Sudden Cardiac Death in the Young Athlete

1. Sudden Cardiac Death in the Young Athlete KSNA Meeting March 14, 2011 Timothy K. Knilans, M.D.Director, Clinical Cardiac Electrophysiology and Pacing The Heart Institute

2. The Problem Cardiac Arrest • Rare in Children • 0.3-1/100,000 high school athletes • 25-50 children per year in US annually • 1/200th of the risk in adults >35 years-old

3. Basketball Star's Sudden Death Brings Awareness of Deadly Heart Disease By Dan O'Donnell The shockwaves from high school basketball star Wes Leonard's sudden death last week have reverberated from Fennville, Michigan across the nation. Leonard, 16, had just scored the winning layup in an overtime victory that clinched a perfect 20-0 season for his Fennville Blackhawks when he collapsed on the court, dying at a hospital a short time later. An autopsy revealed that Leonard suffered cardiac arrest brought on by dilated cardiomyopathy (DCM), a condition more commonly referred to as an "enlarged heart."

4. Why does it happen? • Underlying unrecognized problems • Underlying recognized problems • Sudden occurrence without preexisting problem

5. Undiagnosed Underlying Problems Cardiac muscle disease • Hypertrophic Cardiomyopathy (HCM) • Dilated Cardiomyopathy (DCM) • Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) • Left Ventricular Non-Compaction Cardiomyopathy (LVNC)

6. Undiagnosed Underlying Problems Hypertrophic Cardiomyopathy (HCM) • Heritable disorder with genetic basis • Asymmetric thickening of the left ventricle • Septum thicker than free-wall • May have associated symptoms • Chest pain • Dizziness • Syncope • First symptom may be cardiac arrest • Ventricular tachyarrhythmia

7. Undiagnosed Underlying Problems Hypertrophic Cardiomyopathy (HCM)

8. Undiagnosed Underlying Problems Hypertrophic Cardiomyopathy (HCM) • 0.2% prevalence in young adults • Higher incidence in males and blacks • Heart murmur • Abnormal electrocardiogram • Ventricular hypertrophy pattern • Abnormal echocardiogram • Asymmetric left ventricular hypertrophy • Genetic testing

9. Undiagnosed Underlying Problems Dilated Cardiomyopathy (DCM) • Weakening of ventricular contraction • Enlargement of left ventricle

10. Undiagnosed Underlying Problems Dilated Cardiomyopathy (DCM) • Symptoms • Exercise intolerance • Shortness of breath • Palpitations • Failure to thrive • Syncope

11. Undiagnosed Underlying Problems Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) • 1/10,000 in United States • Genetic mutations • Fatty and Fibro-fatty infiltration of right ventricle • Electrocardiographic abnormalities • Symptoms • Syncope • Cardiac arrest

12. Undiagnosed Underlying Problems Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

13. Undiagnosed Underlying Problems Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

14. Undiagnosed Underlying Problems Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) • Events rare in children • Use-dependent disease • Worsens with exertion and cardiac stress

15. Undiagnosed Underlying Problems Left Ventricular Non-Compaction Cardiomyopathy (LVNC) • Failure of myocardial development during embryogenesis • “Spongy” myocardium • Symptoms • Exercise intolerance • Fatigue • Dyspnea • Syncope

16. Undiagnosed Underlying Problems Left Ventricular Non-Compaction Cardiomyopathy (LVNC)

17. Undiagnosed Underlying Problems Cellular Cardiac Electrical Abnormality • Long QT Syndrome • Brugada Syndrome • Catecholaminergic Polymorphic Ventricular Tachycardia • Short QT Syndrome

18. Undiagnosed Underlying Problems Basis of Cardiac Electrical Activity • Sodium-potassium pump • Exchanges Sodium for Potassium at the cell wall • High intracellular Potassium concentration • Low intracellular Sodium concentration

19. Undiagnosed Underlying Problems Sodium-Potassium Gradient

20. Undiagnosed Underlying Problems Water Tower Analogy

21. Undiagnosed Underlying Problems Cardiac Ion Channels from: Royal Society of Chemistry, www.chemsoc.org

22. Undiagnosed Underlying Problems Pore Configuration from: Royal Society of Chemistry, www.chemsoc.org

23. Undiagnosed Underlying Problems Long QT Syndrome • Congenital usually with autosomal dominanat inheritance • Most commonly abnormal function of potassium or sodium channel • Prolongation of the QT interval is seen on the resting ECG

24. Undiagnosed Underlying Problems Long QT Syndrome

25. Undiagnosed Underlying Problems Long QT Syndrome

26. Undiagnosed Underlying Problems Brugada Syndrome • Genetic syndrome • Electrocardiographic abnormality • Associated with ventricular arrhythmia • Events are rare in children

27. Undiagnosed Underlying Problems Brugada Syndrome

28. Undiagnosed Underlying Problems Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) • Genetic syndrome • Calcium channel mutation • Ryanodine receptor abnormality • Ventricular arrhythmia associated with exercise

29. Undiagnosed Underlying Problems Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)

30. Undiagnosed Underlying Problems Short QT Syndrome • Genetic syndrome • Usually autosomal dominant inheritance • Potassium channel abnormality • Short QT interval on resting ECG

31. Undiagnosed Underlying Problems Short QT Syndrome

32. Undiagnosed Underlying Problems Macro-anatomic Cardiac Electrical Disease • Wolff-Parkinson-White syndrome • AV block

33. Undiagnosed Underlying Problems Wolff-Parkinson-White syndrome • Usual sporadic occurrence • 0.1-0.3 % incidence • Abnormal resting ECG • Associated supraventricular tachycardia • Not life-threatening • Rapid conduction during atrial fibrillation • May be life-threatening

34. Undiagnosed Underlying Problems Wolff-Parkinson-White syndrome

35. Undiagnosed Underlying Problems Wolff-Parkinson-White syndrome

36. Undiagnosed Underlying Problems AV block • Congenital or acquired • Failure of conduction from atrium to ventricle • Slow heart rate and pauses • Long pause may result in ventricular fibrillation

37. Undiagnosed Underlying Problems Structural Congenital Heart Disease • Coronary artery abnormality • Origin from contralateral aortic sinus • Origin from the pulmonary artery

38. Undiagnosed Underlying Problems Structural Congenital Heart Disease

39. Undiagnosed Underlying Problems Infectious Etiologies • Myocarditis • Rheumatic Heart Disease

40. Undiagnosed Underlying Problems Connective Tissue Disease • Marfan Syndrome • Ehlers-Danlos Syndrome

41. Previously Diagnosed Underlying Problems Congenital Heart Disease • Tetralogy of Fallot • Aortic Stenosis

42. No Underlying Problem • Commotio cordis • Traumatic Aortic dissection • Exercise-induced asthma and respiratory arrest • Exercise-induced anaphylaxis • Malignant hyperthermia • Heat stroke • Sickle cell • Rhabdomyolysis • Head trauma • Spine trauma • Non-penetrating neck blow with rupture of cerebral artery • Drug abuse

43. No Underlying Problem Commotio Cordis • Ventricular fibrillation • Blow to chest over the heart • Occurs at critical time during cardiac cycle

44. No Underlying Problem Commotio Cordis

45. No Underlying Problem Commotio Cordis • Avoidance • Chest protectors and vests • May offer false sense of security • Rapid defibrillation • AED

46. The Solutions Rapid Response • Early recognition • Early activation of EMS system • Early CPR • Early defibrillation • Early advanced life support

47. The Status Are we ready? • 2004 AHA Scientific Statement • 80% of parents assumed that teachers were trained in CPR • 40% of teachers had not completed CPR course

48. The Plan 2004 AHA Scientific Statement • Medical Emergency Response Plans (MERP) • Effective and efficient communication throughout the school campus • Coordinated and practiced response plan • Risk reduction • CPR training • Automated external defibrillator

49. The Plan Effective and efficient communication throughout the school campus • Cell phones, walkie talkies, intercoms • Especially important on sports fields • Local EMS activation (911) • Assignment of responsibilities

50. The Plan Coordinated and practiced response plan • Plan development • School nurse • Physicians • Local EMS • Plan practice • Unannounced practice drills • Assessment of time intervals