harvard medical school beth israel deaconess medical center noninvasive cardiovascular evaluation of...

Harvard Medical School

Beth Israel Deaconess Medical Center

Noninvasive Noninvasive Cardiovascular Evaluation Cardiovascular Evaluation of the Competitive Athleteof the Competitive Athlete

Gregory Piazza, M.D.Gregory Piazza, M.D.

Beth Israel Deaconess Medical CenterBeth Israel Deaconess Medical Center

March 19, 2008March 19, 2008



Death on the Soccer FieldDeath on the Soccer Field• Antonio Puerta, a midfielder for Sevilla Antonio Puerta, a midfielder for Sevilla

FC, collapsed during a game on FC, collapsed during a game on August 25, 2007.August 25, 2007.

• He regained consciousness and was He regained consciousness and was walked to the locker room where he walked to the locker room where he collapsed again.collapsed again.

• He was resuscitated and brought to He was resuscitated and brought to the ICU of a nearby hospital.the ICU of a nearby hospital.

• He suffered multiple prolonged He suffered multiple prolonged cardiac arrests over the next several cardiac arrests over the next several hours resulting in anoxic brain injury hours resulting in anoxic brain injury and multisystem organ failure.and multisystem organ failure.

• He died 3 days after his initial collapse He died 3 days after his initial collapse at age 22.at age 22.

• Work-up revealed arrhythmogenic Work-up revealed arrhythmogenic right ventricular cardiomyopathy right ventricular cardiomyopathy (ARVC).(ARVC). Antonio Puerta (November

26, 1984 – August 28, 2007)

http://soccernet.espn.go.com/news/story?id=457723&cc=5901



OverviewOverview

• Although rare, sudden cardiac deaths Although rare, sudden cardiac deaths (SCD) among young competitive athletes (SCD) among young competitive athletes have substantial emotional and social have substantial emotional and social impact upon the lay public and medical impact upon the lay public and medical community.community.

• Because competitive athletes are often Because competitive athletes are often thought to exemplify health and thought to exemplify health and invulnerability, their sudden deaths seem invulnerability, their sudden deaths seem counterintuitive.counterintuitive.

N Engl J Med 2003;349:11



OverviewOverview

• Even with widespread availability of Even with widespread availability of portable automated defibrillators at portable automated defibrillators at sporting events, the mortality for athletes sporting events, the mortality for athletes after syncope or cardiac arrest remains after syncope or cardiac arrest remains high.high.

• An improved understanding of conditions An improved understanding of conditions that predispose to SCD among trained that predispose to SCD among trained athletes has lead to a great interest in pre-athletes has lead to a great interest in pre-participation screening.participation screening.

N Engl J Med 2003;349:11



ObjectivesObjectives

• Describe the physiological adaptations of Describe the physiological adaptations of the cardiovascular system to athletic the cardiovascular system to athletic trainingtraining

• Highlight the epidemiology and causes of Highlight the epidemiology and causes of SCD in competitive athletesSCD in competitive athletes

• Discuss the role of noninvasive testing in Discuss the role of noninvasive testing in the evaluation of competitive athletesthe evaluation of competitive athletes

• Review the recommendations for pre-Review the recommendations for pre-participation screeningparticipation screening



The Physiological Adaptations in The Physiological Adaptations in the Trained Athletethe Trained Athlete

• Athletic training for competitive endurance Athletic training for competitive endurance (aerobic) or isometric (static or power) sports (aerobic) or isometric (static or power) sports results in characteristic changes in cardiac results in characteristic changes in cardiac structure and function.structure and function.

• This physiological form of left ventricular (LV) This physiological form of left ventricular (LV) hypertrophy is known as the “athlete’s heart” and hypertrophy is known as the “athlete’s heart” and must be distinguished from pathological must be distinguished from pathological conditions that may predispose to SCD.conditions that may predispose to SCD.

• Depending on the nature of the exercise training Depending on the nature of the exercise training benign increases in LV mass, wall thickness, benign increases in LV mass, wall thickness, and cavity size as well as left atrial volume may and cavity size as well as left atrial volume may be observed in healthy athletes.be observed in healthy athletes.

N Engl J Med 2003;349:11



The Physiological Adaptations in The Physiological Adaptations in the Trained Athletethe Trained Athlete

Endurance Training Isometric Training

•Increase in LV cavity size

•Minimal increase in LV wall thickness

•Increase in LV wall thickness out of proportion to increase in cavity size

Circulation 2000;101:336



The Athlete’s HeartThe Athlete’s Heart

Gray area of overlap between the “athlete’s heart” and cardiomyopathies.

N Engl J Med 2003;349:11



The Athlete’s HeartThe Athlete’s Heart• The physiological changes of the athlete’s heart have The physiological changes of the athlete’s heart have

been evaluated by cardiac MRI and 3-D echo.been evaluated by cardiac MRI and 3-D echo.• In a study of 30 patients, members of a men’s In a study of 30 patients, members of a men’s

professional rowing team were compared with sedentary professional rowing team were compared with sedentary untrained male subjects.untrained male subjects.

• Each patient underwent evaluation with 3-D echo and Each patient underwent evaluation with 3-D echo and cardiac MRI.cardiac MRI.

• While 2-D echo significantly underestimated While 2-D echo significantly underestimated measurements, 3-D echo demonstrated good agreement measurements, 3-D echo demonstrated good agreement with cardiac MRI.with cardiac MRI.

• Compared with sedentary subjects, athletes had Compared with sedentary subjects, athletes had significantly increased LVEDV, LVESV, and LV mass.significantly increased LVEDV, LVESV, and LV mass.

• There were no differences in LVEF or the ratio of LV There were no differences in LVEF or the ratio of LV mass to LVEDV (LV remodeling index).mass to LVEDV (LV remodeling index).

Heart 2006;92:975



The Athlete’s HeartThe Athlete’s Heart

• In another study, 23 male and 20 female In another study, 23 male and 20 female endurance athletes were compared with age-endurance athletes were compared with age-matched controls using cardiac MRI.matched controls using cardiac MRI.

• Male and female athletes demonstrated similar Male and female athletes demonstrated similar increases in LV and RV volumes and mass increases in LV and RV volumes and mass indices compared with controls.indices compared with controls.

• No gender-specific differences in the effect of No gender-specific differences in the effect of training on LV and RV volumes, mass indices, training on LV and RV volumes, mass indices, ejection fractions, and LV to RV ratios of volume ejection fractions, and LV to RV ratios of volume and mass indices were noted. and mass indices were noted.

J Magn Reson Imaging 2006;24:297



Competitive SportsCompetitive Sports

uptodateonline.com

Classification of sports based on peak static and dynamic components achieved during competition.



Extrinsic Risk Factors for SCDExtrinsic Risk Factors for SCD• The risk of SCD in competitive sports increases The risk of SCD in competitive sports increases

with “burst” exertion (rapid acceleration and with “burst” exertion (rapid acceleration and deceleration; common in basketball, tennis, and deceleration; common in basketball, tennis, and soccer).soccer).

• Extreme environmental conditions (temperature, Extreme environmental conditions (temperature, humidity, and altitude) that affect blood volume humidity, and altitude) that affect blood volume and electrolyte balance also contribute to the and electrolyte balance also contribute to the risk.risk.

• Progressive and systematic training to achieve Progressive and systematic training to achieve higher levels of conditioning and performance higher levels of conditioning and performance may further increase the risk by resulting in a may further increase the risk by resulting in a total cardiovascular demand that often exceeds total cardiovascular demand that often exceeds that of competition.that of competition.

Circulation 2004;109:2807J Am Coll Cardiol 2005;45:1364



Other Extrinsic Risk Factors for Other Extrinsic Risk Factors for SCDSCD

• Cocaine abuseCocaine abuse

• Amphetamine abuseAmphetamine abuse

• Performance enhancing drugs Performance enhancing drugs (anabolic steroids)(anabolic steroids)

• Dietary and nutritional supplements Dietary and nutritional supplements (including ephedra-containing products)(including ephedra-containing products)

N Engl J Med 2001;345:351J Am Coll Cardiol 2002;39:1083



Epidemiology of Sudden Cardiac Epidemiology of Sudden Cardiac DeathDeath

• Although likely underestimated, the incidence of Although likely underestimated, the incidence of SCD among competitive athletes appears to be SCD among competitive athletes appears to be low, ranging from 1 per 50,000 to 1 per 300,000.low, ranging from 1 per 50,000 to 1 per 300,000.

• In a study of Minnesota high school athletes, the In a study of Minnesota high school athletes, the incidence of SCD was 1 in 200,000.incidence of SCD was 1 in 200,000.

• In a study of nearly 220,000 marathon runners, In a study of nearly 220,000 marathon runners, SCD occurred in 4 individuals.SCD occurred in 4 individuals.– None had any prior cardiac symptomsNone had any prior cardiac symptoms– 2 had competed in several previous marathons2 had competed in several previous marathons– 3 had coronary disease on autopsy3 had coronary disease on autopsy

JAMA 1996;276:1999J Am Coll Cardiol 1998;32:1881J Am Coll Cardiol 1996;28:428



Causes of Sudden Cardiac DeathCauses of Sudden Cardiac Death

• Causes of SCD in athletes vary by age Causes of SCD in athletes vary by age and geographic location.and geographic location.

• Among young competitive athletes (< 35 Among young competitive athletes (< 35 years old) in the U.S., inherited or years old) in the U.S., inherited or congenital heart conditions (such as congenital heart conditions (such as hypertrophic cardiomyopathy) are the hypertrophic cardiomyopathy) are the most common etiologies.most common etiologies.

• Among “masters” athletes (> 35 years old), Among “masters” athletes (> 35 years old), coronary artery disease (CAD) appears to coronary artery disease (CAD) appears to be the predominant cause of SCD.be the predominant cause of SCD.

J Am Coll Cardiol 2003;41:974Am J Cardiol 1980;45:1292



Causes of Sudden Cardiac Death Causes of Sudden Cardiac Death in Young Athletesin Young Athletes

• In a U.S. registry of 236 young competitive athletes with In a U.S. registry of 236 young competitive athletes with SCD and structural heart disease on autopsy, the SCD and structural heart disease on autopsy, the following conditions were reported:following conditions were reported:– Hypertrophic cardiomyopathy (HCM)(36%)Hypertrophic cardiomyopathy (HCM)(36%)– Anomalous coronary artery (13%)Anomalous coronary artery (13%)– Myocarditis (7%)Myocarditis (7%)– Ruptured aortic aneurysm (4%)Ruptured aortic aneurysm (4%)– ARVC (4%)ARVC (4%)– Myocardial bridging (4%)Myocardial bridging (4%)– Aortic stenosis (3%)Aortic stenosis (3%)– CAD (3%)CAD (3%)– Idiopathic dilated cardiomyopathy (3%)Idiopathic dilated cardiomyopathy (3%)– Mitral valve prolapse (MVP)(3%)Mitral valve prolapse (MVP)(3%)

J Am Coll Cardiol 2003;41:974





Distribution of causes of SCD in 1435 young competitive athletes. From the Minneapolis Heart Institute Foundation Registry, 1980 to 2005.




• In an analysis of data from over 6 million In an analysis of data from over 6 million U.S. military recruits U.S. military recruits ≤ 35 years old≤ 35 years old, 64 , 64 exercise-related deaths were due to an exercise-related deaths were due to an identifiable structural abnormality:identifiable structural abnormality:– Anomalous coronary artery (33%)Anomalous coronary artery (33%)– Myocarditis (20%)Myocarditis (20%)– CAD (16%)CAD (16%)– HCM (13%)HCM (13%)

Ann Intern Med 2004;141:829




• In contrast, a series of 49 young athletes In contrast, a series of 49 young athletes with SCD from Northern Italy with SCD from Northern Italy demonstrated the following distribution:demonstrated the following distribution:– ARVC (22%)ARVC (22%)– CAD (18%)CAD (18%)– Anomalous coronary artery (12%)Anomalous coronary artery (12%)– MVP (10%)MVP (10%)– Myocarditis (6%)Myocarditis (6%)– HCM (2%)HCM (2%)

N Engl J Med 1998;339:364



Hypertrophic CardiomyopathyHypertrophic Cardiomyopathy• Incidence is Incidence is

approximately 1 in 500.approximately 1 in 500.• It is a heterogeneous It is a heterogeneous

genetic disorder resulting genetic disorder resulting in LV hypertrophy and in LV hypertrophy and fibrosis.fibrosis.

• Sudden death is most Sudden death is most likely due to reentrant likely due to reentrant ventricular ventricular tachyarrhythmias.tachyarrhythmias.

• Most patients have an Most patients have an abnormal ECG.abnormal ECG.

• May be diagnosed by May be diagnosed by echo and cardiac MRI.echo and cardiac MRI.

Marked septal hypertrophy with SAM

Late gadolinium enhancement consistent with myocardial fibrosis

JAMA 2002;287:1308



Anomalous Coronary AnatomyAnomalous Coronary Anatomy• Incidence is likely underestimated.Incidence is likely underestimated.• In SCD, most common anomaly is In SCD, most common anomaly is

a left main coronary artery a left main coronary artery originating from the right sinus of originating from the right sinus of Valsalva.Valsalva.

• May be suggested by chest pain or May be suggested by chest pain or syncope with exercise but often syncope with exercise but often SCD is the first symptom.SCD is the first symptom.

• Mechanism of ischemia is likely Mechanism of ischemia is likely kinking or compression of the kinking or compression of the anomalous artery between the anomalous artery between the aorta and pulmonary trunk.aorta and pulmonary trunk.

• ECG and echo are often normal.ECG and echo are often normal.• Best diagnosed by cardiac MRI, Best diagnosed by cardiac MRI,

CT, or catheterization.CT, or catheterization. Two patients with left main coronary arteries originating from right sinus of Valsalva




MyocarditisMyocarditis• May be preceded by a viral illness.May be preceded by a viral illness.• Clinical findings may include chest Clinical findings may include chest

pain and heart failure symptoms in pain and heart failure symptoms in an otherwise healthy young person.an otherwise healthy young person.

• ECG often demonstrates diffuse ECG often demonstrates diffuse repolarization changes.repolarization changes.

• SCD is likely due to ventricular SCD is likely due to ventricular arrhythmias or atrioventricular arrhythmias or atrioventricular conduction disease.conduction disease.

• May be suggested by LV systolic May be suggested by LV systolic dysfunction (as detected by echo, dysfunction (as detected by echo, cardiac MRI, or cath) in the absence cardiac MRI, or cath) in the absence of CAD.of CAD.

• Cardiac MRI may demonstrate Cardiac MRI may demonstrate focally increased T2-signal focally increased T2-signal consistent with myocardial consistent with myocardial inflammation and late gadolinium inflammation and late gadolinium enhancement suggestive of fibrosis.enhancement suggestive of fibrosis.

Inferolateral and lateral hypokinesis in a young patient with myocarditis

Late gadolinium enhancement of the inferolateral and lateral wall in the same patient



Aortic Aneurysm and DissectionAortic Aneurysm and Dissection• In young athletes, aortic aneurysm and dissection is In young athletes, aortic aneurysm and dissection is

most often associated with aortopathy.most often associated with aortopathy.• Closely linked with inherited connective tissue Closely linked with inherited connective tissue

disorders (Marfan’s syndrome).disorders (Marfan’s syndrome).• Marfan’s is inherited in an autosomal dominant fashion Marfan’s is inherited in an autosomal dominant fashion

with an incidence of 1 in 10,000 to 20,000.with an incidence of 1 in 10,000 to 20,000.• Characteristic morphological findings (arachnodactyly, Characteristic morphological findings (arachnodactyly,

hyperflexible joints) may be noted on examination.hyperflexible joints) may be noted on examination.• SCD occurs due to aortic aneurysm rupture or SCD occurs due to aortic aneurysm rupture or

dissection.dissection.• Diagnosed on basis of clinical criteria.Diagnosed on basis of clinical criteria.• Echo is recommended to evaluate for aortic disease Echo is recommended to evaluate for aortic disease

(including AR).(including AR).• Cardiac MRI and CT also detect aortic pathology.Cardiac MRI and CT also detect aortic pathology.




Arrhythmogenic Right Arrhythmogenic Right Ventricular CardiomyopathyVentricular Cardiomyopathy

• Characterized by fibrofatty infiltration of Characterized by fibrofatty infiltration of the RV free wall (may affect the LV).the RV free wall (may affect the LV).

• Symptoms include exercise induced Symptoms include exercise induced palpitations, presyncope, or syncope.palpitations, presyncope, or syncope.

• SCD is due to catecholamine-sensitive SCD is due to catecholamine-sensitive ventricular arrhythmias.ventricular arrhythmias.

• ECG findings include increased QRS ECG findings include increased QRS duration, epsilon waves in V1-2, and T duration, epsilon waves in V1-2, and T wave inversions in the right wave inversions in the right precordium.precordium.

• Imaging may demonstrate RV Imaging may demonstrate RV dilatation and aneurysms.dilatation and aneurysms.

• Echo and cardiac MRI are the most Echo and cardiac MRI are the most widely used noninvasive tests for widely used noninvasive tests for ARVC.ARVC.

Epsilon waves

Increased signal on T1-weighted imaging in the RV free wall (left) and decreased signal on fat suppressed imaging (right)




Myocardial BridgingMyocardial Bridging• Myocardial bridging occurs when Myocardial bridging occurs when

a portion of an epicardial a portion of an epicardial coronary artery “tunnels” into the coronary artery “tunnels” into the myocardium.myocardium.

• Systolic vessel compression and Systolic vessel compression and delayed diastolic relaxation delayed diastolic relaxation impair coronary blood flow in the impair coronary blood flow in the intramyocardial segment.intramyocardial segment.

• Although usually of little clinical Although usually of little clinical consequence, myocardial consequence, myocardial bridging may infrequently result in bridging may infrequently result in exertional angina, infarction, and exertional angina, infarction, and SCD.SCD.

• Myocardial bridging may be Myocardial bridging may be diagnosed on cardiac CT, MRI, or diagnosed on cardiac CT, MRI, or catheterization.catheterization.

Contrast-enhanced EBCT image revealing an intramyocardial segment of the LAD

N Engl J Med 2003;349:1047



Aortic StenosisAortic Stenosis

• Aortic stenosis (AS) in young athletes is most often due Aortic stenosis (AS) in young athletes is most often due to congenital abnormalities of the aortic valve.to congenital abnormalities of the aortic valve.

• Most common abnormality is a bicuspid aortic valve.Most common abnormality is a bicuspid aortic valve.• More unusual etiologies include subvalvar and More unusual etiologies include subvalvar and

supravalvar aortic stenoses.supravalvar aortic stenoses.• Nearly all adult patients with SCD and congenital AS Nearly all adult patients with SCD and congenital AS

experience preceding symptoms.experience preceding symptoms.• The majority of children may not have symptoms before The majority of children may not have symptoms before

SCD.SCD.• Echo is the test of choice (although cardiac CT or MRI Echo is the test of choice (although cardiac CT or MRI

may be required to assess for concomitant aortic may be required to assess for concomitant aortic pathology).pathology).

Circulation 1993;87:I16



Premature Coronary Artery Premature Coronary Artery DiseaseDisease

• CAD in young patients is frequently CAD in young patients is frequently asymptomatic.asymptomatic.

• Therefore, its incidence is likely underestimated.Therefore, its incidence is likely underestimated.• In an autopsy study, advanced coronary In an autopsy study, advanced coronary

stenoses were noted in 20% of men and 8% of stenoses were noted in 20% of men and 8% of women aged 30-34 years.women aged 30-34 years.

• 19% and 8% of men and women aged 30-34 19% and 8% of men and women aged 30-34 years, respectively, had years, respectively, had ≥ 40% stenosis of the ≥ 40% stenosis of the LAD.LAD.

• Coronary artery disease is the most common Coronary artery disease is the most common cause of SCD among “masters” athletes (> 35 cause of SCD among “masters” athletes (> 35 years old).years old).




Idiopathic Dilated Idiopathic Dilated CardiomyopathyCardiomyopathy

• Idiopathic cardiomyopathy Idiopathic cardiomyopathy is a relatively uncommon is a relatively uncommon cause of SCD in young cause of SCD in young competitive athletes (3%).competitive athletes (3%).

• The mechanism of SCD is The mechanism of SCD is most often reentrant most often reentrant ventricular tachyarrhythmia ventricular tachyarrhythmia originating from areas of originating from areas of abnormal myocardium.abnormal myocardium.

• Bradyarrhythmia or Bradyarrhythmia or asystole may lead to SCD asystole may lead to SCD if cardiomyopathic process if cardiomyopathic process involves the conduction involves the conduction system.system.

Late gadolinium enhancement in a patient with cardiomyopathy and normal coronary arteries



Mitral Valve ProlapseMitral Valve Prolapse• Although its relationship to Although its relationship to

tachyarrhythmia has been tachyarrhythmia has been controversial, MVP is associated with controversial, MVP is associated with an increased risk of SCD.an increased risk of SCD.

• However, the increased risk of SCD However, the increased risk of SCD seems to correlate with the degree of seems to correlate with the degree of mitral valve pathology and MR.mitral valve pathology and MR.

• In one study, the annual SCD In one study, the annual SCD mortality was significantly increased mortality was significantly increased (from 0.9% to 1.9%) in patients with (from 0.9% to 1.9%) in patients with advanced mitral valve pathology advanced mitral valve pathology compared with patients with isolated compared with patients with isolated MVP (no MR) or the general MVP (no MR) or the general population.population.

• Late gadolinium enhancement of the Late gadolinium enhancement of the papillary muscles may be noted in papillary muscles may be noted in some patients with MVP suggesting some patients with MVP suggesting the presence of scarring or fibrosis.the presence of scarring or fibrosis.

Late gadolinium enhancement of the anterolateral papillary muscle in a patient with MVP

Am Heart J 1987;113:1298



Other Congenital Heart DiseaseOther Congenital Heart Disease• In addition to arrhythmic causes, cyanosis during In addition to arrhythmic causes, cyanosis during

exercise in the setting of adult congenital heart exercise in the setting of adult congenital heart disease with right-to-left shunt may lead to syncope disease with right-to-left shunt may lead to syncope and SCD.and SCD.

• Cardiac arrest is an unusual first presentation of adult Cardiac arrest is an unusual first presentation of adult congenital heart disease as most are symptomatic congenital heart disease as most are symptomatic and therefore diagnosed before SCD.and therefore diagnosed before SCD.

• Adult congenital heart disease may be diagnosed by Adult congenital heart disease may be diagnosed by echo, cardiac CT, or MRI.echo, cardiac CT, or MRI.

• Cardiac MRI currently offers the best definition of the Cardiac MRI currently offers the best definition of the complex anatomy of repaired and unrepaired complex anatomy of repaired and unrepaired congenital heart disease.congenital heart disease.



Sudden Cardiac Death in the Sudden Cardiac Death in the Absence of Structural Heart DiseaseAbsence of Structural Heart Disease• SCD in competitive athletes may also occur in SCD in competitive athletes may also occur in

the absence of structural heart disease.the absence of structural heart disease.• Causes of SCD in structurally “normal” hearts Causes of SCD in structurally “normal” hearts

include inherited arrhythmia syndromes such as:include inherited arrhythmia syndromes such as:– Long QT syndromeLong QT syndrome– Brugada syndromeBrugada syndrome– Catecholaminergic polymorphic VTCatecholaminergic polymorphic VT– Wolf-Parkinson-White syndromeWolf-Parkinson-White syndrome– Congenital short QT syndromeCongenital short QT syndrome

• In addition, idiopathic VF and commotio cordis In addition, idiopathic VF and commotio cordis may result in SCD among competitive athletes.may result in SCD among competitive athletes.



Long QT SyndromesLong QT Syndromes

• Often acquired, long QT syndrome can be Often acquired, long QT syndrome can be inherited.inherited.

• Long QT syndromes may result in polymorphic Long QT syndromes may result in polymorphic VT (torsade de pointes) and SCD.VT (torsade de pointes) and SCD.

• Among inherited long QT syndromes, Among inherited long QT syndromes, precipitants and prognosis vary.precipitants and prognosis vary.

N Engl J Med 2008;113:1298

Examples of long QT syndromes



Brugada SyndromeBrugada Syndrome

• Autosomal dominant Autosomal dominant disorder resulting in disorder resulting in increased risk of SCD.increased risk of SCD.

• Multiple mutations in Multiple mutations in the cardiac sodium the cardiac sodium channel SCN5A have channel SCN5A have been described.been described.

• Characterized by Characterized by RBBB and ST RBBB and ST segment elevations in segment elevations in V1-V3 on ECG.V1-V3 on ECG. Typical ECG pattern for Brugada

Syndrome

uptodateonline.com



Catecholaminergic Polymorphic Catecholaminergic Polymorphic VTVT

• Also known as familial polymorphic VT, Also known as familial polymorphic VT, catecholaminergic polymorphic VT typically catecholaminergic polymorphic VT typically manifests itself in childhood or adolescence.manifests itself in childhood or adolescence.

• SCD may occur in the setting of emotional or SCD may occur in the setting of emotional or physical stress.physical stress.

• Like LQT1, SCD while swimming has been Like LQT1, SCD while swimming has been described.described.

• Several mutations have been described Several mutations have been described including in the cardiac ryanodine receptor and including in the cardiac ryanodine receptor and calsequestrin 2 genes.calsequestrin 2 genes.




Wolf-Parkinson-WhiteWolf-Parkinson-White

• WPW syndrome has WPW syndrome has been associated with an been associated with an increased risk of SCD.increased risk of SCD.

• The mechanism of SCD The mechanism of SCD is most often atrial is most often atrial fibrillation or AVNRT that fibrillation or AVNRT that degenerates to VF.degenerates to VF.

• In up to 25% of patients In up to 25% of patients with SCD due to WPW, with SCD due to WPW, pre-excitation and pre-excitation and arrhythmias have been arrhythmias have been previously undiagnosed.previously undiagnosed.

J Am Coll Cardiol 1991;18:1711uptodateonline.com

Typical pre-excitation pattern for WPW



Congenital Short QT SyndromeCongenital Short QT Syndrome

• Congenital short QT syndrome is a rare Congenital short QT syndrome is a rare autosomal dominant disorder associated with autosomal dominant disorder associated with SCD due to VF.SCD due to VF.

• Multiple genetic abnormalities have been Multiple genetic abnormalities have been described including gain-of-function mutations in described including gain-of-function mutations in potassium channel genes.potassium channel genes.

• Short QT is defined as a corrected QT interval Short QT is defined as a corrected QT interval (QTc) (QTc) ≤≤ 340 msec. 340 msec.

• Patients often develop atrial fibrillation at a Patients often develop atrial fibrillation at a young age .young age .

• Not all patients with short QTc carry an Not all patients with short QTc carry an increased risk of SCD.increased risk of SCD.




Idiopathic VFIdiopathic VF

• Also called “primary electrical disease,” Also called “primary electrical disease,” idiopathic VF is diagnosed when SCD idiopathic VF is diagnosed when SCD occurs in a structurally normal heart and occurs in a structurally normal heart and other arrhythmic disorders are excluded.other arrhythmic disorders are excluded.

• May account for up to 5% of SCD cases.May account for up to 5% of SCD cases.

• Idiopathic VF is more common in men and Idiopathic VF is more common in men and has a mean onset of 36 years.has a mean onset of 36 years.

• A history of syncope precedes SCD in up A history of syncope precedes SCD in up to 25% of patients.to 25% of patients.

Am Heart J 1990;120:661



Commotio CordisCommotio Cordis• Commotio cordis describes SCD that occurs following Commotio cordis describes SCD that occurs following

precordial trauma.precordial trauma.• A registry analysis revealed that 62% of cases occurred A registry analysis revealed that 62% of cases occurred

during organized or recreational sporting activities during organized or recreational sporting activities (baseball, hockey).(baseball, hockey).

• In an animal model, low-energy impact to the chest wall In an animal model, low-energy impact to the chest wall just before the peak of the T wave produced VF, while just before the peak of the T wave produced VF, while impact during the QRS complex produced complete impact during the QRS complex produced complete heart block.heart block.

• Frequency of VF was related to the hardness of the Frequency of VF was related to the hardness of the projectile and velocity of impact.projectile and velocity of impact.

• In one series, only 16% of individuals survived an In one series, only 16% of individuals survived an arrhythmic event in the setting of commotio cordis.arrhythmic event in the setting of commotio cordis.

JAMA 2002;287:1142N Engl J Med 1998; 338:1805



Commotio CordisCommotio Cordis

N Engl J Med 2003;349:11

Fatal commotio cordis in a 14-year-old boy during a karate match.



Syncope in Competitive AthletesSyncope in Competitive Athletes

• Syncope in competitive athletes without known Syncope in competitive athletes without known structural heart disease is most often due to structural heart disease is most often due to neurocardiogenic, or vasovagal, mechanisms.neurocardiogenic, or vasovagal, mechanisms.

• However, the diagnosis of neurocardiogenic However, the diagnosis of neurocardiogenic syncope in this patient population is a diagnosis syncope in this patient population is a diagnosis of exclusion.of exclusion.

• Careful evaluation warrants a detailed history, Careful evaluation warrants a detailed history, physical examination, and ECG.physical examination, and ECG.

• Echocardiography, exercise treadmill testing, Echocardiography, exercise treadmill testing, cardiac MRI, and electrophysiological testing cardiac MRI, and electrophysiological testing may be required to exclude structural and may be required to exclude structural and dysrhythmia-related causes of syncope.dysrhythmia-related causes of syncope.



Cardiovascular Events in Cardiovascular Events in SpectatorsSpectators

• The emotional stress of The emotional stress of watching competitive sports watching competitive sports may increase the risk of may increase the risk of cardiovascular events.cardiovascular events.

• A recent study demonstrated A recent study demonstrated an increased incidence of an increased incidence of cardiac emergencies among cardiac emergencies among German men and women on German men and women on days that the German team days that the German team was playing a 2006 World Cup was playing a 2006 World Cup match compared to non-match match compared to non-match days (incidence ratio 2.66, days (incidence ratio 2.66, 95% CI 2.33-3.04; p<0.001.95% CI 2.33-3.04; p<0.001.

• The incidence of STEMI, The incidence of STEMI, NSTEMI, and arrhythmia NSTEMI, and arrhythmia increased by a factor of 2.5, increased by a factor of 2.5, 2.6, and 3.1, respectively, 2.6, and 3.1, respectively, during match days.during match days.

Daily cardiovascular events from May 1 to July 31 in 2003, 2005, and 2006.Numbers 1-7 correspond to German soccer matches during the 2006 World Cup (8 = Final, Italy v. France).

N Engl J Med 2008;358:475



ScreeningScreening• Due to the devastating nature of SCD and the potential Due to the devastating nature of SCD and the potential

to prevent such deaths by diagnosing associated to prevent such deaths by diagnosing associated disorders noninvasively, clinicians have a strong disorders noninvasively, clinicians have a strong incentive to screen athletes.incentive to screen athletes.

• However, the following obstacles prevent widespread However, the following obstacles prevent widespread screening with noninvasive testing:screening with noninvasive testing:– Large number of competitive athletes (8 million in the U.S., Large number of competitive athletes (8 million in the U.S.,

including high school, collegiate, professional)including high school, collegiate, professional)– Low prevalence of underlying congenital heart diseaseLow prevalence of underlying congenital heart disease– Number of disorders to consider, each with different optimal Number of disorders to consider, each with different optimal

testing modalitiestesting modalities– Impact of false-positive studies (substantial when screening for Impact of false-positive studies (substantial when screening for

rare diseases; possible medicolegal implications)rare diseases; possible medicolegal implications)– No randomized trials evaluating the impact of pre-participation No randomized trials evaluating the impact of pre-participation

screening on the incidence of SCDscreening on the incidence of SCD

N Engl J Med 2003;349:11



ScreeningScreening• In an observational series from Italy, a In an observational series from Italy, a

mandatory screening program including ECG mandatory screening program including ECG was associated with a decrease in the annual was associated with a decrease in the annual incidence of SCD in athletes from 3.6 to 0.4 per incidence of SCD in athletes from 3.6 to 0.4 per 100,000 person-years from 1980 to 2004.100,000 person-years from 1980 to 2004.

• AHA guidelines differ from those of the AHA guidelines differ from those of the European Society of Cardiology (ESC) and the European Society of Cardiology (ESC) and the International Olympic Committee (IOC) such that International Olympic Committee (IOC) such that routine noninvasive testing (including ECG) is routine noninvasive testing (including ECG) is not recommended.not recommended.

JAMA 2006;296:1593Circulation 2007;115:1643



AHA Screening AHA Screening RecommendationsRecommendations

• Younger competitive athletes (<35)Younger competitive athletes (<35)– Complete personal/family history and physical examComplete personal/family history and physical exam– Performed by physicians or certified non-physiciansPerformed by physicians or certified non-physicians– q2 years for high school and yearly for college/proq2 years for high school and yearly for college/pro

• Masters athletes (>35)Masters athletes (>35)– Complete personal/family history and physical examComplete personal/family history and physical exam– Exercise testing for moderate-to-high risk patients Exercise testing for moderate-to-high risk patients

(men >40, women >50 with one or more CAD risk (men >40, women >50 with one or more CAD risk factors; symptoms suggestive of CAD; factors; symptoms suggestive of CAD; ≥≥65 regardless 65 regardless of risk factors/symptoms)of risk factors/symptoms)

• Recreational athletesRecreational athletes– No explicit AHA guidelines; exercise testing No explicit AHA guidelines; exercise testing

recommended in patients at high risk for CADrecommended in patients at high risk for CAD




12-Element AHA Pre-Participation 12-Element AHA Pre-Participation Screening RecommendationsScreening Recommendations


• Personal history (confirmed by parent if minor)Personal history (confirmed by parent if minor)– Exertional chest discomfortExertional chest discomfort– Unexplained syncope/presyncopeUnexplained syncope/presyncope– Excessive exertional fatigue/dyspneaExcessive exertional fatigue/dyspnea– Prior heart murmurPrior heart murmur– Elevated blood pressureElevated blood pressure

• Family history (confirmed by parent if minor)Family history (confirmed by parent if minor)– Premature death due to heart disease before age 50Premature death due to heart disease before age 50– Disability due to heart disease in relative <50Disability due to heart disease in relative <50– Specific knowledge of certain cardiac conditions (HCM, other CM, ion Specific knowledge of certain cardiac conditions (HCM, other CM, ion

channelopathy, Marfan’s, arrhythmias)channelopathy, Marfan’s, arrhythmias)• Physical examinationPhysical examination

– Cardiac exam (supine and standing)Cardiac exam (supine and standing)– Femoral pulsesFemoral pulses– Physical stigmata of Marfan’sPhysical stigmata of Marfan’s– Bilateral blood pressure readingsBilateral blood pressure readings

*Positive finding of any 1 element warrants referral to cardiovascular specialist *Positive finding of any 1 element warrants referral to cardiovascular specialist +/- further testing+/- further testing



Activity Restriction Activity Restriction RecommendationsRecommendations

• The 26The 26thth Bethesda Conference guidelines have Bethesda Conference guidelines have established clear recommendations for the athletic established clear recommendations for the athletic eligibility and restriction of athletes with conditions eligibility and restriction of athletes with conditions associated with SCD.associated with SCD.

• The decision to remove athletes from eligibility may be The decision to remove athletes from eligibility may be associated with complex social and medicolegal associated with complex social and medicolegal ramifications.ramifications.

• A U.S. appellate court has ruled that the Bethesda A U.S. appellate court has ruled that the Bethesda Conference report can be used by clinicians to determine Conference report can be used by clinicians to determine an athlete’s eligibility.an athlete’s eligibility.

• Guidelines such as the Bethesda Conference report have Guidelines such as the Bethesda Conference report have been endorsed as a means for resolving medicolegal been endorsed as a means for resolving medicolegal disputes involving the eligibility of young athletes.disputes involving the eligibility of young athletes.

N Engl J Med 2003;349:11



ConclusionsConclusions• SCD in competitive athletes may result from a SCD in competitive athletes may result from a

variety of disorders that may be detected by variety of disorders that may be detected by noninvasive testing.noninvasive testing.

• Noninvasive testing must be interpreted carefully Noninvasive testing must be interpreted carefully in order to distinguish the physiological effects of in order to distinguish the physiological effects of exercise training from pathology.exercise training from pathology.

• AHA guidelines do not endorse routine pre-AHA guidelines do not endorse routine pre-participation screening with noninvasive testing.participation screening with noninvasive testing.

• However, noninvasive testing plays a critical role However, noninvasive testing plays a critical role in the evaluation of competitive athletes with in the evaluation of competitive athletes with positive findings on screening history and positive findings on screening history and physical examination.physical examination.

harvard medical school beth israel deaconess medical center noninvasive cardiovascular evaluation of...

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