Syncope V12 2e

Chap 4

Syncope Jiaqi Zhao

Department of Cardiology, Affiliated Hospital of Ji ning Medical College, Ji ning

Outline       

Definition Epidemiology Why it’s important Possible causes Distribution of causes in community Clues to diagnosis Approach

Definition 

 

Abrupt and transient loss of consciousness Absence of postural tone Spontaneous rapid and full recovery

Incidence

Sorteriades ES, et al. NEJM. 2002

Epidemiology  



Actual rates likely higher 30% of young adults report prior episode of syncope 6% annual incidence in elderly

Why it’s Important 

 



1.



Alarming to patient, family and clinicians Injuries occur in ~35% of patients1 Accounts for 1% of hospital admissions and 3% of ER visits2 Annual evaluation and treatment cost of $800M in 19993 Recurrent episodes = poor QOL4

Olshansky B. Up to Date, updated April 2005

2.

Kapoor W. JAMA 1992

3.

Nyman JA, et al. Pacing Clin Electr 1999

4.

Linzer M, et al. J Clin Epid 1991

Broad Causes of Syncope       

Reflex mediated Orthostatic hypotension Cardiac dysrhythmia Cardiac Obstruction Neurologic Metabolic Unexplained

Reflex Mediated        

Neurocardiogenic (vasovagal) Carotid sinus hypersenstivity Micturition Cough Defecation Deglutition Postprandial Gelastic1 1. Braga SS et al. Lancet 2005

Orthostatic    

Medication related Fluid depletion Illness/bedrest Dysautonomias 





Bradbury Eggleston Syndrome (pure autonomic failure) Shy Drager Syndrome (multiple system atrophy) Parkinsonism with autonomic failure

Cardiac Dysrhythmia 

Bradycardias  



Sinus node disease AV and infranodal conduction system disease

Tachyarrhythmias   

SVT with accessory AV pathway VT with structural heart disease VT with no structural heart disease

Cardiac Obstruction   

  

Aortic stenosis Atrial myxoma Hypertrophic cardiomyopathy with obstruction Severe pulmonary hypertension Pulmonary embolism Cardiac tamponade

Metabolic   

Hypoglycemia Hypoxia Hyperventilation

Framingham Heart Study 40 35 30 25

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Soteriades ES et al. NEJM. 2002.

Prognosis

Sorteriades ES, et al. NEJM. 2002

Helpful Clues in History      



Age Context Pattern Prodrome Observations of witnesses Chronic Illnesses/known cardiac disease Medications

History, Physical and ECG

Clear cut reflex mediated or

Specific mechanism

Not a clue !!!

suspected

orthostatic

Treat

Dx specific testing

Exclude fatal causes

Strickberger SA et al. JACC 2006

Potentially Fatal Causes  

Silent ischemia/unrecognized CAD Structural heart disease   



Impaired systolic function (low EF) Hypertrophic cardiomyopathy Arrhythmogenic right ventricular dysplasia (ARVD)

Primary electrical disease   



Long QT syndrome Brugada syndrome Catecholaminergic polymorphic ventricular tachycardia Presence of an accessory pathway

Syncope in Known CAD Echo EF <35%

ICD

EF >35%

Cath +/- revascularization

EP Study unremarkabl e Observe/ILR

monomorphic VT ICD/ablate

Unstable SVT/AP Sinus node or conduction PPM dz

Ablate/PPM with AT Rx

Syncope in HCM   

Annual risk of SCD is 0.6 to 1% EP studies generally not useful Risk factors for sudden death     



Syncope !!! Family history of SCD Frequent NSVT Wall thickness > 30 mm Genotyping not ready for prime time

ICDs are effective

Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy



 

 

~20% of SCD in pts < 35 may be due to ARVD 30-50% are familial, others sporadic Present with PVCs, syncope, sustained VT with LBBB morphology Utility of EP testing not established With ICD rx, the annual rate of appropriate shocks is 15-20%

ARVD

Kies P et al. J Cardiovasc Electrophysiol; 17: 586-593. 2006

Long QT Syndrome

Brugada Syndrome