high cardiac output athletes the role of ventricular ... · of cv adaptation to exercise. s...

Aaron L. Baggish MD, F.A.C.C., F.A.C.S.M. Institut des Sciences Du Sport l’Université de Lausanne, (ISSUL) Associate Professor of Medicine, Harvard Medical School Director, Cardiovascular Performance Program Massachusetts General Hospital Boston, MA

High Cardiac Output Athletes The Role of Ventricular Remodeling

Conflicts:NoneAthleticAffiliations:FundingSources:

–  NationalInstitutesofHealth–  AmericanHeartAssociation–  AmericanSocietyofEchocardiography–  DepartmentofDefense–  NationalFootballLeaguePlayer’sAssociation

Cardiac Plasticity: Remodeling

Classic concept of LV remodeling……

Aortic Regurgitation

Aortic Stenosis

Volume Challenge Pressure ChallengeChamber Dilation

Wall Thickening

Endurance Activities

Sustained ↑ CO •  4 to 5 times rest•  ↑ ↑ ↑ HR & ↑ SV•  Vasodilation

Strength Activities

Repetitive↑ SBP •  Systolic BP > 300 mmHg•  Skeletal Mus. Contraction•  Vasoconstriction

Pressure Challenge

Cardiac Remodeling: Physiology

Volume Challenge

Observation: Basketball Players are Tall

Historical Data: Limitations

Observation: Basketball Players are Tall

Explanation ?

Tall people self-select for basketball

Basketball makes people grow tall

Historical Data: Limitations

Historical Data: Causality?

Does exercise cause heart enlargement or do people born with “big hearts” simply self select for sport?

Acute Training Intensification Extended Training

ExperienceBaseline

June August October September November July

Pre-StudyPeriod

(48days)

StudyPeriod(90days)

Baseline Conditioning

Study ExerciseExposure

#1 - ECG, Blood, Echo, IHGT, Tono.

CPET, MRI, PET

The Harvard Athlete Initiative (HAI)

A platform for longitudinal, repeated measures studies of CV adaptation to exercise.

Multiyear Cycles

Alumni Follow

-up

#2 - ECG, Blood, Echo, IHGT, Tono.

CPET, MRI, PET

December

Jeremy Lin - NBA

Ryan Fitzpatrick - NFL

Esther Lofgren - USA

Andrew Campbell - USA

THE HARVARD ATHLETEINITIATIVE 2005-2018

Strength Athletes Endurance Athletes

HAI: Sport Specificity of EICR

June August October September November July

Pre-StudyPeriod

(48days)

StudyPeriod(90days)

Do these hearts change and if so do they do so differently?

Correlation:∆LVMassvs.∆LVEDV

Correlation:∆LVMassvs.∆IVS+PWT

Endurance

Endurance

Strength

Strength

* *

∆IVS

+PWT(m

m/m

2 )

∆LVE

DV(m

l/m

2 )

∆=14±4g/m2∆=16±5g/m2

J Appl Physiol 2008;104:1121

HAI: Sport Specific of EICR

Dilation

Thickness

pre post pre post100

110

120

130

140

150g/m2

Endurance Strength

∆LeftVentricularMass

(g/m

2 )

* *ROWING ADAPTATION #1:

“LV DILATION”Four chamber dilation

Large EDV potentiates Large SV“Start Big / Pump Big”


Levine, Baggish, et al. JACC 2015

Volume Load

Pr

essu

re L

oad

Endurance Sport Physiology

High CO

Incr

easi

ng P

ress

ure

Load

The Role of the Heart in Sport Performance

Trained Athlete

VO2 = CO x Δ(AO2-VO2)

VO2 = SV x HR

Beck et al. J Appl Physiol. 2006

LV Challenges: 1.) Filling 2.) Ejecting 3.) Energetics


High CO

Incr

easi

ng P

ress

ure

Load

156

142

Heart Rate ~ Work “Tightly Coupled”....All Endurance Sports


High CO

Incr

easi

ng P

ress

ure

Load

14

12

CO (HR x SV)~ Work “Tightly Coupled”....All Endurance Sports


High CO

Incr

easi

ng P

ress

ure

Load

140é

110ê

Arterial Blood Pressure Is Endurance Sport Specific

High CO

Incr

easi

ng P

ress

ure

Load


MAP=110

DBP =70

SBP =190

MAP=140

SBP =300

DBP =60

* * * *

Rowing requires high CO in the face of pressure

10 Sec. BPTracings

Endurance Remodeling Variants

Wasfy et al. JASE 2015

ROWING ADAPTATION #2:“LV WALL THICKENING”

Eccentric LV HypertrophyBalance Chamber Dilation & Wall Thickening

“Pump Big at Minimal Cost”

Endurance: LV Filling

Having a Big Heart at Rest Big Heart During Exercise≠

Heart Rate 60SEP = 300 ms / DFP = 700 ms

Heart Rate 160SEP = 200 ms / DFP = 175 ms

FUNDAMENTAL CHALLENGE FOR THE ENDURANDCE HEART...

Filling NOT PumpingNo Matter How Big You Are,

If you can’t fill, you can’t pump

LVHypertrophy&DiastolicFunction

J Appl Physiol 2008;104:1121

∆LateralE’(cm/s)

∆LVMass(g/m2)

r2=0.90

r2=0.79

Compliant Heart

Stiff Heart

pre post pre post100

110

120

130

140

150g/m2

Endurance Strength

∆LeftVentricularMass

(g/m

2 )



ROWING ADAPTATION #3:“ENHANCED LV RELAXATION”Fiber Speed (Intrinsic Myocyte)

Elastic Recoil“Strokers Become Suckers”

Endurance: Myocardial Energetics

Big Hearts = Inefficient Hearts....?

Wasfy et a. JACC Imaging 2018

C-11 Acetate PET

ROWING ADAPTATION #4:“PRESERVED ENERGETICS”More work, same energy

Substrate SwitchingHoly Grail of the Athlete’s Heart??

Endurance: Remodeling Time Line?

Nothing Happens Overnight.... Discrete Steps?

ROWING ADAPTATION #5:“STEPWISE PROCESS”

Dilation before Thickening& Lengthening

Vascular Volume Expansion Key

Endurance: Remodeling vs. Skill Level

ROWING ADAPTATION #6:COMPETITION LEVEL MATTERSGenetics (Baseline & Plasticity)

Chronic Training Stimulus DoseWhat You See Depends on Who You Study

Key CV Controversies

SO FAR SO GOOD.....

BUT, Can you get too much of a good thing??

Athlete’s Heart: The Beginnings…

We have seen that a great increase in size and strength is demanded of the heart and it may easily happen that it is called upon for more work than it is able to do and that instead of establishing a compensatory hypertrophy it becomes diluted and weakened. A "broken-winded " athlete is probably one with a dilated, flabby heart. -Eugene Darling 1899

Harvard Athlete Initiative

Cardiomyopathy

BL

ML

AL

BS

MS

AS

0.6±0.8*

3.5±1.8†

4.4±3.2†

1.0±0.8*

2.5±1.7†

3.9±2.4†

(-2to2) (2to4) (4to6) (>6)(<-2)

BS BL

MS ML

AS AL

LV Systolic Strain Changes with Rowing Training (n=20)

ASA

L

PI

S

8.3± 9.4*

7.3± 8.4*

8.8± 10.2*

8.4± 10.1*

9.1± 10.7*

9.8± 9.3*(-2to2) (2to4) (4to6) (>6)(<-2)

A

L

P

AS

S

I

ASA

L

PI

S

-3.3± 2.7* 3.4± 2.2†

3.3± 2.4†

3.2± 2.5†3.0± 3.6*

-3.6± 1.7†

(-2to2) (2to4) (4to6) (>6)(<-2)

A

L

P

AS

S

I

Longitudinal ~ ñ20-25% Radial ~ ñ50-60% Circumferential ~ ê20-25%

Normal to Supranormal Strain….Focal Septal Dysfunction Fatigue??

Cardiomyopathy

TheVentricularInterdependenceofPhysiologicRemodeling

Am J Physiol Heart Circ Physiol 2008;295:1109

Cardiomyopathy

Whyte et al. JAP 2011

LaGerche et al. EHJ 2011

Cardiomyopathy

•  40 trained (>10 h of intense training / week) athletes

•  Competitive, top 25% finish recent endurance event

•  No cardiac symptoms or traditional risk factors

•  No inducible ischemia on stress echo

•  MRI/echo/biochem. At 3 time points (pre-finish-6 to 11 d)

Cardiomyopathy

Cardiomyopathy

Preliminary data suggests that a small minority of chronic endurance athletes may develop a

fibrotic cardiomyopathy…a phenotype of uncertain clinical relevance that deserves our attention and further outcomes-based study

Exercise Cardiomyopathy ?

Chronic Extreme Volume & Intensity

Training / RecoveryMismatch

Host Susceptibility(Genetics)

Secondary Process(Drugs, Infection, Disease)

+

+

+

“The PerfectStorm”

A Theoretical Pathogenic

Cascade

Summary

Key Cardiac Adaptations in Rowers:

1.) Bi-ventricular growth (Ecc.-LVH)

2.) Enhanced filling capacity (High HR)

3.) Preserved energetics

4.) Phasic remodeling process

5.) Competition level-specific phenotype

6.) Fatigable... Injury prone with overuse??

Acknowledgements

MGH

G. William Dec, MD Jason Elinoff, MD Laurie Farrell, RN Adolph Hutter, MD Jonathan Kim, MD Greg Lewis, MD

Jane Marshall, RDCS Carlene McClanahan, RDCS

Deb Mcdonald Ellie Morris, RDCS

Jennifer Neary, RDCS Michael Picard, MD

Anthony Rosenzweig, MD Thomas Wang, MD Meagan Wasfy, MD Rory Weiner, MD

Arthur Weyman, MD Malissa Wood, MD

Harvard University

Brant BerkstresserArthur Boland, MD

Charles ButtsWilliam ManningTimothy MurphyElizabeth O’Leary

Harry ParkerBob Scalise

Francis Wang, MDResearch Support

American Heart AssociationAmerican Society of Echocardiography

American College of Sports MedicineCIMIT

Thank You !

high cardiac output athletes the role of ventricular ... · of cv adaptation to exercise. s...

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