...

Nessun titolo diapositiva

by user

on
Category:

genetics

27

views

Report

Comments

Transcript

Nessun titolo diapositiva
Cardiac Adaptation to Exercise
chronic
Morphological
Functional
•Myocardial
•Neural
•Vascular
Chronic Cardiac
Adaptation to Exercise
Morphological
Myocardial hypertrophy
Coronaries
CRMS
Chronic Cardiac
Adaptation to Exercise
Morphological
Myocardial hypertrophy
•Eccentric
•Concentric
Coronaries
CRMS
Hypertrophia-Hyperplasia
• Hyperplasia constitutes an increase in the number of
cells in an organ or tissue, which may then have
increased volume.
• Hypertrophy refers to an increase in the size of cells
and, with such change, an increase in the size of the
organ
Myocardial hypertrophy
pressure overload
Due to physical stimuli
volume overload
Due to hormonal chemical stimuli
CRMS
Factors promoting Cardiac hypertrophy
Mechanical Force
CRMS
Development of Myocardial
Hypertrophy
Pressure Overload
Volume Overload
Increased parietal
systolic stress
Increased parietal
diastolic stress
Addition of sarcomer
in parallel
Addition of sarcomer
in series
Increase wall thickness
Increase chamber size
Concentric Hypertrophy Collagen
Eccentric Hypertrophy
CRMS
Effects of pressure/volume overload
on cardiac structure and function
Exercise (Isometric-Isotonic)
Overload Volume/pressure
Adeguate
Capillary density
Myocite
Hypertrophy
Cardiac remodelling
Increase contrattility
Athletic Heart
CRMS
Effects of Training on Left Ventricle
Adaptation of the Heart to
Exercise Training
Adaptation of the Heart to Exercise
Normal
Concentric
Eccentric
Calculation of Left Ventricle Mass
LVM(gr) =0,80x1,05x (IVS+PWT+LVID)3-LVID
CRMS
3
Anatomical Section Through
the Short Axis of Left Ventricle
Short Axis View of Left Ventricle
in Normal Subject
Short Axis View of Left Ventricle
in Athlete
Pathological Hypertrophy
Hypertrophy Modulating
Factors
1. Age
2. Gender
3. Type of stimulus
4. Genetic heritage
CRMS
Hypertrophy Modulating
Factors
• Age
Left Ventricular Mass in young
athletes ( soccer players): a cross
echocardiographic study
Giorgio Galanti M.D, Paolo Manetti M.D.,
Maria Concetta Vono M.D., Loira Toncelli
M.D., Paola Zilli M.D., Carlo Rostagno M.D.,
Vieri Boddi M.Sc.*, Natale Villari
M.D**,Roberto Salti M.D.
CRMS
• Purpose - Regular exercising induces changes in
left ventricular mass (LVM). While its effects in adults
are well known, few data are so far available on those
in adolescents.
• Methods - group of 127 young male soccer players
(aged 13.6±2.1 yr., mean ± standard deviation) was
studied. They had been regularly playing soccer since
they were six years old. Players were age-matched
with 70 male sedentary adolescents. LVM was
detected with echocardiography and body
composition with bioelectrical impedance analysis.
Pubertal stadiation was evaluated with the Tanner
method and skeletal maturation with hand x-ray.
Results - Skeletal age, Tanner maturation and weight were
comparable in the two groups, while height (p=0.002), fat-free mass
(FFM, p<0.0005) and cellular body mass (p=0.002) were higher in
athletes. Players showed increased LVM as compared with controls
(159±49 vs. 137±42 g, p=0.002; confirmed by measures of LVM/body
surface area: 97±19 g/m2 vs. 87±17 g/m2, p<0.0005, respectively).
Starting from similar values, LVM progressively increased more in
players than in controls after 12 yr. (Tanner 2), reaching statistical
significance at 15.4 yr. (Tanner 5). In both athletes and controls LVM
was directly correlated with all the anthropometric and
cardiovascular parameters examined (p<0.0005). At multivariate
analysis LVM was significantly correlated with skeletal age (b=8.54),
height (b=1.77) in athletes, and with skeletal age (b=4.83) and FFM
(b=1.83) in controls.
Conclusions
• Our data suggest that exercise induces a
physiological left ventricular
hypertrophy in sportive population.
• This hypertrophy becomes evident after
sexual maturation was achieved.
Hypertrophy Modulating
Factors
Type of stimulus
CRMS
Hypertrophy Modulating
Factors
Circulation Reasearch 2001
Hypertrophy Modulating
Factors
Genetic Heritage
Studied Subjets
Allelic Frequency Analysis
•42 elite soccer male players
(from 17 to 31 years old)
•45 age matched healthy
male controls
All were studied with echocardiography
and DNA analysis
G.Galanti et al. MSSE Nov:2000
Correlation between Left
Ventricular Mass (LVM)
and I/D Polimorphysm
Genotype
DD + ID
II
Athletes with
increased LVM
Athletes without
increased LVM
14
5
0
3
p<0,05
G.Galanti et al. MSSE Nov:2000
CONCLUSIONS
• Increase of left ventricular mass is correlated
with I/D polimorphism: The DD athletes had
shown an increase while the II athletes had a
reduction.
• Increase of left ventricular mass is not
correlated with A/C polimorphism:
CRMS
G.Galanti et al. MSSE Nov:2000
La scelta dello sport è
geneticamente determinata?
Association of angiotensin-converting enzyme gene I/D
polymorphism with change in left ventricular mass in
response to physical training
Montgomery H, Clarkson P et al
Circulation 1997, 96: 741-747)
CRMS
Soggetti Studiati
I soggetti studiati comprendevano
136 atleti allenati (età media 24±3.5
anni)
tra
i
quali
121
erano
calciatori (85 maschi, 36 femmine)
e 15 ciclisti (maschi), confrontati
con
155
controlli,
sedentari,
comparabili per sesso ed età.
CRMS
Risultati
frequenza allelica
La distribuzione del genotipo
è risultata in accordo con
l'equilibrio di Hardy-Weinberg
e
la
frequenza
allelica
è
risultata comparabile nei due
gruppi.
Non sono state evidenziate
differenze
significative
comparando la distribuzione
dei genotipi nei vari tipi di
sport.
CRMS
Athlete’s Heart
Distinguishing normal from abnormal
•
•
•
•
Adeguate Hypertrophy
Normal Systolic Function
Normal Diastolic Function
Reversibility
CRMS
Athlete’s Heart
Distinguishing normal from abnormal
•
•
•
•
Adeguate Hypertrophy
Normal Systolic Function
Normal Diastolic Function
Reversibility
CRMS
Types of Myocardial
Hypertrophy
Normal
Adeguate
Adeguate
NonAdeguate
Variability of wall thickness in
elite athletes
N° Athl
Wall Thickness mm
Pelliccia.NEJM.1991
Athlete’s Heart
Distinguishing normal from abnormal
•
•
•
•
Adeguate Hypertrophy
Normal Systolic Function
Normal Diastolic Function
Reversibility
CRMS
Exercise Echocardiography
Modifications during Exercise
Echocardiography
1. Increse Ejection fraction
2. Decreased Left Systolic
Ventricular Volume
3. No significant modifications of
Wall Stress
CRMS
Athlete’s Heart
Distinguishing normal from abnormal
•
•
•
•
Adeguate Hypertrophy
Normal Systolic Function
Normal Diastolic Function
Reversibility
CRMS
DIASTOLIC FUNCTION IN
ATHLETES
LVM gr/m2
IVR msec
DT msec
Ep cm/sec
Ap cm/sec
ATHLETES
208±28*
69±12*
171±72
84±12*
41±8*
CONTROLS
112±21
76±11
203±31
85±19
56±15
Galanti et al, Angiology 1992 4:315-20
Athlete’s Heart
Distinguishing normal from abnormal
•
•
•
•
Adeguate Hypertrophy
Normal Systolic Function
Normal Diastolic Function
Reversibility
CRMS
Regression of Athlete’s
Hypertrophy
G.Galanti et al. Cardiologia 1989
Cardiac Adaptation to Exercise
chronic
Morphological
Myocardial hypertrophy
•Eccentric
•Concentric
Coronaries
CRMS
Coronary Arteries
Left Coronary in Athlete
Rigth Coronary in Athlete
Cardiac Adaptation to Exercise
chronic
Functional
Heart Rate
Cardiovascular Response to
Acute Exercise in trained subjects
H.R. b/min
Cycloergometer
Recovery
Fly UP