Jae Hyung Park, MD Joon Koo Han, MD
Yang Mm Man Chung
#{149} #{149}
Imaging
MR To assess
the capability
resonance
(MR)
H
to define
in 20 patients cardiomyopathy
and in five healthy volunteers. Among the 20 patients, 13 were sified
as having
asymmetric
clas-
septal
hypertrophy and seven as having apical hypertrophy. The mean myocardial thickness in the four-chamber view obtained in end diastole in asymmetric septal hypertrophy was 23.5 mm ± 6.8 (mean ± standard deviation) in the basal septum; the ratio of septal to posterolateral wall thickness was 2.05 ± 0.44 (P < 05); those values were 10.4 mm ± 2.7 and 1.01 ± 0.19,
respectively,
unteers.
The
in five
mean
healthy
myocardial
vol-
thick-
ness
in apical hypertrophy was 25.3 mm ± 4.1 in the apex, and the ratio was 2.21 ± 0.51 (P < .05); these values were 9.6 mm ± 1.5 and 0.95 ± 0.17,
respectively, in five healthy volunteers. Three different subtypes of hypertrophic cardiomyopathy-resting obstructive (n = 5), latent obstructive (n = 3), and nonobstructive (n = 5)were classified according to findings at catheterization in the 13 patients with asymmetric septal hypertrophy. Index
terms:
Myocardium, cardium, MR. Radiology
Heart, MR. abnormalities, 51.1214
1992;
Jin Wook
Chung,
#{149}
MD
51.1214, 52.1214 511.1732 #{149} Myo-
185:441-446
I From the Departments of Diagnostic Radiology Q.H.P., Y.M.K., J.W.C., J.K.H., M.C.H.) and Internal Medicine (Y.B.P.), Seoul National University Hospital, 28, Yongon-Dong, ChongnoGu, Seoul 110-744, Korea. Received March 13, 1992; revision requested April 27; revision received May 28; accepted June 22. Supported by grant 02-92-163 from the Seoul National University Hospital Research Fund. Address reprint requests to J.H.P. C) RSNA, 1992
Young
#{149}
Bae Park,
MD
Cardiomyopathy’ cardiomyopathy
YPERTROPHIC
nondibated
the
presence, distribution, and severity of the hypertrophic process, MR imaging was performed with hypertrophic
MD MD
ofHypertrophic of magnetic
imaging
Kim, Han,
is a
hypertrophy
of the
patients thy and
with hypertrophic in five healthy
left ventricle in the absence of cardiac or systemic disease that could produce left ventricular hypertrophy (1). In asymmetric septab hypertrophy, the most frequently occurring subtype of hypertrophic cardiomyopathy, the basal septum of the left yentricle is disproportionately thickened (2-4). In apical hypertrophy, however, another subtype of hypertrophic cardiomyopathy, the apical portion is
20 patients,
markedly
based on clinical trocardiography,
thickened,
shape at left characteristic electrocardiography
subtype athy,
ventricubography giant inverted (5,6).
plan
treatment
showing
extent
accurate
and
and a T wave at Since the
is different
of hypertrophic the
a spade
for each
cardiomyop-
diagnosis
severity
for
of disease
the
phy phy five
(mean, 51/4 toms included
depth. The hypertrophy
was available volunteers [mean,
excellent
characterization
diac
sue,
depiction
between
of natural
the blood
and
contrast
cardiovascular
structure, good capability of creating images with direct multiple planes, and noninvasiveness (7-9). MR imaging is especially useful for defining the extent of diverse myocardial abnormalities (10,1 1). We performed MR imaging in patients with the diagnosis of hypertrophic cardiomyopathy to assess the capability of MR imaging to enable
evaluation
of the
presence,
tion, and severity of the process and to compare sults tion
with the findings and cine cardiac
MATERIALS From cardiac
January MR
imaging
hypertrophic the MR re-
at catheterizaangiography.
AND 1989
distribu-
to December was
performed
1991, in 20
palpitation with apical
sympin 12,
in five. hypertro-
In
revealed an inthan 10 mm in
more
septal were
findings, including echocardiography,
eleccar-
and cardiac angiograSurgical confirmation
321/2 years]),
there
was
no
history
disease.
MR imaging and
0.5-T
systems
used
were
superconductive
systems
(Gold Star, Seoul, Korea). Repetition time was based on the subject’s heart rate and was equal to the R-R interval found at electrocardiography. msec. The first section aging corresponded
Echo time was 30 obtained at MR imto the end-diastolic
phase of the cardiac cycle. To obtain an adequate image chambers,
tamed
various
sequentially.
transverse ing from The
third
or fourth
to the
biventricular
level,
we
images
left atrium four-chamber tion imaged
base
was
and
and
apex
bers in the end-diastolic obtained short-axis phase the
was
obtained along After
256
1.5 x 1.5 mm.
the
views
x 360,
next
the long those longa second set of across
the
to depict
(Fig 1). The the center
of the
a
first secof the car-
four
cham-
phase. We also of the end-dias-
at the base of the axis perpendicular
axis. Section thickness a 2-mm intersection trix
and of the miimaging at the
obtained
was
corre-
at the level
left ventricle
view through
startlevel.
usually
phase
outflow transverse
left ventricle to the bong
was 8-10 mm gap. The imaging and
car-
ob-
multisection
section
systolic
series of oblique images axis of the left ventricle. axis images were obtained,
diac
were
Initially,
ofleft ventricular trab valves. After
oblique
of the
views
imaging was performed, the supradiaphragmatic
sponded
tolic along
METHODS
clinical exertion
for one patient. In the five men, aged 30-35 years
(all
of cardiac
The
hypertro-
diagnoses of asymmetric and apical hypertrophy
catheterization, in all patients.
2.0-T
clear
in 16, and patients
phy, electrocardiography verted giant T wave
is im-
tis-
septab
13 and apical hypertropatients (15 men and aged 33-68 years
years). Common dyspnea on
chest pain six of seven
portant. The diagnosis of hypertrophic cardiomyopathy can be made with echocardiography, cardiac catheterization, and cardiac angiography. Compared with other modalities, cardiac magnetic resonance (MR) imaging has many inherent advantages, such as
of soft
asymmetric
was found in in seven. The women) were
diac phy
cardiomyopavolunteers. In the
the
pixel
size
with mawas
a.
b.
Figure 1. Routine views obtained at MR imaging verse view of normal heart reveals wide outflow (b) The section along the first oblique line on the (c) Septal and posterolateral walls of left ventricle dial thickness was measured at the basal segment
The picting
mubtisection transverse the end-diastolic phase
images in the
for evaluation of the myocardium and of the four chambers of the normal and normal position of mitral valve. Along the oblique line, long-axis views long-axis view produces four-chamber view. 3 = third oblique line, 5 = fifth were divided into basal, middle, and apical segments in the four-chamber of the septum (1), the basal segment of the postero!ateral wall (2), and the
heart. (a) Transare obtained. oblique line. view. The myocarapical segment (3).
defour-
chamber view and in the short-axis view were evaluated by two cardiac radiologists (Y.M.K., J.W.C.) for the presence, distribution, and other cardiomyopathy. distribution
the
findings For of the
hypertrophic
four-chamber
posterolatera! middle, and
view, wall apical
thicknesses
of hypertrophic evaluation of the process
each
in
and
was divided into basal, segments (Fig 1). The
of the
septum
and
era! free wall were measured segments. The myocardia! apical segment, excluding muscle, The
septa!
posterolat-
at the basal thickness of the the papillary
was measured. ratio of the myocardial
thickness
of
the basal segment of the septum to that of the posterolateral free wall was calculated, as was the ratio of the thickness of the apical segment to that of the posterolaterab free wall. On the the four-chamber each patient into
basis of MR findings in view, we categorized one of the two subtypes
of hypertrophic classification pertrophy end-diastolic mm with
cardiomyopathy.
involvement. hypertrophy diastolic with or of the
The when phase without
also eter
middle
portion
the aortic anteroposterior was
scanning, of the left atrium
root
defined
atrium
as the
than 15 mm involvement
the
ratio
the
length
of the
ascending
diamof The atrium
left
Left ventricular
outflow
were
evaluated.
cardial view
measurement were compared
LI
Mann-Whitney
The
and
the
logic findings were correlated findings at catheterization
and
n1nv
mitral of myo-
on the four-chamber statistically with and
#{149} Rail
the
results
test,
morphowith the ventricu-
the
side
of the
heart
Among the 20 patients, the basal septum was thickened more than 15 mm in the 13 patients classified with asymmetric septab hypertrophy. In those patients, only the septum was
in
In all volunteers and patients, the left ventricular wall was well demon-
involved
strated at MR imaging. Myocardial thickness could be measured with ease on the four-chamber view in the
Seven patients were classified as haying apical hypertrophy because the apical myocardium was more than 15 mm thick. Four of these patients also
end-diastolic ing
depicts
phase sharp
because
MR imag-
delineation
and
of the
epicardial
interfaces
myocardium
phase
showed
in
even
deviation)
in the
five healthy
hearts were 10.4 mm ± 2.7 in the septurn, 9.6 mm ± 1.5 in the apex, and 10.2 mm ± 1.3 in the posterobateral
wall. The ratio of the thickness of the septum to that of the posterolateral wall was 1.01 ± 0.19, and the ratio of the
thickness
posterobaterab
of the
wall
apex
was
to that of the ± 0.17.
0.95
in 10 patients. the
apex
had
involvement
tion
of the
The
myocardium. left ventricular
end-diastolic
tients,
thickness in the septal, apical, and posterobaterab walls in all five volunteers (Fig ic) (Table 1). The average myocardiab thicknesses (mean ± stan-
dard de-
left
RESULTS
the
was
and
of the
patients.
of the The
septum.
enlargement
anteroposterior to the diameter
those
endocardial
aorta.
valve
4h17
apical end-
in the systolic phase. diameter of the left
between
scending
was in the
of the
the left atrial
transverse obtained of the
classification the apex
was thicker concomitant
To quantify with
The
was asymmetric septa! hywhen the basal septum in the phase was thicker than 15 or without concomitant apical
lography
pa-
involved.
of the
with
hypertrophy
three
In three also
middle
por-
septum.
13 patients
septab sure
was
groups
asymmetric
were
according
gradient
in left
divided
to the
into
pres-
ventricular
out-
flow demonstrated at catheterization. The pressure gradient was higher than 30 mm Hg in the resting state (resting obstructive hypertrophy) in five cases. The pressure gradient was obvious only during the provocation test (latent obstructive hypertrophy)
in three
cases.
There
was
no pressure
gradient
(nonobstructive phy) in five cases. The septab myocardium metrically
thickened
hypertrowas in the
asym-
patients
November
1992
b.
a. Figure
2.
end
(a) MR
diastole
ment motion
images
reveals
of asymmetric
asymmetric
septal
thickening
of mitral valve (arrow), which of mitral valve is demonstrated
Moderate
mitral
Table
regurgitant
of interventricular
obstructs in the
flow opacifies
at MR
Ima ging,
Car diac
(b) Systolic
in 44-year-old
phase
woman
(case
of the four-chamber
4). Four-chamber
view
ventricle. (c) Linear area of decreased in left anterior oblique view obtained
Sex/age (y) Distribution
and
Left Ven triculography
(n
5)
=
in 13 Pati eMs
shows
opacity at cine
view
anterior
in
displace-
due to systolic anterior left ventriculography.
wi th Asymmetric
Latent Obstructive Hypertrophy (n = 3)
Obstructive
Hypertrophy
CaseNo.
Septal
Nonobstructive
(n
=
Hypertrophy
Hypertrophy 5)
1
2
3
4
5
6
7
8
9
10
11
12
13
M/47
F/48
M/58
F/44
M/62
M/49
Ff61
Ff68
Mf36
M/33
Mf36
Mf65
Mf64
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-SfA
B, M-S/A
B, M-S/A
of myo-
cardial hypertrophy Wall thickness
B, M-S
B, M-S
(mm) Septal
20
28
22
35
28
21
25
34
18
28
15
15
16
Apical
10
14
12
17
14
10
11
14
11
10
21
23
20
10
13
11
16
14
10
11
14
9
9
11
10
10
Posterolaterab Ratio Septa!/postero!atera! Apical/posterolat-
era! Left atrium/aorta Left ventricular
valve
Note-B, M-S(A) * Associated mitral
with
asymmetric in those
latent
2.0
2.2
2.0
2.1
2.3
2.4
2.0
3.1
1.4
1.5
1.6
1.0 1.6
1.1 1.7
1.1 1.4
1.1 1.9
1.0 1.9
1.0 1.4
1.0 1.4
1.0 1.2
1.2 1.9*
1.1 1.0
1.9 1.4
2.3 1.3
2.0 1.4
Yes
No
Yes
No
No
No
No
No
No
No
No
No
120
42(88)
30(140)
125
100
0(120)
5(80)
22(80)
5
0
0
0
0
Yes Moderate
Yes Moderate
Some
No
No
No
No
No
No
Minima!
. . .
. . .
. . .
. . .
. . .
Yes Moderate
regurgitation
cialby
2.2
Yes
(mmHg) Systolic anterior motion of mitral Mitral
2.0
out-
flow tract obstruction Resting (provoked)
=
Yes
Yes Minima!
Mild
basal and middle stenosis.
portion
hypertrophy,
espe-
with
resting
obstructive
obstructive
hypertrophy.
The
mean septal thickness was 23.5 mm ± 6.8, while the mean thickness of the apex was 14.3 mm ± 1.7 in the 13 patients with asymmetric septal hypertrophy. In apical hypertrophy,
mean
apical
± 4.1,
thickness
while
the
was
mean
of the septum ratio of septab
was 14.3 mm to posterobaterab
thickness
2.05
was
± 0.44
25.3
oe
W.T..1.......
‘I
The
wall
in the
group with
No Minimal
...
of septum/(apex).
apical hypertrophy. The ratios of apicab to posterolaterab wall thickness were 1.29 ± 0.45 and 2.21 ± 0.51 in the two groups, respectively. The septab and apical myocardiab thicknesses in patients with hypertrophic cardiomyopathy were significantly higher
1). The cubated x 1.96.
than
obatera! wall thickness was higher than 2.0 in all cases. Findings in four cases were of left atrial enlargement,
in those
(P < .05). terolateral
thickness ± 1.7.
with asymmetric septab hypertrophy and was 1.26 ± 0.29 in the group -7_.1_____.
septum.
type,
left atrium.
Resting
mm
obstructive
the outflow tract of the left outflow of the left ventricle
Catheterization,
Finding
the
resting
2
Findings
and
c.
hypertrophy,
group trophy)
with and
wall
thickness
also
significantly
with
with
normal
hearts
The ratios of septal to poswall thickness (in the
normal
asymmetric of apical
septab
hyper-
to posterolaterab
(in both
groups)
higher hearts (P
than < .05)
were in those (Table
95% confidence bevel as mean ± standard
was caldeviation
The septum alone was involved all five cases of resting obstructive asymmetric septab hypertrophy
(Table
2). The
ratio
of septab
in (Fig
to poster-
with the ratio of the diameter left atrium to that of the aorta
of the being
higher
the
ventricular chamber
than
1.5.
In four
outflow view
in the
tract
cases,
on the
left
four-
end-diastolic rI__3!___1_____.
.-.
2)
3. Figures
4.
3, 4.
systolic anterior hypertrophy, left ventricle.
(3) Transverse motion nonobstructive
MR image of asymmetric of mitral valve (arrow), which type, in 33-year-old man
phase showed narrowing due to basal septab thickening and a displaced mitrab valve (Figs 2, 3). In four cases anterior displacement of the mitral valve toward the septum that induced obstruction at the outflow of the left ventricle was demonstrated on the transverse image obtained in the systolic phase (Fig 4). The resting pressure gradient across the outflow tract ranged from 30 to 125 mm Hg. The left anterior oblique view at cine cardiac angiography revealed variable degrees of systolic anterior motion of the mitral valve, with a transverse, bandlike, or wedge-shaped filling de-
fect at outflow regurgitation ventricubography
in all five cases. was
also noted in all cases.
444
#{149} Radiology
Table
resting narrowing asymmetric
obstructive type, of left ventricular septal thickening
in 47-year-old man (case 1) shows marked outflow. (4) MR image of asymmetric septal without obstructive lesion at outflow of
3
at MR Imagin Cardiac Catheterization, Left Ventricubography, Electrocardiography in Seven Patients with Apical Hypertrophy
Findings
Case
3
4
Sex/age (y) Distribution of myocardia! hypertro-
M/45
M/57
M/41
M/57
F/52
phy Wall thickness
M-SfA
M-S/A
M-S/A
M-S/A
Septal
15 19 11
16 29 9
15 28 12
16
14
12
25
25
21
11
13
12
Ratio Septab/posterolaterab Apicab/posterolateral Left atrium/aorta
Gradient
(mm Hg)
Spade-shaped deformity ofleft yenhide
Giant
1-wave
Note.-M-S/A
A 12 30 13
=
also
6
7
M/56
M/47
A
A
1.4
0.9
1.8
1.3
1.5
1.1
1.0
1.7 1.3 0
2.3 1.0 0
3.2
2.3
2.3
1.9
1.8
1.4 0
1.1 0
0.8
1.3
1.0
0
0
0
Yes
No
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
middle
portion
of septum/apex,
structive asymmetric septal hypertrophy (Table 2). Only the septum was involved in two cases (Fig 4), and the
was
5
inver-
sion at electrocardiography
apex
No.
2
Apical Posterolateral
at left
and
1
Finding
Mitral
Only the septum was thickened in all three cases of latent obstructive asymmetric septal hypertrophy (Table 2), with the ratio of septal to posterolateral wall thickness higher than 2.0. However, left atriab enlargement was not evident. There was no demonstrable narrowing of outflow of the left ventricle and no abnormality of the mitral valve. During catheterization, however, a pressure gradient of 80120 mm Hg was induced by means of a provocation test such as initiation of a ventricular premature beat or injection of isoproterenob hydrochloride. Systolic anterior motion of the mitral valve was not evident, and only mild mitral regurgitation was noted at left ventricubography. There were two subtypes of nonob-
septal hypertrophy, induces severe (case 10) shows
involved
in three
cases.
The wall
ratio of septal to posterobaterab thickness ranged from 1.4 to 3.1.
The
left atrium
was
not
During catheterization, gradient was demonstrated outflow. Neither systolic tion of the mitral valve
enlarged. pressure across anterior nor mitral
A
=
apex.
gurgitation shaped at left patients
the more-
demonstrated
at left
However,
a spade-
deformity was demonstrated ventricubography in the three with apical thickening.
In patients (Table
no
was
ventricubography.
with
3), myocardial
apical
hypertrophy
involvement
that was seen on the four-chamber view in the end-diastolic phase was limited to only the apical segment in three
cases
(Fig
5). Concomitant November
in1992
healthy and 10.8 whereas trophic surements
cm
subjects was 10.2 mm ± 0.4 mm ± 0.5, respectively, in patients with hypercardiomyopathy, these meawere 2.2 cm ± 0.8 and 1.3
± 0.17,
respectively.
These
results
similar to ours in healthy vobunteers and in patients with asymmetric septab hypertrophy. We set the criteria of myocardiab thickening to be at least 15 mm. The ratios of wall thickwere
ness-septab
a.
b.
Figure 5. (a) MR image of apical hypertrophy in 41-year-old view of heart in end diastole demonstrates disproportionate ventriculogram reveals spade-shaped deformity in diastole.
man apical
volvement the septum
at left ventricubography
these
of the apical segment of was seen in four cases. In
patients,
the
basal
septum
was
not involved, and the ratio of septal to posterobateral wall thickness ranged from 0.9 to 1.8. The ratio of apical to posterolaterab wall thickness ranged from 1.8 to 3.2. There was no evidence of left atriab enlargement. Findings at catheterization showed no pressure gradient across the outflow tract of the left ventricle. A spade-shaped deformity was demonstrated at left ventricubography in five cases
(Fig
5).
DISCUSSION Hypertrophic characterized hypertrophied ventricle
cardiomyopathy by the presence and nondilated
in a patient
is of a left
without
a his-
tory of cardiac and/or systemic disease that would cause left ventricular hypertrophy. The distribution of the hypertrophic process is usually asyrnmetric; however, 2%-20% of symrnetric involvement is also (4,12,13). Histologically,
reported muscle
cell
disorganization is observed, especially in the ventricular septum (13). There are many synonyms for asymmetric septal hypertrophy, including idiopathic hypertrophic subaortic stenosis,
subaortic
stenosis,
and
hyper-
trophic obstructive cardiomyopathy (2-4). Apical hypertrophy, first described by Sakamoto et a! (5) in Japanese patients, is also a distinct subtype of hypertrophic cardiomyopathy (6). Myocardiab wall thickening, which is confined to the most apical portion of the left ventricle, is associated with the presence of a characteristic electrocardiographic pattern of a giant inverted T wave and of a spadeshaped deformity of the left ventricu1_1_.__
1o
*
T.....L.....
bar cavity
(case 3). Four-chamber thickening. (b) Cine
left
(5,6). Apical hypertrophy occurs in 25%-33% of cases of hypertrophic cardiomyopathy in Japan and Korea
trophy.
but in only
2%-3% of such cases in western countries, a finding that is suggestive of racial differences (4,12, 14). Apical hypertrophy, which is usuably clinically benign, is frequently associated with systemic hypertension in older men (14). The pathophysiobogic findings of hypertrophic cardiomyopathy indude left ventricular hypertrophy that beads to subaortic stenosis, abnorma! diastolic function, and myocardial ischemia. Symptoms include exertional angina and dyspnea, fatigue, syncope, arrhythmia, and sudden death (13,14). Another important pathophysiologic mechanism is systolic anterior motion of the mitral valve. It is suggested that the Venturi effect of rapid flow through the narrow outflow tract causes the anterior leaflet of the mitral
valve
to displace
anteriorly
to-
ward the septum. Again, mitral regurgitation is explained by the presence of the displaced mitral leaflet (13). Cardiac MR imaging with electrocardiographic gating sharply de!ineates the myocardium between the high-signal-intensity area of epicardial fat and the signal void of the cayity. Thus, MR imaging in patients with hypertrophic cardiomyopathy provides useful information about the myocardial hypertrophic process and enables measurement of the wall thickness and of the myocardial mass (7-11).
We
cardial
mass
by Higgins
onstrated
did
not
measure
in our
series.
et a! (15),
varying
MR
the
myo-
ing
and
api-
was
gross
correlation
pressure gradient across tract of the left ventricle at catheterization and of asymmetric thickening septum demonstrated at especially in association valve displacement dur-
systobe.
Echocardiography accepted
diagnosis
as a screening
of hypertrophic
has been study
widely for the
cardiomy-
opathy and as a definitive diagnostic modality at the same time (13,16,17). However, the advantages of MR imaging over two-dimensional echocardiography include a large field of view and sharp interfaces that enable accurate myocardial evaluation for the location, severity, and extent of the abnormality. On the basis of our experience, MR imaging can provide objective information for the appropriate treatment of hypertrophic cardiomyopathy. More detailed analysis of myocardia! abnormality for the evaluation of mitrab valve abnormality can be anticipated with cine and contrast material-enhanced MR imaging.
#{149}
References 1. Goodwin 2. 3.
JF. The frontiers of cardiomyopathy. Br Heart J 1982; 48:1-18. Shah PM. IHSS-HOCM-MSS-ASH? Circulation 1975; 51:577-580. Brunwald E, Morrow AG, Cornell WP, Aygen MM. Hillbish TF. Idiopathic hypertrophic subaortic stenosis. Am J Med 1960;
29:924-925. 4.
dem-
wall thicknesses through the left ventricubar myocardium. The thickness of the septab and posterolaterab wall in
There
between the the outflow demonstrated the severity of the basal MR imaging, with mitral
In a study images
to posterolateral
cab to posterolaterab-indicate the severity of asymmetric thickening in patients with hypertrophic cardiomyopathy (16). In our series, transverse MR imaging demonstrated anterior displacement of the mitral valve during systobe. Also, narrowing of left ventricular outflow and an enlarged left atrium were revealed in patients with resting obstructive asymmetric septal hyper-
abnormal
5.
Wigle ED, Heimbecker RO, Gunton RW. Idiopathic ventricular septal hypertrophy causing muscular subaortic stenosis. Circulation 1962; 26:325-340. Sakamoto T, Tei C, Murayama M, et a!. Giant T wave inversion as a manifestation of asymmetrical apical hypertrophy (AAH) of the left ventricle: echocardiographic and
6.
7.
8.
9.
, . - Jpn HeartJ 1976; 17:611-629. Yamaguchi H, Ishimura 1, Nishiyama 5, et a!. Hypertrophic nonobstructive cardiomyopathy with giant negative T waves (apical hypertrophy): ventriculographic and echocardiographic features in 30 patients. Am J Cardiol 1979; 44:401-412. Kaufman L, Crooks LE, Sheldon PE. The potential impact of nuclear magnetic resonance imaging on cardiovascular diagnosis. Circulation 1983; 67:251-259. Lanzer P, Botvinick E, Kaufman L, David P, Lipton MJ, Higgins CB. Cardiac imaging using gated nuclear magnetic resonance. Radiology 1984; 150:121-127. Higgins CB, Stark D, McNamara M, Lanzer P, Crooks LE, Kaufman L. Multiple magnetic resonance imaging of the heart and
10.
11.
12.
13.
14.
446
Radiolov
#{149}
major vessels: studies in normal volunteers. AJR 1984; 142:661-667. Wesbey G, Lanzer P, Botvinick E, Lipton MJ, Higgins CB. Imaging and characterization of acute myocardial infarction in vivo by gated nuclear magnetic resonance. Circulation 1984; 69:125-130. Higgins CB, Lanzer P, Stark D, et a!. Imaging by nuclear magnetic resonance in patients with chronic ischemic heart disease. Circulation 1984; 69:523-531. Louie EK, Maron BJ. Apical hypertrophic cardiomyopathy: clinical and two-dimensional echocardiographic assessment. Ann Intern Med 1987; 106:663-670. Maron BJ, Bonow RO, Cannon RO III, Leon MB, Epstein SE. Hypertrophic cardiomyopathy: interrelations of clinical manifestations, pathophysiology, and therapy. N EnglJ Med 1987; 316:780-789. Park YB, Lee WS, Kim DK, Choi YS, Seo JD, Lee YW. Clinical and morphological features of hypertrophic cardiomyopathy in
15.
16.
17.
Korean patients. J Korean Med Sci 1989; 4:163-169. Higgins CB, Byrd BF, Stark D, et a!. Magnetic resonance imaging in hypertrophic cardiomyopathy. Am J Cardiol 1985; 55: 1121-1 126. Maron BJ, Epstein SE. Hypertrophic cardiomyopathy: recent observations regarding the specificity of three hallmarks of the disease: asymmetric septal hypertrophy, septal disorganization and systolic anterior motion of the anterior mitral leaflet. Am Cardiol 1980; 45:141-154. Henry WL, Clark CE, Epstein SE. Asymmetric septal hypertrophy (ASH): echocardiographic identification of the pathognomonic anatomic abnormality of IHSS. Circulation 1973; 47:225-233.
November
1992
Yang Mm Man Chung
#{149} #{149}
Imaging
MR To assess
the capability
resonance
(MR)
H
to define
in 20 patients cardiomyopathy
and in five healthy volunteers. Among the 20 patients, 13 were sified
as having
asymmetric
clas-
septal
hypertrophy and seven as having apical hypertrophy. The mean myocardial thickness in the four-chamber view obtained in end diastole in asymmetric septal hypertrophy was 23.5 mm ± 6.8 (mean ± standard deviation) in the basal septum; the ratio of septal to posterolateral wall thickness was 2.05 ± 0.44 (P < 05); those values were 10.4 mm ± 2.7 and 1.01 ± 0.19,
respectively,
unteers.
The
in five
mean
healthy
myocardial
vol-
thick-
ness
in apical hypertrophy was 25.3 mm ± 4.1 in the apex, and the ratio was 2.21 ± 0.51 (P < .05); these values were 9.6 mm ± 1.5 and 0.95 ± 0.17,
respectively, in five healthy volunteers. Three different subtypes of hypertrophic cardiomyopathy-resting obstructive (n = 5), latent obstructive (n = 3), and nonobstructive (n = 5)were classified according to findings at catheterization in the 13 patients with asymmetric septal hypertrophy. Index
terms:
Myocardium, cardium, MR. Radiology
Heart, MR. abnormalities, 51.1214
1992;
Jin Wook
Chung,
#{149}
MD
51.1214, 52.1214 511.1732 #{149} Myo-
185:441-446
I From the Departments of Diagnostic Radiology Q.H.P., Y.M.K., J.W.C., J.K.H., M.C.H.) and Internal Medicine (Y.B.P.), Seoul National University Hospital, 28, Yongon-Dong, ChongnoGu, Seoul 110-744, Korea. Received March 13, 1992; revision requested April 27; revision received May 28; accepted June 22. Supported by grant 02-92-163 from the Seoul National University Hospital Research Fund. Address reprint requests to J.H.P. C) RSNA, 1992
Young
#{149}
Bae Park,
MD
Cardiomyopathy’ cardiomyopathy
YPERTROPHIC
nondibated
the
presence, distribution, and severity of the hypertrophic process, MR imaging was performed with hypertrophic
MD MD
ofHypertrophic of magnetic
imaging
Kim, Han,
is a
hypertrophy
of the
patients thy and
with hypertrophic in five healthy
left ventricle in the absence of cardiac or systemic disease that could produce left ventricular hypertrophy (1). In asymmetric septab hypertrophy, the most frequently occurring subtype of hypertrophic cardiomyopathy, the basal septum of the left yentricle is disproportionately thickened (2-4). In apical hypertrophy, however, another subtype of hypertrophic cardiomyopathy, the apical portion is
20 patients,
markedly
based on clinical trocardiography,
thickened,
shape at left characteristic electrocardiography
subtype athy,
ventricubography giant inverted (5,6).
plan
treatment
showing
extent
accurate
and
and a T wave at Since the
is different
of hypertrophic the
a spade
for each
cardiomyop-
diagnosis
severity
for
of disease
the
phy phy five
(mean, 51/4 toms included
depth. The hypertrophy
was available volunteers [mean,
excellent
characterization
diac
sue,
depiction
between
of natural
the blood
and
contrast
cardiovascular
structure, good capability of creating images with direct multiple planes, and noninvasiveness (7-9). MR imaging is especially useful for defining the extent of diverse myocardial abnormalities (10,1 1). We performed MR imaging in patients with the diagnosis of hypertrophic cardiomyopathy to assess the capability of MR imaging to enable
evaluation
of the
presence,
tion, and severity of the process and to compare sults tion
with the findings and cine cardiac
MATERIALS From cardiac
January MR
imaging
hypertrophic the MR re-
at catheterizaangiography.
AND 1989
distribu-
to December was
performed
1991, in 20
palpitation with apical
sympin 12,
in five. hypertro-
In
revealed an inthan 10 mm in
more
septal were
findings, including echocardiography,
eleccar-
and cardiac angiograSurgical confirmation
321/2 years]),
there
was
no
history
disease.
MR imaging and
0.5-T
systems
used
were
superconductive
systems
(Gold Star, Seoul, Korea). Repetition time was based on the subject’s heart rate and was equal to the R-R interval found at electrocardiography. msec. The first section aging corresponded
Echo time was 30 obtained at MR imto the end-diastolic
phase of the cardiac cycle. To obtain an adequate image chambers,
tamed
various
sequentially.
transverse ing from The
third
or fourth
to the
biventricular
level,
we
images
left atrium four-chamber tion imaged
base
was
and
and
apex
bers in the end-diastolic obtained short-axis phase the
was
obtained along After
256
1.5 x 1.5 mm.
the
views
x 360,
next
the long those longa second set of across
the
to depict
(Fig 1). The the center
of the
a
first secof the car-
four
cham-
phase. We also of the end-dias-
at the base of the axis perpendicular
axis. Section thickness a 2-mm intersection trix
and of the miimaging at the
obtained
was
corre-
at the level
left ventricle
view through
startlevel.
usually
phase
outflow transverse
left ventricle to the bong
was 8-10 mm gap. The imaging and
car-
ob-
multisection
section
systolic
series of oblique images axis of the left ventricle. axis images were obtained,
diac
were
Initially,
ofleft ventricular trab valves. After
oblique
of the
views
imaging was performed, the supradiaphragmatic
sponded
tolic along
METHODS
clinical exertion
for one patient. In the five men, aged 30-35 years
(all
of cardiac
The
hypertro-
diagnoses of asymmetric and apical hypertrophy
catheterization, in all patients.
2.0-T
clear
in 16, and patients
phy, electrocardiography verted giant T wave
is im-
tis-
septab
13 and apical hypertropatients (15 men and aged 33-68 years
years). Common dyspnea on
chest pain six of seven
portant. The diagnosis of hypertrophic cardiomyopathy can be made with echocardiography, cardiac catheterization, and cardiac angiography. Compared with other modalities, cardiac magnetic resonance (MR) imaging has many inherent advantages, such as
of soft
asymmetric
was found in in seven. The women) were
diac phy
cardiomyopavolunteers. In the
the
pixel
size
with mawas
a.
b.
Figure 1. Routine views obtained at MR imaging verse view of normal heart reveals wide outflow (b) The section along the first oblique line on the (c) Septal and posterolateral walls of left ventricle dial thickness was measured at the basal segment
The picting
mubtisection transverse the end-diastolic phase
images in the
for evaluation of the myocardium and of the four chambers of the normal and normal position of mitral valve. Along the oblique line, long-axis views long-axis view produces four-chamber view. 3 = third oblique line, 5 = fifth were divided into basal, middle, and apical segments in the four-chamber of the septum (1), the basal segment of the postero!ateral wall (2), and the
heart. (a) Transare obtained. oblique line. view. The myocarapical segment (3).
defour-
chamber view and in the short-axis view were evaluated by two cardiac radiologists (Y.M.K., J.W.C.) for the presence, distribution, and other cardiomyopathy. distribution
the
findings For of the
hypertrophic
four-chamber
posterolatera! middle, and
view, wall apical
thicknesses
of hypertrophic evaluation of the process
each
in
and
was divided into basal, segments (Fig 1). The
of the
septum
and
era! free wall were measured segments. The myocardia! apical segment, excluding muscle, The
septa!
posterolat-
at the basal thickness of the the papillary
was measured. ratio of the myocardial
thickness
of
the basal segment of the septum to that of the posterolateral free wall was calculated, as was the ratio of the thickness of the apical segment to that of the posterolaterab free wall. On the the four-chamber each patient into
basis of MR findings in view, we categorized one of the two subtypes
of hypertrophic classification pertrophy end-diastolic mm with
cardiomyopathy.
involvement. hypertrophy diastolic with or of the
The when phase without
also eter
middle
portion
the aortic anteroposterior was
scanning, of the left atrium
root
defined
atrium
as the
than 15 mm involvement
the
ratio
the
length
of the
ascending
diamof The atrium
left
Left ventricular
outflow
were
evaluated.
cardial view
measurement were compared
LI
Mann-Whitney
The
and
the
logic findings were correlated findings at catheterization
and
n1nv
mitral of myo-
on the four-chamber statistically with and
#{149} Rail
the
results
test,
morphowith the ventricu-
the
side
of the
heart
Among the 20 patients, the basal septum was thickened more than 15 mm in the 13 patients classified with asymmetric septab hypertrophy. In those patients, only the septum was
in
In all volunteers and patients, the left ventricular wall was well demon-
involved
strated at MR imaging. Myocardial thickness could be measured with ease on the four-chamber view in the
Seven patients were classified as haying apical hypertrophy because the apical myocardium was more than 15 mm thick. Four of these patients also
end-diastolic ing
depicts
phase sharp
because
MR imag-
delineation
and
of the
epicardial
interfaces
myocardium
phase
showed
in
even
deviation)
in the
five healthy
hearts were 10.4 mm ± 2.7 in the septurn, 9.6 mm ± 1.5 in the apex, and 10.2 mm ± 1.3 in the posterobateral
wall. The ratio of the thickness of the septum to that of the posterolateral wall was 1.01 ± 0.19, and the ratio of the
thickness
posterobaterab
of the
wall
apex
was
to that of the ± 0.17.
0.95
in 10 patients. the
apex
had
involvement
tion
of the
The
myocardium. left ventricular
end-diastolic
tients,
thickness in the septal, apical, and posterobaterab walls in all five volunteers (Fig ic) (Table 1). The average myocardiab thicknesses (mean ± stan-
dard de-
left
RESULTS
the
was
and
of the
patients.
of the The
septum.
enlargement
anteroposterior to the diameter
those
endocardial
aorta.
valve
4h17
apical end-
in the systolic phase. diameter of the left
between
scending
was in the
of the
the left atrial
transverse obtained of the
classification the apex
was thicker concomitant
To quantify with
The
was asymmetric septa! hywhen the basal septum in the phase was thicker than 15 or without concomitant apical
lography
pa-
involved.
of the
with
hypertrophy
three
In three also
middle
por-
septum.
13 patients
septab sure
was
groups
asymmetric
were
according
gradient
in left
divided
to the
into
pres-
ventricular
out-
flow demonstrated at catheterization. The pressure gradient was higher than 30 mm Hg in the resting state (resting obstructive hypertrophy) in five cases. The pressure gradient was obvious only during the provocation test (latent obstructive hypertrophy)
in three
cases.
There
was
no pressure
gradient
(nonobstructive phy) in five cases. The septab myocardium metrically
thickened
hypertrowas in the
asym-
patients
November
1992
b.
a. Figure
2.
end
(a) MR
diastole
ment motion
images
reveals
of asymmetric
asymmetric
septal
thickening
of mitral valve (arrow), which of mitral valve is demonstrated
Moderate
mitral
Table
regurgitant
of interventricular
obstructs in the
flow opacifies
at MR
Ima ging,
Car diac
(b) Systolic
in 44-year-old
phase
woman
(case
of the four-chamber
4). Four-chamber
view
ventricle. (c) Linear area of decreased in left anterior oblique view obtained
Sex/age (y) Distribution
and
Left Ven triculography
(n
5)
=
in 13 Pati eMs
shows
opacity at cine
view
anterior
in
displace-
due to systolic anterior left ventriculography.
wi th Asymmetric
Latent Obstructive Hypertrophy (n = 3)
Obstructive
Hypertrophy
CaseNo.
Septal
Nonobstructive
(n
=
Hypertrophy
Hypertrophy 5)
1
2
3
4
5
6
7
8
9
10
11
12
13
M/47
F/48
M/58
F/44
M/62
M/49
Ff61
Ff68
Mf36
M/33
Mf36
Mf65
Mf64
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-S
B, M-SfA
B, M-S/A
B, M-S/A
of myo-
cardial hypertrophy Wall thickness
B, M-S
B, M-S
(mm) Septal
20
28
22
35
28
21
25
34
18
28
15
15
16
Apical
10
14
12
17
14
10
11
14
11
10
21
23
20
10
13
11
16
14
10
11
14
9
9
11
10
10
Posterolaterab Ratio Septa!/postero!atera! Apical/posterolat-
era! Left atrium/aorta Left ventricular
valve
Note-B, M-S(A) * Associated mitral
with
asymmetric in those
latent
2.0
2.2
2.0
2.1
2.3
2.4
2.0
3.1
1.4
1.5
1.6
1.0 1.6
1.1 1.7
1.1 1.4
1.1 1.9
1.0 1.9
1.0 1.4
1.0 1.4
1.0 1.2
1.2 1.9*
1.1 1.0
1.9 1.4
2.3 1.3
2.0 1.4
Yes
No
Yes
No
No
No
No
No
No
No
No
No
120
42(88)
30(140)
125
100
0(120)
5(80)
22(80)
5
0
0
0
0
Yes Moderate
Yes Moderate
Some
No
No
No
No
No
No
Minima!
. . .
. . .
. . .
. . .
. . .
Yes Moderate
regurgitation
cialby
2.2
Yes
(mmHg) Systolic anterior motion of mitral Mitral
2.0
out-
flow tract obstruction Resting (provoked)
=
Yes
Yes Minima!
Mild
basal and middle stenosis.
portion
hypertrophy,
espe-
with
resting
obstructive
obstructive
hypertrophy.
The
mean septal thickness was 23.5 mm ± 6.8, while the mean thickness of the apex was 14.3 mm ± 1.7 in the 13 patients with asymmetric septal hypertrophy. In apical hypertrophy,
mean
apical
± 4.1,
thickness
while
the
was
mean
of the septum ratio of septab
was 14.3 mm to posterobaterab
thickness
2.05
was
± 0.44
25.3
oe
W.T..1.......
‘I
The
wall
in the
group with
No Minimal
...
of septum/(apex).
apical hypertrophy. The ratios of apicab to posterolaterab wall thickness were 1.29 ± 0.45 and 2.21 ± 0.51 in the two groups, respectively. The septab and apical myocardiab thicknesses in patients with hypertrophic cardiomyopathy were significantly higher
1). The cubated x 1.96.
than
obatera! wall thickness was higher than 2.0 in all cases. Findings in four cases were of left atrial enlargement,
in those
(P < .05). terolateral
thickness ± 1.7.
with asymmetric septab hypertrophy and was 1.26 ± 0.29 in the group -7_.1_____.
septum.
type,
left atrium.
Resting
mm
obstructive
the outflow tract of the left outflow of the left ventricle
Catheterization,
Finding
the
resting
2
Findings
and
c.
hypertrophy,
group trophy)
with and
wall
thickness
also
significantly
with
with
normal
hearts
The ratios of septal to poswall thickness (in the
normal
asymmetric of apical
septab
hyper-
to posterolaterab
(in both
groups)
higher hearts (P
than < .05)
were in those (Table
95% confidence bevel as mean ± standard
was caldeviation
The septum alone was involved all five cases of resting obstructive asymmetric septab hypertrophy
(Table
2). The
ratio
of septab
in (Fig
to poster-
with the ratio of the diameter left atrium to that of the aorta
of the being
higher
the
ventricular chamber
than
1.5.
In four
outflow view
in the
tract
cases,
on the
left
four-
end-diastolic rI__3!___1_____.
.-.
2)
3. Figures
4.
3, 4.
systolic anterior hypertrophy, left ventricle.
(3) Transverse motion nonobstructive
MR image of asymmetric of mitral valve (arrow), which type, in 33-year-old man
phase showed narrowing due to basal septab thickening and a displaced mitrab valve (Figs 2, 3). In four cases anterior displacement of the mitral valve toward the septum that induced obstruction at the outflow of the left ventricle was demonstrated on the transverse image obtained in the systolic phase (Fig 4). The resting pressure gradient across the outflow tract ranged from 30 to 125 mm Hg. The left anterior oblique view at cine cardiac angiography revealed variable degrees of systolic anterior motion of the mitral valve, with a transverse, bandlike, or wedge-shaped filling de-
fect at outflow regurgitation ventricubography
in all five cases. was
also noted in all cases.
444
#{149} Radiology
Table
resting narrowing asymmetric
obstructive type, of left ventricular septal thickening
in 47-year-old man (case 1) shows marked outflow. (4) MR image of asymmetric septal without obstructive lesion at outflow of
3
at MR Imagin Cardiac Catheterization, Left Ventricubography, Electrocardiography in Seven Patients with Apical Hypertrophy
Findings
Case
3
4
Sex/age (y) Distribution of myocardia! hypertro-
M/45
M/57
M/41
M/57
F/52
phy Wall thickness
M-SfA
M-S/A
M-S/A
M-S/A
Septal
15 19 11
16 29 9
15 28 12
16
14
12
25
25
21
11
13
12
Ratio Septab/posterolaterab Apicab/posterolateral Left atrium/aorta
Gradient
(mm Hg)
Spade-shaped deformity ofleft yenhide
Giant
1-wave
Note.-M-S/A
A 12 30 13
=
also
6
7
M/56
M/47
A
A
1.4
0.9
1.8
1.3
1.5
1.1
1.0
1.7 1.3 0
2.3 1.0 0
3.2
2.3
2.3
1.9
1.8
1.4 0
1.1 0
0.8
1.3
1.0
0
0
0
Yes
No
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
middle
portion
of septum/apex,
structive asymmetric septal hypertrophy (Table 2). Only the septum was involved in two cases (Fig 4), and the
was
5
inver-
sion at electrocardiography
apex
No.
2
Apical Posterolateral
at left
and
1
Finding
Mitral
Only the septum was thickened in all three cases of latent obstructive asymmetric septal hypertrophy (Table 2), with the ratio of septal to posterolateral wall thickness higher than 2.0. However, left atriab enlargement was not evident. There was no demonstrable narrowing of outflow of the left ventricle and no abnormality of the mitral valve. During catheterization, however, a pressure gradient of 80120 mm Hg was induced by means of a provocation test such as initiation of a ventricular premature beat or injection of isoproterenob hydrochloride. Systolic anterior motion of the mitral valve was not evident, and only mild mitral regurgitation was noted at left ventricubography. There were two subtypes of nonob-
septal hypertrophy, induces severe (case 10) shows
involved
in three
cases.
The wall
ratio of septal to posterobaterab thickness ranged from 1.4 to 3.1.
The
left atrium
was
not
During catheterization, gradient was demonstrated outflow. Neither systolic tion of the mitral valve
enlarged. pressure across anterior nor mitral
A
=
apex.
gurgitation shaped at left patients
the more-
demonstrated
at left
However,
a spade-
deformity was demonstrated ventricubography in the three with apical thickening.
In patients (Table
no
was
ventricubography.
with
3), myocardial
apical
hypertrophy
involvement
that was seen on the four-chamber view in the end-diastolic phase was limited to only the apical segment in three
cases
(Fig
5). Concomitant November
in1992
healthy and 10.8 whereas trophic surements
cm
subjects was 10.2 mm ± 0.4 mm ± 0.5, respectively, in patients with hypercardiomyopathy, these meawere 2.2 cm ± 0.8 and 1.3
± 0.17,
respectively.
These
results
similar to ours in healthy vobunteers and in patients with asymmetric septab hypertrophy. We set the criteria of myocardiab thickening to be at least 15 mm. The ratios of wall thickwere
ness-septab
a.
b.
Figure 5. (a) MR image of apical hypertrophy in 41-year-old view of heart in end diastole demonstrates disproportionate ventriculogram reveals spade-shaped deformity in diastole.
man apical
volvement the septum
at left ventricubography
these
of the apical segment of was seen in four cases. In
patients,
the
basal
septum
was
not involved, and the ratio of septal to posterobateral wall thickness ranged from 0.9 to 1.8. The ratio of apical to posterolaterab wall thickness ranged from 1.8 to 3.2. There was no evidence of left atriab enlargement. Findings at catheterization showed no pressure gradient across the outflow tract of the left ventricle. A spade-shaped deformity was demonstrated at left ventricubography in five cases
(Fig
5).
DISCUSSION Hypertrophic characterized hypertrophied ventricle
cardiomyopathy by the presence and nondilated
in a patient
is of a left
without
a his-
tory of cardiac and/or systemic disease that would cause left ventricular hypertrophy. The distribution of the hypertrophic process is usually asyrnmetric; however, 2%-20% of symrnetric involvement is also (4,12,13). Histologically,
reported muscle
cell
disorganization is observed, especially in the ventricular septum (13). There are many synonyms for asymmetric septal hypertrophy, including idiopathic hypertrophic subaortic stenosis,
subaortic
stenosis,
and
hyper-
trophic obstructive cardiomyopathy (2-4). Apical hypertrophy, first described by Sakamoto et a! (5) in Japanese patients, is also a distinct subtype of hypertrophic cardiomyopathy (6). Myocardiab wall thickening, which is confined to the most apical portion of the left ventricle, is associated with the presence of a characteristic electrocardiographic pattern of a giant inverted T wave and of a spadeshaped deformity of the left ventricu1_1_.__
1o
*
T.....L.....
bar cavity
(case 3). Four-chamber thickening. (b) Cine
left
(5,6). Apical hypertrophy occurs in 25%-33% of cases of hypertrophic cardiomyopathy in Japan and Korea
trophy.
but in only
2%-3% of such cases in western countries, a finding that is suggestive of racial differences (4,12, 14). Apical hypertrophy, which is usuably clinically benign, is frequently associated with systemic hypertension in older men (14). The pathophysiobogic findings of hypertrophic cardiomyopathy indude left ventricular hypertrophy that beads to subaortic stenosis, abnorma! diastolic function, and myocardial ischemia. Symptoms include exertional angina and dyspnea, fatigue, syncope, arrhythmia, and sudden death (13,14). Another important pathophysiologic mechanism is systolic anterior motion of the mitral valve. It is suggested that the Venturi effect of rapid flow through the narrow outflow tract causes the anterior leaflet of the mitral
valve
to displace
anteriorly
to-
ward the septum. Again, mitral regurgitation is explained by the presence of the displaced mitral leaflet (13). Cardiac MR imaging with electrocardiographic gating sharply de!ineates the myocardium between the high-signal-intensity area of epicardial fat and the signal void of the cayity. Thus, MR imaging in patients with hypertrophic cardiomyopathy provides useful information about the myocardial hypertrophic process and enables measurement of the wall thickness and of the myocardial mass (7-11).
We
cardial
mass
by Higgins
onstrated
did
not
measure
in our
series.
et a! (15),
varying
MR
the
myo-
ing
and
api-
was
gross
correlation
pressure gradient across tract of the left ventricle at catheterization and of asymmetric thickening septum demonstrated at especially in association valve displacement dur-
systobe.
Echocardiography accepted
diagnosis
as a screening
of hypertrophic
has been study
widely for the
cardiomy-
opathy and as a definitive diagnostic modality at the same time (13,16,17). However, the advantages of MR imaging over two-dimensional echocardiography include a large field of view and sharp interfaces that enable accurate myocardial evaluation for the location, severity, and extent of the abnormality. On the basis of our experience, MR imaging can provide objective information for the appropriate treatment of hypertrophic cardiomyopathy. More detailed analysis of myocardia! abnormality for the evaluation of mitrab valve abnormality can be anticipated with cine and contrast material-enhanced MR imaging.
#{149}
References 1. Goodwin 2. 3.
JF. The frontiers of cardiomyopathy. Br Heart J 1982; 48:1-18. Shah PM. IHSS-HOCM-MSS-ASH? Circulation 1975; 51:577-580. Brunwald E, Morrow AG, Cornell WP, Aygen MM. Hillbish TF. Idiopathic hypertrophic subaortic stenosis. Am J Med 1960;
29:924-925. 4.
dem-
wall thicknesses through the left ventricubar myocardium. The thickness of the septab and posterolaterab wall in
There
between the the outflow demonstrated the severity of the basal MR imaging, with mitral
In a study images
to posterolateral
cab to posterolaterab-indicate the severity of asymmetric thickening in patients with hypertrophic cardiomyopathy (16). In our series, transverse MR imaging demonstrated anterior displacement of the mitral valve during systobe. Also, narrowing of left ventricular outflow and an enlarged left atrium were revealed in patients with resting obstructive asymmetric septal hyper-
abnormal
5.
Wigle ED, Heimbecker RO, Gunton RW. Idiopathic ventricular septal hypertrophy causing muscular subaortic stenosis. Circulation 1962; 26:325-340. Sakamoto T, Tei C, Murayama M, et a!. Giant T wave inversion as a manifestation of asymmetrical apical hypertrophy (AAH) of the left ventricle: echocardiographic and
6.
7.
8.
9.
, . - Jpn HeartJ 1976; 17:611-629. Yamaguchi H, Ishimura 1, Nishiyama 5, et a!. Hypertrophic nonobstructive cardiomyopathy with giant negative T waves (apical hypertrophy): ventriculographic and echocardiographic features in 30 patients. Am J Cardiol 1979; 44:401-412. Kaufman L, Crooks LE, Sheldon PE. The potential impact of nuclear magnetic resonance imaging on cardiovascular diagnosis. Circulation 1983; 67:251-259. Lanzer P, Botvinick E, Kaufman L, David P, Lipton MJ, Higgins CB. Cardiac imaging using gated nuclear magnetic resonance. Radiology 1984; 150:121-127. Higgins CB, Stark D, McNamara M, Lanzer P, Crooks LE, Kaufman L. Multiple magnetic resonance imaging of the heart and
10.
11.
12.
13.
14.
446
Radiolov
#{149}
major vessels: studies in normal volunteers. AJR 1984; 142:661-667. Wesbey G, Lanzer P, Botvinick E, Lipton MJ, Higgins CB. Imaging and characterization of acute myocardial infarction in vivo by gated nuclear magnetic resonance. Circulation 1984; 69:125-130. Higgins CB, Lanzer P, Stark D, et a!. Imaging by nuclear magnetic resonance in patients with chronic ischemic heart disease. Circulation 1984; 69:523-531. Louie EK, Maron BJ. Apical hypertrophic cardiomyopathy: clinical and two-dimensional echocardiographic assessment. Ann Intern Med 1987; 106:663-670. Maron BJ, Bonow RO, Cannon RO III, Leon MB, Epstein SE. Hypertrophic cardiomyopathy: interrelations of clinical manifestations, pathophysiology, and therapy. N EnglJ Med 1987; 316:780-789. Park YB, Lee WS, Kim DK, Choi YS, Seo JD, Lee YW. Clinical and morphological features of hypertrophic cardiomyopathy in
15.
16.
17.
Korean patients. J Korean Med Sci 1989; 4:163-169. Higgins CB, Byrd BF, Stark D, et a!. Magnetic resonance imaging in hypertrophic cardiomyopathy. Am J Cardiol 1985; 55: 1121-1 126. Maron BJ, Epstein SE. Hypertrophic cardiomyopathy: recent observations regarding the specificity of three hallmarks of the disease: asymmetric septal hypertrophy, septal disorganization and systolic anterior motion of the anterior mitral leaflet. Am Cardiol 1980; 45:141-154. Henry WL, Clark CE, Epstein SE. Asymmetric septal hypertrophy (ASH): echocardiographic identification of the pathognomonic anatomic abnormality of IHSS. Circulation 1973; 47:225-233.
November
1992
