1. Screening for Sudden Cardiac Death in Athletes and Low-Risk Patients
Cameron Smith

2. Epidemiology The exact incidence of SCD in athletes remains unclear.
Overall incidence is between 1:50,000 and 1:100,000 per year in young athletes 1
A total of 1866 athletes who died suddenly (or survived cardiac arrest), 19+/-6 years of age, were identified throughout the United States from 1980 to 2006 in 38 diverse sports 2

3. Epidemiology
NCAA Data 2015

4. Most common cause of athlete death
The majority of SCD events in athletes are due to malignant arrhythmias, usually sustained VT or VF.
The most common cardiac causes were hypertrophic cardiomyopathy (36%) and congenital coronary artery anomalies (17%). 2
Other major causes include arrhythmogenic right ventricular cardiomyopathy (ARVC) especially in international populations. 3

5. Other causes of Cardiac death
Recommendations and Considerations Related to Preparticipation Screening for Cardiovascular Abnormalities in Competitive Athletes: 2007 Update, Volume: 115, Issue: 12, Pages: , DOI: ( /CIRCULATIONAHA )

6. Other causes of Cardiac death
NCAA 6

7. Other causes of Cardiac death
The most common anomaly associated with SCD is a coronary that courses between the aorta and pulmonary artery

8. Other causes of Cardiac death

9. Who should you screen with EKG?
The USPSTF recommends against screening with resting or exercise ECG to prevent cardiovascular disease events in asymptomatic adults at low risk

10. Screening Algorithm

11. Who should you suspect? History of heart murmur 4
Exertional symptoms 4
Symptoms of Marfan Syndrome
Family History of SCD
Syncope
Further evaluation should be considered for persons with heart or lung disease, bleeding disorders, musculoskeletal problems, history of concussion, or other neurologic disorders.

12. Who should you suspect?
Upwards of approximately 30% of athletes with SCD have been reported to have had symptoms such as chest pain, shortness of breath, performance decline, palpitations, pre-syncope, or syncope leading up to the event

14. Hypertrophic Cardiomyopathy
Autosomal Dominant
Mutation in the Cardiac Sarcomere – β-Myosin Heavy Chain
Prevalence is 1:500 in adults
Histology shows disorganized pattern of hypertrophied myocytes in disarray with replacement fibrosis

16. Hypertrophic Cardiomyopathy
Commonly asymptomatic
Patients may report symptoms of DOE, SOB, orthopnea, PND, chest pain, palpitations, pre-syncope/syncope, fatigue, or edema
Physical Exam
Crescendo-Decrescendo Systolic Murmur best heart at apex and LLSB
Murmur intensifies with Valsalva and standing
Murmur decreases with handgrip, leg-lift, and squatting

17. Hypertrophic Cardiomyopathy
ECG Findings
90% will have abnormal findings
No pathognomonic signs
Most often will show prominent abnormal Q waves, P wave abnormalities, left axis deviation, and deeply inverted T waves
Echo Findings
Increased LV wall thickness in the absence of another cause
LVH (particularly asymmetrical LVH)
Increased LVOT gradient
Systolic anterior motion of the mitral valve leaflets

18. ECG is reproduced from Hansen & Merchant (2007). 

20. Hypertrophic Cardiomyopathy
Diagnosis
Using Echo/CMR – LV wall thickening >15mm anywhere in the LV without any other identifiable cause (HTN, AS, Athlete’s Heart)
Suggest doing cardiovascular magnetic resonance in all patients with suspected or diagnosed HCM to most reliably assess LV morphology, including maximal LV wall thickness

21. Hypertrophic Cardiomyopathy
Treatment and Prognosis
Patients with symptoms of HF should be treated with
Beta Blockers
Non-dihydropyridine CCB (Verapamil/Diltiazem)
Disopyramide
Avoid vasodilators or diuretics, which may worsen LVOT obstruction
Asymptomatic patients generally do not need Rx

23. References
1. Landry CH, Allan KS, Connelly KA, et al. Sudden Cardiac Arrest during Participation in Competitive Sports. N Engl J Med 2017; 377:1943.
2. Maron BJ, Doerer JJ, Haas TS, Tierney DM, Mueller FO. Sudden deaths in young competitive athletes: analysis of 1866 deaths in the United States, 1980–2006. Circulation Mar 3;119(8):1085–92.
3. Wasfy MM, Hutter AM, Weiner RB. Sudden Cardiac Death in Athletes. Methodist Debakey Cardiovasc J Apr-Jun;12(2): doi: /mdcj 4. 5.
6. Maron BJ, Douglas PS, Graham TP, Nishimura RA, Thompson PD. Task Force 1: preparticipation screening and diagnosis of cardiovascular disease in athletes. J Am Coll Cardiol Apr 19;45(8):1322–6
7. Marijon E, Uy-Evanado A, Reinier K, Teodorescu C, Narayanan K, Jouven X, Gunson K, Jui J, Chugh SS Circulation Apr 21; 131(16):
8. Harmon KG, Asif IM, Maleszewski JJ et al. Incidence, Cause, and Comparative Frequency of Sudden Cardiac Death in National Collegiate Athletic Association Athletes: A Decade in Review. Circulation Jul 7;132(1):10–9. 9.
10. Maron M. Hypertrophic cardiomyopathy: Clinical manifestations, diagnosis, and evaluation. Up to Date May 08.
11. Robinson A, Kramer C. Imaging in Hypertrophic Cardiomyopathy. American College of Cardiology Apr 24.
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