting• Lasted until reaching hospital – 20 minutes

Recovery• Spontaneous and complete– Reflex syncopes– Arrhythmias• Sleepy, loss of memory– Epilepsy

• AgeOther (relevant) Hx

VVSStructural HDAutonomic failureDrug inducedBrady-arrhythmias

Other (relevant) Hx• Age• Chest pain• Diabetes, IHD• Anti-hypertensives, anti psychotic• Impotence• Family Hx of SCA/SCD

Case Hx 5Episode of Syncopeyoung• 32 yr old female executive• On a flight back from UK (UL), one hour beforelanding• Not got up from seat.• Not eaten much or drunk water• Several glasses of wine during flight• On Nicardia for hypertension• Highly positive Tilt testlongperiodofsittingVasodilatationDehydration

Examination• Cardiac murmurs• CNS exam• Carotid sinus massage• Orthostatic BP measuring• Injuries

After Hx & ExDefinite Syncope• Very sure of cause• Have certain pointers• Have no idea at allNot True SyncopeTreat/referappropriatelyECG2D Echo

InvestigationsECG• bradycardia/conduction defects• WPW• evidence of IHD• VEs• Brugada synd/LQT/SQT

InvestigationsEchocardiogram• AS/MS• HCM• DCM

InvestigationsTrue syncopeAppropriate RxAppropriate IxsECGEchoReflex syncope orOrthostaticHypotension

InvestigationsTruesyncopeAppropriate RxAppropriate IxsECGEchoReflexsyncope/orthostatichypotensionHUTT/ActivestandingRx appropriately

Ix for Reflex SyncopeHead up tilt test (HUTT)• Tilting to a semi-erect position (70 0 ) after a period ofsupine rest.• Carotid sinus massage done while tilted• Blood pooling and ↓ venous return caused byorthostatic stress• Leads to sympathetic withdrawal and vagal overactivity• Causing hypotension and bradycardia• Sensitivity 70% and specificity 90%• Classically positive in VVS and in other reflex syncopes• Can also be positive in SSS

Carotid massage

Ix for Orthostatic HypotensionActive standing• Supine BP and frequent BP measurements upto 3 min – 30 min• Positive if fall in syst. BP >20mmHg or diast.>10mmHg or Syst.

InvestigationsTruesyncopeAppropriate RxAppropriate IxsECGEchoHUTT/ActivestandingReflexsyncope/orthostatichypotensionRx appropriately? arrhythmia1. Holter/loop recorder2. Ex ECG3. EP study

Ix for suspected arrhythmia• 24hr/48hr Holter– Frequent episodes• Loop recorders (external)– Less frequent symptoms• Implantable loop recorders– Gold standard Ix• Exercise ECG– Exercise induced syncope• EP study– Suspicion of a brady arrhythmia – Brady study– Evaluation of syncope in Cardiomyopathies/Brugada –VT stim

Bradycardiastudy

InvestigationsTruesyncopeAppropriateRxAppropriateIxsECGEchoReflexsyncope/orthostatichypotension1. Holter/looprecorder2. Ex ECG3. EP study? arrhythmiaHUTT/ActivestandingRxappropriatelyUncertainCertain diganosisRx

InvestigationsTruesyncopeAppropriateRxAppropriateIxsECGEchoReflexsyncope/orthostatichypotensionUncertain1. Holter/looprecorder2. Ex ECG3. EP study? arrhythmiaHUTT/ActivestandingRxappropriatelyUncertainCertain diganosisRx

UncertaindiagnosisHigh riskLow risk – 1-2 episodesLow risk -frequentEarly Ix/RxNo further IxRe-analyse HxTargeted IxsImplantable loop recorder

High Risk Patients who may need admissionand early electrophysiological evaluationThose with possible tachy-arrhythmias• Syncope during exertion or supine• Palpitations during syncope• Frequent VEs or NSVT• Pre-excited QRS complexes• Short or long QT intervals, Brugada pattern ECG• Family Hx of SCDThose with possible brady-arrhythmias• PR prolongation, Bi fascicular block, Intraventricular conduction defects(QRS>120ms)• Sinus bradycardia (< 50bpm) or sinoatrial blockEvidence of Coronary artery Dis, or Severe sructural Ht. Dis.• Hx of MI, Angina• Clinical evidence of Ht. failure or low EF on echo

Take home messages• History is the most important tool indiagnosing the aetiology of syncope(diagnoses up to 50%)• Targeted investigations are helpful inconfirming a diagnosis• Those patients at high risk need early Ix andRx

Case Hx 6• 68 year old women• Hx of syncope on 4 occasions during the last 3years• Gamut of Ix including EEG, CT, MRI• Admitted for in ward monitoring• Monitor showed CHB escape rhythm of