SADS 101
Peter Aziz MD, FHRS Director, Inherited Arrhythmia Clinic
Cleveland Clinic Children’s
No Disclosures
The Channelopathy Timeline
• 1889 – 1st recorded channelopathic death - J-LN • 1960s – Romano and Ward describe LQTS • 1986 – 1st BrS patient identified • 1991 – Keating identifies LQTS genetic location • 2000 – SQTS identified • 1995-present – Genetic data translated to
bedside
The Conduction System
The Ion Orchestra
Case Presentation 21yo soccer player with syncope
QTc = 540ms
Long QT Syndrome
• Leading cause of autopsy-negative sudden death - 1000/year in the US - Mostly young children
• Hallmark presentation: - Syncope – NO prodrome
• Hallmark arrhythmia:
Long QT Syndrome
Defective Ion Channels Causes QT Prolongation
K+ K+
Q Q T T
-80mV
+40mV
Epidemiology of LQTS
• Equally present in all races and ethnic groups
•
Estimated Prevalence of LQTS
• Prevalence among white patients - 17/43,080 = 1:2534
• Most common and most studied ion channelopathy - Natural history - Treatment - Genotype:phenotype correlation - Risk stratification
Schwartz, Circulation 2009
Long QT Classification
• 16 genotypes have been identified • Three are the most common forms:
- LQT1 - LQT2 - LQT3
• Remaining genotypes account for 5% • 20% remain genetically elusive
75% of LQTS
Cornerstones of Therapy Trigger Modification
Schwartz, JACC 2013
Trigger Avoidance
• LQT1
Trigger Avoidance
• LQT2
Trigger Avoidance
• LQT3
Cornerstone of Therapy
Case Presentation #2
• 14yo with multiple syncopal events - First occurred at age 6 while chasing
the ice cream truck
• Exercise Stress Test
Cathecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
• SCD in the setting of emotional or physical stress - Smells like long QT, but the ECG is normal
• Exercise stress test is the key - Frequent extra ventricular beats (PVCs)
• 30% will have at least 1 cardiac arrest • 80% will have at least 1 syncopal event • Estimated prevalence
- 1:10000
Cathecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Gene Protein Proportion of CPVT (%)
Inheritance Pattern
RYR2 Ryanodine 50-55 AD
CASQ2 Calsequestrin 2-5 AR
CALM1 Calmodulin <1 AD
TRDN Triadin Unknown AR
Cathecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Cathecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Treatment
± Flecainide ±
Case #4 10yo with Syncope at Rest
Brugada Syndrome
Brugada Syndrome
Treatment of Brugada Syndrome
• Patients at risk - Prior syncope - Those with BrS pattern at rest Internal Cardioverter Defibrillator (ICD)
SADS 101 Summary
Questions?