hypertrophic cardiomyopathy

Hypertrophic Hypertrophic CardiomyopathyCardiomyopathy

Dr. Fuad FarooqDr. Fuad FarooqResident CardiologyResident CardiologyAga Khan University Aga Khan University

HospitalHospital

CaseCase

17 years old male professional basketball 17 years old male professional basketball player with no known past medical history player with no known past medical history collapses on the playing floor during collapses on the playing floor during practice and subsequently arrests. He had practice and subsequently arrests. He had been having some exertional dyspnea for a been having some exertional dyspnea for a few months prior to this incident but it did few months prior to this incident but it did not affect his activity level. He was told not affect his activity level. He was told growing up that he had a “heart murmur” growing up that he had a “heart murmur” that was never formally investigated. He that was never formally investigated. He was taking no medications, and there was was taking no medications, and there was no family history of cardiac disease in his no family history of cardiac disease in his family. An autopsy later revealed that the family. An autopsy later revealed that the patient had hypertrophic cardiomyopathy. patient had hypertrophic cardiomyopathy.

Background Background

Hypertrophic cardiomyopathy is a genetic Hypertrophic cardiomyopathy is a genetic disorder that is typically inherited in an disorder that is typically inherited in an autosomal dominant fashion with variable autosomal dominant fashion with variable penetrance and variable expressivity penetrance and variable expressivity

The disease has complex symptomatology The disease has complex symptomatology and potentially devastating consequences and potentially devastating consequences for patients and their familiesfor patients and their families

HCM is the leading cause of sudden HCM is the leading cause of sudden cardiac death in preadolescent and cardiac death in preadolescent and adolescent childrenadolescent children

The hallmark of the disorder is The hallmark of the disorder is myocardial hypertrophy that is myocardial hypertrophy that is inappropriate, often asymmetrical and inappropriate, often asymmetrical and occurs in the absence of an obvious occurs in the absence of an obvious inciting hypertrophy stimulusinciting hypertrophy stimulus

This hypertrophy can occur in any This hypertrophy can occur in any region of the left ventricle but region of the left ventricle but frequently involves the IVS, which frequently involves the IVS, which results in an obstruction of flow through results in an obstruction of flow through the LVOTthe LVOT


Prevalence of HCM: Prevalence of HCM: 0.05-0.2% of the population 0.05-0.2% of the population

This occurrence is higher than previously thought, This occurrence is higher than previously thought, suggesting a large number of affected but undiagnosed suggesting a large number of affected but undiagnosed people people

Morphologic evidence of disease is found by Morphologic evidence of disease is found by echocardiography in approximately 25% of first-echocardiography in approximately 25% of first-degree relatives of patients with HCMdegree relatives of patients with HCM

Men and African-Americans affected by almost Men and African-Americans affected by almost 2:1 ratio over women and Caucasians 2:1 ratio over women and Caucasians

Global disease with most cases reported from Global disease with most cases reported from USA, Canada, Western Europe, Israel, & Asia USA, Canada, Western Europe, Israel, & Asia


Maron BJ et al. Circulation. Aug 15 1995;92(4):785-9

Historical Perspective Historical Perspective

HCM was initially described by Teare in HCM was initially described by Teare in 1958 1958

Found massive hypertrophy of ventricular septum Found massive hypertrophy of ventricular septum in small cohort of young patients who died in small cohort of young patients who died suddenly suddenly

Braunwald was the first to diagnose HCM Braunwald was the first to diagnose HCM clinically in the 1960s clinically in the 1960s

Many names for the disease Many names for the disease Idiopathic hypertrophic subaortic stenosis (IHSS)Idiopathic hypertrophic subaortic stenosis (IHSS) Muscle subaortic stenosis Muscle subaortic stenosis Hypertrophic obstructive cardiomyopathy (HOCM)Hypertrophic obstructive cardiomyopathy (HOCM)

Genetic Basis of HCM Genetic Basis of HCM

Autosomal dominant Autosomal dominant inheritance pattern inheritance pattern

>450 mutations in 13 >450 mutations in 13 cardiac sarcomere & cardiac sarcomere & myofilament (myofilament (myosin heavy myosin heavy chain, actin, tropomyosin, chain, actin, tropomyosin, and titin) and titin) related genes related genes identifiedidentified

Genotype specific risks for Genotype specific risks for mortality and degree of mortality and degree of hypertrophyhypertrophy

Genetic basis of ventricular Genetic basis of ventricular hypertrophy does not hypertrophy does not directly correlate with directly correlate with prognostic risk stratificationprognostic risk stratification

Alcalai et al. J Cardiovasc Electrophysiol 2008;19:104-110.

Genetics of HCMGenetics of HCM

Alcalai et al. J Cardiovasc Electrophysiol 2008;19:105.

PatternsPatterns

Pathophysiology of HCMPathophysiology of HCM

The pathophysiology of HCM involves The pathophysiology of HCM involves 4 interrelated processes:4 interrelated processes: Left ventricular outflow Left ventricular outflow

obstruction obstruction Diastolic dysfunction Diastolic dysfunction Myocardial ischemia Myocardial ischemia Mitral regurgitation Mitral regurgitation

LV Outflow Obstruction in HCMLV Outflow Obstruction in HCM

Long-standing LV outflow obstruction Long-standing LV outflow obstruction is a major determinant for heart failure is a major determinant for heart failure symptoms and death in HCM patients symptoms and death in HCM patients

Subaortic outflow obstruction is Subaortic outflow obstruction is caused by systolic anterior motion caused by systolic anterior motion (SAM) of the mitral valve – leaflets (SAM) of the mitral valve – leaflets move toward the septummove toward the septum

Explanations for the SAM of the mitral valve Explanations for the SAM of the mitral valve

1.1. Mitral valve is pulled against the septum by Mitral valve is pulled against the septum by contraction of the papillary muscles, which contraction of the papillary muscles, which occurs because of the valve's abnormal occurs because of the valve's abnormal location and septal hypertrophy altering the location and septal hypertrophy altering the orientation of the papillary musclesorientation of the papillary muscles

2.2. Mitral valve is pushed against the septum Mitral valve is pushed against the septum because of its abnormal position in the because of its abnormal position in the outflow tractoutflow tract

3.3. Mitral valve is drawn toward the septum Mitral valve is drawn toward the septum because of the lower pressure that occurs because of the lower pressure that occurs as blood is ejected at high velocity through as blood is ejected at high velocity through a narrowed outflow tract (Venturi effect)a narrowed outflow tract (Venturi effect)


Physiological Consequences of Physiological Consequences of Obstruction Obstruction Elevated intraventricular pressures Elevated intraventricular pressures Prolongation of ventricular relaxation Prolongation of ventricular relaxation Increased myocardial wall stress Increased myocardial wall stress Increased oxygen demand Increased oxygen demand Decrease in forward cardiac output Decrease in forward cardiac output


Maron MS et al. NEJM. 2003;348:295.

Freedom from HCM related deaths Freedom from HCM related deaths


Diastolic Dysfunction Diastolic Dysfunction Contributing factor in 80% of patients Contributing factor in 80% of patients Impaired relaxation Impaired relaxation

High systolic contraction load High systolic contraction load Ventricular contraction/relaxation not Ventricular contraction/relaxation not

uniform uniform Accounts for symptoms of exertional Accounts for symptoms of exertional

dyspneadyspnea Increased filling pressures Increased filling pressures increased increased

pulmonary venous pressure pulmonary venous pressure

Myocardial Ischemia Myocardial Ischemia Often occurs without atherosclerotic coronary Often occurs without atherosclerotic coronary

artery disease artery disease Postulated mechanismsPostulated mechanisms

Abnormally small and partially obliterated Abnormally small and partially obliterated intramural coronary arteries as a result of intramural coronary arteries as a result of hypertrophy hypertrophy

Inadequate number of capillaries for the degree of Inadequate number of capillaries for the degree of LV mass and increased myocardial oxygen LV mass and increased myocardial oxygen consumptionconsumption

Increased filling pressuresIncreased filling pressures Resulting in subendocardial ischemiaResulting in subendocardial ischemia


Mitral Regurgitation Mitral Regurgitation Results from the systolic anterior motion of Results from the systolic anterior motion of

the mitral valvethe mitral valve Variations in leaflet length Variations in leaflet length

(posterior/anterior leaflet length mismatch) (posterior/anterior leaflet length mismatch) – restrict the ability of the posterior leaflet – restrict the ability of the posterior leaflet to follow the anterior leaflet and to coapt to follow the anterior leaflet and to coapt effectively resulting in MReffectively resulting in MR

Severity of MR directly proportional to LV Severity of MR directly proportional to LV outflow obstruction outflow obstruction

Results in symptoms of dyspnea, orthopnea Results in symptoms of dyspnea, orthopnea in HCM patients in HCM patients


Clinical Presentation Clinical Presentation

Dyspnea on exertion (90%), orthopnea, Dyspnea on exertion (90%), orthopnea, PNDPND

Palpitations (PAC, PVC, sinus pauses, AF, A Palpitations (PAC, PVC, sinus pauses, AF, A flutter, SVT and VT)flutter, SVT and VT)

Congestive heart failureCongestive heart failure (2 (2oo to increased to increased filling pressures and myocardial ischemia)filling pressures and myocardial ischemia)

Angina (70-80%) Angina (70-80%) Syncope (20%), Presyncope (50%) Syncope (20%), Presyncope (50%)

Outflow obstruction worsens with increased Outflow obstruction worsens with increased contractility during exertional activities contractility during exertional activities resulting in decrease in cardiac outputresulting in decrease in cardiac output

Secondary to arrhythmiasSecondary to arrhythmias

Sudden cardiac deathSudden cardiac death HCM is most common cause of SCD in HCM is most common cause of SCD in

young people, including athletesyoung people, including athletes Can be the first manifestationCan be the first manifestation Most common cause is arrhythmias esp. Most common cause is arrhythmias esp.

VF either denovo or AF degenerated VF either denovo or AF degenerated into VF 2into VF 2oo accessory pathway accessory pathway

Clinical Presentation Clinical Presentation

Physical Examination Physical Examination

Carotid PulseCarotid Pulse Bifid – Bifid – rises quickly, then declines in midsystole rises quickly, then declines in midsystole

followed by a secondary rise in carotid pulsation followed by a secondary rise in carotid pulsation during late systole during late systole short upstroke & prolonged short upstroke & prolonged systolic ejection systolic ejection

Jugular Venous Pulse Jugular Venous Pulse Prominent Prominent a wavea wave – decreased RV compliance – decreased RV compliance

Apical Impulse Apical Impulse Double apical impulse - forceful left atrial Double apical impulse - forceful left atrial

contraction against a highly noncompliant left contraction against a highly noncompliant left ventricleventricle

Triple apical impulse results from a late systolic Triple apical impulse results from a late systolic bulge that occurs when the heart is almost empty bulge that occurs when the heart is almost empty and is performing near-isometric contractionand is performing near-isometric contraction


Heart SoundsHeart Sounds S1 usually normalS1 usually normal S2 usually split but in severe stenosis – S2 usually split but in severe stenosis –

paradoxically splitparadoxically split S3 indicate heart failureS3 indicate heart failure S4 usually present due to hypertrophyS4 usually present due to hypertrophy

MurmurMurmur Medium-pitch crescendo-decrescendo systolic Medium-pitch crescendo-decrescendo systolic

murmur along LLSB and apex and radiates to murmur along LLSB and apex and radiates to suprasternal notchsuprasternal notch

Dynamic maneuvers Dynamic maneuvers Murmur intensity increases with decreased Murmur intensity increases with decreased

preload (i.e. Valsalva, standing, nitrates, preload (i.e. Valsalva, standing, nitrates, diuretics)diuretics)

Murmur intensity decreases with increased Murmur intensity decreases with increased preload (i.e. squatting, hand grip) preload (i.e. squatting, hand grip)

Holosystolic murmur at the apex and Holosystolic murmur at the apex and axilla of mitral regurgitation is heard in axilla of mitral regurgitation is heard in patients with systolic anterior motion of patients with systolic anterior motion of the mitral valve and significant LV the mitral valve and significant LV outflow gradientsoutflow gradients

Diastolic decrescendo murmur of aortic Diastolic decrescendo murmur of aortic regurgitation is heard in 10% of patients, regurgitation is heard in 10% of patients, although mild aortic regurgitation can be although mild aortic regurgitation can be detected by Doppler echocardiography in detected by Doppler echocardiography in 33% of patients33% of patients


Diagnostic Evaluation Diagnostic Evaluation

ElectrocardiogramElectrocardiogram Echocardiogram Echocardiogram Catheterization Catheterization Cardiac MRCardiac MR

Electrocardiogram in HCMElectrocardiogram in HCM

LVH with nonspecific ST/T wave abnormalitiesLeft or right axis deviation, LAE, Conduction abnormalitiesAbnormal and prominent Q wave in the anterior precordial and lateral limb leadsA fib with preexitation implies poor prognosisFindings on Holter monitoring include APC’s VPC’s, sinus pauses, wandering atrial pacemaker, atrial tachycardia, AF/flutter and nonsustained ventricular tachycardia.

2-D echocardiography is diagnostic for HCM2-D echocardiography is diagnostic for HCM Abnormal systolic anterior leaflet motion of the Abnormal systolic anterior leaflet motion of the

mitral valvemitral valve LV hypertrophyLV hypertrophy Left atrial enlargementLeft atrial enlargement Diastolic dysfunctionDiastolic dysfunction Small ventricular chamber sizeSmall ventricular chamber size Septal hypertrophy with septal to free wall ratio Septal hypertrophy with septal to free wall ratio

greater than 1.4:1 (absolute septal wall thickness greater than 1.4:1 (absolute septal wall thickness >15mm)>15mm)

SAM of anterior and rarely posterior mitral valve SAM of anterior and rarely posterior mitral valve leaflet and mitral regurgitationleaflet and mitral regurgitation

Decreased mid aortic flowDecreased mid aortic flow Partial systolic closure of the aortic valve in mid Partial systolic closure of the aortic valve in mid

systolesystole

Echocardiography in HCMEchocardiography in HCM

Useful when echocardiography is questionable, Useful when echocardiography is questionable, particularly with apical hypertrophyparticularly with apical hypertrophy

Cines loops typically show obstruction and velocity Cines loops typically show obstruction and velocity mapping is useful in the assessment of peak mapping is useful in the assessment of peak velocitiesvelocities

SAM of the mitral valve is clearly seen on cardiac SAM of the mitral valve is clearly seen on cardiac MRIMRI

Improvement in obstruction after septal ablation or Improvement in obstruction after septal ablation or myomectomy can be demonstrated, as can the myomectomy can be demonstrated, as can the location and size of the associated infarction, which location and size of the associated infarction, which are useful for planning repeat proceduresare useful for planning repeat procedures

Cardiac MRI tagging identifies abnormal patterns of Cardiac MRI tagging identifies abnormal patterns of strain, shear, and torsion in cases of HCM, strain, shear, and torsion in cases of HCM, demonstrating significant dysfunction in demonstrating significant dysfunction in hypertrophic areas of the ventriclehypertrophic areas of the ventricle

Cardiac MRI in HCMCardiac MRI in HCM

Gadolinium contrast cardiac MRI - differentiating Gadolinium contrast cardiac MRI - differentiating HCM from other causes of cardiac hypertrophy and HCM from other causes of cardiac hypertrophy and other types of cardiomyopathy such as, amyloidosis, other types of cardiomyopathy such as, amyloidosis, athletic heart, and Fabry’s diseaseathletic heart, and Fabry’s disease

Late gadolinium enhancement occurring in HCM Late gadolinium enhancement occurring in HCM represents myocardial fibrosisrepresents myocardial fibrosis The greater the degree of late gadolinium enhancement, the The greater the degree of late gadolinium enhancement, the

more likely that the particular HCM patient has 2 or more more likely that the particular HCM patient has 2 or more risk factors for sudden deathrisk factors for sudden death

More likely the patient has or will develop progression of More likely the patient has or will develop progression of ventricular dilation toward heart failure, thereby indicating ventricular dilation toward heart failure, thereby indicating a poorer prognosisa poorer prognosis

Most patients with HCM have no gadolinium Most patients with HCM have no gadolinium enhancementenhancement Common benign pattern is 2 stripes running along the Common benign pattern is 2 stripes running along the

junction of the right ventricle insertion into the left ventriclejunction of the right ventricle insertion into the left ventricle

Cardiac MRI in HCMCardiac MRI in HCM

Apical HCM by Echo & CMRApical HCM by Echo & CMR

•64 female with CP & palpitation•ECG – extensive T wave inversion•Echo – akinetic apex & diastolic dysfunction•Cine CMR – confirmed clinical suspicion of apical HCM

High risk HCMHigh risk HCM

•33 male with HCM and family history of sudden death•Cine CMR shows HCM with ASH•After gadolinium extensive late enhancement•Patient was offered an ICD

Diagnostic cardiac catheterization is useful to Diagnostic cardiac catheterization is useful to determine the degree of LVOT obstruction, cardiac determine the degree of LVOT obstruction, cardiac hemodynamics, the diastolic characteristics of the hemodynamics, the diastolic characteristics of the left ventricle, LV anatomy and coronary anatomyleft ventricle, LV anatomy and coronary anatomy

Reserved for situations when invasive modalities of Reserved for situations when invasive modalities of therapy, such as a pacemaker or surgery, are being therapy, such as a pacemaker or surgery, are being consideredconsidered

Therapeutic cardiac catheterization interventions, Therapeutic cardiac catheterization interventions, include transcatheter septal alcohol ablationinclude transcatheter septal alcohol ablation

The arterial pressure tracing found on cardiac The arterial pressure tracing found on cardiac catheterization may demonstrate a "spike and catheterization may demonstrate a "spike and dome" configurationdome" configuration

Cardiac Catheterization Cardiac Catheterization


Approximately one fourth of patients Approximately one fourth of patients demonstrate pulmonary hypertension - demonstrate pulmonary hypertension - usually mildusually mild

Enhancing of LVOT gradient in post PVC Enhancing of LVOT gradient in post PVC Results in characteristic change recorded on Results in characteristic change recorded on

arterial pressure tracing - exhibits a pulse arterial pressure tracing - exhibits a pulse pressure that fails to increase as expected or pressure that fails to increase as expected or actually decreases (the so-called Brockenbrough-actually decreases (the so-called Brockenbrough-Braunwald phenomenon)Braunwald phenomenon)

One of the more reliable signs of dynamic One of the more reliable signs of dynamic obstruction of the LVOT, intensity of murmur also obstruction of the LVOT, intensity of murmur also increasedincreased


• LV gram shows hypertrophied LV• MR secondary to SAM of mitral valve• The LV cavity is often small and systolic ejection is typically vigorous, resulting in virtual obliteration of the ventricular cavity at end systole• In patients with apical involvement, the extensive hypertrophy may convey a spade-like configuration to the left ventricular angiogram

Disease Progression in HCMDisease Progression in HCM

ACC Consensus Document. J Am Coll Cardiol. 2003;42(9):1693.

Sudden Cardiac Death in HCM Sudden Cardiac Death in HCM

Most frequent in Most frequent in young adults <30-35 young adults <30-35 years oldyears old

Primary VF/VT Primary VF/VT Tend to die during or Tend to die during or

just following just following vigorous physical vigorous physical activity activity

Often is 1Often is 1stst clinical clinical manifestation of manifestation of disease disease

HCM is most common HCM is most common cause of SCD among cause of SCD among young competitive young competitive athletes athletes

J Am Coll Cardiol. 2003;42(9):1693.

SCD in Competitive Athletes SCD in Competitive Athletes

Maron B. Atlas of Heart Diseases. 1996

Natural History of HCM Natural History of HCM

Heart Failure Heart Failure Only 10-15% progress Only 10-15% progress

to NYHA III-IV to NYHA III-IV Only 3% will become Only 3% will become

truly end-stage with truly end-stage with systolic dysfunction systolic dysfunction

Endocarditis Endocarditis 4-5% of HCM patients 4-5% of HCM patients Usually mitral valve Usually mitral valve

affected affected

Atrial Fibrillation Atrial Fibrillation Prevalent in up to Prevalent in up to

30% of older patients30% of older patients Dependent on atrial Dependent on atrial

kick – CO decreases kick – CO decreases by 40% if AF present by 40% if AF present

Autonomic Autonomic Dysfunction Dysfunction 25% of HCM patients 25% of HCM patients Associated with poor Associated with poor

prognosis prognosis

Influence of Gender & Race Influence of Gender & Race

Women often remain under Women often remain under diagnosed and are clinical diagnosed and are clinical recognized after they develop more recognized after they develop more pronounced symptomspronounced symptoms11

HCM clinically under recognized in HCM clinically under recognized in African-Americans African-Americans Most athletes with SCD due to HCM are Most athletes with SCD due to HCM are

undiagnosed African-Americansundiagnosed African-Americans22

1 Olivotto I et al. J Am Coll Cardiol 2005;46:480. 2 Maron BJ et al. J Am Coll Cardiol 2003;41:974.

Treatment of HCM Treatment of HCM

Medical therapy Medical therapy Device therapy Device therapy Surgical septal myomectomy Surgical septal myomectomy Alcohol septal ablationAlcohol septal ablation

ACC Consensus Document. J Am Coll Cardiol. 2003;42(9):1693.

MedicalMedical Therapy Therapy

Beta-blockersBeta-blockers Increase ventricular diastolic filling/relaxation Increase ventricular diastolic filling/relaxation Decrease myocardial oxygen consumption Decrease myocardial oxygen consumption Have not been shown to reduce the incidence Have not been shown to reduce the incidence

of SCD of SCD Verapamil Verapamil

Augments ventricular diastolic Augments ventricular diastolic filling/relaxation filling/relaxation

Disopyramide Disopyramide Used in combination with beta-blocker Used in combination with beta-blocker Negative inotrope Negative inotrope

Diuretics Diuretics

Dual-Chamber Pacing Dual-Chamber Pacing

Proposed benefit: Proposed benefit: Pacing the RV apex will decrease the outflow tract Pacing the RV apex will decrease the outflow tract

gradient by decreasing projection of basal septum gradient by decreasing projection of basal septum into LVOTinto LVOT

Several RCTs have found that the Several RCTs have found that the improvement in subjective measures provided improvement in subjective measures provided by dual-chamber pacing is likely a placebo by dual-chamber pacing is likely a placebo effect effect

Objective measures such as exercise capacity Objective measures such as exercise capacity and oxygen consumption are not improved and oxygen consumption are not improved

No correlation has been found between No correlation has been found between pacing and reduction of LVOT gradient pacing and reduction of LVOT gradient

Surgical Septal MyectomySurgical Septal Myectomy

Nishimura RA et al. NEJM. 2004. 350(13):1320.

J Am Coll Cardiol 1999;34(1):191-6.

Alcohol Septal Ablation Alcohol Septal Ablation


Before After

Pre Alcohol Septal Pre Alcohol Septal AblationAblation

Post Alcohol Septal Post Alcohol Septal AblationAblation


Successful short-term outcomesSuccessful short-term outcomes LVOT gradient reduced from a mean of 60-70 LVOT gradient reduced from a mean of 60-70

mmHg to <20 mmHg mmHg to <20 mmHg Symptomatic improvements, increased exercise Symptomatic improvements, increased exercise

tolerance tolerance Long-term data not available yet Long-term data not available yet Complications Complications

Complete heart blockComplete heart block Large myocardial infarctionLarge myocardial infarction

No randomized efficacy trials yet for alcohol No randomized efficacy trials yet for alcohol septal ablation vs. surgical myectomy septal ablation vs. surgical myectomy

Circulation. 2008; 18(2): 131-9.

Overall survival: 93.5% at 2 yrs, 88% at 4 yrs

Efficacy of Therapeutic Efficacy of Therapeutic StrategiesStrategies

Nishimura et al. NEJM. 2004. 350(13):1323.

CoilCoil Embolization Embolization

Case report of 20 patients Case report of 20 patients with drug-refractory with drug-refractory HCM HCM

Occlude septal perforator Occlude septal perforator branches branches

NYHA functional class NYHA functional class and peak oxygen and peak oxygen consumption improved at consumption improved at 6 months 6 months

Significant reduction in Significant reduction in septum thickness by echo septum thickness by echo

European Heart Journal 2008;29:350.

Implantable Cardioverter Implantable Cardioverter

Defibrillators in HCMDefibrillators in HCM Primary & Secondary Primary & Secondary

Prevention Prevention

Maron BJ et al. NEJM 2000;342:365-73.

Appropriate discharges Appropriate discharges in 23% of patients in 23% of patients

Rate of appropriate Rate of appropriate discharges of 7% per discharges of 7% per year year

Of 21 patients for which Of 21 patients for which intracardiac intracardiac electrograms were electrograms were available, 10 shocks for available, 10 shocks for VT, 9 shocks for VFVT, 9 shocks for VF

Suggested role for ICDs Suggested role for ICDs in primary & secondary in primary & secondary prevention of SCDprevention of SCD

Risk Stratification – ICDs Risk Stratification – ICDs

Primary Prevention Risk Factors for Primary Prevention Risk Factors for SCD SCD Premature HCM-related sudden death Premature HCM-related sudden death

in more than 1 relative in more than 1 relative History of unexplained syncope History of unexplained syncope Multiple or prolonged NSVT on Holter Multiple or prolonged NSVT on Holter Hypotensive blood pressure response to Hypotensive blood pressure response to

exercise exercise Massive LVH Massive LVH How many risk factors warrant ICD

placement?

Multicenter registry Multicenter registry study with 506 pts study with 506 pts from 1986-2003 from 1986-2003

Average age 41 years Average age 41 years oldold

35% pts - primary 35% pts - primary prevention received prevention received ICDs had 1 risk factor ICDs had 1 risk factor

Primary Outcome: Primary Outcome: appropriate ICD appropriate ICD interventions interventions terminating VF/VT terminating VF/VT

J Cardiovasc Electrophysiol 2008;19(10).

J Am Coll Cardiol. 2008;51(10):1033-9.

3500 asymptomatic elite 3500 asymptomatic elite athletes (75% male), mean athletes (75% male), mean age 20.5 +/- 5.8 years, no age 20.5 +/- 5.8 years, no family hx of HCM family hx of HCM

12-lead ECG, 2D-Echo 12-lead ECG, 2D-Echo 53 athletes (1.5%) had 53 athletes (1.5%) had

LVH LVH 3 athletes (0.08%) had 3 athletes (0.08%) had

ECG and echo features of ECG and echo features of HCMHCM

HCM vs. Athlete’s Heart HCM vs. Athlete’s Heart

Circulation 1995;91.

Future Directions Future Directions

Identification of additional causative Identification of additional causative mutations mutations

Risk stratification tools Risk stratification tools Determining more precise indications for Determining more precise indications for

ICDs ICDs Defining most appropriate role for alcohol Defining most appropriate role for alcohol

septal ablation septal ablation ?Gene therapy ?Gene therapy

Thank You!Thank You!

hypertrophic cardiomyopathy

Documents

families hcm

hcm men

background prevalence

outflow tract3

historical perspective

hcm related deathsmaron

mitral valve1

septal hypertrophy