Summary Cardiac conditions are the most common cause of sudden death in young athletic patients and comprise of hypertrophic cardiomyopathy (most common), coronary artery disease, and commotio cordis. Diagnosis requires a thorough history and physical exam to identify a history of chest pain, palpitations, syncope during exercise, and evaluation for murmurs. An EKG or echocardiogram should be performed when there is a high suspicion of hypertrophic cardiomyopathy. Treatment is focused on prevention with avoidance of vigorous exercise when hypertrophic cardiomyopathy is diagnosed. If commotio cordis develops, prompt treatment with cardiac defibrillation is required for survival. Overview Common conditions affecting athletes include syncope hypertrophic cardiomyopathy coronary artery disease long QT syndrome commotio cordis sudden cardiac death Presentation symptoms history and physical exam is the best screening tool to identify cardiovascular problems in high school athletes chest pain palpitations syncope physical exam pre-participation physicals diastolic murmur warrants further workup II/VI systolic murmur Evaluation EKG normal EKG findings in endurance athletes ventricular hypertrophy primary AV block nonspecific STT wave changes in the lateral leads on ECG resting sinus bradycardia at 40 beats per minute Syncope Overview sudden loss of consciousness caused by a sudden loss of blood pressure a syncopal episode in a young athlete is a red flag for a serious cardiac condition. Epidemiology incidence annual incidence of 7% Demographics age any age sex more common in females than in males risk factors cardiac conditions dehydration female gender Etiology pathophysiology transient loss of consciousness due to decreased cerebral perfusion can be caused by any condition disrupting cerebral perfusion 50% are neurocardiogenic also known as vasovagal syncope increased vasodilation with bradycardia due to decreased sympathetic and increased parasympathetic tone risk factors when standing for prolonged periods hot environments associated conditions cardiovascular disorder arrhythmias cardiac structural abnormalities including myocardial infarction, hypertrophic cardiomyopathy, valvular disease, pulmonary embolism, commotio cordis cerebrovascular disease including stroke, transient ischemic attack, vertebrobasilar insufficiency disruption of vascular tone and blood flow including orthostatic hypotension, carotid sinus syndrome, anemia Presentation symptoms lightheadedness dizziness palpitations sweating physical examination unconsciousness cold clammy skin Treatment medical evaluation requires a medical evaluation prior to returning to athletic activity Hypertrophic Cardiomyopathy Overview a genetic condition causing mutations in the cardiac muscle leading to increased ventricular wall thickness resulting in outflow obstruction, diastolic dysfunction, and increased risk of sudden cardiac death most common cause of cardiac sudden death in young athletic patients Epidemiology incidence 1 in 500 demographics age present from birth diagnosis is usually between 20-30 years of age sex male:female is 1 to 1 females more likely to be symptomatic risk factors hypertension genetic predisposition Etiology pathophysiology abnormal thick or thin cardiac myofilament proteins resulting in abnormal structure and function of the cardiac muscle with hypertrophy of the left ventricular wall and septum leads to asymmetric hypertrophy resulting in left ventricular outflow obstruction most commonly affects the interventricular septum 66% of patients genetics inheritance pattern autosomal dominant with variable penetrance predominantly missense mutations less likely to be frameshift mutation mutations thousands of possible mutations affecting more than a dozen genes including Cardiac troponin T – TNNT2 gene Cardiac troponin I – TNNTI3 gene Myosin regulatory light chain – MYL2 gene Myosin essential light chain – MYL3 gene associated conditions increased risk for sudden cardiac death and arrhythmias Presentation history family history cardiac murmur symptoms dyspnea on exertion chest pain dizziness presyncope or syncope physical exam II/VI systolic crescendo-decrescendo murmur 25% of patients with obstruction at rest 70% of patients with obstruction during provocative maneuvers decreased preload increases murmur intensity Valsalva maneuver diuretics standing a murmur that increases with standing or Valsalva maneuver should raise concern for hypertrophic cardiomyopathy increases with decreased afterload or increased preload caused by dynamic obstruction of blood outflow caused by an enlarged ventricle squatting or handgrip maneuver double carotid pulse arrhythmia double apical pulse Imaging echocardiogram will show nondilated, thickened left ventricular wall thickness compared to normal individuals of the same age. 80% diagnostic accuracy evaluate the structure of cardiac chambers, along with systolic and diastolic function determines the degree of outflow obstruction evaluates for valvular disease cardiac mri gold standard for diagnosis performed in patients in which hypertrophic cardiomyopathy is suspected with inconclusive echocardiogram Studies electrocardiogram most sensitive diagnostic test left ventricular hypertrophy with right atrial enlargement is highly suggestive of hypertrophic cardiomyopathy prominent Q-waves in inferior and lateral leads left axis deviation atrial enlargement inverted t-waves ambulatory electrocardiogram recommended in all patients diagnosed with hypertrophic cardiomyopathy worn for 24-48 hours used in the assessment of ventricular arrhythmias and sudden cardiac death stress test exercise is preferred over pharmacologic stress test used for assessment of left ventricular outflow obstruction tract gradient useful for risk stratification Diagnosis diagnosis is made based on an echocardiogram, electrocardiogram, genetic testing, and family history Treatment lifestyle modifications indications Asymptomatic patients, mild left ventricular hypertrophy, and no outflow obstruction management routine clinical observation repeat echocardiogram as indicated by changes in symptoms maintain hydration avoid vigorous exercise considered an absolute contraindication to vigorous exercise and sports outcomes may participate in sports that require mild to moderate physical activity medical therapy indications symptomatic patients (dyspnea, fatigue, chest pain, syncope) management beta-blockers (metoprolol) first line calcium channel blockers outcomes non-vasodilating beta-blockers can improve symptoms only provides symptomatic relief Complications cardiac complications includes sudden cardiac death, arrhythmias, congestive heart failure, stroke Prognosis 1-2% annual mortality rate Coronary Artery Disease Epidemiology 2nd most common cause of sudden cardiac death most common in older patients Pathophysiology coronary artery disease (CAD) usually seen in older patients risk factors hypertension family history left main coronary artery with abnormal origin is a risk because the artery can become compressed and lead to ischemia Presentation symptoms mostly asymptomatic but when symptoms present they are commonly chest pain palpitations syncope Imaging coronary angiography and MR angiography are gold standards Treatment lifestyle changes healthy eating, stress reduction, quit smoking, lose weight medications b-blocker, aspirin, ACE inhibitors, nitroglycerin, calcium channel blockers surgery angioplasty and stenting coronary artery bypass grafting Commotio Cordis Overview it results in cardiac ventricular fibrillation and is universally fatal unless immediate defibrillation is performed caused by direct impact during ventricular repolarization a rare but catastrophic condition that is caused by blunt chest trauma Epidemiology incidence less than 30 cases per year demographics age average age is 15 years old most common in children and adolescents due to high number of athletes sex male:female ratio is 20 to 1 risk factors contact sports younger age Etiology pathophysiology mechanism of injury traumatic blow to the anterior chest during ventricular repolarization leading to ventricular depolarization resulting in ventricular fibrillation pathoanatomy anterior chest wall blow occurring during the upstroke of the T-wave with enough energy (>50 joules) leading to myocardial cell membrane stretch the upstroke of the T-wave is 1% of the cardiac cycle smaller balls increase risk due to decreased surface area of impact higher energy impacts are more likely to cause structural damage and not isolated ventricular fibrillation results in activation of ion channels through mechanical-electrical coupling resulting in aberrant depolarization resulting in ventricular fibrillation Presentation history patient experiences a sudden blow to the chest, typically during an athletic event symptoms loss of consciousness physical exam pulselessness unconsciousness death Studies electrocardiogram will show ventricular fibrillation Diagnosis diagnosis is made by witnessed blow to the chest followed by collapse with electrocardiogram showing ventricular fibrillation Treatment CPR vs.cardiac defibrillation the best method of treatment is cardiac defibrillation return to sport no restrictions from returning to sport athletes should take precautions against future blows to the chest Prevention chest protectors in baseball and hockey have not yielded the protective results desired Prognosis poor prognosis with a mortality rate of 59% improved mortality rate with early defibrillation Long QT Syndrome overview a prolongation in the ventricular action potential duration, QT interval, potentially leading to cardiac arrhythmias Epidemiology incidence 1 in 2,500 to 10,000 demographics age diagnosis is usually under 20 years of age sex more uncommon in females than in males risk factors genetic predisposition medications anti-arrhythmic, antibiotics (macrolides/fluoroquinolones), antipsychotics Etiology pathophysiology congenital genetic mutation coding for the ion channel proteins leading to increased intracellular positive ion charge, prolonging the QT interval, and increasing risk of arrhythmia acquired electrolyte derangement or medications blocking potassium ion channel leading to increased intracellular positive ion charge and prolonged QT interval during repolarization Genetics inheritance pattern most mutations are autosomal dominant mutations LTQ1 – 45% Chromosome 11 Encodes for KCNQ1 Loss of function mutation Component of potassium efflux channel LTQ2 – 25-40% Chromosome 7 Encodes KCNH2 Component of potassium influx channel LTQ3 – 5-10% Chromosome 3 Encodes SCN5A Component of sodium channel associated conditions Romano Ward Syndrome an abnormality of ventricular repolarization that can lead to sudden cardiac death if not recognized and treated torsades de pointes ventricular tachycardia Presentation history majority of patients are asymptomatic family history or medications leading to acquired long QT syndrome symptoms often times asymptomatic syncope or near-syncope with exercise cardiac arrest palpitations physical examination arrhythmia Studies labs basic metabolic panel and magnesium level further cause QT prolongation Diagnosis ECG is gold standard Treatment sports return to play determination of play by genetic makeup, presentation, and need for pacemaker monitoring with intermittent electrocardiogram no restriction from exercise Complications torsades de pointes can occur from prolonged QT syndrome 50% are asymptomatic Sudden Cardiac Death Overview defined as death resulting from cardiovascular cause occurring within one hour of symptom onset Epidemiology incidence 0.76 to 13 per 100,000 2.8x more common in adolescent and teenage athletes than in non-athletes demographics age Birth to 13 years old is usually due to a congenital abnormality 14 to 24 years old is usually due to hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, congenital coronary anomalies, wolf-parkinson white, and Marfan syndrome sex more common in males than females risk factors increased with age increased risk in males anomalous origin of coronary artery hypertrophic cardiomyopathy Etiology pathophysiology mechanism sudden generation of cardiac arrhythmia leading to ventricular ectopy then sustained ventricular arrhythmia leading to ventricular tachycardia or ventricular fibrillation usually secondary to a pre-existing condition Presentation history family history of sudden cardiac death prior restriction from sports due to cardiac history of heart murmur symptoms syncope chest pain, tightness, pressure or discomfort elevated blood pressure heart murmur pulselessness physical exam blood pressure assessment pulse check auscultation for heart murmur Imaging cardiac MRI coronary angiography echocardiogram Studies labs cardiac enzyme assay genetic testing brugada, lqts, arvc other studies exercise stress test electrophysiology testing electrocardiogram Treatment cardiac resuscitation involving CPR and AED defibrillation Prognosis overall, poor prognosis with >90% mortality rate early recognition and use of an AED significantly improve survival